A new meta-analysis of studies involving more than 14 million people published in the Journal of Infection shows that COVID-19 vaccination is associated with a lower risk of developing long COVID, with two doses reducing the odds by 24% and one dose reducing the odds by 15%.

In the 25 studies published up to February 2024 that were included for analysis, long COVID was defined as persistent symptoms at 3 months or beyond, and all studies compared long-COVID symptoms between vaccinated and unvaccinated groups, with the number of doses received by participants specified. All studies included were observational trials and included in total 14,128,260 participants.