HealthDay News — For many individuals, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antispike antibodies remain for at least 6 months after infection, according to a report published by the UK Biobank.
To determine the extent of past infection with SARS-CoV-2 in different population subgroups, the UK Biobank collected blood samples from about 20,200 individuals on a monthly basis for 6 months.
A total of 18,893 individuals (93.5%) provided at least 1 sample that was successfully assayed between May 27 and December 4, 2020. The researchers found that 9% of individuals had at least 1 sample that was seropositive for SARS-CoV-2 antispike antibodies during the study period. Seroprevalence differed significantly by age, ethnicity, geographic region, and socioeconomic status. Overall, 1264 individuals were seropositive in month 1. The duration of seropositivity was assessed among those who were seropositive in month 1 and had reported symptoms or had a positive polymerase chain reaction test. Of these 705 participants, 12.2% sero-reverted within 6 months of symptom onset. Only 5 participants (<1%) sero-reverted within 3 months.
“Although we cannot be certain how this relates to immunity, the results suggest that people may be protected against subsequent infection for at least 6 months following natural infection and, potentially, vaccination,” Naomi Allen, DPhil, chief scientist at the UK Biobank, said in a statement. “More prolonged follow-up will allow us to determine how long such protection is likely to last.”