Result for
Topic: Transmission
May 8, 2020
Clinical Characteristics and Results of Semen Tests Among Men With Coronavirus Disease 2019
Li et al. tested semen samples from 38 patients with COVID-19 and detected SARS-CoV-2 from 6 patients (15.8%), including 4 of 15 patients (26.7%) who were at the acute stage of infection and 2 of 23 patients (8.7%) who were recovering. Future studies are needed to determine if SARS-CoV-2 can be sexually transmitted and whether abstinence or condom use should be considered as…
Viral Kinetics of SARS-CoV-2 in Asymptomatic Carriers and Presymptomatic Patients
Kim et al. included 71 participants with laboratory-confirmed SARS-CoV-2 infection who were hospitalized for treatment or isolation and found that 3 were pre-symptomatic and 10 were entirely asymptomatic. Two of the three pre-symptomatic patients had very high levels of virus present during the incubation period (Ct value <20). The median time until the first negative RT-PCR (Ct >35) in the entirely asymptomatic carriers was 4.5 (range 2.5-9) days, and all asymptomatic…
May 7, 2020
Internet Search Patterns Reveal Clinical Course of Disease Progression for COVID-19 and Predict Pandemic Spread in 32 Countries
Analysis of global internet search patterns in 32 countries across six continents detected a robust temporal pattern of a progression of search terms related symptoms that matches the clinical course of COVID-19. Earliest-peaking search terms were combinations of “fever”, “cough”, “coronavirus symptoms”, and “coronavirus test.” There was an average lag of 5-days between increases in searches for “fever” and “cough” and the increase in searches…
Effect of Temperature on the Transmission of COVID-19 A Machine Learning Case Study in Spain
Using a machine learning approach, authors in three populous regions in Spain found a small inverse association between temperature and daily number of COVID-19 infections, and that this association persisted for lags of up to 6 days, corresponding to the mean incubation period for COVID-19. No evidence of association with humidity or wind speed was found. Abdollahi et al. (May…
May 6, 2020
A Simple Method for Estimating the Number of Unconfirmed COVID-19 Cases in a Local Area that Includes a Confidence Interval: A Case Study of Whatcom County Washington
Swanson and Cassman estimate the number of positive, unconfirmed COVID-19 cases in Whatcom County, Washington and construct a confidence interval around the estimate, using a previously established method employed by demographers to estimate a population in the absence of a census count. On April 25, 2020, when Whatcom County had reported 284 confirmed cases, the authors estimate that…
SARS-COV-2 was already spreading in France in late December 2019
Deslandes et al. report the retrospective identification by RT-PCR of a patient with SARS-CoV-2 in Paris in December 2019. The patient hospitalized in December 2019 for hemoptysis with no etiological diagnosis. SARS-CoV-2 RNA was detected in a stored respiratory sample. Based on this result, it appears that SARS-CoV-2 was already spreading in France in late December 2019, a month before the official first cases…
May 5, 2020
Effects of Temperature and Humidity on the Daily New Cases and New Deaths of COVID-19 in 166 Countries
Wu et al. apply a statistical model to investigate temperature and relative humidity as predictors of new COVID-19 cases and deaths in 166 countries (excluding China) through March 27, 2020. They control for wind speed, median age of the national population, Global Health Security Index, Human Development Index, and population density as potential confounders. Temperature and relative humidity were both inversely associated with new cases and deaths. These findings provide preliminary evidence that…
Coronavirus in Water Environments: Occurrence, Persistence and Concentration Methods – A Scoping Review
Rosa et al. conduct a literature review and identify 12 studies of Coronaviruses (CoV) in water environments and evaluated implications for human health. Included studies suggest that: 1) CoV seems to have a low stability in water and is very sensitive to oxidants like chlorine; 2) CoV appears to be inactivated significantly faster in water than non-enveloped human enteric viruses with known waterborne transmission; 3) temperature…
May 4, 2020
Direct Observation of Repeated Infections with Endemic Coronaviruses
Galanti and Shaman demonstrate that reinfections with the same endemic coronaviruses (HKU1, 229E, NL63, and OC43) are not unusual within a >1 year time window. Analyzing data collected through proactive sampling (nasal swab and self-report) in NYC from fall 2016 to spring 2018, 12 out of the 191 participants experienced one or more reinfection, with time of reoccurrence ranging…
Estimation of SARS-CoV-2 Emissions from Non-Symptomatic Cases
Previous studies have shown high levels of SARS-CoV-2 in swab and sputum samples from individuals with no or mild symptoms of COVID-19. The authors modeled the airborne concentration of SARS-CoV-2 in a room the size of a small office or examination room using data on the distribution of aerosol sizes in exhaled breath generated by coughing…
Previous page Next page