One-year seropositivity after COVID-19 infection: A study from a developing country

Understanding the duration of the humoral immune response after coronavirus disease 2019 infection is critical for assessing vaccination strategies. This study aimed to evaluate the persistence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in patients from Northern Jordan 1 year after infection. A descriptive cross-sectional study was conducted at King Abdullah University Hospital in Irbid, Jordan, from January to March 2021. Participants who were infected with the early SARS-CoV-2 variants circulating in Jordan (B.1, B.1.1, and B.1.1.312) prior to the emergence of the Alpha variant and unvaccinated were tested for antibodies against recombinant spike (S) and nucleocapsid (N) proteins using the quantitative Elecsys Anti-SARS-CoV-2 S and the qualitative Elecsys Anti-SARS-CoV-2 assays, respectively (Roche Diagnostics GmbH, Mannheim). Data were analyzed using Statistical Package for Social Sciences, and chi-square tests were applied to identify associations. Among 122 participants (62 males, 60 females), more than 50% of the patients retained detectable antibodies 1 year postinfection. Spike protein antibodies showed a more consistent long-term presence compared to nucleocapsid antibodies. Blood group O individuals showed the lowest seropositivity rates (P = .06). Other variables, including age, gender, comorbidities, smoking status, and symptom severity, did not show a significant correlation with antibody persistence. SARS-CoV-2 antibodies persist in more than 50% of patients for at least 1 year postinfection, particularly against the spike protein. These findings support the potential for long-term immune protection and may inform vaccination policies, particularly in resource-limited settings.