World on brink of fourth wave of coronavirus

A year after the frightening beginning of the coronavirus pandemic, the world stands on the brink of a fourth wave of infection as nations race to vaccinate their populations and stave off a new surge in hospitalizations and deaths.

Total reported cases rose across the globe in the last week of February after six weeks of decline, driven in part by new, more virulent variants that transmit between people at startlingly higher rates than the initial strains out of Wuhan, China, and northern Italy.

“This is disappointing, but not surprising,” World Health Organization Director-General Tedros Adhanom Ghebreyesus told reporters last week. “This is a global crisis that requires a consistent and coordinated global response.”

The United States recorded about 66,000 new cases a day over the last week, according to the Centers for Disease Control and Prevention (CDC), down 73 percent from the apex reached in early January and similar to levels of transmission from October. But the precipitous decline of late January and early February has plateaued in recent days, raising fears that a new wave is just around the corner.

“We could not have made a more wonderful environment for this virus to take off than we have right now,” said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota. “We are not driving this tiger, we’re riding it. And the first time we may be able to drive it is with widespread use of the vaccine, and we’re not there yet.”

A total of 107 million doses of the three vaccines approved by the Food and Drug Administration have been shipped to states across the nation, according to CDC data. About 53 million people have received at least one dose, 16 percent of the population, while 27 million have received two doses. The first doses of the one-shot vaccine developed by Johnson & Johnson were administered last week.

Globally, 115 million coronavirus cases have been confirmed, a quarter — 28.7 million — in the United States. The 518,000 Americans who have died represents about 20 percent of the global death toll. The latest data from the CDC shows 41,000 are still hospitalized.

CDC forecasts show the number of weekly deaths dropping through the rest of March and into April, though the number of deaths will continue at a horrible cost of thousands of lives.

Some models show an increase in cases just around the corner. One model maintained by the PolicyLab at the Children’s Hospital of Philadelphia shows reproduction rates — the measure of how many people are infected by someone who has the virus — rising in three quarters of the counties surveyed. States in the Northeast, Mid-Atlantic and Midwest showed higher transmission rates last week.

Several states have loosened restrictions on businesses and gatherings imposed over the summer, even though infections continue at higher levels today than when those mandates were initially put in place.

“You’re seeing a lot of states loosening mask restrictions at a point where they’re having more cases per day than they had over the summer when they put the mask restrictions in place,” said Rich Besser, a former CDC director who now runs the Robert Wood Johnson Foundation. “That just doesn’t make sense.”

The governors of Texas and Mississippi have removed mask mandates, and most states have lifted capacity rules for indoor establishments like bars and restaurants. Public health experts cautioned against racing to reopen at a faster pace than the science suggests is safe.

“If we’re a little bit too capricious in this in between phase, we can really lengthen this [pandemic] out,” said David Rubin, who runs PolicyLab. “A lot of people very close to the finish line before they’re offered vaccinations can be infected.”

Rubin said the coming spring months are likely to aid the battle against the coronavirus as more people spend more time outdoors. Early warm weather in Southern states may be partly responsible for lower transmission in February, he said.

But the barriers to a return to normal remain in the form of vaccine hesitancy, as millions voice skepticism over shots that have shown no serious medical consequences. 

“If we continue to see this large group of people who are not getting vaccinated, that’s going to have a big impact on sustainability of transmission in the US, even with the vaccine here. We’ve done little to dent that,” Osterholm said. 

Variants that now account for an increasing share of cases in the United States are a growing cause of concern. Scientists are especially concerned about the B.1.1.7 variant, responsible for a winter outbreak in the United Kingdom, and the B.1.357 variant, first identified in South Africa and now prevalent in several of its neighbors.

As more Americans receive their vaccines, communities are looking ahead to a promising spring and summer. But while the light is on at the end of the tunnel, experts warned there is still plenty of tunnel to traverse.

“This in-between time, our collective response with communities and how we go about the next couple months is such a critical moment,” Rubin said. “Everything we do now has an impact on what might happen three months from now.”