The COVID-19 vaccine is primarily designed to prevent serious illness and death—Two purposes for which they continue to work very well. But when the first shots were fired, many also hoped they would be blocked or even vice versa persistent symptoms of COVID, such as fatigue, cognitive dysfunction, chronic pain, and neurological problems.
It is clear now that even people who are fully immunized and healthy can get Long COVID, and recent research shows that vaccines are not the Long COVID shield people want.
Studies have given very different estimates of how protective vaccines against COVID are in the long run. But some of the latest findings suggest rather disappointing protection. In one July report from the UK’s Office for National Statistics, more than 4% of vaccinated and booster adults in the UK infected with Delta, Omicron BA.1 or BA.2 still have symptoms at least 12 weeks later. One Preprints posted online on September 6 (still unreviewed) showed the situation was no better in the US Researchers surveyed people from June to July because the BA.5 variant has taken over. Of those who said they had COVID-19 at least a month earlier, about 20% had symptoms lasting at least four weeks, with slight differences between vaccinated and unvaccinated people. .
That doesn’t mean vaccines are useless against Long COVID. A research review published year Electronic medicine in August analyzed a mixture of peer-reviewed and pre-research studies, six of which looked at whether people who were vaccinated before they were infected had a lower risk of contracting COVID-19 unvaccinated people get sick or not. All six studies concluded that vaccinated people had a lower risk of disease.
At first, it seemed like the vaccine would offer pretty good protection against Long COVID. Some proposed 2021 studies Vaccinated people are up to 50% less likely to get long-term COVID after a breakthrough infection, compared with unvaccinated people infected with COVID-19. But a large study published in Natural Medicine In maybe reached a less encouraging conclusion: it found that vaccinated people were only about 15 percent less likely to develop long-term COVID than unvaccinated people.
Studies hit multiple estimates because of differences in how they were designed, how long they followed people, and how they define long COVIDZiyad Al-Aly, head of research and development at the St. Louis, a clinical epidemiologist at Washington University in St. Louis, and co-author of Natural Medicine research. But regardless of the exact number, “the general theme is that a vaccine offers some protection, but it is never complete,” he said. “Which is part.”
That makes sense, Al-Aly explained. The shots are not designed with chronic symptoms in mind, but rather to reduce the severity of acute illness, offering some secondary benefit for prolonged COVID prevention. Although anyone can develop this condition, people with severe initial cases of COVID-19 are most at risk—So the fact that vaccines tend to keep cases milder than hoped means fewer people will have long-term complications.
In the early stages of vaccine distribution, some anecdotal reports have also raised hopes that vaccination could improve symptoms in people who have long had COVID. But it’s still not clear if that’s true. The authors of Electronic medicine The study review could not find a strong consensus among the 11 studies they analyzed on the topic: seven found that Long COVID patients’ symptoms improved after vaccination, while four The study found that they remained the same or worsened. In a few cases, people have also reported developing persistent COVID-like symptoms after getting vaccinated, even if they didn’t intentionally contract the virus.
New Omicron-specific booster Al-Aly notes that only raises more questions about vaccinations and long-term COVID, as researchers have yet to get a chance to study them. In the future, he hopes researchers will develop vaccines that provide longer-term protection against all variants, block transmission of the virus, and prevent prolonged COVID. Some of these efforts are underway, as scientists work to develop nasal vaccine that can reduce the risk of infection and the photos can target many different coronaviruses at the same time.
However, now, even with immunizations, boosters and previously infected people are not immune to COVID long. Any infection can lead to long-term complications, which underscores the importance of limiting exposure to the virus as much as possible.
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