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Delta and Beyond: What Variants Mean for the Fully Vaccinated

You're unlikely to get sick if you got the COVID-19 vaccine, but burdens still linger

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A few months ago, life seemed to be inching back to normal for the fully vaccinated. Grandparents were reuniting with grandkids, travelers were booking vacations and more people were leaving their masks at home. But the rise of a new coronavirus variant, known as delta, has crushed the optimism many felt in the early days of summer and replaced it with an air of uncertainty.

Cases of COVID-19, fueled by delta, are higher this summer than they were last summer, and hospitalizations and deaths caused by the highly contagious variant are also on the rise. Unvaccinated individuals are bearing the brunt of delta's wrath, but worries still abound for the vaccinated: Will the variant lead to more restrictions and upend another year of plans? How can we keep young kids who aren't eligible for vaccination safe and shield people with suppressed immune systems? And what about breakthrough infections?

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Delta isn't the first concerning coronavirus variant to pop up — and it won't be the last, experts say. Here's what that means for vaccinated people:

Vaccines work better when more people get them

If you've had your shots, rest assured you have a high degree of protection from getting severely ill or dying from COVID-19. In fact, less than 1 percent of fully vaccinated Americans have been hospitalized with the disease or have succumbed to it, data from the Centers for Disease Control and Prevention (CDC) show. And while reports of asymptomatic and mild breakthrough infections are making headlines, research shows even those are pretty rare.

The vaccines even mount a strong defense against delta, which is more contagious than the other coronavirus strains and perhaps more lethal. A study published in The New England Journal of Medicine found that a full dose regimen of the mRNA vaccines (Pfizer and Moderna) is 88 percent effective against a symptomatic illness caused by a delta infection. And if a vaccinated person is hospitalized with a delta infection, they're less likely to need supplemental oxygen, a preprint study out of Singapore shows.

But vaccines don't just work on an individual level; they “work on a population level,” says James Lawler, an infectious disease expert at the University of Nebraska Medical Center's Global Center for Health Security. “One of the important things about vaccination is it provides this dampening effect across a community that's more than just its effect on one person. It can be synergistic when you have a large portion of the population vaccinated,” he says, explaining that as vaccination rates go up, virus transmission goes down and hospitalizations and deaths will follow.

Increasing population-wide immunity also reduces the risk that a variant even more dangerous than delta will pop up. That's because the more chances a virus has to replicate, or spread from person to person, the more likely it is to mutate.

"That's just essentially spinning the roulette wheel for the virus again, until it potentially has the opportunity to come up with a lucky number,” Lawler says.

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It's unclear how many people need to be vaccinated to avoid this outcome — estimates range between 70 and 90 percent of the population. Currently, about 50 percent of the entire U.S. population is fully vaccinated.

Variants could bring back some restrictions

It's unlikely the U.S. will see a new wave of lockdowns like we experienced in 2020, Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, has said — even as the delta variant rips though communities across the country. But some familiar restrictions could return if cases continue to surge.

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Several cities, counties and businesses are once again requiring masks indoors, following new research that suggests vaccinated people who are exposed to the delta variant can become infected and unknowingly pass the virus on to others, including unvaccinated children and people who are immunocompromised. Even in the absence of mandates, health officials are recommending that people who are fully vaccinated mask up in areas where community transmission is deemed high or substantial. (You can check your area's status on the CDC's website.)

And with delta surging, you may want to consider a mask upgrade, says Luis Schang, a virologist and professor of chemical virology at Cornell University. He recommends a surgical mask, which he says is both effective at blocking virus transmission and more comfortable than the gold-standard N95. “They strike a good balance in between the ease of use and protection,” Schang says.

Wearing a surgical mask under a cloth mask can help improve the protection offered, the CDC says. Knotting the ear loops of your surgical mask also ensures a snugger fit.

It's possible other mitigation efforts, such as physical distancing requirements and crowd limits, could creep back into daily life in areas hit hard by the summer spike. The same goes for travel restrictions, especially overseas. And if they do, Schang encourages patience and tolerance.

"It's up to us to win [the fight against COVID-19]. And we definitely have the tools,” Schang says. “Let's try to be proactive to use the least disruptive measures like getting vaccinated and wearing face masks in order to try to avoid more disruptive measures.”

Breakthrough Infections

No vaccine is 100 percent effective, so breakthrough infections are expected. Here's what you need to know:

  • Not every breakthrough infection results in symptoms. Some cases are asymptomatic.
  • If you do experience symptoms, the vaccine may make your illness less severe.
  • State data collected by the Kaiser Family Foundation found that the rate of breakthrough infections is below 1 percent. More than 166 million people are fully vaccinated, so this translates to fewer than 1.6 million breakthrough cases.
  • Close to 0 percent (0.004) of breakthrough infections have led to hospitalization or death, CDC data show.
  • People with breakthrough infections caused by the delta variant can transmit the virus to others, new research suggests.
  • Breakthrough cases are more likely to occur in areas where there's high transmission.

Fall could get ‘very ugly’

Reports of overwhelmed hospitals are starting to make headlines again in areas where vaccination rates are low and prevention efforts are lax. And all of it is happening right as the country heads into cold and flu season, which by itself can stress the health care system.

Last year's flu season was essentially nonexistent, and experts say all of the efforts put in place to slow the spread of COVID-19 (face masks, distancing, school and office closures, reduced travel, etc.) are the reason why we saw so few influenza cases. But many of those efforts have been scaled back, and routine illnesses are starting to pick up.

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Cases of RSV (respiratory syncytial virus), a common respiratory virus that can be especially dangerous for babies and older adults, are on the rise, CDC data show. Others are “roaring back to normal or even above normal” as well, Lawler says. And when you add COVID-19 to the mix, making sure the health system doesn't get clobbered is “going to be a bigger challenge this fall than it was last year,” Lawler predicts.

Add to it the fact that schools are returning for in-person learning this year. Health officials are recommending that everyone in schools, regardless of vaccination status, wear a mask to help prevent the spread of COVID-19 and to protect younger children who aren't yet eligible for the vaccines. However, not all schools are requiring them.

"So it's going to be, unfortunately, a very ugly fall across much of the country,” says Lawler, who adds that communities with higher vaccination rates will likely “do much better” than those where rates remain low.

"We're probably going to see a combined epidemic wave of COVID, plus influenza, plus parainfluenza, plus RSV — all of the other fall and winter respiratory viruses that we usually see, but actually had very low rates of last year,” he adds.

Variants could outsmart vaccines

While much of the focus remains on delta, researchers are keeping a close eye on other circulating variants, including lambda, which originated in Peru and is responsible for about 1,000 cases in the U.S.

So far, experts are “not yet really worried” about lambda being more contagious than delta, which is about twice as contagious as the other variants, Francis Collins, director of the National Institutes of Health, told ABC's George Stephanopoulos on Aug. 8, “but [it] needs to be looked at.”

Scientists and health officials are also studying how the emerging variants stack up against the current crop of vaccines. “So far, so good,” Collins said. “We don't have anxieties yet about delta or lambda or any of the others that are sort of lurking out there. But we all worry about the day when a variant arises that is so different from the original Wuhan virus, that basically the vaccines stop working as well.”

The best way to avoid that scenario? “Get as many people vaccinated as quickly as we possibly can” before the virus has a chance to mutate into a more menacing version, Fauci said in a recent news briefing.

"It's no question that the vaccines are our answer to get out of this mess if we can get enough people to take them,” Lawler says.

Rachel Nania writes about health care and health policy for AARP. Previously she was a reporter and editor for WTOP Radio in Washington, D.C. A recipient of a Gracie Award and a regional Edward R. Murrow Award, she also participated in a dementia fellowship with the National Press Foundation.

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