COVID-19 seroprevalence among healthcare workers of a large COVID Hospital in Rome reveals strengths and limits of two different serological tests

Abstract

In several hospitals worldwide, healthcare workers are currently at the forefront against coronavirus disease 2019 (COVID-19). Since Fondazione Policlinico Universitario A. Gemelli (FPG) IRCCS has been enlisted as a COVID hospital, healthcare workers deployed to COVID wards were separated from those with limited or no exposure, whereas administrative staff was destined to work-from-home. Between June 4 and July 3 2020, an investigation was carried out to evaluate seroprevalence of SARS-CoV-2 IgG antibodies among employees of the FPG using point-of-care (POC) and venous blood tests. Sensitivity, specificity and predictive values were determined with reverse-transcription polymerase chain reaction (RT-PCR) on nasal/oropharyngeal swabs as gold standard.Four thousand, seven hundred seventy-seven participants were enrolled. Seroprevalence was 3.66% using the POC test and 1.19% using venous blood test, with a significant difference between the two (p < 0.05).POC sensitivity and specificity were, respectively, 63.64% (95% confidence interval (CI): 62.20% to 65.04%) and 96.64% (95% CI: 96.05% to 97.13%), while those of the venous blood test were, respectively, 78.79% (95% CI: 77.58% to 79.94%) and 99.36% (95% CI: 99.07% to 99.55%). Among low-risk population, point-of-care’s predictive values were 58.33% (positive) and 98.23% (negative) whereas venous blood test’s were 92.86% (positive) and 98.53% (negative). In conclusion, point-of-care tests have low diagnostic accuracy, while venous blood tests seem to show an overall poor reliability.

Seroprevalence of Covid-19 infection among healthcare workers: A study from a tertiary care hospital in the National Capital Region of India

“…[1][2][3] Studies in HCWs showed variable seroprevalence of 14.5% (Scotland), 7 1.2% (Japan) 8 and 3.66% in Rome. 9 Indian data from Srinagar and Kolkata show prevalence in HCWs ranging from 0.6% to 11.94% 4,5 in September 2020. The seroprevalence in our study was 46.2%, which is much higher compared to the Srinagar and Kolkata studies.…”

Is Covid-19 seroprevalence different in health care workers as per their risk of exposure? A study from a tertiary care hospital in National Capital Region of India

“…The prevalence and distribution of antibodies to SARS-CoV-2 in a healthy adult populations of various countries such as the Netherlands (2.7%) [23], Turkey (2.7%) [24], Spain (11.2%) [25], a public hospital in New York (27%) [26]. Studies in health care workers showed an equivalently wide spread 14.5% in the Scottish study [27], 1.2% (Japan) [28] 3.66% in Rome [29]. Indian data from two metropolitan studies (Srinagar and Kolkata) show a variation in the prevalence in health care workers ranging from 0.6% to 11.94% [10][11].…”