Healthcare workers’ SARS-CoV-2 infection rates during the second wave of the pandemic: prospective follow-up study

Abstract

AbstractObjectivesTo assess if healthcare workers during the second wave of the coronavirus disease 2019 (COVID-19) pandemic had increased severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection rates following close contact with patients, co-workers and persons outside work with COVID-19.MethodsA prospective cohort study of 5985 healthcare workers from Denmark were followed November 2020 to April 2021 and provided day-by-day information on COVID-19 contacts. SARS-CoV-2 infection was defined by the first positive polymerase chain reaction (PCR) test ever.Results159 positive and 35 996 negative PCR tests were recorded during 514 165 person-days. The SARS-CoV-2 infection rate following close contact with COVID-19 patients 3-7 days earlier was 153.7 per 100,000 person-days corresponding with an incidence rate ratio (IRR) of 3.17 (40 cases, 95% CI 2.15 - 4.66) compared with no close contact. IRRs following close contact with co-workers and persons outside work with COVID-19 were 2.54 (10 cases, 95% CI 1.30 - 4.96) and 17.79 (35 cases, 95% CI 12.05 - 26.28). The estimates for close contact with COVID-19 patients, co-workers or persons outside work were mutually adjusted.ConclusionsDespite strong focus on preventive measures during the second wave of the pandemic, healthcare workers were still at increased risk of SARS-CoV-2 infection when in close contact with patients with COVID-19. Among all health care workers, the numbers affected due to close patient contact were comparable to the numbers affected following COVID-19 contact outside work.