Health care workers have been at the forefront of the COVID-19 pandemic response and are at high risk for acquiring SARS-CoV-2 infection. Infected health care workers can transmit SARS-CoV-2 to coworkers and patients, including persons at risk for severe illness. Therefore, preventing SARS-CoV-2 infection in health care workers is essential to both maintaining an adequate health care workforce and preventing iatrogenic infections.

Along with other infection control measures in the hospital setting, personal protective equipment, including masks, is a key component of strategies to prevent SARS-CoV-2 in health care workers. However, the optimal mask type remains uncertain. N95 and equivalent ...

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