Antibody (Ab) responses to SARS-CoV-2 can be detected in most infected individuals 10-15 days following the onset of COVID-19 symptoms. However, due to the recent emergence of this virus in the human population it is not yet known how long these Ab responses will be maintained or whether they will provide protection from re-infection. Using sequential serum samples collected up to 94 days post onset of symptoms (POS) from 65 RT-qPCR confirmed SARS-CoV-2-infected individuals, we show seroconversion in >95% of cases and neutralizing antibody (nAb) responses when sampled beyond 8 days POS. We demonstrate that the magnitude of the nAb response is dependent upon the disease severity, but this does not affect the kinetics of the nAb response. We further reveal that the nAb response after SARS-CoV-2 infection is typical of an acute viral infection with declining nAb titres observed following an initial peak. Whilst some individuals with high peak ID 50 (>10,000) maintained nAb titres >1,000 at >60 days POS, some with lower peak ID 50 had nAb titres approaching baseline within the follow up period. A similar decline in nAb titres was also observed in a cohort of seropositive healthcare workers from Guy’s and St Thomas’ Hospitals. This study has important implications when considering widespread serological testing, Ab protection against re-infection with SARS-CoV-2 and the durability of vaccine-induced protection.
Longitudinal evaluation and decline of antibody responses in SARS-CoV-2 infection
[Category] MERS, SARS,
[Article Type] Observational Study
[Source] PMC
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