Study population and setting
In this cross-sectional study, health care workers (HCW) at 2 teaching hospitals in the Netherlands (Amphia Hospital in Breda; Elisabeth-TweeSteden Hospital in Tilberg) who reported fever or mild respiratory symptoms in the previous 10 days were tested for SARS-CoV-2 infection via self-collected oropharyngeal swabs between March 7 and March 12, 2020. Structured interviews to document symptoms of those who tested positive were conducted between March 12 and March 16, 2020. As of March 7, 2020 (the date HCW screening began), there had only been 9 documented SARS-CoV-2 cases at the Amphia Hospital and 5 in the Elisabeth-TweeSteden Hospital.
Summary of Main Findings
Among the 9705 HCWs employed at the two hospitals, 1353 (14%) reporting fever and/or respiratory symptoms were tested, 86 (6% of those tested) were infected with SARS-CoV-2 (83% female, median age: 49 years). All HCW with a positive test for SARS-CoV-2 reported at least one of the following symptoms: fever, cough, shortness of breath, severe myalgia, general malaise. Only 3 (3%) reported previous exposure to an inpatient known to be diagnosed with COVID-19, and 21 (24%) did not have patient contact. At the time of data collection, only 2 of the HCWs had been hospitalized, and 19 (22%) had recovered (median duration of illness: 8 days).
Symptom screening was self-reported using structured interviews. There were no missing data.
Only symptomatic HCWs were screened for SARS-CoV-2, which could underestimate the prevalence of infection. Self-collected oropharyngeal swabs were used, which have lower sensitivity (higher false negative rate) than nasopharyngeal swabs. Only a small percentage of the HCWs had recovered by the time of interview, and follow-up of participants was not conducted, so it remains unknown whether any participants went on to develop severe symptoms or critical illness. Participating HCWs self-reported symptoms, which can lead to bias due to over or under-reporting. Given the descriptive nature of the study, no formal hypotheses were tested nor were analyses adjusted for any potential confounders.
The study screened symptomatic health care workers for SARS-CoV-2, and collected data on symptoms via a structured questionnaire during the early stages of the pandemic in the Netherlands.