COVID-19 vaccines were designed primarily to prevent severe disease and death—two purposes for which they continue to work very well. However, people had hoped the shots would also block, or reverse, symptoms of Long COVID. This included fatigue, cognitive dysfunction and chronic pain.
By now, it’s clear that even people who are fully vaccinated and boosted can get Long COVID, and recent research suggests that vaccines aren’t the Long COVID shields people wished for.
Many studies have produced very diverse estimates of the protection offered by vaccines against Long COVID. However, some recent findings show a very disappointing level of protection. In one July report from the U.K.’s Office for National Statistics, more than 4% of vaccinated and boosted adults in the U.K. who were infected by Delta, Omicron BA.1, or BA.2 still had symptoms at least 12 weeks later. A preprint posted online on Sept. 6 (which has not yet been peer-reviewed) suggests the situation isn’t any better in the U.S. Researchers surveyed individuals from June through July to see if the BA.5 version was winning. Among those who said they’d had COVID-19 at least a month earlier, roughly 20% had symptoms that lasted at least four weeks, with little difference between vaccinated and unvaccinated people.
That’s not to say vaccines are useless against Long COVID. In a research review, eClinical medicine In August, we analyzed six peer-reviewed as well as preprint studies. Six of these looked at the risk of Long COVID in people who had been vaccinated prior to getting infected. Six studies all concluded that people who are vaccinated have a lower chance of getting sick.
Learn More: Is it possible to mix and match Omicron boosters? Here’s What to Know
At first glance, vaccines appeared to be quite protective against Long CoVID. A 2021 study showed that people who were vaccinated had 50% lower chances of developing Long COVID from a breakthrough infected. This was in contrast to people who weren’t vaccinated and those who contracted COVID-19. However, a huge study that was published in Nature Medicine In May, the study came to a more encouraging conclusion. It found that people who had been vaccinated were about 15% less likely than those who hadn’t.
Because of variations in the way studies were constructed, tracked individuals for how long, and defined Long COVID, estimates have varied widely, according to Dr. Ziyad al-Aly. He is chief of research at Veterans Affairs St. Louis Health Care System and clinical epidemiologist at Washington University. Nature Medicine study. But regardless of the exact numbers, “the common thread is vaccines do offer some protection, but it’s never complete,” he says. “It’s partial.”
Al-Aly explained that this makes perfect sense. The shots weren’t designed with chronic symptoms in mind, but rather to reduce the severity of acute disease, which offers some secondary benefits for Long COVID prevention. Though anyone can develop the condition, people who have severe initial cases of COVID-19 are at highest risk—so the fact that vaccines tend to keep cases milder hopefully means fewer people will develop lasting complications.
Some anecdotal reports suggested that shots might improve the symptoms of Long COVID patients. But it’s still not clear whether that’s true. Authors of eClinical medicine research review couldn’t find a strong consensus in the 11 studies they analyzed on this topic: seven found that Long COVID patients’ symptoms improved after vaccination, while four found that they stayed the same or worsened. In rare cases, people have also reported developing Long COVID-like symptoms after getting vaccinated, even if they hadn’t knowingly had the virus.
The new Omicron-specific boosters only raise more questions about vaccination and Long COVID, Al-Aly notes, since researchers haven’t had a chance to study them yet. Al-Aly hopes vaccines can be designed that will provide more long-lasting protection from all viruses and block their transmission. These efforts include the development of nasal vaccines to reduce infection risk and shot that targets multiple coronaviruses.
For now, though, even vaccinated, boosted, and previously infected people aren’t immune to Long COVID. There are potential complications that could linger from an infection, so it is important to limit your exposure as much as you can.
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