CDC study: Mask mandates reduce COVID-19 hospitalizations
States and counties that implemented mask mandates saw a substantial decline in the number of people admitted to the hospital to treat COVID-19 symptoms in the weeks after the mandates took effect, according to a new study published Friday.
The study, published in the Centers for Disease Control and Prevention’s (CDC) Morbidity and Mortality Weekly Report, found hospitalization growth rates begin to drop slightly in the first three weeks after implementation. More than three weeks after a mask mandate took effect, hospitalization rates declined by almost 5 percent.
The study “demonstrates that statewide mask mandates were associated with a reduction in Covid-19-associated hospitalization growth rates,” the researchers wrote.
The study monitored hospitalization rates in 10 states — California, Colorado, Connecticut, Maryland, Michigan, Minnesota, New Mexico, New York, Ohio and Oregon — that implemented mask mandates between mid-April and mid-July.
Thirty-one states and the District of Columbia have implemented mask mandates.
Hospitalization rates dropped most significantly among those between the ages of 18 and 64. Hospitalization rates declined the least among those over 65, who are most susceptible to the worst outcomes of the coronavirus that causes COVID-19.
Drops in hospitalization rates are likely an indicator of fewer infections in the population as a whole. Only a small percentage of coronavirus infections lead to symptoms severe enough to require hospitalization.
“At the individual level, the prevention benefit of using a mask increases as more persons use masks consistently and correctly,” the study says.
The CDC researchers speculated that the decline may have been lowest among older people in part because those over the age of 65 are the most likely to have been wearing masks already, so a mandate would have had the least impact on them.
Studies conducted as early as May — before many states implemented mask mandates — found about 70 percent of those over the age of 65 were already using face coverings, compared to fewer than half of those under the age of 25.
A separate report published Friday showed the number of young people using face masks has increased dramatically. The report found that more than 90 percent of people at six universities across the country, observed between September and November, were wearing face masks correctly.