Residents in nine of Arizona's 15 counties, including Maricopa County, should be wearing face masks in indoor public places because of COVID-19 levels, updated federal guidance says.
The Centers for Disease Control and Prevention "community level" guidance for COVID-19 mitigation measures is updated weekly and ranks counties as low, medium and high or green, yellow and orange.
Masks are recommended in public indoor places, including in schools, when a community level is designated as "high."
CDC guidance updated Thursday says the nine Arizona counties designated at the "high" level, where masks are recommended, are Maricopa, Pinal, Apache, Coconino, Gila, La Paz, Mohave, Navajo and Yavapai.
Only about one in five counties in the U.S. was designated at the "high" level in the latest update, the CDC guidelines say, suggesting Arizona is one of the higher risk areas in the country.
Thursday's update also marks the first time Maricopa, Coconino and Yavapai counties have been rated "high" since the CDC began posting the data in late February.
Three counties are designated in the "medium" level — Yuma, Pima and Cochise counties, and three were at the "low" level — Graham, Greenlee and Santa Cruz counties.
Masks are not recommended when communities are in the low level, nor for most at the medium level except for certain people, including those who are immunocompromised, at high risk for severe disease, or if they have a household or social contact with someone at high risk for severe disease. The CDC also recommends "enhanced prevention measures in high-risk congregate settings" in communities designated at the medium level.
The metrics are based on a county’s COVID-19 hospital bed use, COVID-19 hospital admissions and case rates for the virus over the past week.
Arizona has been reporting higher case counts in recent weeks, although case numbers in recent months likely are not showing the full picture of infections as many more people have used at-home test kits and may not report positive results to county health departments.
Percent positivity was at 28% for the week of June 19, the highest it's been since January.
Other areas in the U.S. with large concentrations of counties designated at the "high" community level as of Thursday were California, Florida and Oregon.
Reach the reporter at Alison.Steinbach@arizonarepublic.com or at 602-444-4282. Follow her on Twitter @alisteinbach.
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This article originally appeared on Arizona Republic: Residents of 9 AZ counties should wear face masks indoors, CDC says