Sumary of SARS-CoV-2 antibodies wane, depending on age, symptoms and ethnicity:
- Researchers at the University of Oxford have conducted a study of UK healthcare workers showing how antibody responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can wane over time, depending on age, previous symptoms and ethnicity..
- The team longitudinal seroprevalence study of more than 3,200 healthcare workers found that immunoglobulin G (IgG) antibodies against the SARS-CoV-2 nucleocapsid protein waned within months, falling more quickly among young people and asymptomatic individuals..
- The team also observed higher antibody titers and moderate evidence of longer antibody half-lives among Asian healthcare workers, compared with White healthcare workers..
- “Ongoing longitudinal studies are required to determine the long-term kinetics of antibody-mediated response to SARS-CoV-2, and responses to re-exposure.”.
- Previous estimates of antibody duration vary Related Stories Antibodies against SARS-CoV-2, which are generally detectable within 1 to 3 weeks, can be assayed to help estimate the proportion of a population that has been exposed to or infected with the virus..
- “Most epidemiological outbreak models assume that SARS-CoV-2 infection leads to the development of post-infection immunity for a defined duration,”.
- However, measurable IgG antibodies against SARS-CoV-2 antigens do not always develop following infection, and previous estimates of the duration of antibody responses vary..
- Now, Lumley and the team have presented findings from a longitudinal seroprevalence study of 3,217 UK healthcare workers who underwent quantitative serial measurements of IgG antibodies against SARS-CoV-2 nucleocapsid protein..
- Polymerase chain reaction (PCR) testing and antibody testing were offered to both symptomatic workers (from March 27th onwards) and asymptomatic workers (from April 23rd onwards) by the Oxford University Hospitals NHS Foundation Trust across all four of its teaching hospitals in Oxfordshire, UK..
- A Bayesian statistical model was used to investigate the trajectory of SARS-CoV-2 IgG antibody levels and any association with age, ethnicity, previous symptoms and gender..
- Among this cohort of working-age healthcare workers (up to 69 years), antibody levels peaked 24 days following the first positive PCR test, before then beginning to fall..
- “By following quantitative antibody responses, we could separately analyze changes in initial antibody levels and rates of waning,”.
- Among 452 IgG-seropositive healthcare workers tested over a median of 121 days, the estimated mean antibody half-life was 85 days and the estimated mean time until loss of seropositivity was 137 days…