Decline in #SARS-CoV-2 Antibodies After Mild Infection Among Frontline Health Care Personnel in a Multistate Hospital Network — 12 States, April–August 2020 | MMWR
▻https://www.cdc.gov/mmwr/volumes/69/wr/mm6947a2.htm
Deuxième dosage des anticorps 60 jours après la mise en evidence d’une séropositivité (▻https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7470460) chez des sujets qui avaient développé une forme légère de la maladie.
Summary
What is already known about this topic?
Most persons develop virus-specific antibodies to SARS-CoV-2 after infection; however, the timeline of antibody decline over time is uncertain.
What is added by this report?
Among 156 frontline health care personnel who had positive SARS-CoV-2 antibody test results in spring 2020, 94% experienced a decline at repeat testing approximately 60 days later, and 28% seroreverted to below the threshold of positivity. Participants with higher initial antibody responses were more likely to have antibodies detected at the follow-up test than were those who had a lower initial antibody response.
What are the implications for public health practice?
SARS-CoV-2 antibodies decline over weeks following acute infection. Negative SARS-CoV-2 serologic results do not exclude previous infection , which has significant impacts on how serologic studies are interpreted.
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... misclassification of antibody status was possible; however, this was considered to be unlikely because of the high sensitivity and specificity of the ELISA.
These antibody declines might not equate to loss of protective immunity or increased risk for #reinfection; this was not assessed in this study.
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Whether decay in these antibodies increases risk for reinfection and disease remains unanswered.