A year after omicron began its assault on humanity, the ever-evolving coronavirus mutant has driven up the number of COVID-19 cases in many places, just as Americans came together for Thanksgiving. It was the prelude to a wave that experts expect to sweep the United States soon.
Phoenix-area emergency physician Dr. Nicholas Vasquez said his hospital has admitted increasing numbers of chronically ill people and nursing home residents with severe COVID-19 this month.
“It’s been a while since we needed COVID units,” he said. “He’s making a comeback.”
Nationally, new COVID cases averaged about 39,300 a day on Tuesday — far lower than last winter, but a vast undercount due to reduced testing and reporting. About 28,000 people with COVID have been hospitalized daily and about 340 have died.
Cases and deaths increased from two weeks earlier. Yet one-fifth of the US population has not been vaccinated, most Americans have not received the latest boosters, and many have stopped wearing masks.
Meanwhile, the virus continues to find ways to avoid defeat.
The omicron variant arrived in the United States just after Thanksgiving last year and caused the biggest wave of cases of the pandemic. Since then, it has spawned a large extended family of subvariants, such as those currently most common in the United States: BQ.1, BQ.1.1, and BA.5. They edged out their competitors by better evading immunity to vaccines and previous diseases – and sickening millions of people.
Carey Johnson’s family has been hit twice. She caught COVID-19 in January during the first wave of omicron, suffering flu-like symptoms and terrible pain that kept her going for a week. Her son Fabian Swain, 16, suffered from much milder symptoms in September when the BA.5 variant was dominant.
Fabian recovered quickly, but Johnson had a headache for weeks. Other problems lasted longer.
“I was like, ‘I can’t do this together.’ I couldn’t gather my thoughts. I couldn’t gather my energy,” said Johnson, 42, of Germantown, Maryland. “And it went on for months like that.”
Hot spots appear
Some communities are particularly affected at this time. Mayo Clinic tracking shows cases are trending up in states including Florida, Arizona, Colorado and New Mexico.
In Arizona’s Navajo County, the average daily case rate is more than double the state average. Dr James McAuley said 25 to 50 people a day test positive for coronavirus at the Indian Health Service facility where he works. Before, they only saw a few cases a day.
McAuley, clinical director of Whiteriver Indian Hospital, which serves the White Mountain Apache Tribe, said they were “essentially back to where we were with our last big spike” in February.
COVID-19 is part of a triple threat that also includes influenza and the virus known as RSV.
Dr. Vincent Hsu, who oversees infection control for AdventHealth, said the system’s pediatric hospital in Orlando is nearly full of children sick with these viruses. Dr. Greg Martin, past president of the Society of Critical Care Medicine, sees a similar trend elsewhere.
Emergency departments and urgent care clinics at pediatric hospitals are busier than ever, said Martin, who practices primarily at Grady Memorial Hospital in Atlanta. “That’s a record from any month, any week, any day in the past,” he said.
Looking ahead, experts see the seeds of a widespread American wave. They point to what’s happening internationally – a BA.5 surge in Japan, a combination of variants driving up cases in South Korea, the start of a new surge in Norway.
Some experts have said an American surge could start over the holidays as people gather indoors. Trevor Bedford, a biologist and genetics expert at the Fred Hutchinson Cancer Research Center, said it could peak at around 150,000 new cases a day, about what the nation saw in July.
A new wave would be rough, said Dr. Mark Griffiths, medical director of the emergency department of Children’s Health Care at Atlanta-Spalding Hospital. “So many systems are on the verge of being totally overloaded that if we get another COVID surge on top of that, it’s going to crack some systems.”
A bright spot? Deaths will likely be much lower than at the start of the pandemic. About 1 in 2,000 infections lead to death now, up from about 1 in 200 in the first half of 2020, Bedford said.
The One Year Reign of Omicron
The same widespread immunity that reduced deaths also caused the coronavirus to mutate. By the end of last year, many people had been infected, vaccinated or both. This “created the initial niche for the spread of omicron,” Bedford said, as the virus had evolved significantly in its ability to evade existing immunity.
Omicron flourished. Mara Aspinall, who teaches biomedical diagnostics at Arizona State University, noted that the first strain of omicron accounted for 7.5% of circulating variants in mid-December and 80% just two weeks later. Cases in the United States at one point soared to one million a day. Omicron generally caused less severe illness than previous variants, but hospitalizations and deaths increased given the number of people infected.
The giant wave receded in mid-April. The virus rapidly mutated into a series of subvariants capable of evading immunity. A recent study in the journal Science Immunology indicates that this ability to evade antibodies is due to more than 30 changes in the spike protein studding the surface of the virus.
Omicron has evolved so much in a year, Bedford said, that it’s now “a meaningless term.”
This rapid change is likely to continue.
“There’s a lot more pressure for the virus to diversify,” said Shishi Luo, infectious disease manager for Helix, a company that provides viral sequencing information to the US Centers for Disease Control and Prevention.
Doctors said that the best protection against bubbling stew of subvariants remains vaccination. And officials said Americans who got the new combination booster targeting omicron and the original coronavirus are currently better protected than others against symptomatic infections.
Dr. Peter Hotez, co-director of the Center for Vaccine Development at Texas Children’s Hospital, said receiving the booster, if you’re eligible, is “the most impactful thing you can do.”
Doctors are also urging people to continue testing, maintain preventative measures such as masking in crowds and stay home when sick.
“COVID is still a very significant threat, especially to the most vulnerable,” said Dr. Laolu Fayanju of Oak Street Health in Cleveland, who specializes in care for the elderly. “People have to keep thinking about each other. We’re not completely off the hook on that yet.