According to a large new study published in the New England Journal of Medicine, vaccination has been found to decrease the likelihood of developing long Covid. The study, which compared the health records of over 440,000 Covid-19 patients from the Veterans Affairs healthcare system with records of more than 4 million uninfected individuals, also discovered that while the risk of serious complications has diminished, it hasn't completely disappeared as new coronavirus variants emerged.

The analysis revealed that cases of long Covid, also known as PASC (post-acute sequelae of severe acute respiratory syndrome coronavirus 2), decreased among all participants during the Delta and Omicron eras of the pandemic. However, vaccinated individuals saw a nearly twice as significant decline in long Covid cases when the Omicron variant dominated. This new data comes as the country experiences a summer resurgence in Covid cases and as Pfizer and Moderna prepare to roll out vaccines updated against newer strains in August.

Experts have hailed the study for validating the suspicion that the incidence of PASC decreases over time and in relation to new variants. Hilary Goldberg, the clinical director of pulmonary and critical care medicine at Brigham and Women's Hospital in Boston, noted that the study also affirms the protective effect of vaccination in preventing the development of long Covid, a question that had remained unsettled.

The study's findings indicate that, during the Delta variant era, the rate of long Covid among unvaccinated individuals was 9.51 out of 100, compared to 5.34 out of 100 for vaccinated individuals. With the onset of the Omicron era, the gap widened even further, with 7.76 out of 100 unvaccinated individuals and only 3.5 out of 100 vaccinated individuals acquiring long Covid.

While the study emphasizes the effectiveness of vaccines, senior author Ziyad Al-Aly, chief of research at the VA St. Louis Health Care System and a clinical epidemiologist at Washington University in St. Louis, cautions that vaccines do not completely eliminate the risk of long Covid. He emphasizes the importance of further research to understand the interplay between viral infection, immunological changes, and vaccine coverage.

The study also highlights the evolving nature of long Covid symptoms. While debilitating fatigue was previously a hallmark, more recent gastrointestinal, metabolic, and musculoskeletal problems have surpassed fatigue among unvaccinated individuals. The study measured the impact of long Covid in ten disease categories, including cardiovascular, mental health, and neurologic issues.

The study's authors utilized statistical analysis to determine that vaccines accounted for 72% of the lower incidence of long Covid among vaccinated individuals, while changes in variants and improved medical care contributed 28% to the decline.

However, the study did not provide information on the number of vaccinations received by participants, leaving gaps in the data. Concerns about the risk of reactivation or worsening of PASC symptoms from vaccination compared to infection remain unanswered, highlighting the need for further information to guide patient decision-making.

Despite the declining risk of long Covid, experts stress that the threat is still significant. Vaccination, combined with efforts to avoid Covid-19, remains the best defense against developing long Covid. As the country battles vaccine hesitancy and faces increasing cases of Covid-19, it is crucial to educate and counsel patients and physicians to increase vaccine acceptance and address the ongoing challenge of long Covid.

Overall, this groundbreaking study provides valuable insights into the benefits of vaccination in reducing the risk of long Covid. However, further research is needed to fully understand the complex relationship between viral variants, immunological responses, and long Covid to effectively address this debilitating condition.