Prevalence of SARS-CoV-2 Infection among Health Care Workers of a Hybrid Tertiary COVID-19 Hospital in Kerala, India

Introduction: Health Care Workers(HCWs) have more risk of exposure, and those working in critical care units are likely to have exposure to higher viral inoculum load from aerosol generating procedures. The risk of acquisition of infection is higher in those who work in hybrid hospitals compared to those designated as Coronavirus Disease-2019 (COVID-19) hospitals. Aim: To estimate the prevalence of Severe Acute Respiratory Syndrome-Coronavirus-2019 (SARS-CoV-2) infection among Health Care Workers (HCWs) of a hybrid COVID-19 treatment hospital in Kerala. Materials and Methods: This cross-sectional study was conducted in the Central Biochemistry Laboratory, Government Medical College, Thiruvananthapuram, Kerala, India, during the period 8th January 2021 to 19th January 2021. Among 3550 HCWs, 979 subjects were selected and grouped into high risk and low risk category, based on their job profile in the hybrid hospital. Results: Finally, 940 HCWs were analysed in the study grouped as high risk (n=859) and low risk (n=81). SARS-CoV-2 Immunoglobulin (Ig) was detected in 180/940 (19.1%) of them. Seroprevalence among the high-risk group was 20.3% (174/859) and that in low-risk group was 7.4% (6/81) (p=0.005). In high-risk group, seropositivity was noted in 30.54 % (76/249) of nurses, 19% hospital attenders (30/158), 18.9% (59/312) resident doctors and 6.4% (9/140) consultant doctors. In those with a positive history of SARS-CoV-2 infection, seropositivity was found among 75.4% (101/134). In those who were COVID-19 positive during July 2020, 33.3% (6/18) were still IgG reactive. Conclusion: The study reported 19.1% SARS-CoV-2 IgG reactivity among HCWs. Seropositivity was significantly higher in high-risk group compared to low-risk. Antibody decay kinetics was comparable to that in published literature. Infection control challenges in hybrid hospitals account for higher seropositivity in this study, compared to overall seroprevalence among HCWs in Kerala.