Result for
Tag: immunity
January 29, 2021
Duration of SARS-CoV-2 Sero-Positivity in a Large Longitudinal Sero-Surveillance Cohort The COVID-19 Community Research Partnership
[Pre-print, not peer-reviewed] Follow-up of 11,468 adults with mild or asymptomatic COVID-19 infection found that serological evidence of previous infection, specifically the presence of either IgG or IgM antibodies, waned quickly over time, with roughly 50% of people undergoing sero-reversion within 30 days of their initial positive test. The rate of sero-reversion was not associated…
January 28, 2021
Neutralization of Spike 6970 Deletion E484K and N501Y SARS-CoV-2 by BNT162b2 Vaccine-Elicited Sera
[Pre-print, not peer-reviewed] Sera from recipients who completed the 2-dose regimen of the Pfizer vaccine BNT162b2 (n=20) had similar neutralizing geometric mean titers (GMTs) against SARS-CoV-2 viruses engineered to contain key spike protein mutations from variants emerging from the UK (B.1.1.7) and South Africa (B.1.351) compared to GMTs against the wild-type virus. Compared to the…
U.S. Public Views about COVID-19 “Immunity Passports
[Pre-print, not peer-reviewed] A nationally representative online survey of 1,315 US adults conducted in June 2020 found that 45% of respondents supported some form of immunity privileges. Among the forms, private certificates were favored over government-issued immunity passports (48% vs 43%). Respondents were more likely to justify immunity privileges for high-risk jobs or to attend…
Resurgence of COVID-19 in Manaus, Brazil, despite High Seroprevalence
Despite a high SARS-CoV-2 seroprevalence of 76% among blood donors in Manaus, Brazil by October 2020, the area experienced a sudden rise in COVID-19 hospitalizations from 552 in December 2020 to 3,431 in January 2021. The authors suggest possible explanations for the resurgence in this setting where seroprevalence was higher than common estimates of the…
January 27, 2021
SARS-CoV-2 Serology Levels in Pregnant Women and Their Neonates
A study of the serologic response to SARS-CoV-2 infection in pregnant women (n = 88) found that asymptomatic pregnant women mounted a lower immune response than symptomatic pregnant women, and that maternal IgG antibodies were positively correlated with levels in neonates. Maternal IgM and IgG levels peaked around 15 and 30 days after onset of…
SARS-CoV-2 Recruits a Haem Metabolite to Evade Antibody Immunity
A molecular study of SARS-CoV-2 found that the virus’s spike protein was able to bind to biliverdin and bilirubin, products of heme metabolism. The authors identified the phenomenon after observing a green pigment in protein precipitate of recombinant SARS-CoV-2 spike produced in human cell lines. Binding to biliverdin inhibited the ability of immune sera and…
Non-Congruent SARS-CoV-2 Waves in England
A study of SARS-CoV-2 infection waves in England noted different regional distributions of infections during the first (March-September 2020) and second (September 2020-onward) waves, with regions that experienced high mortality in the first wave experiencing lower mortality in the second. Greater first wave severity was also associated with slower second wave growth rate. Possible explanations…
Kinetics and Correlates of the Neutralizing Antibody Response to SARS-CoV-2Kinetics and Correlates of the Neutralizing Antibody Response to SARS-CoV-2Kinetics and Correlates of the Neutralizing Antibody Response to SARS-CoV-2
[Pre-print, not per-reviewed] A longitudinal study of people who had recovered from COVID-19 (n=963) estimated a half-life of 7.7 months for anti-spike IgG and a half-life of 8.7 months for serum neutralization, with only 13% of individuals losing seroreactivity at ten months. In addition, around 3% of recovered patients demonstrated effective cross-neutralizing IgG antibodies to…
January 26, 2021
Longitudinal Analysis of Humoral Immunity against SARS-CoV-2 Spike in Convalescent Individuals up to 8 Months Post-Symptom Onset
[Pre-print, not peer-reviewed] A longitudinal study of 101 blood samples from 32 people recovering from COVID-19 found that memory B cells for anti-receptor binding domain (RBD) IgG antibodies increase over time and persist for up to 8 months post-symptom onset. Detectable IgG and sustained Fc-effector activity in plasma was also observed up to 8 months,…
January 25, 2021
SARS-CoV-2 Reinfection in a Cohort of 43,000 Antibody-Positive Individuals Followed for up to 35 Weeks
[Pre-print, not peer-reviewed] A study of SARS-CoV-2 reinfection in Qatar found that reinfection was rare, and that natural infection elicited strong antibody response with at least 90% efficacy lasting at least 7 months. Among study participants (n = 314) with at least one PCR positive swab ≥14 days after the first-positive antibody test, 129 (41.1%)…
Previous page Next page