A systematic review of antibody mediated immunity to coronaviruses: antibody kinetics, correlates of protection, and association of antibody responses with severity of disease

Abstract

The duration and nature of immunity generated in response to SARS-CoV-2 infection is unknown. Many public health responses and modeled scenarios for COVID-19 outbreaks caused by SARS-CoV-2 assume that infection results in an immune response that protects individuals from future infections or illness for some amount of time. The timescale of protection is a critical determinant of the future impact of the pathogen. The presence or absence of protective immunity due to infection or vaccination (when available) will affect future transmission and illness severity. The dynamics of immunity and nature of protection are relevant to discussions surrounding therapeutic use of convalescent sera as well as efforts to identify individuals with protective immunity. Here, we review the scientific literature on antibody immunity to coronaviruses, including SARS-CoV-2 as well as the related SARS-CoV-1, MERS-CoV and human endemic coronaviruses (HCoVs). We reviewed 1281 abstracts and identified 322 manuscripts relevant to 5 areas of focus: 1) antibody kinetics, 2) correlates of protection, 3) immunopathogenesis, 4) antigenic diversity and cross-reactivity, and 5) population seroprevalence. While studies of SARS-CoV-2 are necessary to determine immune responses to it, evidence from other coronaviruses can provide clues and guide future research.

Modeling serological testing to inform relaxation of social distancing for COVID-19 control

“…First, we assume that antibodies are immediately detectable after resolution of infection. In reality, this likely occurs between 11 to 14 days post infection (37), similar to SARS-CoV-1 (38). A small fraction of recent infections would be undetected, but this would have a minor effect on our results.…”

“…Third, we assume that antibodies detected by serology are a correlate of protection. Antibody kinetics of SARS-CoV-1 and MERS suggest that protection will last for at least months and as 20 long as several years (38).…”

“…Baseline contact matrices for 'work' contacts, 'school' contacts, 'home' contacts, and 'other' contacts were taken from (38). To expand these baseline matrices to the 5 population groups in our model (separating the adult population into f c, rc, and h classes), we multiplied all contacts with adults x i,ad by the proportion of the adult population falling into each class.…”

“…f.home = n home n home + n reduced + n f ull f.reduced = n reduced n home + n reduced + n f ull f.f ull = n f ull n home + n reduced + n f ull For baseline contact matrix values based on (38)., we have:…”

Seroprevalence of antibodies against SARS-CoV-2 among health care workers in a large Spanish reference hospital

“…Importantly, the correlation between seropositivity or antibody levels and protection against reinfection, as well as the duration of protective immunity, remains to be elucidated. 11 This study aims to estimate the seroprevalence of antibodies against SARS-CoV-2 and characterize the antibody profile in HCW from Hospital Clínic of Barcelona, one of the reference centers in Spain for the diagnosis and treatment of COVID-19 disease. As a secondary objective, we aim to assess the overall infection prevalence (past and current) to SARS-CoV-2 as well as the prevalence of asymptomatic infections.…”