Health officials expect Delta variant will become dominant COVID-19 strain in US

COVID-19 vaccine
Posted at 7:12 AM, Jun 15, 2021

TAMPA, Fla. — Researchers are watching the COVID-19 Delta variant closely.

“Almost 10% of the sequence samples we’re seeing are the Delta variant in the U.S.,” said Dr. Michael Teng, Virologist and Associate Professor for University of South Florida Health.

Experts say that number is climbing fast. They believe the Delta variant is behind the outbreak in India that has killed at least 374,305 people so far, according to the Johns Hopkins COVID-19 tracker.

“We find one, it makes people sicker. Two, it’s more transmissible. Three, having COVID before does not often protect you. This is a very dangerous variant,” said Dr. John Sinnott, Chairman of the Department of Internal Medicine at the University of South Florida and Epidemiologist at Tampa General Hospital.

With more people back out in the community and gathering again, healthcare officials say they’re not surprised we’re now dealing with another mutation, especially since there are still so many unvaccinated people.

“Frankly as long as there are unvaccinated people in the world the virus is going to circulate and as the virus circulates and transmits from person to person, it’s going to try to find a way to make itself transmit better. That’s just what viruses do, it’s the natural evolution of a virus,” said Teng.

With the Delta variant scientists are now seeing the same pattern they saw with the U.K. variant, also known as the Alpha variant when it became the dominant strain in the United States.

"The U.K. shows this increase in the Alpha variant that came to the United States with a six-week lag. I think we’re kind of in the same time frame,” said Teng.

Experts believe the Delta variant is around 40% to 60% more contagious than the Alpha variant and expect it to take over cases in the U.S.

“Like some of the other ones that we’ve seen, it has a little bit of immune evasion,” said Teng.

The good news is research shows people who are fully vaccinated are still protected from the Delta strain.

According to the Centers for Disease Control and Prevention, 43.7% of people are fully vaccinated.

“With even just one dose of the Pfizer vaccine, it was only 33% effective against the delta strain. With two doses it was up to 88%,” said Dr. Mark Pamer, Pulmonologist.

Experts say places with low vaccination rates are at risk for outbreaks with this variant.

“Because we’re not able to vaccinate the entire population in the world, I expect there’s going to be a variant after Delta that has even increased transmissibility beyond that of Delta,” said Teng.

Health officials in the state say we’ve done pretty well vaccinating older people, but now they need younger populations to step it up.