Archive

The incidence of all-cause mortality among residents of assisted living settings in the US between January and August 2020 was 17% higher compared to the same time period in 2019. Among the 10 states with the highest COVID-19 community spread, during that time period the incidence of all-cause mortality was 24% higher.

A modeling study found that the approach to distribution of SARS-CoV-2 vaccines between February 19 and Match 17, 2021 in the US may have created “vaccine deserts”, defined as areas with localized, geographic barriers to vaccine-associated herd immunity, which the authors suggest may affect population-wide efforts to curb SARS-CoV-2 transmission.

The incidence of multisystem inflammatory syndrome in children (MIS-C) in the US was 5.1 per 100,000 person-months and 316 per 1,000,000 (0.0003%) SARS-CoV-2 infections, based on a retrospective cohort study of young persons under 21 years of age with SARS-CoV-2 infection diagnosed April-June 2020 in 7 US states that identified 248 cases of (MIS-C). The authors conclude that these results indicate MIS-C was a rare complication associated with SARS-CoV-2 during this time period.

The SARS-CoV-2 B.1.1.7 (Alpha) variant accounted for 66% and the P.1 (Gamma) variant accounted for 5% of US infections during April 11-24, 2021, according to population-weighted CDC estimates. The estimated proportion of B.1.1.7 (Alpha) infections in the region including Washington State was 52%.

Elderly residents (n=71, median age 81 years) exhibited delayed and reduced humoral and cellular responses elicited by the Pfizer-BioNTech vaccine compared to a younger cohort of vaccinated healthcare workers (n=123, median age 34 years) in Germany. Neutralizing antibody responses did not reach ≥90% until 4 weeks after the second dose in the older cohort compared to 3 weeks after the first dose in the younger cohort.

A statewide survey of opioid treatment programs (OPTs) in Connecticut found no increases in methadone-involved fatalities relative to other opioid-involved fatalities, despite dramatic changes in practices during the COVID-19 pandemic, including increases in the proportion of patients who received take-home doses.

A study of the impact of Washington State’s exposure notification tool, WA Notify, estimated that the tool averted 6,240 COVID-19 cases and saved 30-120 lives during the first four months of implementation based on an estimated COVID-19 case fatality of 1.4%, a secondary attack rate of 12% and a quarantine effectiveness of 53%.

A study of persons who received one dose of the AstraZeneca COVID-19 vaccine found that receipt of a heterologous boost with the Pfizer-BioNTech vaccine induced significantly higher frequencies of spike-specific CD4 and CD8 T-cells and neutralizing antibodies compared to receipt of a second dose of AstraZeneca, which the authors conclude suggests a heterologous vaccination strategy may be acceptable in persons unable to receive a second dose of AstraZeneca.

Preventive treatment with the monoclonal antibody bamlanivimab reduced the risk of COVID-19 among residents and staff of skilled nursing facilities who were negative for SARS-CoV-2 infection and seronegative at baseline in a randomized trial (8.5% vs 15.2%, OR=0.43 95% CI 0.28-0.68).

A large-scale national survey in the United Kingdom conducted in April 2021 (n=17,611) found vaccine passports could increase hesitancy among those not fully vaccinated, particularly among males, those having a higher degree a vaccine implementation of vaccine, and individuals with lower baseline intent to initiate vaccination (including Black or Black British respondents, younger age groups, and non-English speakers).

Breakthrough SARS-CoV-2 infection rates were not statistically significantly different by sex or the type of mRNA vaccine administered among a cohort of US veterans (n=14,875) with a PCR test at least 7 days after receiving the second dose of an mRNA vaccine (Pfizer-BioNTech or Moderna). Risk of breakthrough infection increased with age and anemia and was lower among Black compared to white veterans.

COVID-19 mRNA vaccines were 60% effective against symptomatic SARS-CoV-2 infection 14-20 days after the first dose and 91% effective ≥7 days after the second dose in a test-negative study among symptomatic adults in Ontario, Canada between December 2020 to April 2021 (n=324,033), with even higher effectiveness against severe outcomes. Vaccine effectiveness remained high against variants of concern.

Breakthrough SARS-CoV-2 infections at least 14 days following the first dose of the Oxford-AstraZeneca or Pfizer-BioNTech vaccines were 3-fold more common among those with frailty among adults aged ≥60 years, based on findings from a study that matched infected and non-infected vaccinated individuals in the UK. Vaccinated individuals who developed infection reported fewer symptoms and had 64% lower risk of hospitalization than matched non-vaccinated individuals.

An analysis of SARS-CoV-2-positive samples from hospitalized and non-hospitalized persons in Germany found that high viral loads (> 109 copies per swab) were present in 8% of samples, 1/3 of which were from pre-symptomatic, asymptomatic, or mildly symptomatic persons. Mean number of days from viral shedding onset to peak viral load was 4.3. These results indicate that some people with mild or no symptoms may be as infectious as persons with severe infection.

Based on observational results from a large case control study, the effectiveness of the Pfizer-BioNTech vaccine against symptomatic SARS-CoV-2 infection caused by the B.1.617.2 variant of concern (first described in India) was 34% after the first dose and 88% after the second dose. By contrast, effectiveness against the B.1.1.7 variant was 51% after the first dose and 93% after the second dose. Two doses of the Oxford-AstraZeneca vaccine showed 60% effectiveness against B.1.617 compared to 66% against B.1.1.7. Findings are based upon an analysis of 12,675 sequenced cases in England (92% of which are B.1.1.7).

A population-based cohort study among pregnant people in England (n = 342,080) screened for SARS-CoV-2 at the time of delivery hospitalization found risk of fetal death (aOR = 2.2), preterm birth (aOR = 2.2), preeclampsia/eclampsia (aOR = 1.6), and emergency Cesarean delivery (aOR = 1.6) were all significantly higher among SARS-CoV-2 positive individuals.

A large retrospective cohort study of US adults aged 18-65 enrolled in commercial insurance found that 14% of individuals with SARS-CoV-2 infection, 9% of persons without SARS-CoV-2 infection and 13% of persons with a non-COVID viral lower respiratory tract illness developed ≥1 new clinical sequela after the acute phase of disease.

SARS-CoV-2 infections among residents of nursing homes in the US decreased among both vaccinated and unvaccinated residents over time following vaccination clinics that administered mRNA COVID-19 vaccines. Cases occurred in 4.5% of vaccinated residents within 0-14 days after the first dose and declined to 0.3% of vaccinated residents 14 days after the second dose. A similar pattern was observed among unvaccinated residents, which the authors suggest indicates that high vaccination coverage, along with existing mitigation measures, conferred a degree of herd immunity among unvaccinated nursing home residents.

COVID-19 vaccination coverage among US adults aged 18-64 years was lower in rural (39%) than urban (46%) counties as of April 10, 2021 according to CDC data. Among 46 health jurisdictions where urban-rural comparisons could be assessed, only 5 had higher coverage in rural counties and another 5 had similar coverage (within 1%). Disparities persisted across age and sex.

The Pfizer-BioNTech vaccine was 90% effective in preventing any SARS-CoV-2 infection during 7-27 days after the second dose (protection period) compared to 1-7 days after the first dose (reference period) based on a cohort study in Israel (n=1.2 million). Vaccine effectiveness was 71% among immunosuppressed participants, 82% among those aged ≥65 years, and 52% among those in both groups.

Interim results from a large study of US healthcare personnel indicated that one dose of either the Pfizer-BioNTech or Moderna vaccines was 82% effective against symptomatic COVID-19 and 2 doses were 94% effective.

An in vitro study of serum neutralization after two doses of the Pfizer-BioNTech vaccine found that variants B.1.526, B.1.429, and B.1.1.7+E484K remained susceptible to vaccine-elicited neutralizing antibodies, indicating that the E484K mutation, also found in the B.1.351 and B.1.526 lineages, may not compromise the neutralization of vaccine-induced antibodies.

The CDC released updated guidance on May 13, 2021 that fully vaccinated individuals no longer need to wear face coverings or physically distance in most indoor and outdoor settings regardless of crowd size. Mask wearing is still recommended in certain indoor settings, such as healthcare facilities, transportation hubs, and correctional facilities. Fully vaccinated people should continue to follow any applicable federal, state, local, tribal, or territorial laws, rules, and regulations.

Among nearly 2.5 million contacts of over 1 million SARS-CoV-2 index cases in England, index cases with lower cycle threshold values (suggesting higher viral loads) tended to have higher attack rates. Attack rates were 55% higher among index cases with S gene target failure (proxy for the B.1.1.7 variant), and highest among household contacts (9%). Contacts of children were the least likely to test positive.

COVID-19 patients with type 2 diabetes were at a greater than 2-fold elevated risk of COVID-19-related hospitalization, admission to ICU, and death compared to age- and sex- matched controls in a nationwide study in Sweden. COVID-19 patients with type 1 diabetes were at similarly increased risk when compared to matched controls, but unlike type 2 diabetes, there was no independent risk after adjustment for sociodemographic factors, pharmacological treatment, and comorbidities.

Among Italian patients (n=286) who recovered from mild-to-moderate symptomatic COVID-19, the prevalence of altered sense of smell or taste one year after initial symptom onset was more than 20%.

A prospective cohort study of SpaceX employees (N=4,111) found a 91% lower odds of SARS-CoV-2 reinfection over 6 months of follow-up among participants with detectable SARS-CoV-2 antibodies at baseline, potentially indicating that previous infection provides at least 6 months of protection from SARS-CoV-2 reinfection for most individuals.

The Pfizer-BioNTech vaccine was estimated to be 90% effective against the B.1.1.7 SARS-CoV-2 variant and 75% effective against the B.1.351 variant 14 days or more after the second dose in Qatar. Estimated vaccine effectiveness against severe, critical, or fatal SARS-CoV-2 infection caused by any variant was 97%.

The proportions of persons infected with the SARS-CoV-2 B.1.526 variant (first identified in New York) who have poor clinical outcomes does not appear different from other circulating strains. Both breakthrough infections in fully vaccinated persons and possible reinfections were rare, but did not appear more common with the variant.

A transmission model based on CDC modeling tools found that in a pre-K-12 school setting in the US, layering mitigation strategies with contact tracing to produce a net effectiveness of 69% could result in a cumulative incidence of SARS-CoV-2 infection of less 0.9% over 6 months when community incidence is low. Across all scenarios of mitigation strategies and community incidence, hospitalizations did not exceed 0.5% of the school population.

The Johnson & Johnson/Janssen vaccine showed a real-world effectiveness of 76.7% in preventing SARS-CoV-2 infection at least two weeks after vaccination among patients in the Mayo Clinic Health system, according to an analysis of data between February 27th and April 14th, 2021.

Patients with severe COVID-19 who received the anti-inflammatory medication tocilizumab were more likely to be discharged from the hospital (57% vs. 50%) and less likely to die (31% vs. 35%) in a randomized trial.

SARS-CoV-2 secondary attack rates were 6% in households were the index case received either the Oxford-AstraZeneca or Pfizer-BioNTech vaccines prior to infection compared to 10% in households with unvaccinated index cases. Contacts of vaccinated index cases had 38-49% lower odds of infection compared to matched contacts of unvaccinated index cases. Only 7% of the index cases had received two vaccine doses by the time of their infection.

Among adults age 65 and older, the Pfizer-BioNTech and Moderna vaccines were 94% effective against hospitalization for COVID-19 among fully vaccinated individuals, and 64% effective among partially-vaccinated individuals, according to data from US hospitals during January-March 2021.

The Advisory Committee on Immunization Practices (ACIP) reaffirmed its interim recommendation for use of the Johnson & Johnson COVID-19 vaccine in all persons aged ≥18 years on April 23, 2021, with the addition of a warning that rare clotting events may occur in female vaccine recipients aged 18-49 years. A risk-benefit analysis that guided ACIP recommendations suggested that for every 1 million doses administered to women aged 18-49 years, 297 COVID-19-related hospitalizations, 56 ICU admissions, and 6 deaths could be prevented, compared with 7 expected cases of thrombosis with thrombocytopenia.

The Pfizer-BioNTech vaccine showed 70% effectiveness against SARS-CoV-2 infection 21 days after the first dose and 85% seven days after the second dose among hospital staff in the UK.

A large, retrospective cohort analysis of patients enrolled in a Houston healthcare network (N=91,134) found that vaccination with 2 doses of either the Pfizer-BioNTech or Moderna vaccine reduced the risk of COVID-19 hospitalization by 96% and COVID-19 associated deaths by 99%. Additionally, the study found that persons with partial immunization, defined as 2-weeks following the 1st dose through 7 days following the 2nd dose, had a 77% lower risk of hospitalization and a 64% lower risk of death.

2 SARS-CoV-2 breakthrough infections (infection ≥14 days after the second vaccine dose) were detected in a cohort of 417 university employees in New York City. Both were previously healthy without known risk factors. Viral genome sequencing revealed variants of likely clinical importance.

Twenty-two possible breakthrough SARS-CoV-2 infections (infection ≥14 days after the second vaccine dose) were identified among skilled nursing facility staff and residents in the Chicago area. Most infections were asymptomatic. Two vaccinated residents were hospitalized, one resident died due to multiple concurrent infections, and no facility-associated secondary transmission occurred.

In Brazil, younger patients without pre-existing conditions accounted for a larger proportion of severe COVID-19 cases leading to death in the second wave of cases (February 2021) compared to the first wave (November-December 2020). The second wave was predominated by the P.1 variant.

Few kidney transplant recipients (n = 51/136) who had been fully vaccinated with the Pfizer-BioNTech vaccine developed an antibody response to the SARS-CoV-2 spike protein, suggesting that this population may remain at risk of infection despite vaccination.

An estimated 545,600 to 660,200 excess deaths occurred in the US between January 2020 and February 2021, of which 75% to 88% were directly associated with COVID-19.

Text messages sent to COVID-19 vaccine-eligible patients increased appointment and vaccination rates by 86% and 26%, respectively, in a large, randomized trial (n > 110,000). A follow-up trial among patients who had not made first-dose appointments 8 days after the first trial (n > 90,000) repeating the intervention increased appointment and vaccination rates by 52% and 16%, respectively.

Adults with COVID-19 who were not hospitalized and who received the monoclonal antibody bamlanivimab had a significantly lower 30-day hospitalization rate than those who did not receive the treatment.

Prior SARS-CoV-2 infection was associated with an 84% lower risk of infection according to the SIREN Study, a large cohort study of over 25,000 individuals. From June to December 2020, reinfections/infections were detected in 0.02% (155 of 8,278) of participants positive at baseline compared to 0.1% (1,704 of 17,383) of participants negative at baseline. The authors found no evidence that the emergence of the B.1.1.7 variant was linked to increased reinfection rates.

Emergency department visits for COVID-19 were 1.7 times higher among Hispanic and American Indian or Alaska Native persons and 1.4 times higher among Black persons, than white persons between October-December 2020, based on data from 13 US states.

Among healthcare workers in Great Britain, one dose of the Pfizer-BioNTech COVID-19 vaccine resulted in a 4-fold reduction in asymptomatic SARS-CoV-2 infection ≥12 days post-vaccination (from 0.8% to 0.2%).

A single dose of the Pfizer-BioNTech vaccine substantially increased neutralizing activity against SARS-CoV-2 variants B.1.1.7, B.1.351, and P.1 among 6 previously infected healthcare workers. Geometric mean titers against B.1.351 increased by 228-fold.

Antibody activity elicited by the Moderna vaccine remained high 6 months after the second dose in all participants in the initial phase 1 trial.

An estimated 37,300 children aged 0-17 years in the US had lost at least 1 parent due to COVID-19 by February 2021, according to demographic simulations using kinship networks. Roughly 3 in 4 children who are estimated to have lost a parent are adolescents aged 10-17 years, and Black children were disproportionately affected.

Spike-specific IgG antibody levels and ACE2 antibody binding inhibition responses were similar between healthcare workers in California who had been previously infected with SARS-CoV-2 and received a single dose of the Pfizer-BioNTech vaccine and those who had no prior infection and had received both vaccine doses.

In a Wisconsin state prison, 79% of the incarcerated population and 3% of staff members contracted SARS-CoV-2 within 8 weeks after the prison received six newly transferred persons who were not initially identified to be SARS-CoV-2 positive at time of intake. Genome sequencing of 172 cases showed that all specimens belonged to the same lineage.

45% of 5,110 residents from three prisons and 13 jails across four states (all three prisons and 10 jails in Washington State) said they would refuse to receive a COVID-19 vaccine. The most common reason for vaccination refusal was distrust of health care, correctional, or government personnel or institutions. Willingness to be vaccinated was lowest among Black participants, participants aged 18–29 years, and those who lived in jails vs prisons.

In a press release, Pfizer reported that the Pfizer-BioNTech vaccine conferred 100% efficacy against COVID-19 in adolescents age 12-15 with no previous history of SARS-CoV-2 infection. The vaccine also elicited a strong neutralizing antibody response one month after the second dose, and side effects were similar to those observed among participants aged 16-25 in previous trials.

93% of the largest 50 private and 50 public US institutions of higher education offered some in-person teaching for the Fall 2020 semester, 71% of which offered a hybrid reopening structure (≥25% students on campus). Nearly all institutions employing mitigation strategies adopted masking and physical distancing mandates, and over half reduced the density of on-campus housing and classroom density. Over half required entry testing for SARS-CoV-2, and 32% required testing at regular intervals.

The Pfizer/BioNTech and Moderna vaccines were 90% effective at preventing SARS-CoV-2 infection after full immunization and 80% after partial immunization, according to interim estimates among healthcare personnel and essential workers in the US.

Only 1% of over 14,000 nursing home residents in the UK who have received the first dose of either the Pfizer-BioNTech or Oxford-AstraZeneca vaccines reported a positive SARS-CoV-2 PCR test in an observational study from December 2020 to March 2021. 90% of infections occurred within 28 days of the first dose.

Despite low adherence to mitigation measures and low rates of improvements to ventilation systems, minimal in-school transmission of COVID-19 was documented during in-person learning in a school system in Wood County, Wisconsin. Between August and November 2020, only 7 cases among children were attributed to school-based transmission despite high levels of community transmission (none among staff).

School-related COVID-19 incidence was <1% among Florida K-12 students (August-December 2020), were most schools resumed in-person instruction sometime during August 2020. The incidence among students was correlated with community incidence and was highest in smaller counties, districts without mask requirements, and those that reopened earliest after closure in March 2020. Approximately 11% of K-12 schools experienced outbreaks with a median of 6 cases per outbreak. 20% of school outbreaks were associated with activities outside of the classroom.

US parents of children aged 5-12 years who received virtual or combined virtual/in-person instruction were more likely to report both poor parent and child well-being compared to parents of children who received in-person instruction only. Findings are based on a nationwide survey of 1,290 parents, of whom 46% reported their child was receiving virtual instruction only.

Two doses of the Oxford-AstraZeneca (ChAdOx1 nCoV-19) vaccine did not show protection against mild-to-moderate COVID-19 due to infection with the B.1.351 variant in a randomized trial in South Africa. The trial population did not experience enough severe disease for an analysis of vaccine efficacy against severe disease.

Only 17% (76 of 436) of solid organ transplant recipients developed detectable antibody responses at a median of 20 days after the first dose of either the Moderna or Pfizer-BioNTech vaccines, according to a convenience sample of US patients. Transplant recipients who were receiving immunosuppression therapy, older transplant recipients, and those vaccinated with the Pfizer-BioNTech vaccine (as compared to the Moderna vaccine) were less likely to develop detectable antibody responses.

A longitudinal cohort study of healthcare workers in England showed that both natural infection and vaccination with either the Pfizer/BioNTech or Oxford/AstraZeneca vaccine provided more than 85% protection against symptomatic and asymptomatic SARS-CoV-2 infection, including with the B.1.1.7 variant.

Based on a press release from the manufacturer, the Novavax vaccine had an efficacy of 96.4% against mild, moderate and severe disease caused by the original COVID-19 strain in a Phase 3 trial in UK, and was 100% protective against hospitalization and death.

The SARS-CoV-2 B.1.1.7 variant was associated with an overall 1.6-fold increase in risk of death compared with infection with previous strains. These findings are based on almost 55,000 UK patients considered to be relatively low-risk who were diagnosed with SARS-CoV-2 in the UK between October 2020 to January 2021.

Among children with multisystem inflammatory syndrome associated with SARS-CoV-2 infection, ICU admission was more likely among older children (6–12 years, aOR = 1.9; 13–20 years, aOR = 2.6) compared with those aged 0–5, non-Hispanic Black than non-Hispanic white patients (aOR = 1.6), and among patients experiencing shortness of breath (aOR = 1.9) and abdominal pain (aOR = 1.7).

New recommendations from the CDC indicate that fully vaccinated individuals can gather with other vaccinated individuals indoors safely without wearing masks. This guidance comes in light of increasing evidence that vaccines can reduce likelihood of asymptomatic infection and transmission of SARS-CoV-2. The CDC recommends that everyone continue to practice COVID-19 precautions such as wearing masks in public and avoiding medium to large-sized gatherings.

Two SARS-CoV-2 outbreaks occurred among US university athletic programs during the fall 2020 despite mandatory directly observed daily antigen testing, suggesting that antigen testing along may not be sufficient to prevent outbreaks in congregate settings.

Mask mandates in the US were associated with decreases in the growth rate of daily COVID-19 cases and deaths after implementation during March-December 2020. During the same period, reopening of any on-premises dining was associated with increases in the growth rates of daily COVID-19 cases and deaths.

The SARS-CoV-2 B.1.1.7 variant may be 65-82% more transmissible than earlier strains, according to a model fitted to COVID-19 data from the UK around the time of the variant’s emergence. The authors estimate that COVID-19 related deaths and hospitalizations in England in 2021 could exceed those in 2020 in the absence of a substantial vaccine-rollout (2 million people fully vaccinated per week), even with stringent non-pharmaceutical interventions.

A study of the real-world effectiveness of the Pfizer-BioNTech and Oxford-AstraZeneca vaccines indicated that vaccination with a single dose of either vaccine was associated with a significant reduction in symptomatic COVID-19 cases in older adults, with strong protection against severe disease.

While the risk of reporting COVID-19-related outcomes was approximately 2-fold higher for US household members living with a child attending in-person learning, risks largely disappeared among household members of children attending schools with 7 or more mitigation measures and were completely absent among those reporting 10 or measures.

A meta-analysis of randomized clinical trials comparing patients with COVID-19 treated with convalescent plasma versus controls found no significant differences in all-cause mortality, length of hospital stay, mechanical ventilation use, clinical improvement, or clinical deterioration.

An analysis of publicly available data on COVID-19 mortality in England and Wales suggests that absolute mortality rates (all cause) for teachers were low, and that primary school teachers were not at elevated risk of death compared to the general population. Secondary school teachers had a slightly higher risk of dying of COVID-19 relative to all professionals and working-aged people.

Real world effectiveness of the Pfizer vaccine 7 or more days after the second dose was 92% against documented SARS-CoV-2 infection, 87% against hospitalization, and 92% in preventing severe disease in an observational study.

The Johnson and Johnson one-dose SARS-CoV-2 vaccine candidate Ad26.COV2.S was determined by the FDA to have met requirements for emergency use authorization. The vaccine efficacy against moderate to severe COVID- was 66.9% when considering cases occurring at least 14 days after vaccination, and 66.1% considering cases occurring at least 28 days after vaccination. Efficacy against severe/critical COVID-19 occurring at least 14 days and at least 28 days after vaccination was 76.7% and 85.4%, respectively.

Mask adherence among children in US summer camps was approximately 34% among surveyed summer camps (n=486) that operated in 2020 and 15% of camps reported one or more confirmed COVID-19 cases in either campers or staff. Facial coverings among staff and targeted physical distancing measures were associated with lower COVID-19 risks, but not to the same degree as campers wearing masks.

In US-based clinical COVID-19 vaccine trials (n = 219,555 participants), participants who were Black or African American (10.6%), American Indian or Alaska Native (0.4%), Hispanic or Latino (11.6%), or older than 65 (12.1%) were underrepresented, while women (56.0%) were overrepresented, compared to the distribution of the US population.

Monitoring of the U.S. vaccination effort using the Vaccine Adverse Events Reporting System indicates reassuring safety profiles for both the Pfizer and Moderna COVID-19 vaccines.

Real-world vaccine efficacy of the Moderna and Pfizer vaccines against SARS-CoV-2 infection at 36 days or longer after the first dose was 89% in a 1:1 propensity score matched analysis of over 60,000 individuals between December 2020 to February 2021. 14-day hospital admission rates were lower among vaccinated individuals who were subsequently diagnosed with COVID-19 compared to matched unvaccinated counterparts (3.7% vs 9.2%).

The Minnesota Department of Health identified eight people who had been infected with the B.1.1.7 SARS-CoV-2 variant (first detected in the UK) from December 18, 2020–January 11, 2021. Three people had a history of international travel during the 14 days before illness onset, and three additional people had traveled domestically.

The SARS-CoV-2 B.1.1.7 variant (first described in the UK) showed similar sensitivity to neutralizing activity of convalescent sera and sera from vaccinated individuals compared to the wild-type virus. In contrast, neutralization was lower against the B.1.351 variant (first described in South Africa).

The CDC released new guidelines for reopening K-12 schools for in-person learning, noting that evidence suggests that many K-12 schools that have strictly implemented mitigation strategies have been able to open safely for in-person instruction and remain open.

Approximately 65% of nearly 4,000 students participating in a web survey in October 2020 reported wearing masks all the time when in classrooms, hallways, or stairwells. Mask use was lower in other indoor spaces, such as restrooms and cafeterias (when not eating), and lowest in outdoor spaces such as outside school property.

Sera from individuals who had received the Pfizer/BioNTech vaccine showed equivalent neutralization against SARS-CoV-2 viruses engineered to include key mutations from variant strains emerging from the UK (69/70-deletion + N501Y + D614G) and South Africa (E484K + N501Y + D614G). The authors suggest this indicates a minimal impact of these mutations on neutralization by sera from vaccinated individuals, but the impact on vaccine efficacy is unknown.

Whole-genome sequencing identified a cluster of SARS-CoV-2 infections that involved 14 patients and 38 staff members at Brigham and Women’s Hospital in Boston. The cluster occurred despite infection prevention measures that included universal testing, mandatory surgical masks and eye protection, patient cohorting into negative pressure wards, free PCR testing for employees, and mandatory sick leave.

Sequencing of SARS-CoV-2 genomes collected from testing facilities in the U.S. between December 2020 to January 2021 found multiple independent introductions of the B.1.1.7 variant into the U.S. by late November 2020, with community transmission leadings to its spread to 30 or more states as of January 2021.

The ChAdOx1 (Oxford-AstraZeneca) vaccine against symptomatic COVID-19 disease had similar efficacy against B.1.1.7 and non-B.1.1.7 viral lineages. Among those who were vaccinated and subsequently became infected with SARS-CoV-2, both the duration of shedding and viral load were lower than among control participants.

The B.1.1.7 (UK) SARS-CoV-2 variant may increase the risk of death by 30%, based on an analysis of SARS-CoV-2 community test results in the UK that identified B.1.1.7-associated infections using S gene target PCR failure.

A randomized trial (RECOVERY) of azithromycin to treat COVID-19 found no differences between treatment and placebo groups in terms of survival, duration of hospitalization, proportion of patients discharged alive within 28 days, or proportion of patients meeting composite endpoints of mechanical ventilation or death.

Interim analysis of the phase 3 trial of the recombinant adenovirus (rAd)-based vaccine Gam-COVID-Vac (Sputnik V) (n=19,866) showed an efficacy of 91.6% (CI: 85.6%-95.2%) in preventing COVID-19 by 21 days after the first dose (the day of dose 2). The observed vaccine efficacy was >87% in all age and sex subgroups.

The American Academy of Pediatrics guidelines for children returning to athletic activities recommend wearing cloth face masks during indoor sports and consulting a physician regarding potential cardiovascular symptoms in children with COVID-19 prior to their return to activity

Health care workers hospitalized for COVID-19 were less likely to require admission to an intensive care unit and less likely to be admitted for 7 days or longer when compared to matched non-healthcare workers. There were no differences between HCWs and non-HCWs in terms of need for mechanical ventilation.

Recipients of the 2-dose regimen of the Pfizer vaccine (n=20) had similar neutralizing titers against SARS-CoV-2 viruses engineered to contain key spike protein mutations from B.1.1.7 variant (1.4-fold) and B.1.351 variant (0.8-fold) compared to neutralizing geometric mean titers (GMTs) against wild-type SARS-CoV-2.

This document is intended to serve an updated resource compiling information about what is known about COVID-19 and SARS-CoV-2 in the context of schools, with a primary focus on K-12 grades.

The SARS-CoV-2 variant B.1.351 (South Africa) showed some resistance to neutralization by certain monoclonal antibodies, convalescent plasma, and sera from people who had received the Pfizer or Moderna vaccines. The B.1.1.7 (UK) variant also showed some resistance to neutralization, but to a lesser extent.

An outbreak of SARS-CoV-2 associated with a Florida high school wrestling tournament in December 2020 had an attack rate of at least 30% and a secondary attack rate of at least 9%. Among contacts, household members had the highest attack rate (at least 30%) and test positivity rate (60%).

Sera from human subjects or non-human primates that received the mRNA-1273 (Moderna) vaccine showed no significant reduction in neutralization activity against the SARS-CoV-2 B.1.1.7 variant emerging from the UK, but reduced activity against the B.1.351 variant emerging from South Africa.

Compared to a 59% reduction in transmission with a 14-day quarantine period, a 7-day quarantine with a negative RT-PCR test or a negative antigen test on day 7 could reduce transmission by 54% and 50%, respectively.

The SARS-CoV-2 501Y.V2 lineage, first identified in South Africa, was found to largely escape neutralization from both monoclonal antibodies and convalescent polyclonal sera capable of neutralizing existing parent lineages.

The sensitivity of the BinaxNOW antigen test to detect people infected with SARS-CoV-2, compared with RT-PCR, was 35.8% among asymptomatic persons and 64.2% among and symptomatic persons. Specificity was near 100% in both groups. Sensitivity was higher among specimens positive for viral culture.

A more highly transmissible variant of SARS-CoV-2, lineage B.1.1.7, has been confirmed in 76 cases in the United States as of January 13, 2021. Models suggest that this variant has potential to drive a new phase of exponential growth in cases in the US, and that even if vaccination protects against infection, substantial transmission of the variant will continue until it becomes the dominant strain.

Interim results of the phase 1-2a trial of the Johnson & Johnson adenovirus vector vaccine (Ad26.COV2.S) showed SARS-CoV-2 neutralizing-antibody titers were detected in 90% or more of all participants on day 29 after the first dose and reached 100% by day 57 regardless of age or dose group. The most frequent adverse events included fatigue, headache, and fever.

During March 1–December 12, 2020, a total of 2,871,828 laboratory-confirmed cases of COVID-19 in young people aged 0–24 years were reported in the United States, with the majority (57%) occurring among those aged 18–24 years. Temporal incidence patterns suggest that young adults might contribute more to community transmission than do younger children.

Rates of pediatric hospitalization for COVID-19 varied considerably across states from May to November 2020. In May, rates ranged from 0 per 100,000 (HI and RI) to 5.4 per 100,000 (NJ) and in November ranged from 3.4 per 100,000 (NH) to 32.8 per 100,000 (AZ). Some states experienced a rapid increase in rates, with Utah experiencing a 5,067% increase (from 0.3 to 15.5 per 100,000) within 3 months.

Among collegiate athletes exposed to COVID-19 (n=1,830), one quarter had positive test results during quarantine with a mean of 3.8 days from quarantine start until the positive test result.

Transmission of SARS-CoV-2 increased rapidly at an Arkansas university within two weeks of the start of the 2020-2021 academic year, likely facilitated by congregate living settings and gatherings, particularly fraternity and sorority recruitment activities.

Anti-spike and anti-RBD IgG antibodies persisted up to 6-8 months post-symptom onset in 90% and 88% of individuals, respectively. Paired timepoint analysis showed that anti-spike and anti-RBD IgG declined with a half-life of 68 and 69 days, respectively.

An analysis combing seroprevalence data with reported cases estimated 46,910,006 SARS-CoV-2 total infections, 28,122,752 symptomatic infections, 956,174 hospitalizations, and 304,915 deaths occurred in the US through November 15, 2020. The authors estimate that 14% of Americans were infected with COVID-19 by mid-November.

Mutations in three main epitopes of the SARS-CoV-2 spike receptor-binding domain (RBD) affect neutralizing activity of convalescent serum. Mutations occurring at the E484 site had the biggest average effect with a >10-fold reduction in serum neutralization in some donors. The impact of specific viral mutations on neutralization varied substantially across individuals and within the same individual over time, with no mutation completely eliminating neutralizing activity.

The Moderna vaccine mRNA-1273 showed 94.1% efficacy at preventing COVID-19, including severe disease, in a peer-review publication from the phase 3 trial. Efficacy was similar across key secondary analyses, and all severe cases of COVID-19 occurred in the placebo group.

A nationally representative longitudinal survey (n=8,167) found that self-reported likelihood of getting a COVID-19 vaccine declined from 74% in early April to 56% in early December. Significant declines in the likelihood of vaccine uptake were observed in all gender, age, racial/ethnic, and education subgroups.

Presence of anti-spike or anti-nucleocapsid IgG antibodies was associated with a reduced risk of SARS-CoV-2 reinfection among health care workers in the UK over 6 months of follow-up.

An investigation of the transmission of the mutated 501Y strain of SARS-CoV-2 circulating in the United Kingdom (UK) suggests that it may be 75% more transmissible than the previous lineage, but there does not appear to be significant spread outside of the UK despite sporadic cases in Wales, Australia, Spain, and the US.

The Advisory Committee on Immunization Practices issued an interim recommendation for use of the Moderna COVID-19 vaccine in persons aged ≥18 years for prevention of COVID-19 on December 19, 2020.

A randomized trial found that tocilizumab reduced the risk of mechanical ventilation but did not prevent deaths among patients with COVID-19 pneumonia

An interim analysis of the ongoing trial for the antibody cocktail REGN-COV2 among non-hospitalized COVID-19 patients (n=228) found a larger difference in viral loads (mean difference of -0.41 log10 copies per milliliter) among patients in treatment group compared to placebo group

The COVID-19 pandemic was associated with substantial increases in all-cause mortality among US adults aged 25-44 years from March to July of 2020. In multiple regions, deaths due to COVID-19 in this age range were similar to or exceeded unintentional opioid deaths that occurred during corresponding months in 2018.

Attending school or child care was not associated with receiving a positive SARS-CoV-2 test result among children and adolescents aged <18 years in Mississippi. By contrast, infection was more likely among children who had close contact with a person with COVID-19 and among those who attended gatherings with persons outside their household.

The US Advisory Committee on Immunization Practices issued an interim recommendation for use of the Pfizer-BioNTech COVID-19 vaccine in persons aged ≥16 years for the prevention of COVID-19.

School-based mitigation strategies recommended by CDC would cost an estimated 0.3% to 7.1% more than school expenditures reported by states in fiscal year 2018

Results of the phase 3 trial for the BioNTech and Pfizer vaccine BNT162b2 (n=21,720 in vaccine group, 21,728 in placebo group) showed a vaccine efficacy of 95%, with 8 cases of COVID-19 in the vaccine group and 162 cases in the placebo group after 2 doses.

Following school reopening in England between June 1 and July 17, 2020, only 177 COVID-19 events were identified among 57,600 educational settings. Of these, 113 consisted of a single case, nine involved two or more cases that occurred close enough in time such that secondary infection was unlikely, and 55 involved outbreaks of at least two epidemiologically linked cases. There was a median of 1 secondary case in the outbreaks. The risk of an outbreak was positively associated with the level of community COVID-19 incidence.

An interim analysis of ongoing phase 2/3 trials for the Oxford–AstraZeneca vaccine ChAdOx1 nCoV-19 showed overall vaccine efficacy was 70.4%, with no COVID-19-related hospital admissions occurring in vaccine recipients and 10 occurring in the control group.

A meta-analysis found that of 213 SARS-CoV-2 transmission clusters from 12 countries, 3.8% had a pediatric index case. The secondary attack rate was lower among pediatric than adult household contacts (RR=0.62).

From March-August 2020, data from the COVID-NET indicated that more than 1 in 5 younger adults (ages 18-49) without underlying conditions who were hospitalized with COVID-19 in the US experienced severe illness requiring ICU-level care.

The Advisory Committee on Immunization Practices recommends that health care personnel and residents of long-term care facilities be offered COVID-19 vaccination in the initial phase of the US vaccination program

In Korea, reopening schools with good adherence to mitigation measures among students did not lead to significant increases in the proportion of pediatric cases with COVID-19 in the nation (7% by May 20 and 7.2% by July 31).

SARS-CoV-2 may have been introduced in the US earlier than previously recognized based on the detection of antibodies reactive to SARS-CoV-2 found in archived samples from routine blood donations in 9 states from December 2019 and January 2020.

A model estimating the societal and healthcare burdens of SARS-CoV-2 infections indicated that there were 2.4 million hospitalizations and 44.8 million symptomatic illnesses in the U.S. from February 27–September 30, 2020, yet only 1 of every 2.5 hospitalized infections and 1 of every 7.1 non-hospitalized illnesses may have been reported.

• A model assessing the relative impact of symptom monitoring, testing, and quarantine practices on transmission of SARS-CoV-2 by infected travelers suggests that quarantining for 14 days could almost completely eliminates risk of transmission. When combined with symptom monitoring and testing, a 7-day quarantine after arrival had similar modeled effectiveness

Convalescent plasma infusion did not lead to a significant difference in 30-day clinical outcomes or death in a randomized, placebo-controlled trial among patients with severe COVID-19.

The Advisory Committee on Immunization Practices announced 4 ethical principles in developing strategies for the initial allocation of a SARS-CoV-2 vaccine: 1) maximizing benefits and minimizing harms; 2) promoting justice; 3) mitigating health inequities; and 4) promoting transparency.

Mask mandates at the county-level were associated with a decrease in the rate of COVID-19 infections in Kansas

A randomized controlled trial in Denmark did not demonstrate effectiveness of adding a mask recommendation to other public health measures in reducing SARS-CoV-2 infection among participants instructed to wear masks (OR = 0.82, 95% CI 0.54-1.23), and did not investigate the broader community benefits from mask wearing.

Final results of the candidate SARS-COV-2 vaccine produced by Pfizer, reported in a press release and not yet peer reviewed, indicate an efficacy of 95% to prevent COVID-19 disease, with evidence that it prevents severe disease.

Large-scale pooled testing combined with contact tracing and other prevention strategies at Duke University contributed to limited SARS-CoV-2 transmission and efficiently identified asymptomatic cases, which comprised over half of the 84 cases detected during fall 2020.

The incidence of out-of-hospital cardiac arrest was higher, while survival was lower, during the first weeks of the COVID-19 pandemic in the US, compared to one year prior.

Symptom-based screening of travelers at airports to prevent the spread of SARS-CoV-2 was found to be resource-intensive and overall ineffective, identifying about one case for every 85,000 travelers screened

A wedding reception in rural Maine was the likely source of subsequent outbreaks in the local community, a long-term care facility 100 miles away, and a correctional facility 200 miles away, with a total of 177 cases and 7 deaths.

Public health measures to reduce SARS-CoV-2 transmission may have had unintended benefits on other respiratory viruses, shown by  a faster decline in the reproductive number (Rt) in  the 2019-2020 seasons of influenza A&B and respiratory syncytial virus, compared to the 5 past seasons.

Intergenerational co-residence (age 18−34 years living with their parents) was associated with more deaths from COVID-19, with each additional point increase in the percent of co-residence associated with a 12% increase in cumulative deaths 100 days after onset of the pandemic in the US.

Intermittent excretion of low levels of SARS-CoV-2 RNA after hospital discharge was not associated with either secondary transmission or worsening clinical disease.

Modeling of K-12 school reopening in King County, Washington suggests that SARS-CoV-2 screening with PCR or antigen tests would provide little additional benefit if in-school countermeasures, which can be highly effective in reducing in-school transmission, are observed.

Cognitive impairments were found in 81% of inpatient rehabilitation patients (mean age 65 years) who were recovering from severe COVID-19

A study from England found that living with children was not associated with the risk of SARS-CoV-2 infection or with adverse COVID-19 outcomes. There were also no changes in risk following the closure of schools.

A qualitative study of COVID-19 vaccine trial perceptions among people from ethnic minority groups and vulnerable communities in the UK found that while many people believed that clinical research was necessary, most interviewees expressed extreme discomfort with the idea of attending a hospital for a vaccine trial.

Oxygen saturation did not decline among adults over age 65 years while they wore non-medical face masks

The scientific literature on COVID-19 is rapidly evolving and these articles were selected for review based on their relevance to Washington State decision making around COVID-19 response efforts. Included in these Lit Reps are some manuscripts that have been made available online as pre-prints but have not yet undergone peer review. Please be aware of…

Twenty counties in the US in which mass-gathering rallies associated with the US Presidential campaign were held during August-September 2020 had an average 50% increase in the COVID-19 incidence 15 days after the gathering date. In comparison, the incidence among counties without such gatherings had a 2% increase.

An outbreak investigation of SARS-CoV-2 infections among members of a university’s men’s and women’s soccer team had an attack proportion of 38% (17 out of 45 exposed to index case), with all infected cases attending at least 1 of 18 social gatherings included in the investigation.

In some areas of the US, COVID-19 has likely become the leading cause of death among young adults aged 25-44 during substantial outbreaks, surpassing unintentional overdoses.

Universal mask wearing in the United States could save an additional 129,574 lives from September 22 through the end of February 2021, or 85% mask use could save an additional 95,814 lives when compared to a reference scenario in a model from IHME.

Only 1 to 6 cases of hospital-acquired SARS-CoV-2 infection at UW Medicine were reported from April 2 to May 14, corresponding to a relatively low incidence of 0.8 to 5 cases per 10,000 patient days. More

The scientific literature on COVID-19 is rapidly evolving and these articles were selected for review based on their relevance to Washington State decision making around COVID-19 response efforts. Included in these Lit Reps are some manuscripts that have been made available online as pre-prints but have not yet undergone peer review. Please be aware of…

Despite early enthusiasm for monoclonal antibodies directed against IL-6 (tocilizumab), two randomized, open-label trials did not demonstrate substantial clinical benefit, both reporting no effect on 28-day mortality. These findings, combined with two previously reported industry sponsored trials by the manufacturer of tocilizumab, indicate that tocilizumab may not be as efficacious as suggested by early observational data.

During the first wave of the COVID-19 pandemic in Hong Kong, there was a longer time to diagnosis among people living in public rental houses and in areas with lower educational attainment. In contrast, no such association was observed during the second wave when surveillance measures were enhanced.

Children who were infected with SARS-CoV-2 at an overnight camp in Georgia in June transmitted the virus to 9% of their household contacts, with 10% of the adult secondary cases requiring hospitalization.

In an ongoing randomized controlled phase 1 trial of RNA-vaccine candidates BNT162b1 and BNT162b2, both vaccine candidates elicited similar SARS-CoV-2 neutralizing titers. BNT162b2 was associated with a lower incidence and severity of systemic reactions than BNT162b1, particularly among older adults.

Transmission events from college-aged individuals to older individuals at nursing facilities resulted in two deaths, according to genomic sequence analysis of a COVID-19 outbreak following the reopening of colleges in La Crosse County, Wisconsin.

A man from Nevada was reported as the first case of SARS-CoV-2 reinfection in North America, with genomic evidence supporting that the first infection in May and the second in June were from separate occasions. Symptoms were more severe during the second infection. More

More than 815,000 deaths due to COVID-19 globally could be prevented by universal mask use between August 26, 2020 and January 1, 2021, based on recent IHME projections

Children with asthma or obesity who were hospitalized with SARS-CoV-2 were at increased risk for critical care admission or need for respiratory support.

The most common motivations for social distancing among survey respondents in North America and Europe were wanting to protect others, self-protection, and feeling a sense of responsibility to protect the community.

The BLAZE-1 clinical trial found that a combination of two monoclonal antibodies showed evidence of efficacy for treatment of mild-to-moderate COVID-19. These findings are based on a press release and have not been peer reviewed.

Lopinavir-ritonavir was not associated with a reduction in 28 day all-cause mortality, duration of hospital stay, or death in a randomized open-label trial (RECOVERY Trial).

Approximately three-quarters of people who required hospitalization for COVID-19 reported at least one lingering symptom or effect 3 months after their symptoms began. The most frequently reported effects were reduced quality of life (51%) and shortness of breath (50%).

A study of viral genomes from Washington State indicated that the timing of mitigation strategies and repeated introductions of viral lineages into the state likely shaped the relative distribution of different lineages of SARS-CoV-2, rather than differences in transmissibility between variants of the virus.

SARS-CoV-2 contact investigations in two Indian states showed the distribution of COVID-19 cases and deaths was younger than previously observed in the US, and is not explained by differences in underlying age of the populations. Risk of infection was higher among similar-age contacts, and most contacts who tested positive were exposed to an index case aged 20-44 years.

Among patients hospitalized with COVID-19 in the US, prior psychiatric diagnosis was associated with a higher mortality rate after controlling for demographic characteristics, other comorbidities, and hospital locations.

A university in North Carolina experienced 670 cases of COVID-19 within 2 weeks of reopening, likely due to student living arrangements and gatherings both on and off campus.

The prevalence of antibodies against SARS-CoV-2 was higher in US neighborhoods that have residents who predominantly identify as non-Hispanic Black or Hispanic and in more densely populated communities. Counties that reduced workplace visits by at least 5% in early March had lower antibody prevalence in July, 2020 compared to counties that did not reduce mobility.

Both surgical masks and KN95 masks reduce outward particle emissions during coughing (74% reduction) and speaking (90% reduction).

Key Takeaways: A modified SARS-CoV-2 PCR testing procedure that eliminated the bottleneck step of RNA extraction achieved high sensitivity and specificity.

Spending time in an emergency department at the same time as someone with COVID-19 did not appear to increase the risk of acquiring SARS-CoV-2 infection, based on a case-control study among 39 emergency departments in the western United States

Antibody testing of healthcare workers in Detroit found that 7% had antibodies against SARS-CoV-2 and that nurse assistants and nurses had higher likelihood of SARS-CoV-2 seropositivity than physicians. Consistent use of PPE, including N95 respirators and surgical facemasks, decreased the likelihood of seropositivity.

West Virginia nursing homes with higher quality ratings from the Centers for Medicare and Medicaid Services had up to 94% lower odds of experiencing a COVID-19 outbreak compared to nursing homes with the lowest quality ratings. More

One-quarter of the pregnant women who were hospitalized with symptomatic COVID-19 had a severe disease course, including ICU admission, mechanical ventilation, or death. More

Of the 121 SARS-CoV-2 associated deaths in the US among people <21 years old reported to the CDC by July 31, 70% were 10-20 years old and 10% were infants. People age <21 years made up 0.08% of all SARS-CoV-2 associated deaths. More...

A 3% prevalence of SARS-CoV-2 antibodies among 50,130 consecutive life insurance applicants in the US corresponds to an estimate of the total number of SARS-CoV-2 infections that is 3.8-times higher than the number of cases reported by the CDC. More

Twelve children who acquired SARS-CoV-2 in child care facilities in Utah transmitted the infection to at least 12 out of 46 (26%) non-facility contacts. More

Adults with a positive SARS-CoV-2 PCR test were twice as likely to have reported dining at a restaurant than were those with negative SARS-CoV-2 test results in a study at 11 US medical centers. More

Key Takeaways: Universal masking and universal SARS-CoV-2 testing for patients at admission decreased high risk exposures to SARS-CoV-2 among healthcare workers by 68% and 77%.

Key Takeaways: Non-randomized phase 1/2 studies in Russia of adenovirus recombinant vaccines, rAD5 and rAd26, were well tolerated with no serious adverse events with. All participants (n=38 per vaccine) produced antibodies to the vaccines, and humoral and cellular immune responses were strong

Key Takeaways: Patients who had a likely vitamin D deficiency were more likely to test positive for COVID-19 than those with sufficient vitamin D levels.

Key Takeaways: The recombinant nanoparticle vaccine NVX-CoV2373 induced higher anti-spike IgG and neutralizing responses compared to convalescent serum without serious adverse events.

Key Takeaways: A meta-analysis of 7 randomized trials (12 countries, 1,703 critically ill patients with COVID-19) found that patients receiving corticosteroids had lower 28-day all-cause mortality (OR=0.7, 95%CI 0.5-0.8) compared with usual care or placebo.

Key Takeaways: An outbreak of SARS-CoV-2 in China was linked to riding on a bus without outdoor air recirculation.

Key Takeaways: Serious adverse events were rare (<1%) among a sample of more than 20,000 patients with COVID-19 who received a convalescent plasma transfusion.

Key Takeaways: A cohort study of children admitted to hospitals in the UK with proven or highly-likely COVID-19 found that 11% of children met criteria for multisystem inflammatory syndrome, and that acute COVID-19 was associated with age < 1 month, age 10-14 years, and Black ethnicity.

Key Takeaways: N95 masks and similar KF94 masks worn by coughing patients with SARS-CoV-2 infection blocked the spread of viral RNA to surrounding surfaces considerably better than surgical masks.

Key Takeaways: Four overnight camps in Maine (1,022 attendees from 41 states) implemented multilayered prevention and mitigation strategies that were successful in identifying and isolating three asymptomatic persons with SARS-CoV-2 infection and in preventing secondary transmission.

Key Takeaways: Analysis of 772 SARS-CoV-2 genomes from Massachusetts identified more than 80 distinct introductions into the Boston area and a superspreader event among a highly mobile population that contributed substantially to community transmission.

Key Takeaways: Jails and prisons in Massachusetts report an incidence of COVID-19 that is 2.9-fold higher than among the Massachusetts general population and 4.8-fold higher than the US general population.

Key Takeaways: Immunologic examinations of 15 people who had recovered from mild COVID-19 found evidence of SARS-CoV-2-specific immune markers that the authors believe provide evidence that recovered individuals will be protected from a second SARS-CoV-2 infection.

Key Takeaways: Mass testing conducted in 16 prisons and jails from 6 US jurisdictions found a median prevalence of 29% and a median 12-fold increase in SARS-CoV-2 cases identified in facilities compared to earlier symptom-based testing.

An assessment of 2 likely SARS-CoV-2 transmissions on an international flight among 102 total passengers with 7 potential index cases suggests possible airborne transmission.

An analysis of COVID-19 hospitalizations across 12 US states found that the share of hospitalizations of white patients was substantially smaller than the corresponding share of the states’ populations, and the share of hospitalizations among Black and Hispanic patients was substantially larger.

Utah reported 1,389 COVID-19 cases associated with 210 workplace-related outbreaks during March 6–June 5, 2020, which occurred most commonly in the areas of manufacturing (20%), construction (15%), and wholesale trade (14%). Hispanic and nonwhite workers accounted for a large disproportional number of workplace outbreak-associated COVID-19 cases.

A nationally-representative study in England found broad acceptability and reliability of results from home-based self-testing for SARS-CoV-2 antibodies, but found some challenges with the usability of the evaluated kits.

The mean daily COVID-19 incidence rate decreased 4 days after implementation of statewide physical distancing measures in the US, with a decrease of 1% per day, according to a time series analysis. COVID-19-attributed mortality rates decreased 7 days after measures were implemented by 2% per day.

The filtration efficiency of properly-fitted expired and sterilized N95 masks was found to exceed 95%. The filtration capacity of other face mask alternatives commonly used in healthcare settings ranged from 38% to 83%.

Employees of a New York City hospital had a considerably lower seroprevalence of SARS-CoV-2 antibodies (10%) compared to general population estimates for New York City (21%) and Long Island (17%).

Survey results suggest that while Americans have more privacy and security concerns regarding the use of digital contact tracing apps compared to citizens of other countries, more than 68% would still be willing to use such an app on their phone.

Viral shedding was similar between asymptomatic and symptomatic patients with SARS-CoV-2 infection in a South Korean cohort, with similar rates of conversion to a negative RT-PCR result over time. Most patients (75% asymptomatic vs. 70% symptomatic) had a negative RT-PCR test by 21 days after diagnosis.

An analysis using SARS-CoV-2 viral cultures found that all culture-positive specimens (16/68) were obtained within the first 8 days after symptom onset, despite RNA detection up to several weeks after symptom onset, suggesting that patients may be less infectious after a period of approximately 8 days.

SARS-CoV-2 transmission in schools and childcare facilities in New South Wales, Australia, demonstrated higher attack rates from adult cases than child cases, for both transmission to child and adult contacts.

During the first month of the COVID-19 pandemic in 5 states in the US, there was a decrease (range 42%-64%) in emergency department (ED) visits, but an increase in hospital admission rates from the ED (range 22%-149%), indicating a lower overall volume but higher overall acuity of illness in ED visits occurring during the COVID-19 pandemic.

An outbreak of SARS-CoV-2 at an overnight camp in Georgia resulted in 260 confirmed infections among 597 attendees, with an overall attack rate of 44% and high attack rates in all age groups of children and young adults.

Children younger than 5 years old had 10- to 100-fold higher levels of SARS-CoV-2 RNA in their nasopharynx compared with older children and adults.

School closures were associated in time with declines in COVID-19 incidence (-62%) and mortality (-58%) across US states, although at least some of the effect may have been due to other non-pharmaceutical interventions implemented concurrently.

SARS-CoV-2 testing among household contacts of COVID-19 cases in Wisconsin and Utah found a 20% attack rate among contacts under age 18 years and 26% among those 18 years or older.

Analysis of PCR test results from a national reference laboratory found that the median age of people testing positive for SARS-CoV-2 in the US has declined from 41 years in April-May to 36 years in June-July.

A county-level study of the US found that nearly all counties that achieved a 70% reduction in visits to non-essential businesses brought the effective reproduction number (Rt) below 1.

Residents in long-term care facilities in Ontario, Canada had a 13-fold higher risk of death from COVID-19 compared to community-living adults age 70 and older.

Based on transmission pairs in China, the time between the onset of symptoms in the initially infected individual and symptom onset in the person they infected decreased over time, which may have been due to the implementation of policies for rapid isolation of people with symptoms of COVID-19.

A seroprevalence study in Blaine County, Idaho, a resort community with a high incidence of COVID-19 in March and April, found nearly a quarter of residents were positive for SARS-CoV-2 antibodies.

A recombinant adenovirus type-5-vectored candidate vaccine currently in phase 2 testing showed strong antibody and T-cell response and no evidence of serious adverse reactions.

Based on simulation models informed by measurements of exhaled aerosol particles, risk of aerosol transmission depends both on emitter behavior (speaking versus normal breathing) and ventilation systems. The location of ventilation in lecture halls and grocery stores could affect transmission risk.

A modeling study suggests that Seattle could return to full workplace and community mobility without loss of COVID-19 epidemic control in a scenario that includes high mask compliance, school closures, high levels of testing, and tracing of half of all contacts within 2 days.

A phase 1, dose-escalation, open-label trial of the candidate vaccine mRNA-1273 among 45 healthy adults found that all participants had serum neutralizing antibody activity after the second vaccination. No trial-limiting safety concerns were identified.

Surveys among representative US samples found that self-reported use of a cloth face covering when in public was reported by 62% of respondents in April, immediately after the White House Coronavirus Task Force and CDC recommended this practice, and increased to 76% one month later. Reported use of a face covering was more common among non-Hispanic white persons, those aged ≥65 years, and those residing in the Midwest.

A review article concludes that the probability of transmission from wastewater is low, but that monitoring of wastewater may be used to detect early signs of an outbreak.

There is evidence of increased incidence of stress cardiomyopathy among COVID-19-negative individuals compared to pre-pandemic time periods, which could be linked to increases in psychological and economic distress.

The COVID-19 case rate of 3,251 per 100,000 among US prisoners was 5.5-times higher than the US population case rate of 587 per 100,000 persons.

Following the re-opening of nightclubs in South Korea, 246 COVID-19 cases were linked to a single outbreak in a nightclub in Seoul during a week-long holiday. This suggests that superspreading events related to nightclubs have the potential to spark a resurgence of cases.

Loosely folded face masks and bandana-style face coverings provided minimal stopping effect for the smallest aerosolized respiratory droplets in emulated coughs and sneezes, while well-fitted homemade masks with multiple layers of quilting fabric and off-the-shelf cone style masks were effective in reducing droplet dispersal.

Loosely folded face masks and bandana-style face coverings provided minimal stopping effect for the smallest aerosolized respiratory droplets in emulated coughs and sneezes, while well-fitted homemade masks with multiple layers of quilting fabric and off-the-shelf cone style masks were effective in reducing droplet dispersal.

A meta-analysis of 10 studies (9,890 subjects) found no significant association between using ACE inhibitors or angiotensin receptor blockers and the risk of severe or lethal COVID-19.

The daily incidence of COVID-19 cases among adults aged 20-59 years and ≥60 years increased in Florida soon after the full Phase 1 reopening went into effect.

Patient-collected lower nasal specimens had diagnostic equivalence to healthcare worker-collected lower nasal and oropharyngeal specimens for detection of SARS-CoV-2 by RT-PCR.

Only 27% of Colorado residents who tested positive for SARS-CoV-2 prior to the March 26 stay-at-home order reported a known contact with a confirmed COVID-19 case, another 30% had contact with a person with fever or respiratory symptoms, and the remaining 43% reported no known contacts. The most common potential exposures were gatherings of >10 people, domestic travel, working in or visiting a health care setting, and using public transportation.

A seroprevalence survey from six US states and regions found seroprevalence in serum collected for routine clinical purposes ranged from 1.1% to 7.9%. The authors concluded that in five out of the six US sites, there have been >10-times more SARS-CoV-2 infections than cases reported.

Based on the experience of 4 European countries, there is some evidence that school closures led to declines in the epidemic growth rates of COVID-19. Reopening of schools for all students in countries with low community transmission (Denmark and Norway) has not resulted in a significant increase in the growth rate of COVID-19 cases. Return of most students to school in countries with higher levels of community transmission (Germany) has been accompanied by increased transmission among students, but not school staff.

An online survey of a nationally representative US sample found that the level of perceived risk of contracting and dying from COVID-19 was positively associated with health behaviors like handwashing and social distancing.

A college spring break trip resulted in SARS-CoV-2 infection in 60 (28%) college-aged travelers and their contacts included in the outbreak investigation, one-fifth of whom were asymptomatic at the time of testing.

Surgical mask use reduced the proportion of droplets and aerosols with detectable virus among patients infected with seasonal coronavirus and influenza virus, but not among those with rhinovirus infection (common cold).

Asymptomatic people with SARS-CoV-2 infection had a longer duration of viral shedding and lower virus-specific IgG levels than a comparison group of people with symptoms, suggesting that they may have a weaker immune response to SARS-CoV-2 infection.

A composite test for both SARS-CoV-2 virus and antibodies shows promise for rapid diagnosis with high test validity.

A genome-wide association study identified two separate loci associated with genetic susceptibility to severe COVID-19 disease. One of the loci coincides with the ABO blood group locus. The genetic results found blood group O was associated with lower risk of COVID-19 while blood group A was associated with higher risk of severe disease.

High-resolution spatiotemporal approaches may provide an alternative to digital contact tracing for cluster detection and monitoring, potentially reducing privacy concerns.

A study from Japan found that symptom-based testing of travelers missed most prevalent cases of SARS-CoV-2 at entry. Even with universal screening, nearly half of cases would have been missed without repeated testing over a 14-day period.

A comparison between nasal specimens and standard nasopharynx swabs found high concordance (Cohen’s kappa >0.8) for the detection of SARS-CoV-2 among patients with viral loads >1000 copies/mL. Those with viral loads <1000 copies/mL had low concordance between sample types (Cohen’s kappa = 0.49).

Phylodynamic analyses suggest four genetic clusters are responsible for the major outbreaks of COVID-19 globally.

Boston, Massachusetts implemented a citywide COVID-19 care model for people experiencing homelessness. A large shelter outbreak during the third week of operations illustrated the need to adapt the model to universal testing and to increase capacity to shelter people experiencing homeless with COVID-19.

The average time to transition from RT-PCR positive to negative for patients and healthcare workers at a US academic medical center was 24 days after symptom onset.

Stay-at-home orders were associated with decreases in reports of robberies and traffic stops and increases in domestic violence calls in Los Angeles and Indianapolis.

According to the CDC, non-pharmaceutical interventions successfully contained SARS-CoV-2 among recruits in a Basic Military Training setting at a US Air Force base.

A randomized trial of convalescent plasma to treat cases of “severe” and “life-threatening” COVID-19 in Wuhan, China found no significant difference in time to clinical improvement within 28 days. However, the study was stopped early and was insufficiently powered for the primary outcomes. Though non-significant, the findings showed promising trends for efficacy, particularly among those with “severe” as opposed to “life-threatening” disease.

Today, researchers at the University of Minnesota published results from the first randomized clinical trial of hydroxychloroquine as post-exposure prophylaxis (PEP) for COVID-19. The study found no differences between hydroxychloroquine and placebo in preventing SARS-CoV-2 infection.

A discrete-choice experiment focusing on COVID-19 risk and the tradeoffs inherent in mitigation strategies reveals that US adults fall into four distinct categories predicted by political affiliation, race, household income and employment status.

Better ventilation substantially reduces the amount of time respiratory droplets are airborne. This has potential implications for recommendations regarding avoidance of poorly ventilated public spaces and for hospitals to improve ventilation in settings where aerosolization by coughing and close contact with COVID-19 patients is common.

Four separate lines of evidence point to sustained community transmission of SARS-CoV-2 within the US beginning in late January and early February, weeks before the first non-travel-related cases were detected. A separate phylogenetic study concluded that the first SARS-CoV-2 case identified in Washington State in January 2020 is not linked to outbreaks that occurred weeks later, and that the rapid public health response may have prevented an earlier potential outbreak.

A randomized trial found comparable outcomes for 5-day and 10-day courses of remdesivir for hospitalized COVID-19 patients.

Salivary antibodies to SARS-CoV-2 mirror serum antibody responses, indicating that oral antibody testing could be a non-invasive alternative to serological testing to enable widespread monitoring of SARS-CoV-2 infection throughout the population.

A double-blind randomized trial found that remdesivir use in hospitalized adult COVID-19 patients results in faster recovery. There was non-significant evidence of lower mortality by 14 days.

Protective immunity against the spike glycoprotein, the target of many vaccines currently entering clinical trials, was detected after mild to moderate SARS-CoV-2 infection.

SARS-CoV-2 infection induced protective immunity against re-infection in nonhuman primates.

Based on a fluid particle dynamics model of the behavior of droplets released from the cough of an infectious person, the social distancing policy of 6 feet may not be sufficient under some wind and relative humidity conditions.

The probability of a false negative SARS-CoV-2 RT-PCR test result varies significantly over the disease course. The false negatives rate was lowest between symptom onset (38%) and3 days following symptom onset (20%). The probability of receiving a false negative test result may be as high as 67% on the day prior to symptom onset.

There is no evidence that RAAS inhibitors increase the risk of severe COVID-19 disease. The authors recommend that these medications should not be discontinued in an attempt prevent severe cases of COVID-19.

Models show that even the most efficient contact tracing strategies are not sufficient to bringing the effective reproduction number (R) to below 1 if there are testing delays as short as 4 days. App-based contact tracing, even with coverage as low as 20%, may be superior to conventional contact tracing.

State-wide school closures are associated with fewer COVID-19 cases and deaths per capita. State-wide deaths due to COVID-19 were estimated to be 12% higher for each additional day that schools remained open.

Salazar et al. report safety and improved clinical status among 25 patients with severe COVID-19 after transfusing convalescent plasma from donors with confirmed SARS-CoV-2 infection.

An age-stratified model calibrated Seattle, Washington showed early implementation of social distancing interventions would delay the epidemic curve, while later implementation flattened it. The model indicated that the epidemic would rebounded after cessation of social distancing if testing and contact tracing were not performed.

Syndromic screening of air-travelers at exit or entry and broad communication about COVID-19 symptoms following their arrival has likely delayed the local spread of SARS-CoV-2.

An analysis of smartphone location data and healthcare and economic indicators reveals a strong association between greater declines in mobility in counties that are healthier and wealthier, indicating a social distancing privilege gap.

The COPE Consortium has developed a COVID-19 Symptom Tracker mobile application. User self-report of symptoms through this app can be used to identify COVID-19 hotspots.

SARS-CoV-2 could remain stable at 37°C for at least 24 hours, but heating at 56°C for 30 minutes could effectively inactivate the virus while preserving the stability of viral RNA in both human sera and sputum samples.

Modeling studies that examined national and local (King County) COVID-19 epidemics found that relaxation of social distancing strategies prior to June 2020 could trigger a second wave of infections.

Repeated universal testing (for instance, via mailed home testing kits) with isolation of infectious individuals can reduce transmission sufficiently to halt the epidemic, even with a false negative test rate of up to 15%

Detection of SARS-CoV-2 RNA in the blood is strongly associated with severe disease (ICU hospitalization 32% v. 14%; mechanical ventilation 21% v. 4%) and increased mortality among COVID-19 patients (14% v. 0%) compared to patients without detectable RNA.

Findings from a systematic review do not support claims that most SARS-CoV-2 infections are asymptomatic, estimating that only about 29% of infections remain asymptomatic throughout the course of infection.

Waste water based epidemiology is a sensitive tool that can be used to monitor spatial and temporal trends of SARS-CoV-2 virus circulation in the population.

Barkan et al compares various exit strategy building blocks and measures to mitigate the current SARS-CoV-2 pandemic based on computerized simulations, finding significant differences in suppression among strategies with seemingly similar cost.

Vertical transmission of SARS-CoV-2 infection from mothers affected by COVID-19 during the last days of pregnancy is possible but relatively infrequent.

The downward trend of IgG during recovery may indicate limited duration of acquired immune protection

Modeling studies continue to highlight the dangers of lifting or relaxing social distancing policies too soon, and suggest a longer-term initial period of restrictive social distancing coupled with a gradual reduction in the severity of social distancing as being more effective.

Models suggest using controlled avalanche strategy to achieve herd immunity faster and with lower mortality rates. This strategy reduces overall mortality and ICU admissions by 43 and 62% respectively.

Multiple studies evaluate the effectiveness of non-pharmaceutical interventions. While border closures, quarantine policies and business closures were generally associated with reduced SARS-CoV-2 (and, in one study, influenza) transmission, school closures were noted as the least effective intervention.

Another study finds no mother-to-child transmission of SARS-CoV-2 during breastfeeding, and suggests that the benefits of breastfeeding may outweigh the risk of infection.

One modeling study suggests that a strict restriction on seniors combined with gradual lifting of quarantine for the general population may be a good strategy to limit COVID-19 related deaths while lessening economic damage, and another recommends the country re-open in late May or early June.

Studies to determine efficacy of therapeutic treatments continue- one suggesting that convalescent plasma may be effective and specific for COVID-19, while another suggesting that RAS inhibitors could improve clinical outcomes of COVID-19 patients with hypertension.

National BCG vaccination is correlated with protection from death from COVID-19, potentially due to non-specific “trained immunity” mediated by this vaccine.

Multiple mathematical models use past data from Italy, China, and the US to evaluate the success of previously implemented public health approaches and make recommendations about future social distancing.

Though not considered an aerosol generating procedure, persons giving birth exert extreme effort and frequently blow outwards, cough, shout, and vomit, all of which put the health care team at risk of exposure to COVID-19.

Research continues on refining and improving current testing capabilities, and one study suggests that self-collected throat washings may present a better SARS-CoV-2 sampling method.

A testing protocol that has the potential to dramatically reduce the cost and complexity of population scale testing is proposed by Schmidt et al.

Two recent studies suggest a link between BCG vaccination policy and the morbidity and mortality due to COVID-19. They conclude that universal BCG vaccination may have protective effect on the course of COVID-19, probably preventing progression to severe disease and death.

A new study questions the effectiveness of surgical and cotton masks in blocking cough droplets from SARS-CoV-2 infected patients.

Genetic sequencing of SARS-CoV-2 samples suggests that the virus was circulating in Washington State 4-6 weeks before the first community-acquired case was detected on February 28.

Local health departments can potentially use sentinel surveillance to understand the level of community transmission of COVID-19.

Multiple reports discuss optimal timing and implementation of social distancing and lockdown measures and their potential impacts on geographic spread.

Cigarette smoke triggers the expansion of a subpopulation of respiratory epithelial cells that express the SARS-CoV-2 receptor ACE2, an explanation for why smokers develop severe COVID-19.

A study on transmission of SARS-CoV-2 in a public bath center in China found that transmission can still arise in an environment with high temperature and humidity.

Whilst COVID-19 is mild disease in children, data available to date suggests that children have not played a substantive role in intra-household transmission of SARS-CoV-2.

Multiple studies confirm the presence of antibodies to SARS-CoV-2 in neonates born to mothers with COVID-19 suggesting possible vertical transmission.

A free online tool that is capable of estimating the maximum daily number of incident COVID-19 cases that a healthcare system could manage given age-based distribution and severity is shared in a study.

Multiple studies suggest gastrointestinal or fecal-oral route for SARS-CoV-2 transmission.

Several studies provide treatment recommendations for COVID-19 patients with severe acute respiratory distress syndrome.

While highly disruptive to society, a study found four social distancing interventions to be highly effective in flattening the curve, even after a 10-week delay from index case arrivals.

Results from a meta-analysis highlight the importance of timely and clear communication by public health officials for better quarantine adherence.

A study highlights the significance of large-scale and standardized clinical testing for early prevention and control of COVID-19.

Prisons, youth detention centers and immigration detention centers are high-risk settings for COVID-19 outbreaks and should be integrated in COVID-19 public health responses.

Similar to prior studies, a new study found no evidence of vertical transmission of SARS-CoV-2.

More studies emphasize the importance of self-imposed prevention measures and social distancing to curb the spread of COVID-19.

More research is exploring transmission routes for COVID-19, emphasizing fomite spread and possible aerosolization in confined spaces.

One study calls attention to clinical recommendations during the current outbreak for psoriasis patients who may be on immunosuppressive treatments.

There is new evidence indicating stability of SARs-CoV-2 on surfaces and in the air, supporting plausible fomite and aerosol transmission of COVID-19.

Several new studies have explored the potential efficacy of treatments for other conditions that have been FDA-approved and may have useful applications for COVID-19 patients, though further study and clinical trials are warranted. Among those discussed in the newest literature are cepharanthine (CEP), selamectin, mefloquine hydrochloride, and chloroquine phosphate.

The effectiveness of non-pharmaceutical interventions depends on a number of factors, including public health capacity for intervention implementation and enforcement, disease serial interval, and the level of pre-symptomatic transmission.

New age-specific case fatality estimates from Hubei Province show a sharp incline in case fatality after age 60, reaching 36% among those aged 80 and older compared to just 3.3% (2.9-2.8) among symptomatic cases and only 1.6% (1.4-1.8) across symptomatic and asymptomatic cases combined.

Two articles have outlined specific recommendations for managing gynecological and obstetric care for pregnant women diagnosed with COVID-19.

Another study of the potential for sexual transmission of COVID-19 has found no evidence of vaginal transmission, though more research is needed to confirm.

Several studies in recent days have explored the possibility of antibody screening as an alternative or supplemental diagnostic test for COVID-19. Results have been largely promising, especially for combined RT-PCR and antibody testing.

Descriptive studies of fatal COVID-19 cases continue to converge on key factors that appear to be associated with an elevated risk of death: older age, male sex, and comorbidities (e.g., hypertension, heart disease, and diabetes).

Testing methodologies continue to be evaluated for sensitivity and specificity, especially in relation to disease stage and severity. One new study found that the presence of viral RNA in blood and anal swabs is associated with severe disease.

There remains no evidence that SARS-CoV-2 can be transmitted sexually.

New studies continue to find that older age and comorbidities, especially hypertension, are associated with an elevated risk of COVID-19 illness, increased symptom severity, and death.

Increasingly, modelling papers suggest that the movement restrictions implemented in Wuhan on January 25th appear to have had an impact on the rate of spread outside of Hubei Province.

Mounting evidence from small family cluster and larger population studies suggests not only a strong likelihood of asymptomatic transmission of SARS-CoV-2 but also that cases resulting from asymptomatic transmission can develop severe illness.

Preliminary evidence from hospital-based studies indicates that kidney impairment and acute respiratory distress syndrome are associated with a greater likelihood of death among hospitalized COVID-19 patients.

Two articles discuss the potential effectiveness of Chloroquine phosphate as a viable treatment option for COVID-19-associated pneumonia.

New efforts to predict how long the outbreak will last appear to disagree substantially, highlighting the importance of interpreting any such predictions with caution.

Several new papers have used modelling and prediction techniques to assess the pandemic potential of COVID-19, exploring the effectiveness of travel restrictions and other infection control measures. On their own, environmental conditions (e.g., seasonality and humidity changes) appear unlikely to slow the spread of the outbreak.

Clinicians and researchers continue to share recommendations for COVID-19 patient screening and care based on current experience and lessons learned from prior coronavirus outbreaks. 

Accounting for underreporting, new statistical modelling efforts indicate that there may have been closer to 100,000 COVID-19 cases in China before the end of January compared to official estimates under 20,000.

2019-nCoV Case Fatality Rates have a broad range, depending on age, severity of illness at time of diagnosis, and sex. A calculated CFR for hospitalized patients ranges from 0.7% for those presenting with mild illness 9.5% for patients with two of three risks mentioned.

The possibility of asymptomatic transmission remains an open question.

A descriptive study of 1,099 2019-nCoV patients in China offers some of the most robust information about clinical characteristics available. 

Pediatric patients appear to experience milder illness and often exhibit no obvious symptoms at time of diagnosis.

Persons testing positive for 2019-nCoV with mild or no symptoms have been found through investigation of family clusters in multiple countries. 

Researchers continue to conclude that bats are the most likely evolutionary predecessor to 2019-nCoV, though there remains no agreement on precisely how the jump may have occurred.

Despite a flawed earlier report, asymptomatic transmission has not been confirmed in peer-reviewed literature.

Implications of 2019-nCoV recognition of the human cell receptor angiotensin converting enzyme II (ACE2) is a hot topic, with researchers considering everything from potential therapies to novel transmission mechanisms based on this information.

A second case of 2019-nCoV was identified in Germany resulting from apparent asymptomatic transmission from an infected Chinese traveler. 

The first case of person-to-person transmission in the U.S. was reported in Chicago today. 

Estimates of R0, incubation period, and illness duration are still inconsistent as researchers rely on a range of case reporting sources. Even so, some patterns are beginning to emerge and may be worth noting, with caution.

There is increasing evidence for person-to-person transmission both in and outside of China.