Zients said the Biden administration expects cases to increase in the weeks ahead because of spread in communities with low vaccination rates. Four states accounted for 40% of new cases last week, with one in five coming from Florida.
The COVID-19 curve in the U.S. is rising again after months of decline, with the number of new cases per day doubling over the past three weeks, driven by the fast-spreading delta variant, lagging vaccination rates and Fourth of July gatherings.
Confirmed infections climbed to an average of about 23,600 a day on Monday, up from 11,300 on June 23, according to Johns Hopkins University data. And all but two states — Maine and South Dakota — reported that case numbers have gone up over the past two weeks.
At the same time, parts of the country are running up against deep vaccine resistance, while the highly contagious mutant version of the coronavirus that was first detected in India is accounting for an ever-larger share of infections.
Nationally, 55.6% of all Americans have received at least one COVID-19 shot, according to the CDC. The five states with the biggest two-week jump in cases per capita all had lower vaccination rates: Missouri, 45.9%; Arkansas, 43%; Nevada, 50.9%; Louisiana, 39.2%; and Utah, 49.5%.
Even with the latest surge, cases in the U.S. are nowhere near their peak of a quarter-million per day in January. And deaths are running at under 260 per day on average after topping out at more than 3,400 over the winter — a testament to how effectively the vaccine can prevent serious illness and death in those who happen to become infected.
Zients said there are signs that increased cases are driving more people in those communities to seek vaccination at rates faster than the national average.
The delta variant is a version of the coronavirus that has been found in more than 80 countries since it was first detected in India. It got its name from the World Health Organization, which names notable variants after letters of the Greek alphabet.
Viruses constantly mutate, and most changes aren’t concerning. But there is a worry that some variants might evolve enough to be more contagious, cause more severe illness or evade the protection that vaccines provide.
Experts say the delta variant spreads more easily because of mutations that make it better at latching onto cells in our bodies. In the United Kingdom, the variant is now responsible for 90% of all new infections. In the U.S., it represents 20% of infections, and health officials say it could become the country’s dominant type as well.
It’s not clear yet whether the variant makes people sicker since more data needs to be collected, said Dr. Jacob John, who studies viruses at the Christian Medical College at Vellore in southern India.
Studies have shown that the available vaccines work against variants, including the delta variant.
Dr. James Lawler, a leader of the Global Center for Health Security at the University of Nebraska Medical Center in Omaha, said bringing back masks and limiting gatherings would help. But he acknowledged that most of the places seeing higher rates of the virus “are exactly the areas of the country that don’t want to do any of these things.”
Lawler warned that what is happening in Britain is a preview of what is to come in the U.S.
“The descriptions from regions of the world where the delta variant has taken hold and become the predominant virus are pictures of ICUs full of 30-year-olds. That’s what the critical care doctors describe and that’s what’s coming to the U.S.,” he said.
He added: “I think people have no clue what’s about to hit us.”
The Associated Press contributed to this report.