Here’s where you should wear a mask indoors under new CDC guidance

The Centers for Disease Control and Prevention (CDC) on Tuesday released updated guidance that recommended many Americans again wear masks when they venture into indoor public spaces such as grocery stores, theaters and arenas.

The update came amid an alarming rise on COVID-19 cases across the country that suggests the highly contagious delta variant is surging and can also be transmitted by people who have been vaccinated.

The guidance itself advised fully vaccinated people in counties with “substantial” and “high” COVID-19 transmission to wear masks in public indoor settings.

But that was criticized as a confusing message by many public health experts on the outside, who said many people won’t know if they are in a “substantial” or “high” transmission area.

Here’s where you should be wearing a mask. 

The South

About 63 percent of the nation is now a high or substantial transmission area, but the South is at the center of the new surge. 

The CDC considers counties to have substantial transmission if they’ve recorded between 50 and 99 total cases per 100,000 people in seven days or if between 8 and 10 percent of their tests returned positive.

Similarly, high transmission counties are places counting 100 or more total cases per capita in a week or seeing 10 percent or more tests come back positive.

The South is painted mostly red for high transmission in the CDC’s county guidance, with the entirety of Louisiana, Arkansas and Florida considered to have high COVID-19 transmission. The new masking recommendations apply in all but two counties in Missouri, Mississippi and Alabama. 

Other Southern states, including Tennessee, Georgia, North Carolina, South Carolina and Kentucky, documented mostly high transmission.

Vaccination rates also tend to be lower in Southern states. According to the database kept by The New York Times, six of the 10 states with the lowest vaccination rates are in the South. 

The South also has almost all of the counties dealing with the highest average daily case count per population. The top 40 counties with the most COVID-19 cases per capita are all located in the South and Missouri, according to data from The New York Times.

The 10 counties with the highest average case total per population are mostly in Louisiana, with two in Texas and one in Mississippi. Dimmit County, Texas, is tracking an average of 255 daily cases, more than twice the amount two weeks prior.

It’s not just the South

The problem is not nearly just the South, despite its heavy red tone in the CDC map.

Red also dominates in Nevada, Utah, Wyoming, Illinois, Kansas and Indiana. 

With mostly orange and red counties, most of Arizona, California, Colorado and Oregon are instructed to follow the new mask guidance as well.  

In total, the new guidance applies to almost 1,500 counties.

All but four states have counties with substantial or high transmission, designated in orange and red, respectively, on the CDCs county-level map.

Only a few states are less high for transmissions

The CDC map, last updated on Sunday, shows Connecticut, Rhode Island, Vermont and Maryland as the sole states having counties with moderate and low spread, designated in yellow and blue, respectively.

Northeastern and some Midwestern states are currently faring the best with mostly moderate transmission rates amid scattered red and orange counties.

But Josh Liao, an associate professor of medicine at the University of Washington School of Medicine, pointed out that historically in the pandemic, hot spots have emerged and changed quickly.

“What may have been, so to speak, a safe area in July, early August may not be that in September and October and vice versa,” he said. 

Not all of the Northeast is free from the CDC recommendations, with masks being recommended for the fully vaccinated in some areas, including all of New York City. All five counties in the Big Apple are seeing at least substantial transmission in the past week, with Staten Island identified as a hot spot. 

Washington, D.C., faces some confusion, as CDC’s county-level map from Sunday labels the District at moderate transmission levels where the mask recommendations don’t apply. But the state-level map updated Tuesday classified D.C. with substantial transmission rates, activating the new guidance.  

Following the CDC announcement, the U.S. House declared it would resume its mask mandate, and the White House Correspondents’ Association said reporters would be required to wear masks 

The CDC’s recommendation for all adults and students in K-12 schools to wear masks regardless of their vaccination status applies across the U.S. 

Delta is the problem

COVID-19 cases have more than doubled in two weeks amid the spread of the highly transmissible delta strain that dominates all of the U.S. and makes up an estimated 82 percent of all cases as of mid-July. 

CDC Director Rochelle Walensky said the decision to bring back mask recommendations for the fully vaccinated was based on emerging data showing that vaccinated people can transmit the delta variant. 

“This new science is worrisome and unfortunately warrants an update to our recommendations,” she said Tuesday.

But the CDC director emphasized that masks are a “temporary measure” to drive down transmission, and vaccines are the more permanent solution. 

The CDC still considers the vaccines to be effective against serious illness, with Walensky saying the risk of symptomatic disease is estimated to be reduced sevenfold and the risk of hospitalization and death decreased twentyfold. 

She considers the surges to “still largely” represent “a pandemic of the unvaccinated,” saying data shows the “vast majority” of severe illness, hospitalization and deaths are occurring among unvaccinated individuals. 

“I strongly encourage everyone to get vaccinated,” she said. “Getting vaccinated continues to prevent severe illness, hospitalizations and deaths even with delta. It also helps reduce the spread of the virus in our community.”