{Reference Type}: Systematic Review
{Title}: COVID-19 antibody responses in individuals with natural immunity and with vaccination-induced immunity: a systematic review and meta-analysis.
{Author}: Zhang Q;Jiao L;Chen Q;Bulstra CA;Geldsetzer P;de Oliveira T;Yang J;Wang C;Bärnighausen T;Chen S;
{Journal}: Syst Rev
{Volume}: 13
{Issue}: 1
{Year}: 2024 Jul 19
{Factor}: 3.136
{DOI}: 10.1186/s13643-024-02597-y
{Abstract}: <B>BACKGROUND: </B>The COVID-19 pandemic has caused a large mortality and morbidity burden globally. For individuals, a strong immune response is the most effective means to block SARS-CoV-2 infection. To inform clinical case management of COVID-19, development of improved vaccines, and public health policy, a better understanding of antibody response dynamics and duration following SARS-CoV-2 infection and after vaccination is imperatively needed.<BR><B>METHODS: </B>We systematically analyzed antibody response rates in naturally infected COVID-19 patients and vaccinated individuals. Specifically, we searched all published and pre-published literature between 1 December 2019 and 31 July 2023 using MeSH terms and "all field" terms comprising "COVID-19" or "SARS-CoV-2," and "antibody response" or "immunity response" or "humoral immune." We included experimental and observational studies that provided antibody positivity rates following natural COVID-19 infection or vaccination. A total of 44 studies reporting antibody positivity rate changes over time were included.<BR><B>RESULTS: </B>The meta-analysis showed that within the first week after COVID-19 symptom onset/diagnosis or vaccination, antibody response rates in vaccinated individuals were lower than those in infected patients (p < 0.01), but no significant difference was observed from the second week to the sixth month. IgG, IgA, and IgM positivity rates increased during the first 3 weeks; thereafter, IgG positivity rates were maintained at a relatively high level, while the IgM seroconversion rate dropped.<BR><B>CONCLUSIONS: </B>Antibody production following vaccination might not occur as quickly or strongly as after natural infection, and the IgM antibody response was less persistent than the IgG response.