New York City veterinarian Erin Kulick used to be a weekend warrior. Only 2½ years ago, the 38-year-old new mother played ultimate Frisbee and flag football with friends. She went for regular 30-minute runs to burn off stress.
Now, Dr. Kulick is usually so exhausted, she can’t walk nonstop for 15 minutes. She recently tried to take her 4-year-old son, Cooper, to the American Museum of Natural History for his first visit, but ended up on a bench outside the museum, sobbing in the rain, because she couldn’t even get through the first hurdle of standing in line. “I just wanted to be there with my kid,” she said.
Dr. Kulick got sick with COVID-19 at the start of the pandemic in March 2020, 9 months before the first vaccine would be approved. Now she is among the estimated one in five infected Americans, or 19%, whose symptoms developed into long COVID.
Dr. Kulick also is now vaccinated and boosted. Had a vaccine been available sooner, could it have protected her from long COVID?
Evidence is starting to show it’s likely.
“The best way not to have long COVID is not to have COVID at all,” said Leora Horwitz, MD, a professor of population health and medicine at New York University. “To the extent that vaccination can prevent you from getting COVID at all, then it helps to reduce long COVID.”
And People with more serious initial illness appear more likely to have prolonged symptoms, but those with milder disease can certainly get it, too.
“You’re more likely to have long COVID with more severe disease, and we have ample evidence that vaccination reduces the severity of disease,” Dr. Horwitz said. “We also now have quite a lot of evidence that vaccination does reduce your risk of long COVID – probably because it reduces your risk of severe disease.”
There is little consensus about how much vaccines can lower the risk of long-term COVID symptoms, but several studies suggest that number lies anywhere from 15% to more than 80%.
That might seem like a big variation, but infectious disease experts argue that trying to interpret the gap isn’t as important as noticing what’s consistent across all these studies: “Vaccines do offer some protection, but it’s incomplete,” said Ziyad Al-Aly, MD, chief of research and development at the Veterans Affairs St. Louis Health Care System. Dr. Al-Aly, who has led several large studies on long COVID, said focusing on the fact that vaccines do offer some protection is a much better public health message than looking at the different levels of risk.
“Vaccines do a miraculous job for what they were designed to do,” said Dr. Al-Aly. “Vaccines were designed to reduce the risk of hospitalization ... and for that, vaccines are still holding up, even with all the changes in the virus.”
Still, Elena Azzolini, MD, PhD, head of the Humanitas Research Hospital’s vaccination center in Milan, thinks some studies may have underestimated the level of long COVID protection from vaccines because of limits in the study methods, such as not including enough women, who are more affected by long COVID. Her recent study, which looked at 2,560 health care professionals working in nine Italian centers from March 2020 to April 2022, focused on the risk for healthy women and men in their 20s to their 70s.
In the paper, Dr. Azzolini and associates reported that two or three doses of vaccine reduced the risk of hospitalization from COVID-19 from 42% among those who are unvaccinated to 16%-17%. In other words, they found unvaccinated people in the study were nearly three times as likely to have serious symptoms for longer than 4 weeks.
But Dr. Azzolini and Dr. Al-Aly still say that, even for the vaccinated, as long as COVID is around, masks are necessary. That’s because current vaccines don’t do enough to reduce transmission, said Dr. Al-Aly. “The only way that can really help [stop] transmission is covering our nose and mouth with a mask.”