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. Key QuestionsO_TEXTBOXKey Questions for SARS-CoV-2 O_LIWhat are the kinetics of immune responses to infection? C_LIO_LIDo people who have more severe disease mount stronger antibody responses after infection? C_LIO_LIHow do antibody responses vary between different types of antibodies or as measured by different assays? C_LIO_LIHow does the presence of antibodies impact the clinical course and severity of the disease? C_LIO_LIIs there cross-reactivity with different coronaviruses? C_LIO_LIDoes cross-reactivity lead to cross-protection? C_LIO_LIWill infection protect you from future infection? C_LIO_LIHow long will immunity last? C_LIO_LIWhat are correlates of protection? C_LI C_TEXTBOX