According to the CDC, “the United States is once again seeing a rise in COVID-19 cases, hospitalizations, and deaths.” CDC data shows that as of July 22, 35% of counties across the country are experiencing “high levels” of transmission.

“COVID-19 cases are on the rise in nearly 90% of U.S. jurisdictions, and we are seeing outbreaks in parts of the country that have low vaccination coverage,” the CDC noted.

National Institutes of Health head Dr. Anthony Fauci expressed frustration over the data, telling CNN in an interview that “we’re going in the wrong direction.”

Speaking to Yahoo Finance, Dr. Taison Bell stated he “agreed” with Fauci.

“We are in much worse shape than I certainly thought that we would be at this time, and I think that's really because the delta variant has changed everything,” Bell, assistant professor of medicine at the University of Virginia, said.

Bell described the variant as “one of the most transmissible respiratory viruses that we've ever seen,” and that it might be time to reconsider mask mandates.

“When you're in the midst of a surge, which we definitely are, vaccination certainly has a role. But remember, it does take time to train the immune system to have that response,” he said.

“Public health mitigation measures really are your way to break the back of a surge. We need to take a strong look at mask mandates and bring them back,” he added.

In fact, the CDC is reportedly set to recommend that even vaccinated people wear masks indoors in parts of the U.S. where the coronavirus is surging, a reversal from its earlier guidance. The agency is also expected to recommend all students and teachers at kindergarten through 12th grade schools wear masks regardless of vaccination status, according to reports.

Bell explained, the surge in the delta variant means that “we have to respond to what's happening right now.”

“We have a variant that's more transmissible. But that means that we have to change strategy. And so I think what's more important is that we can react to what's going on right now and make that decision,” he said, on reopening the country.

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“Before the Delta variant, we were doing quite well. Cases were going down, our vaccination was rolling along, and we hadn't hit that plateau yet," he said. "This is a very different day, compared to that day.”

As the variant surges, Bell says he believes there will “likely be a recommendation for boosters,” especially in individuals who didn’t generate a good enough immune response after their first vaccination course.