Delta variant is now the dominant coronavirus strain in the US, CDC data shows

Carlos Dennis, Ron DeSantis, Javier Crespo
Posted at 2:06 PM, Jul 07, 2021

The delta variant has emerged as the dominant strain of the novel coronavirus in the United States, according to updated data from the Centers for Disease Control and Prevention (CDC).

The CDC’s “variant proportions” website shows the delta variant, otherwise known as B.1.617.2, accounted for an estimated 51.7% of all COVID-19 infections in the U.S. as of July 3.

The next most common strain of the virus is the alpha variant, or B.1.1.7, which is estimated to have accounted for 28.7% of infections in the U.S. as of July 3.

The delta variant also accounts for more than 50% of infections in five of the 10 regions that the Department of Health a Human Services divides the U.S. into, according to the CDC.

Infectious disease experts, like Dr. Anthony Fauci, have warned for weeks that the delta variant is highly contagious and it threatens the nation’s recovery from the pandemic.

“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,” Fauci said during a White House COVID-19 Response Team briefing two weeks ago.

The good news is that vaccines are effective against the delta variant.

“The effectiveness of the vaccines – in this case, two weeks after the second dose of Pfizer-BioNTech – was 88% effective against the delta and 93% effective against the alpha when you're dealing with symptomatic disease,” said Fauci. “When you look at hospitalizations, again, both the Pfizer-BioNTech and the Oxford-AstraZeneca are between 92 and 96% effective against hospitalizations.”

The White House says it’s intensifying its efforts to help states prevent, detect and respond to hotspots among the unvaccinated by mobilizing COVID-19 surge response teams to be at the ready to deploy federal resources and personnel where needed.

“These are dedicated teams working with communities at higher risk for or already experiencing outbreaks due to the spread of the Delta variant and their low vaccination rate,” said Jeffrey Zients, White House coronavirus response coordinator, last week.

By the end of the week, the Biden administration estimates that about 160 million people will be fully vaccinated in the U.S. However, the president is still stressing the importance of every eligible American getting vaccinated, especially as the delta variant continues to spread among unvaccinated people.