COVID vaccines linked to reduced long COVID risk in new study
A recent study published on October 2, 2025, indicates that COVID-19 vaccinations significantly lower the risk of developing long COVID. Researchers analyzed data from over 1 million patients, finding a 50% reduction in incidence among vaccinated individuals. The findings highlight ongoing benefits of vaccination even after the acute phase of infection.
On October 2, 2025, scientists from the University of California, San Francisco (UCSF) released a study in the journal Nature Medicine examining the impact of COVID-19 vaccines on long COVID outcomes. The research drew from electronic health records of 1,200,000 adults who tested positive for COVID-19 between 2020 and 2024. Key results showed that individuals who received at least two doses of mRNA vaccines—such as Pfizer-BioNTech or Moderna—experienced a 50% lower risk of long COVID compared to unvaccinated peers. Long COVID was defined as persistent symptoms lasting over 12 weeks, including fatigue, shortness of breath, and cognitive issues.
Lead researcher Dr. Emily Chen stated, 'Our analysis confirms that vaccination not only prevents severe initial illness but also mitigates the debilitating effects of long COVID.' The study controlled for variables like age, comorbidities, and variant strains, with effectiveness holding across Delta and Omicron waves. Among the cohort, 15% of unvaccinated patients developed long COVID, versus 7.5% of vaccinated ones.
Supporting reports from MedPage Today echoed these findings. One article detailed how the vaccine's role in reducing viral persistence could explain the protective effect, citing immune response data from the same dataset. Another piece discussed implications for public health, noting that booster doses further dropped the risk to 40% reduction in high-risk groups.
No major contradictions appeared across sources; all aligned on the 50% figure and sample size. Background context includes prior studies from 2022-2024 that suggested similar links but with smaller cohorts under 500,000. This larger-scale research strengthens the evidence base amid declining vaccination rates post-pandemic.
Implications include renewed calls for booster campaigns targeting vulnerable populations. Health experts caution that while vaccines reduce risk, they do not eliminate it entirely, emphasizing the need for continued monitoring. The study was funded by the National Institutes of Health, with no reported conflicts of interest.