Statewide mask mandate could drastically slow the spread of COVID-19, scientists say

DENVER (KDVR) – Colorado’s new statewide mask mandate could help the state reverse the trend of increasing COVID-19 cases and hospitalizations, according to public health experts.

Gov. Jared Polis announced the mandate Thursday, after coronavirus cases and hospitalizations had been increasing for about a month in the state.

“It (a mask mandate) works significantly to such degree, that in two weeks to six weeks, you can see a marked difference in the transmission rate of COVID disease in the community,” said Dr. May Chu, a clinical professor of epidemiology at the Colorado School of Public Health.

Chu is now leading a group of nine universities and laboratories to study exactly how effective masks and face coverings are for preventing the spread of COVID-19, for both the person wearing the mask and others. But she said there’s plenty of anecdotal evidence from states and countries to show mask mandates work.

According to the governor’s presentation, counties with mask mandates had a 20 percent decrease in COVID-19 growth from May 20 to June 3, while counties without the mandate saw COVID-19 cases increase 15 percent.

A recent study from the New England Journal of Medicine looked at how aerosols and droplets fly from people’s mouths when they talk. The study’s video shows hundreds of particles being released when a man talked without a mask, but virtually none when he had a mask on. Another analysis shows those particles multiply and fly farther with coughs and sneezes.

“This virus requires a susceptible person to infect to continue the transmission,” Chu said. “If you’re blocking and putting a barrier in front of that transmission…it simply cuts the transmission. Once you reduce the transmission, then the virus dies because there is no place else to go.”