Data from people infected with SARS-CoV-2 early in the pandemic add to growing evidence suggesting that vaccination can help to reduce the risk of long COVID.
Researchers in Israel report that people who have had both SARS-CoV-2 infection and doses of Pfizer–BioNTech vaccine were much less likely to report any of a range of common long-COVID symptoms than were people who were unvaccinated when infected. In fact, vaccinated people were no more likely to report symptoms than people who’d never caught SARS-CoV-2. The study has not yet been peer reviewed.
“Here is another reason to get vaccinated, if you needed one,” says co-author Michael Edelstein, an epidemiologist at Bar-Ilan University in Safed, Israel.
People with the debilitating condition called long COVID continue to experience symptoms — such as fatigue, shortness of breath and even trouble concentrating — weeks, months or years after SARS-CoV-2 infection. Some estimate that up to 30% of infected people, including many who were never hospitalized, have persistent symptoms.
Vaccination reduces long COVID’s incidence by preventing people from getting infected in the first place. In theory, the shots could also protect against the condition by minimizing the length of time the virus has free rein in the body during breakthrough infections. But so far, the few studies that have looked into whether vaccines protect people from long COVID have had mixed results, says Akiko Iwasaki, a viral immunologist at the Yale School of Medicine in New Haven, Connecticut.
The researchers compared the prevalence of each symptom to self-reported vaccination status and found that fully vaccinated participants who had also had COVID-19 were 54% less likely to report headaches, 64% less likely to report fatigue and 68% less likely to report muscle pain than were their unvaccinated counterparts.
Edelstein says his team’s study is the most “comprehensive and precise” to date on vaccination and long COVID, and that the results echo those of other research, including a UK-based study from last September that found that vaccination halved the risk of long COVID.