Was there really a need for masks in hospitals during the Corona era?

Research conducted by hospitals affiliated with the Massachusetts General Brigham Medical Center has reported a significant increase in the rate of viral respiratory infections in hospitals after the public use of masks and testing policies for Covid-19 were lifted. This research has shown that with the return of the policy of using masks for health workers during the increase of viral infections in winter, the number of these infections has decreased.

According to the medical news service of Tekna News Media, the public use of masks and testing of patients in hospitals was stopped in May 2023. But in January 2024, due to the increase in viral infections in the winter season, the use of masks for health workers was re-imposed.

This observational study titled Infectious Disease Testing Policies and Mask Use and Nosocomial Viral Respiratory Infections, the effects of mask use and testing policies on the rates of nosocomial viral respiratory infections caused by SARS-CoV-2, influenza, and respiratory syncytial virus (RSV) in The hospitals of a health system in Massachusetts have been investigated.

Researchers analyzed data from 641,483 inpatients from two tertiary care hospitals, seven general hospitals and one specialist eye and ear hospital from November 2020 to March 2024.

Using a mixed Poisson time series design, the researchers modeled hospital-acquired infections, defined as positive PCR tests more than four days after admission, against community-onset infections, defined as positive tests within the first four days of hospitalization.

The periods were divided into four phases: pre-Okron with testing and general mask, Okron with testing and general mask, Okron without testing and general mask, and Okron with the return of masks for health workers.

Adjustments for seasonality and other confounding variables were made using national test data and bootstrap-based confidence intervals. Also, misdiagnosis of nosocomial infections in 100 randomized cases was evaluated based on clinical symptoms, known contacts, and PCR cycle thresholds.

The study recorded 30,071 community-onset respiratory infections and 2,075 hospital-acquired infections. In the pre-Ocron era with general precautions, the average weekly ratio of hospital-acquired infections to community-onset infections was 2.9%. That ratio rose to 7.6 percent during Okron’s tenure with precautions, to 15.5 percent after the precautions ended, and to 8.0 percent after the return of masks for healthcare workers.

After the public use of masks and testing stopped, hospital-acquired infections increased by 25 percent compared to the pre-precautionary period. The return of mask use among healthcare workers was associated with a 33% reduction in hospital-acquired infections.

The findings indicate a measurable relationship between mask use and testing policies and the incidence of nosocomial infections. This study shows that mask use effectively reduces viral infections, especially during periods of increased viral activity in the community.