Fourth wave of virus hits US

Unvaccinated kids, adults may suffer most from spread

A doubling of COVID- 19 cases in the past two weeks suggests the USA has entered a fourth wave of the pandemic.

The example of the United Kingdom suggests the infection rate could get high, while hospitalizations and deaths stay relatively low.

Instead of the virus raging through entire communities, it is likely to target the unvaccinated, including children, and if rates are high enough, the most vulnerable of the vaccinated – the elderly and the immunocompromised.

“Since the majority of our population is now immune, it’s unlikely that we’re going to return to the massive nationwide waves we saw back in January,” David Dowdy, an infectious disease epidemiologist with the Hopkins Bloomberg School of Public Health, said.

But major outbreaks can still occur, particularly in areas with low vaccination rates.

“We’re going to be living in two pandemic worlds, the world that’s vaccinated and the world that’s unvaccinated,” said Luis Ostrosky, chief of infectious diseases at UTHealth and an infectious disease specialist at Memorial Hermann- Texas Medical Center in Houston.

The three vaccines authorized for use in the USA, from Moderna, PfizerBioNTech and Johnson & Johnson, have all been shown to be highly effective against variants of the virus, including delta, which accounts for most of the cases in the nation.

More than 99% of those hospitalized with COVID- 19 are unvaccinated. Ostrosky said virtually all his patients are unvaccinated and all regret not getting the shots.

COVID- 19 may not be as deadly in this new wave, because older people are largely vaccinated and younger people are less likely to die from an infection, said Ravina Kullar, an infectious disease specialist and epidemiologist and adjunct faculty member at UCLA Medical Center. But the delta variant is substantially more contagious.

“The concern about delta is wellplaced,” said Dr. Yonatan Grad, an infectious disease specialist at the Harvard T. H. Chan School of Public Health. “We’re certainly seeing that this wave is something to contend with and not to take lightly.”

COVID- 19 rates are rising again

In the U. K., which has roughly the same rate of vaccinations as the USA, the seven- day average number of infections is back to where it was Jan. 20.

In the USA, infections have more than doubled since the week of June 22. New cases are rising in all 50 states, and hospitalizations are increasing, according to data out Sunday from Johns Hopkins University. More than 25,000 U. S. patients who probably had COVID- 19 were in hospitals Saturday, up 24.1% from a week earlier. Throughout the week, hospitals admitted 51,378 likely COVID- 19 patients, up 15%, and 6,198 adults with COVID- 19 were in intensive- care units, up 25.7%.

Still, the infection rates are well below what they were at the January peak.

There’s still another spike expected this fall. The coronavirus is probably seasonal, which means people are more vulnerable in colder months.

About 80% of those over 65 are fully vaccinated in the USA, so younger people represent a higher percentage of those falling ill. Although children under 12 are unlikely to get a severe case, they are unable to get vaccinated, so they remain vulnerable to the delta variant.

“By virtue of kids not having the opportunity to be vaccinated at the same level as adults, I think they are going to experience a disproportionate burden of infection and sickness from the delta variant,” Dowdy said.

The vaccines are good but not perfect. People who get infected after vaccination, even if their infection is so mild they don’t notice, could be contagious, though probably less than those who aren’t vaccinated, Grad said.

Those who get mild disease after vaccination could suffer symptoms of “long- haul COVID,” said Priya Duggal, an epidemiologist at Johns Hopkins.

People who have caught COVID- 19 are likely to be protected against reinfection for at least a year, according to a study published in the journal Nature. Researchers found that getting vaccinated after infection boosted by 50- fold the activity of neutralizing antibodies needed to repel the virus and prevented infection with variants.

“There are still unknowns about the extent and duration of protection from natural infection and how well there’s protection against new variants,” Grad said. “Even people who have had COVID- 19 are still advised to get vaccinated.”

Although the vaccines appear effective against variants, if the virus spirals out of control anywhere in the world, new variants could challenge immunity, Dowdy said. “As long as the virus is circulating, mutating in other countries, it’s going to be a threat to us, too,” he said.

What can be done?

To reverse the increase in infections, what’s needed “is really injecting a sense of urgency into the equation,” Ostrosky said, recommending that people get vaccinated and resume wearing masks indoors when in public.

“If we don’t act now, we’re just going to be in the same situation we were in a year ago with closures, with disruptions, with deaths,” he said.

Ostrosky said he thinks there are two types of people declining vaccination: those greatly misinformed and those who need more reassurance that they are not going to be harmed by the shots, which have been given to more than 185 million. “Access is really not the issue right now, it’s more reluctance,” he said.

Unfortunately, he said, the people most reluctant to get vaccinated are also those most reluctant to wear masks.

Kullar said she wishes the Centers for Disease Control and Prevention had waited longer before saying masks are unnecessary for the fully vaccinated. Instead of providing an incentive to get vaccinated, the move encouraged everyone, including the unvaccinated, to take off their masks, she said. “It confused the public even more.”

She said people should wear masks indoors in public places until at least 70% of their community is vaccinated, “and if you’re immunosuppressed, I wouldn’t remove your mask.” Outdoors remains safe, she said, particularly if people keep their distance from others.

The most important thing in the battle against COVID- 19, Ostrosky said, is for people to get vaccinated.

“We can do this,” he said. “We have no time to waste.”