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Citing new evidence that the delta variant of the coronavirus could be spread through rare “breakthrough” infections in vaccinated people, the U.S. Centers for Disease Control and Prevention on Tuesday recommended increased public mask use in regions where the variant is spreading quickly and at schools.

The new guidelines are aimed at everyone, regardless of whether they’ve been vaccinated, signaling a reversal by the CDC for the first time since recommendations were relaxed in May.

In Texas, however, Republican state leaders held their ground against allowing local schools and governments to require masks, sticking with statewide bans on pandemic-era restrictions even as hospitalizations continue to rise and large cities and counties in the state have been strengthening their health recommendations.

Gov. Greg Abbott “has been clear that the time for government mandating of masks is over,” said Renae Eze, Abbott’s press secretary, in an emailed statement to The Texas Tribune. “Now is the time for personal responsibility. Every Texan has the right to choose whether they will wear a mask, or have their children wear masks.”

On Tuesday, a prominent Texas teachers group called on Abbott to let districts impose campus mask mandates with school set to begin in two weeks while national education advocates applauded the new CDC guidelines.

“Educators are eager to return to the classroom, but the pandemic is still dangerous,” said Ovidia Molina, president of the Texas State Teachers Association, in a statement Tuesday.

The CDC now recommends that all students, teachers and visitors wear masks in schools, and that vaccinated people start masking up again in indoor public spaces in “areas with substantial and high transmission,” officials said Tuesday.

Officials did not say how they would define a “high-transmission area” in terms of percentages or numbers. Texas, however, has seen sharp increases in hospitalization rates for COVID-19 patients across much of the state since early July — with the fastest increases being reported in East Texas, in metro areas, and in some of the more rural counties between Austin and Dallas, according to the Texas Department of State Health Services.

The new CDC guidelines are not mandates and don’t carry the weight of law, and Texas is one of a handful of states that won’t allow enforcement of such rules.

Eze said Abbott’s office continues to urge all eligible Texans to get the vaccine, calling it “the most effective defense against contracting COVID and becoming seriously ill,” but added that the vaccine “will always remain voluntary and never forced in Texas.”

The CDC’s updated guidelines do not include a recommendation for vaccine mandates.

About 50% of Texans have gotten at least one dose of a coronavirus vaccine, and 43% are fully vaccinated. That number fluctuates drastically by area, with some metro counties reporting vaccination rates upwards of 60% while other, more rural counties are under 35%.

Cases, positivity rates and hospitalizations are still down compared with earlier surges in the winter and last summer, both in Texas and across the country. Texas has seen nearly 9,000 COVID-related deaths since February, and only 43 of those were unvaccinated people as of last week.

And while daily vaccination rates in Texas have seen an uptick in recent weeks, the pace has fallen off dramatically compared with the high demand seen across the nation in the spring — worrying state health officials who blame the delta variant of the virus for sending hospitalization rates back up for the first time since the winter.

“These aggressive variants, combined with the millions of Texans who have no protection against the pandemic virus, create the very real potential that the surge we are already beginning to see could be another rapid surge with devastating consequences for Texans,” Texas State Health Commissioner Dr. John Hellerstedt said in a video statement Friday.

Hellerstedt pleaded with Texans to get vaccinated.

“We’re so close, Texas,” he said. “Let’s end the pandemic, let’s end the illness, and the loss of life. Let’s show the world that Texans care. Please, Texas. Get fully vaccinated, get your second or first dose today. We are in a race against time, and we can win.”

In May, the CDC recommended that vaccinated people wear masks in mass-transit situations and health care settings with high-risk people nearby, but said overall that those who were inoculated against the virus could resume most of their pre-pandemic lifestyles — large, maskless gatherings and all.

The relaxed guidelines, which came around the same time that Texas lawmakers banned vaccine “passports” by businesses and ended government and school mandates, were based on sharp reductions in deaths and hospitalizations and the effectiveness of the vaccine against the variants.

The vaccine is still extremely effective against the virus, scientists say. But in recent weeks, an “extraordinary amount of viral transmission” — coupled with outbreak investigations that have shown rare instances of transmission through vaccinated people — signals a return to caution by everyone is needed to slow the spread, particularly in areas with rapidly increasing rates, Dr. Rochelle Walensky, director of the CDC, said Tuesday.

“Unlike the alpha variant that we had back in May, where we didn’t believe that if you were vaccinated you could transmit the virus, this is different with delta,” Walensky said. “We are seeing that it is now possible, with the rare breakthrough infection, that you can transmit it further, which is the reason for the change.”

In the U.S., just over 49% of the population is fully vaccinated, according to the CDC.

With so many people still unvaccinated and allowing unfettered spread through their populations by the delta variant, “the big concern” is that a new, more dangerous — and perhaps vaccine-resistant — strain could emerge, Walensky said.

The virus is still spread mostly through unvaccinated people, and the vast majority of those who are hospitalized or die from it are unvaccinated, she said.

“I think we still largely are in a pandemic of the unvaccinated,” she said Tuesday. “We continue to strongly encourage everyone to get vaccinated. … The highest spread of cases and severe outcomes is happening in places with low vaccination rates and among unvaccinated people.”

Reese Oxner contributed to this report.

Disclosure: The Texas State Teachers Association has been a financial supporter of The Texas Tribune, a nonprofit, nonpartisan news organization that is funded in part by donations from members, foundations and corporate sponsors. Financial supporters play no role in the Tribune's journalism. Find a complete list of them here.

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This article originally appeared in The Texas Tribune at https://www.texastribune.org/2021/07/27/texas-masks-cdc-covid-19/.

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