key predictors of igg seropositivity in individuals exposed to sars-cov-2 prior to vaccine rollout

Introduction: the covid-19 pandemic has highlighted the need to understand factors influencing the immune response to sars-cov-2. immunoglobulin g (igg) antibodies serve as indicators of prior exposure and potential immunity. this study aims to identify demographic, clinical, and exposure-related predictors of igg positivity in individuals exposed to sars-cov-2 before the initiation of vaccination programs.materials and methods: a cross-sectional study was conducted among 944 participants recruited from healthcare facilities. eligible participants were aged 18 years or older, presented with covid-19 symptoms or known exposure to confirmed sars-cov-2 cases, and had not received a covid-19 vaccine. data were collected via structured questionnaires, including demographics, clinical symptoms, and exposure history, and analyzed using logistic regression. igg antibodies were detected using the sars-cov-2 igg elisa method.results: igg antibodies were detected in 75.0% of participants. younger age (b = -0.026, p < 0.001), divorced marital status (b = 0.973, p = 0.021, exp(b) = 2.65), recent international travel (b = 0.953, p = 0.047, exp(b) = 2.594), and symptoms such as runny nose (b = 2.561, p = 0.012, exp(b) = 12.96), nausea (b = 1.614, p = 0.048, exp(b) = 5.025), and lack of appetite (b = 1.366, p = 0.049, exp(b) = 3.918) were significant predictors of igg positivity. each additional year of age was associated with a 2.6% reduction in the likelihood of igg positivity. the model achieved 75.4% classification accuracy with an auc of 0.640, indicating moderate predictive performance.conclusion: this study demonstrates the importance of demographic, clinical, and exposure-related factors in predicting igg positivity. the findings enhance understanding of immune responses to sars-cov-2 and provide insights that can guide public health strategies in mitigating the pandemic's impact.