COVID-19’s fourth wave is hitting the US hard

A fourth wave of coronavirus infections is beginning to mount in states across the nation as health experts and officials beg pandemic-exhausted Americans to stay vigilant.

The United States has reported an average of 65,000 new cases in the last seven days, according to data from the Centers for Disease Control and Prevention (CDC), up about 10,000 cases per day since the most recent nadir two weeks ago.

Those figures are well below the January apex of the third wave of infections, when a quarter-million people a day were testing positive for the virus. 

But while millions of Americans are receiving vaccinations, progress toward herd immunity has not kept pace with the new spike. Cases are rising in about half the states, led by big spikes in New York and especially New York City, Michigan, New Jersey, Connecticut and Pennsylvania. 

“Our work is far from over. The war against COVID-19 is far from won. This is deadly serious,” President Biden said Monday at the White House, hours after CDC Director Rochelle Walensky pleaded for the public to keep up mitigation strategies. “If we let our guard down now, we could see a virus getting worse, not better.”

Scientists say the new spike is being driven by the emergence of variants of the coronavirus, most notably a more readily transmissible and virulent strain known as B.1.1.7, first identified in the United Kingdom. CDC data shows that strain is responsible for an estimated 13 percent of new cases in Florida and 9 percent of cases in New Jersey.

But the number of cases is also being spurred by behavior changes as weary Americans increasingly participate in nonessential activities. States have loosened restrictions, in some cases altogether, and several states have dropped or are planning to scrap mask mandates.

“There is more indoor crowding. If I walk out in the street in Boston I see indoor crowding in restaurants and shopping,” said Abraar Karan, an internal medicine specialist at Brigham and Women’s Hospital and the Harvard Medical School. “We knew that when you start to reopen there will be more social and physical interactions.”

After a year of errors and missteps in handling the pandemic, the vaccination campaign stands out as a distinct bright spot. 

The number of Americans who have received a vaccine against the coronavirus is growing by more than 2 million a day, according to CDC data. The United States is vaccinating a larger share of its population than any nation other than Israel, the United Arab Emirates, Chile and the United Kingdom.

More than 17 million doses have been administered in California, and more than 11 million have been given in Texas. More than a third of residents of smaller states like New Mexico, Connecticut, South Dakota, Alaska and Maine have received at least one dose.

Vaccine administration rates are highest among the elderly, who received top priority as early rounds of vaccines were rolled out over the last several months. But millions more must be vaccinated before the United States reaches some form of herd immunity.

“It’ll be at least another six to eight weeks before we get that kind of coverage,” said Celine Gounder, an infectious diseases specialist at New York University’s Grossman School of Medicine and a member of the Biden administration’s COVID-19 advisory board. “We’re almost there, it’s just not the time to give up.”

The high number of older Americans who have been vaccinated coupled with improved clinical care practices are reducing the number of deaths caused by COVID-19. Fewer than 1,000 people a day have died of the virus over the last week for the first time since November. The number of Americans being treated in hospitals is around 40,000, less than a third of the number of patients in January.

“I’m hopeful that even if we do have another surge, we’ll deal with it better this time. But the surge was avoidable,” Karan said. “Now that the train has been set in motion, infections that are happening today you’ll see in the next couple of weeks.”

Even with the progress, health care workers and experts have been left exhausted by the pandemic that has killed more than 550,000 Americans. Amy Arlund, an intensive care unit nurse at Kaiser Fresno Medical Center, said her hospital went through a period in which every person admitted to the ICU died.

“I just had to stop counting the body count. After 100 people dying in my ICU, the numbers just became overwhelming,” Arlund said. “It’s hit me that I’m not so sure I want to do this anymore.”