Updated: Aug. 4, 11:50 a.m. | Posted: July 17, 9:55 a.m.
With the highly contagious delta variant surging ferociously, Americans are once again grappling with pandemic anxiety.
The surge has prompted a flurry of new mask mandates, vaccine mandates and other steps to try to get the coronavirus back under control.
While delta can sometimes infect vaccinated people, infections, hospitalizations and deaths are rising fastest in parts of the U.S. with the most unvaccinated people. Hot spots, however, are burning everywhere from Massachusetts to California.
"While we desperately want to be done with this pandemic, COVID-19 is clearly not done with us, and so our battle must last a little longer," the director of the Centers for Disease Control and Prevention, Dr. Rochelle Walensky, said at a recent White House COVID-19 briefing.
But if you're already vaccinated, how worried should you be? What new precautions are called for? Here's what to know about the fast-spreading variant and how to stay safe and protect others.
How much more contagious is the delta variant, really?
Very. As NPR has reported, the delta variant appears to be around twice as transmissible as the original SARS-CoV-2 strains.
One recent preprint study from China found that people infected with delta have, on average, about 1,000 times more copies of the virus in their respiratory tracts than those infected with the original strain and are infectious earlier in the course of their illness.
No matter how you look at it, delta seems to spread faster, explains Dr. Helen Chu, associate professor of medicine at the University of Washington.
"You can look at it through modeling, you can look at it through population-level data and you can look at it simply by putting the virus into the cell and looking at how quickly it infects the next cell," she says. "In all of those measures, it has looked like it's more transmissible."
If I'm vaccinated, can I get sick with delta?
Yes, but don't panic. While the COVID-19 vaccines are somewhat less protective against delta, they are still highly effective at preventing people from getting severely ill and dying.
During a recent White House briefing, Dr. Anthony Fauci noted that data from the United Kingdom shows the vaccines are 88 percent effective at preventing people from developing symptoms.
Vaccinated people are eight times less likely to get sick and 25 times less likely to end up in the hospital compared with unvaccinated people, Fauci said.
For context, the CDC has documented 6,587 cases of fully vaccinated people who were hospitalized or died from COVID-19 among the more than 163 million people who have been fully vaccinated in the United States.
That works out to far less than 0.01 percent.
"The bottom line of what we are saying is that: Get vaccinated," Fauci said. "The COVID vaccines give strong protection against the delta variant, and it protects you, your family and your community."
Though the CDC only tracks breakthrough infections that lead to hospitalization or death, some states are keeping track of every case. According to an analysis by the Kaiser Family Foundation, among states that track the data, the rate of breakthrough cases among fully vaccinated people ranged from 0.01 percent in Connecticut to 0.29 percent in Alaska.
What about long COVID-19?
While the risk of getting sick if you're vaccinated is very low, if you do get a symptomatic case, it's likely still possible to end up with long-haul COVID-19 symptoms, according to virologist Angela Rasmussen, who works with the Vaccine and Infectious Disease Organization at the University of Saskatchewan in Canada. She notes the data is still quite limited though.
"Even if you don't end up in the hospital, there's certainly a possibility that you could end up with long COVID," she says. "So the safest thing to do is to avoid being infected altogether."
In fact, a recent study from Israel suggested that even people who experience "mild" breakthrough infections may be at risk for symptoms that linger.
The study found that about 1 in 5 people who got infected even though they were vaccinated — 19 percent — experienced symptoms found in long COVID-19 patients that lasted at least six weeks, including headaches, body aches, fatigue and loss of taste and smell. The study, however, was very small, with only seven patients out of about 1,500 study participants experiencing lingering health problems.
Should I go back to wearing a mask in public?
Yes, and many experts advise that you up your mask game to wear the best-fitting mask you can.
In late July, the CDC issued new guidelines stating that even fully vaccinated people should start masking again indoors if they live in an area where the virus is circulating widely. (Check this map with data from the CDC to see if you need to mask up where you live.)
The CDC's new recommendation was based on an investigation of an outbreak that occurred in Provincetown, Mass., around the July Fourth holiday. Researchers discovered that fully vaccinated people who caught the virus could carry as much virus as unvaccinated people, which means they could spread the virus to other people. The findings are consistent with those of other outbreak investigations, the CDC's Walensky said.
The CDC also updated its guidance to recommend that everyone wear masks in schools, regardless of whether they are vaccinated.
"I understand this is all frustrating news, and I share this frustration," Walensky said. "We continue to learn each day from emerging science and use this evidence to update our recommendations."
Before the CDC changed its guidance, many health experts were already calling for vaccinated people to resume masking indoors. Many said they'd never stopped masking.
Bill Miller, a physician and epidemiologist at Ohio State University, says he wears a mask in public places even though he's fully vaccinated. "I know that I am extremely unlikely to get seriously ill. But I also know that if I am exposed, I may become infected and pass it on to others," he says.
Do I need a booster shot?
At this point, no. So far the federal government doesn't recommend booster shots to enhance immunity, though it is actively studying the question.
"The CDC and the FDA are working very hard to get as much data as they possibly can to adequately address that question," Fauci told NPR's Here & Now recently. Federal health officials and vaccine-makers continue to follow participants enrolled in the initial clinical trials for the vaccines to see how well immunity holds up with current vaccinations.
So far, experts say it's encouraging. "The level of antibodies seem to be holding up pretty well, so we have to watch and see what happens over the course of the coming months," Dr. Francis Collins, director of the National Institutes of Health, told NPR in an interview.
Eventually, as immunity wanes, a booster could be recommended for certain groups, including elderly people. There's also research underway to test a mix-and-match approach to booster shots. Researchers are giving study participants who were originally vaccinated with any of the three authorized vaccines a booster shot of the Moderna vaccine.
White House COVID-19 response coordinator Jeff Zients said that the administration is ready for the possibility of boosters "if and when the science shows they are needed."
However, some other countries have either already started or announced plans to soon start giving very vulnerable or older people boosters.
What about kids? Can kids get infected and spread delta?
Yes. Although children tend to have milder cases of the coronavirus, they are certainly susceptible to infection. Children remain the least protected age group, since none of the vaccines is authorized for children under age 12.
It's possible that children who get infected with the delta variant might have more symptoms than they would if they were infected with an earlier version of the virus. With a more transmissible variant, "when someone gets sick, they tend to have more virus, and they tend to have more symptoms," Chu explains.
That being said, Chu says, typically "children are not that symptomatic from COVID." Her best guess? She thinks delta "probably will not lead to significant numbers of children getting hospitalized."
But there's still a reason to keep your kids masked up in public, and that's the risk that they could spread the virus to more vulnerable people, says Rasmussen. "Even if it doesn't impact them, it could impact other vulnerable people in their household, such as people who may not have had a robust response to the vaccine, people who are immunocompromised."
Is it safe to fly, especially with my unvaccinated kids? Any other travel precautions to be aware of?
Infectious disease experts say to use extra caution when traveling. "We are now dealing with a different virus, and we are living in this highly contagious virus' playground," Ravina Kullar, an infectious diseases specialist and epidemiologist at the University of California, Los Angeles, told NPR via email.
Airplanes themselves are generally deemed low risk, given that the air filtration is typically excellent and passengers wear masks. But getting to the airport and waiting around in it could be risky, especially for unvaccinated kids. With that in mind, Kullar says she would hold off on flying with young kids "until delta plateaus" and plan a road trip instead.
Other experts said short flights may be OK. But if you do fly, make sure you and your kids wear well-fitted masks, ideally N95s or KN95s, or double-mask. And keep masks on the entire time you're in the airport and plane.
Whether you plan to fly or drive, take a look at the level of coronavirus spread in the area you're traveling to, advises Helen Boucher, an infectious disease physician at Tufts Medical Center. She advises canceling plans to travel to places with high or "substantial" spread according to the CDC. (Check NPR's map here.)
Dr. Jeanne Marrazzo, an infectious disease specialist at the University of Alabama at Birmingham's School of Medicine, agrees strongly: "One should be very wary of taking a child too young to be vaccinated from a low-incidence state to a high-incidence state like Florida," she told NPR. "Glad I don't have to make those hard choices for my family."
If you fly, there's "no need to quarantine after flying unless a person has symptoms," Dr. Tina Tan, an infectious disease specialist at Northwestern University's Feinberg School of Medicine, told NPR via email. But do avoid busy, crowded vacation spots, she warns. Other agree: Beach parties, bars and crowded concerts, even outdoors ones, could pose a risk during the delta surge.
Should I turn down invitations to weddings and other large gatherings?
Many public health experts say it's safe to attend if you're vaccinated, but keep the variant in mind, especially if you're somewhere with rising cases.
Ohio State's Miller says he encourages mask-wearing for an indoor wedding or event "because you're bringing people together from different social networks, creating a great opportunity for an outbreak."
One case study serves as a reminder that the risk is not zero: Six vaccinated people got COVID-19 after attending a wedding near Houston that was held in a large outdoor tent. All the infected people got symptoms, one was hospitalized and another person — who had received India's Covaxin vaccine — died, according to a preprint case study.
As scary as that sounds, "there could be rare events like these where people are in an enclosed tent and very close to each other. But the vast majority — the vast, vast majority — of viral transmission is happening indoors," says Chu.
Does delta cause different COVID-19 symptoms?
Maybe. Some doctors and public health departments have reported that people infected with delta have different symptoms from the original classic signs of COVID-19: cough, fever and loss of taste or smell. Now, some of the more common symptoms appear to be runny nose, sore throat and headache, according to the ZOE COVID Symptom Study, an ongoing app-based research project based in the United Kingdom.
But Chu warns that it's hard to know what's behind that apparent change, "because the population that it's infecting is not the same population that was infected in the prior waves," says Chu. The people getting sick now tend to be much younger, she says.
Since COVID-19 might present differently in younger people, any changes in symptoms could have less to do with the new variant and more to do with the people who are contracting it. "I don't know that you can disentangle that," Chu says.
"This is already a disease that produces a pretty broad range of different clinical presentations in people," adds Rasmussen. She'd like to see better data before concluding the symptoms are, in fact, different.
Do I need those bleach wipes again?
No extra surface cleaning is necessary. Even though it's more transmissible, delta still transmits the same way the original SARS-CoV-2 virus does. "This type of virus, which is an RNA virus that is enveloped, tends to transmit [through] respiratory transmission," Chu says.
That's backed up by "some extremely detailed contact tracing" done in the recent preprint from China, says Rasmussen. The researchers "determined that these cases were transmitted primarily through what they called indirect contact, which is most likely inhalation of infectious aerosols [while] breathing shared air, or through direct physical contact," she says.
That means the primary way the virus spreads remains being indoors with someone who is infected and breathing in their droplets or aerosols. With delta, the difference is that the infected person will make many more copies of the virus, faster, which makes it easier to spread.
But in a way, "that's good news," Rasmussen says. "It means that the mitigation measures that we have put in place previously will still work against the delta variant — it's not being transmitted by some other route."
Correction: A previous version of this story incorrectly said that in Massachusetts, about 0.01 percent of all vaccinated people have had confirmed breakthrough COVID-19 cases. The figure is 0.1 percent.
Copyright 2021 NPR. To see more, visit https://www.npr.org.
Your support matters.
You make MPR News possible. Individual donations are behind the clarity in coverage from our reporters across the state, stories that connect us, and conversations that provide perspectives. Help ensure MPR remains a resource that brings Minnesotans together.