ABSTRACT
OBJECTIVE: In this study, we investigated the impact of the SARS-CoV-2 vaccination on seroprevalence in a cohort of healthcare workers (HCW) at an ophthalmic medical center. METHODS: IgG antibodies against the N, S1, and S2 antigens of SARS-CoV-2 as well as their serum neutralizing activity were determined. RESULTS: In the present study, we observed that 98.4% of HCW were seropositive for S1/S2 proteins of SARS-CoV-2 due to the national vaccination program. Interestingly, 78.4% of the participants had anti-N protein antibodies, suggesting previous COVID-19 infection. We also evaluated the neutralizing antibodies and found that the mean value was high (90.7%). CONCLUSION: These results indicate that our HCWs cohort presented a robust hybrid humoral response owing to the massive national vaccination program and natural infections.
ABSTRACT
PURPOSE: During the COVID-19 pandemic, healthcare workers (HCWs) are at a considerable risk of being infected with SARS-CoV-2; among them, HCWs from ophthalmology departments are more prone to develop severe symptoms. In Mexico City, the prevalence of SARS-CoV-2 infection among HCWs is 30%. The present work aims to describe the seroprevalence among HCWs at an Ophthalmological Reference Centre in Mexico City. METHODS: A self-report questionnaire, RT-PCR test and detection of serum IgG/IgM antibodies against SARS-CoV-2 were performed among HCWs at the Institute of Ophthalmology "Conde de Valenciana". RESULTS: A total of 169 HCWs participated in the study. None of the participants declared severe symptoms, and only 15% showed three or more symptoms. The results showed that 32% of the participants were RT-PCR+ (54/169), and 20% (35/169) presented IgG antibodies against SARS-CoV-2. Thirteen percent of the RT-PCR+ subjects were IgG positive, and 7.6% of the RT-PCR- participants were IgG positive. The presence of three or more symptoms correlated with the presence of IgG antibodies, as well as Ct values of < 32 (p < 0,05). CONCLUSION: Most of the HCW cohort showed mild symptoms, and 69% of the RT-PCR+ participants did not show IgG antibodies against SARS-CoV-2. Seroprevalence was significantly associated with the presentation of COVID-19-associated symptoms.