Seroprevalence of the General Lebanese Population to COVID-19 Between 2023 and 2024

Background Understanding population immunity to SARS-CoV-2 is crucial for public health planning, especially Lebanon where unique healthcare challenges exist. This study aimed to assess the seroprevalence of SARS-CoV-2 antibodies and identify predictors of serostatus in a sample of the Lebanese population in 2023. Methods We conducted an observational study of 350 adult patients presenting to two emergency departments in Lebanon. Participants were tested using a ZEKMED COVID-19 IgG/IgM rapid test, a qualitative rapid SARS-CoV-2 anti-E antibody kit. A comprehensive statistical analysis including logistic regression, Bayesian modeling, and a Random Forest classifier was performed to identify predictors of IgG seropositivity. Results Our results showed high IgG seroprevalence of 95.1% (n=333), suggesting prevalent natural infection. While vaccination status and self-reported prior infection were not significant predictors of serostatus in standard analyses, both Bayesian and Random Forest models identified increased age as a potential predictor associated with a negative IgG antibody response (94% HDI: [-1.531, -0.000]; importance score: 0.61). Conclusion Our findings indicate high exposure to natural SARS-CoV-2 infection in this Lebanese cohort. However, the association of advanced age with a negative antibody response suggests that older populations may remain more vulnerable. This highlights the need for continued targeted public health surveillance and strategies despite high overall seroprevalence from past infections.