Gargle pool PCR testing in a hospital during medium and high SARS-CoV-2 incidence.

BACKGROUND: Hospitals need to be protected from SARS-CoV-2 infections to protect vulnerable patients. Thus, a safe, efficient, and cost-effective SARS-CoV-2 testing system for hospitals, in addition to standard hygiene measures and vaccination of staff, is necessary. Here we report on the feasibility and performance of a pool real-time reverse-transcriptase polymerase-chain-reaction (rRT-PCR) test system at, medium and high incidence. METHODS: We implemented a testing concept based on gargling at home and pooling of samples in the hospital before PCR testing in the laboratory. We used two PCR systems (point of care and standard 96-well plate system) to adapt to challenges in the hospital setting and respond to a rising incidence in the Omicron wave. FINDINGS: During our 10-week study period, we performed 697 pool PCRs (8793 tests in total) and identified 65 asymptomatic staff members by pool PCR and 94 symptomatic staff members by positive individual PCR. Virus loads in those detected by pool testing were significantly lower (P<0.001). The test system remained workable even during the peak of the Omicron wave and no outbreaks occurred in any specific area of the hospital during the study period. Unvaccinated individuals were over-represented in the positively tested (37% vs 22% positive tests, P=0.04). The test procedure was well accepted by a majority of the hospital staff (84%). CONCLUSION: Repeated gargle pool rRT-PCR testing can be implemented quickly in hospitals and is an effective, easily adaptable and well-accepted test system for hospitals, even during phases with very high infection rates.

A strict mask policy for hospital staff effectively prevents nosocomial influenza infections and mortality: monocentric data from five consecutive influenza seasons.

BACKGROUND: Influenza infections acquired in hospital show increased mortality, especially in elderly patients with risk factors. Nevertheless, vaccination rates are low among both high-risk patients and healthcare workers (HCWs). AIM: To more effectively prevent influenza infections in the hospital during the influenza season, a strict mouth-nose protection (MNP) requirement was introduced for all staff throughout the shift on the affected wards as an intervention and its effect on nosocomial infection rates was studied. METHODS: The present data were obtained in a retrospective, monocentric analysis over a period of four consecutive influenza seasons from 2015 to 2019. MNP for all staff during the whole shift as an intervention was introduced in 2017 and for the following seasons if at least three influenza patients were in the ward at the same time. Data from hospitalized influenza patients before and after intervention were compared with regard to nosocomial incidences and mortality. FINDINGS: In the years with strict mandatory MNP (2017-2019), the nosocomial influenza incidence fell nearly 50% (odds ratio: 0.40; 95% confidence interval: 0.28-0.56; P < 0.001) accompanied by a significant reduction in nosocomial mortality by 85% (0.15; 0.02-0.70; P = 0.007). The infectious pressure indicated by influenza incidences and patient-days at risk were comparable before and after intervention, as was the low rate of vaccine uptake by nurses. CONCLUSION: Mandatory MNP for HCWs effectively protects patients from nosocomial influenza infections and mortality.