Data from people infected with SARS-CoV-2 early in the pandemic adds to growing evidence suggesting that vaccination can help reduce the risk of long COVID1.
Researchers in Israel report that people who were infected with SARS-CoV-2 and received doses of the Pfizer-BioNTech vaccine were much less likely to have any of the common symptoms of long COVID than people who were not vaccinated when they became infected. In fact, vaccinated people were no more likely to report symptoms than people who had never contracted SARS-CoV-2. The study has not yet been peer-reviewed.
People who have been vaccinated and have had COVID-19 are less likely to report fatigue and other health problems than unvaccinated people.
"This is another reason to get vaccinated, if you need to," says co-author Michael Edelstein, an epidemiologist at Bar-Ilan University in Safed, Israel.
Association between vaccination status and the reported incidence of post-acute COVID-19 symptoms in Israel: a cross-sectional study of patients examined between March 2020 and November 2021
Background
Long COVID is a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection syndrome characterized by failure to recover for several weeks or months after the acute episode.
The long-term effectiveness of vaccines against COVID-19 symptoms is not well known. We determined whether vaccination was associated with the incidence of long-term symptom reporting after COVID-19 infection.
Methods
Individuals who underwent PCR testing for SARS-CoV-2 infection at participating hospitals between March 2020 and November 2021 were invited to complete an online questionnaire that included baseline demographic data, details of their episode acute and information about the symptoms they were currently experiencing.
Using binomial regression, we compared vaccinated individuals with unvaccinated and uninfected individuals on self-reported symptoms following acute infection.
Results
951 infected and 2437 uninfected individuals were included . Of those infected, 637 (67%) were vaccinated.
The most frequent symptoms were: fatigue (22%), headache (20%), weakness (13%) and persistent muscle pain (10%).
After adjusting for follow-up time and baseline symptoms, those who received two doses were less likely than the unvaccinated to report any of these symptoms by 64%, 54%, 57% and 68%, respectively, (hazard ratios 0.36, 0.46, 0.43, 0.32, p<0.04 in the indicated sequence).
Those who received two doses were no more likely to report any of these symptoms than individuals who did not report any prior SARS-CoV-2 infection.
Conclusions Vaccination with at least two doses of the COVID-19 vaccine was associated with a substantial decrease in reporting of the most common post-agonic symptoms of COVID-19, bringing it back to baseline. Our results suggest that, in addition to reducing the risk of acute disease, COVID-19 vaccination may have a protective effect against long COVID. |
