Result for
Topic: Vaccines and Immunity
March 25, 2021
BNT162b2 MRNA Covid-19 Vaccine Effectiveness among Health Care Workers
Weekly incidence of COVID-19 among healthcare workers (HCWs) in a two-campus medical center in Jerusalem steadily declined after commencement of two-dose vaccinations with the Pfizer-BioNTech vaccine in December 2020. Decline in incidence occurred despite a surge of the B.1.1.7 variant (up to 80% of cases) within the community. Benenson et al. (Mar 23, 2021). BNT162b2 MRNA…
March 23, 2021
Association of Age With SARS-CoV-2 Antibody Response
SARS-CoV-2 antibody responses are distinct in different age groups, according to a cross-sectional study of a New York City hospital using 31,426 SARS-CoV-2 antibody test results from pediatric and adult patients. IgG levels were negatively correlated with age in the pediatric population (r = -0.45, P < .001), but moderately positively correlated with age in…
Exposure to SARS-CoV-2 Generates T-Cell Memory in the Absence of a Detectable Viral Infection
Exposure to SARS-CoV-2 may still lead to the development of SARS-CoV-2-specific memory T cells in the absence of detectable SARS-CoV-2 virus or antibodies against SARS-CoV-2 antigens (spike and nucleocapsid). In blood samples collected from 69 individuals between 48 and 86 days after close contact with an individual with a confirmed SARS-CoV-2 infection, 58% and 14%…
Reduced Neutralization of SARS-CoV-2 B.1.1.7 Variant by Convalescent and Vaccine Sera
The B.1.1.7 variant has a 7-fold higher binding affinity to the angiotensin converting enzyme-2 (ACE2) receptor in human cells than a parent SARS-CoV-2 strain isolated from Wuhan, suggesting a mechanism for the rapid emergence of this variant. Serum from individuals vaccinated with either the Pfizer-BioNTech or the Oxford-AstraZeneca and serum recovered from infection with the…
Risk of Reinfection after Seroconversion to SARS-CoV-2 A Population-Based Propensity-Score Matched Cohort Study
[Pre-print, not peer-reviewed] Swiss adults who were seropositive for SARS-CoV-2 IgG antibodies were less likely to have a SARS-CoV-2 PCR positive test than propensity-score-matched seronegative adults in the 8 months following antibody measurements. Of the 498 seropositive individuals, only 5 (1%) retested positive (likely indicative of reinfection) after a mean follow-up of 36 weeks. In…
Reduced BNT162b2 MRNA Vaccine Response in SARS-CoV-2-Naive Nursing Home Residents
[Pre-print, not peer-reviewed] Nursing home (NH) residents had blunted antibody responses following vaccination with BNT162b2 mRNA vaccine (Moderna) when compared to healthcare workers. SARS-CoV-2-naive NH residents mounted antibody responses with nearly 4-fold lower median neutralization titers and half the anti-spike level compared to SARS-CoV-2-naive healthcare workers. In contrast, NH residents who had recovered from infection…
March 19, 2021
Neutralizing Antibodies Against SARS-CoV-2 Variants After Infection and Vaccination
Neutralizing antibody activity against four SARS-CoV-2 variants, including B.1, B.1.1.7, and N501Y was maintain in sera from individuals with infection- and vaccine-induced antibodies. There was minimal reductions in serum neutralization observed across four representative SARS-CoV-2 strains. Serum was obtained from adults (n=20) hospitalized with COVID-19 5 to 19 days after symptom onset, convalescent individuals (n=2)…
March 18, 2021
Assessment of Protection against Reinfection with SARS-CoV-2 among 4 Million PCR-Tested Individuals in Denmark in 2020: A Population-Level Observational Study
Individuals with a positive SARS-CoV-2 PCR test during the first surge in Denmark (prior to June 2020) were less likely to get a positive test during the second surge (September to December 2020) compared to individuals with a negative SARS-CoV-2 PCR test during the first surge. In this nationwide cohort study (n=525,339), 72 of 11,068…
March 17, 2021
County-Level COVID-19 Vaccination Coverage and Social Vulnerability — United States, December 14, 2020–March 1, 2021
Counties with high social vulnerability had lower first-dose vaccination coverage (14%) compared to those with low social vulnerability (16%) during the first 2.5 months of the SARS-CoV-2 vaccination program in the US (December 15, 2020 – March 1, 2021). Vaccination coverage was lower in low vulnerability counties compared to high vulnerability counties among those aged…
Associations of the BNT162b2 COVID-19 Vaccine Effectiveness with Patient Age and Comorbidities
[Pre-print, not peer-reviewed] Effectiveness of the Pfizer-BioNTech vaccine gradually increased starting at 12 days after the first vaccine dose and then plateaued around 35 days, according to an analysis of electronic health records from 1.79 million individuals in Israel. This period of maximum effectiveness corresponds to a period 2-weeks after the scheduled administration of the…
Previous page Next page