Health workers in US coronavirus units NINE TIMES more at risk

For the first study, researchers compared asymptomatic healthcare workers in coronavirus units to those not working with coronavirus patients. About 5.4% of employees in COVID-19 units had positive test results as did 0.6 percent from non-COVID wings. In a second study, a team looked at the amount of microdroplets expelled by someone who breathes and coughs to assess coronavirus risk. Hospital ventilation systems have about 10 air exchanges per hour, which means the concentration plateaus after around 30 minutes. By comparison, a typical office only has about three air exchanges per hour, so the concentration increases for more than one hour