Anti-spike Antibody Response to Natural SARS-CoV-2 Infection

Abstract Objective To assess the immune response to natural SARS-CoV-2 infection, anti-spike antibody levels were investigated in a group of 1,348 unvaccinated individuals in Slovakia during the Alpha variant dominance. Methods Blood samples were used to assess SARS-CoV-2 spike-specific mix of antibodies by electrochemiluminescence. Data on demographics, chronic conditions and COVID-19 severity were collected. Statistical analyses were performed to assess the impact of these factors on antibody responses. Results 77.6% of the study group developed detectable anti-spike antibodies. Age, sex, BMI, presence of chronic conditions, and COVID-19 severity were associated with antibody levels. Older individuals, those with overweight or obesity, and those with more severe COVID-19 infections exhibited higher antibody titers. Conclusion These findings highlight the importance of understanding the factors influencing the immune response to SARS-CoV-2. However, the emergence of new viral variants with immune-evasive properties limits the long-term protection conferred by natural infection. Further research is needed to assess the durability of immunity and the impact of vaccination on long-term protection.