Seroprevalence of SARS-CoV-2 among ICU Healthcare Workers

 Coronavirus disease-2019 (COVID-19) has affected most countries in the world. The Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) was first reported in late December 2019 in Wuhan, China, and then spread around the world. In Iran, the first case with a definitive test was reported on February 20 in Qom province and a month later in March, the first case was reported in Mashhad. Hospital staff is among the most susceptible groups who are more likely to be infected due to direct contact with patients. The aim of this study was to evaluate the serum prevalence of antibodies against COVID-19 in patients with or without clinical symptoms working in the Intensive Care Unit (ICU) of hospitals affiliated with Mashhad University of Medical Sciences.

 The present study is a cross-sectional study of sero-epidemiological type that was conducted to investigate the serological prevalence of COVID-19 in the period from August 25 to September 30, 2020, in Mashhad. A total of 300 serum samples were collected from the ICU staff of the hospitals affiliated with Mashhad University of Medical Sciences. Sero-prevalence and 95% confidence interval (CI) were calculated for all individuals who were stratified by job title, COVID-19 risk of exposure, direct contact with patients, hospitals, and intensity of care. The significance level was set generally at p < 0.05. Data were analyzed using SPSS V.25.

 The total sero-prevalence of IgG N antibody was 30.67% in COVID-19 ICU healthcare workers. The most prevalence (35.21 %) was recorded in nurse assistances who have the most contact with patients. Among asymptomatic individuals, 17.1% showed to be positive without any symptoms which emphasize the risk of the virus spread from this population who are not aware of their infection. Odds ratios and 95% confidence intervals were reported in the results. The significant difference indicates a statistically significant association with a p-value less than 0.05 (P-value=0.001).

 Our study showed that less contact with patients with COVID-19 results in a lower risk of infection. Also, there is a high percentage of positive people among the staff who did not show any symptoms of the disease.