SARS-CoV-2 incidence and effect on absences at a university hospital in Germany

BACKGROUND: The COVID-19 pandemic highlighted the challenges and risks of in-hospital exposures among the health workforce. Health facilities were compelled to conduct their operation while both securing patient care and employees’ health in the context of changing regulatory requirements. METHODS: We performed Time Series Models and a T-Test for Polymerase Chain Reaction (PCR) SARS-CoV-2 in-hospital test results reported via the digital COVID-19 platform of the LMU University Hospital, Germany. The cohort consists of all persons employed at the hospital during the platform's utilisation (N = 14,419; 11.2021-12.2022). RESULTS: Overall, 179,135 in-hospital PCR tests were executed (monthly range: 5,528-24,560; R2=.993) of which 6,538 were positive (monthly range: 92-1,095; R2=.991). In a symptomless or evanescent course of infection, employees were able to get a control test and resume their duties prior to the designated end of isolation if their viral load were below the benchmark of, initially, 100,000 or, as adapted later, 1,000,000 copies/ml (as per Robert Koch Institute's recommendation): 8,100 PCR control results below the respective benchmark were reported (monthly range: 92-1,429; R2=.995). In total, 6,841 persons were able to resume duties prior to their isolation expiration date (monthly range: 10-1,478; R2=.996). No significant differences between the monthly number of PCR tests indicating a new infection and control tests were observed (t=−1.246, p=.235). Incidence trends were tracked closely via the hospital's platform. CONCLUSIONS: The number of executed and positively reported tests fluctuated considerably. The benchmark for PCR tests in positive symptomless or evanescent cases allowed for a large number of staff to resume their duties prior to the expiration of their mandated isolation, yet without presenting a risk to other employees or patients. This measure prevented major staff shortages and ensured the uninterrupted provision of patient care at the hospital. KEY MESSAGES: • The establishment of a control test process facilitates the risk-reduced resumption of duty following a positive PCR test and reduces the isolation period with a decisive effect on staff capacity. • In-hospital test surveillance requires evidence-informed and agile adaptations, thus highlighting the need for centralised strategic management, including segmented visualisation and analysis.