Prevalence of SARS-CoV-2 among Belgian workers in long-term care facilities

Background Healthcare workers (HCWs) can be a source of SARS-CoV-2 within long-term care facilities (LTCFs); therefore, we analysed the data from a testing programme among LTCF employees. Aims The aim of this study was to investigate the prevalence of SARS-CoV-2 and its determinants among employees of LTCFs and the risk for fellow workers and residents. Methods Testing started at week 15, the first wave's peak, using nasopharyngeal swabs for PCR up to week 23. At the start of the second wave (week 32), testing resumed. Results A total of 32 457 test results were available from 446 LTCFs: 2% were positive: 1% in men, 2% in women, 2% in HCWs (=having patient contact), 1% in non-HCWs, higher in younger age groups. In total, 30 729 employees were tested once, 823 twice, 66 thrice and 4 four times. Prevalence was 13% during the first week of testing (week 15) and declined to 7% (week 16) to stay at around 1% (from week 17 until week 23). At the start of the second wave (week 31-33), the prevalence was around 3%. In 70% of positive tests, the employee was asymptomatic. Conclusions Our study confirms the presence of HCWs with SARS-CoV-2 as a possible source of infection in LTCFs even when the incidence in the general population was low; 70% were asymptomatic. To control the spread of SARS-CoV-2 in LTCFs vaccination, infection prevention and control measures are necessary as well as testing of all LTCF HCWs during possible outbreaks, even if asymptomatic.