U.S. states with more people using face masks show lower COVID-19 rates

BOSTON, Mass. — There’s a direct correlation between greater adherence to face masks and lower COVID-19 rates among U.S. states, according to researchers from the Boston University School of Public Health.

We’ve all been hearing about face masks for so long now that they almost feel normal now. Regardless, throughout the pandemic different states have instituted their own versions of COVID-containment laws. Some states have put stricter policies in place than others. Study authors set out to determine just how much of a link there is between mask wearing and subsequent COVID rates. Some clear insight into this matter can help shape public health policies moving forward.

Researchers analyzed any publicly available data regarding mask-wearing, as well as people’s self-reported habits on using masks in public. Finally, the team took into account COVID-19 rates among all 50 U.S. states and Washington, D.C. Based on data spanning May-October 2020, they say the effect of mask wearing is usually visible in COVID rates about a month later. Scientists consider an infection rate of 200 cases per 100,000 residents to be on the high side.

Masks are still the first line of defense against COVID’s spread

Among 15 U.S. states that did not mandate residents wear masks in public, 14 showed a high infection rate. Conversely, among the eight states that reported a mask compliance rate of at least 75 percent, not a single one displayed a high rate of COVID infection. Generally, states with lower rates of mask use had the most risk of a high COVID infection number the following month.

More specifically, the eight states with a 75 percent rate of mask wearing had a mean COVID-19 rate of 109.26 per 100,000 residents the next month. Meanwhile, the mean COVID-19 rate was 239.99 for states with a compliance rate below 75 percent.

All in all, these results support the use of masks to help end the pandemic as quickly as possible.

The study appears in the journal PLOS ONE.