For nearly two months, fully vaccinated people in the U.S. have been able to go back to living life much like they had been before the pandemic. With vaccination rates climbing, the Centers for Disease Control and Prevention (CDC) announced in mid-May that fully vaccinated individuals no longer needed masks indoors or outdoors, leading state officials to lift not only mask mandates, but to return to business as usual by removing social distancing or capacity restrictions, too. It seemed we were on the path towards normal this summer, but a new variant of the coronavirus is starting to sound alarms again. The Delta variant has already forced other countries like India and Australia, back into lockdown and reinstated restrictions. And now, it's quickly spreading in the U.S., and in certain states in particular.
CDC Director Rochelle Walensky, MD, told Good Morning America on June 18 that she expected the Delta variant to become dominant in the U.S. in the coming months. "It's more transmissible than the Alpha variant, or the U.K. variant, that we have here," she said. "We saw that quickly become the dominant strain in a period of one or two months, and I anticipate that is going to be what happens with the Delta strain here." But less than two weeks later, things are already starting to take a turn. As of June 30, CNN confirmed that the Delta variant had been located in all 50 states, and it's now the dominant COVID strain in four of them.
Trevor Bedford, PhD, an affiliate associate professor at the department of genome sciences at the University of Washington, confirmed on Twitter on July 1 that the Delta variant is now the dominant strain of COVID in Missouri, Utah, Colorado, and Arkansas. It's overcome the formerly dominant Alpha variant in these states in less than four weeks, Bedford said.
According to the data Bedford provided, Missouri has had the biggest spread of the Delta variant. In May, 80 percent of cases in the state were caused by the Alpha variant, but now, that variant is only behind about 10 percent of new cases. The Delta variant, on the other hand, was responsible for 30 percent of cases in May, but now is causing more than 80 percent of new cases in the state.
This is exactly what experts have been expressing concern about in recent weeks. Just over a week ago, White House COVID adviser Anthony Fauci, MD, said that the prevalence of the Delta variant was quickly doubling in the U.S. At that point, it accounted for more than 20 percent of all cases in the country.
"Look at the growing threat of what we're all concerned about: the Delta variant," Fauci said during a June 22 White House briefing. "The transmissibility is unquestionably greater than the wild-type SARS-CoV-2, as well as the Alpha variant. It is associated with an increased disease severity, as reflected by hospitalization risk, compared to Alpha."
Experts are especially worried about unvaccinated individuals as the Delta variant spreads. All but one of the states now dominated by the Delta variant have some of the lowest vaccination rates in the country. According to data from Johns Hopkins University, Missouri has fully vaccinated 36.6 percent of its population, Utah has fully vaccinated 34.9 percent, and Arkansas has 31.7 percent fully vaccinated. Colorado is the only outlier with 49.5 percent of its population fully vaccinated.
"In certain countries, the Delta variant has become really quite dominant. It has pushed aside the other variants that are there. This will happen in our country, the United States, in those areas of unvaccinated people," Fauci said during a June 29 interview with PBS. "Again, that's the reason why we say we're dealing with something we have to take very seriously. It's really a dichotomy. If you're vaccinated, you're in reasonably good shape, in fact, quite good shape. If you're not vaccinated, you're at significant risk."