Just in time for this summer wave of Covid-19 infections, a new study brings fresh insight into the evolving risk of long Covid. Researchers assessed changes in the likelihood of developing long Covid since the beginning of the pandemic and highlighted the continued role vaccination plays in reducing such risk in a report published Wednesday in the New England Journal of Medicine.
Decline in Long Covid Risk:
The latest research shows that, though it has declined since the beginning of the pandemic, especially in the unvaccinated population, diagnosed persons still stand at considerable risk for long Covid. According to the federal Agency for Healthcare Research and Quality, about 7% of adults in the United States—some 18 million people—have suffered from long Covid. This, against an estimated cost burden of $3.7 trillion attributed to long Covid, as calculated by Harvard economist David Cutler back in the year 2022.
A new study using sophisticated machine learning and rich data from the Department of Veterans Affairs provides a broad view of trends in long Covid. Researchers at Washington University in St. Louis and the VA Health System examined cases from different pandemic phases: the pre-vaccine era, the surge of the Delta variant, and the period of the Omicron variant.
Vaccination:
Vaccination against Covid-19 has been among the most prominent factors reducing the risk of long Covid. During summer 2021, when the surge in the cases was due to the Delta variant, there was approximately half the chance of long Covid in vaccinated individuals. For the unvaccinated, though, this risk remained very high—about 10% of the unvaccinated who contracted the virus reported lingering symptoms.
The Omicron variant, which began its spread toward the end of 2021, further influenced long Covid outcomes. Among vaccinated individuals, it slid to a risk of 3.5 percent, and the risk was 7.7 percent among unvaccinated people, the study revealed. This shows vaccines staying effective against long Covid but with considerable risk.
Study Limitations and Future Research:
The study has some limitations, while valuable in its insights. Most participants whose data were used in the research were White male veterans, and it was therefore underrepresented in terms of the general population. Moreover, the study did not consider the influence of booster doses or post-infection immunity—topics Dr. Ziyad Al-Aly, senior author, is planning to research next.
According to Dr. Al-Aly, vaccines were responsible for maybe three-quarters of the risk reduction in long Covid since it was first described in early days of the pandemic. Vaccines are said to have an important effect on boosting the immune system to rid itself of the virus and prevent long-term symptoms.
The Need to Continue Vaccination:
That also underscores the very critical role of vaccination in fighting long Covid. According to Dr. Hector Bonilla, who is running Stanford’s Post-Acute Covid-19 Syndrome Clinic, vaccines are still very fundamental to preventing long Covid. While new patients with long Covid have decreased, continuous vaccination is still to be carried out to further drive the risk down and ensure public health.
The Evolving Virus and Its Impact:
But beyond vaccination, changes to the virus itself have helped put a downward pressure on long Covid risk. According to Dr. Al-Aly, how much the virus has evolved causes a lower risk of long Covid compared with earlier pandemic strains. Still, about 3 of every 100 vaccinated people develop the condition, so it remains quite a problem.
A Call for Continued Action:
Experts agree that, after all the progress, long Covid is still widespread. Dr. Daniel Griffin from Columbia University said that the ongoing battle to comprehend new cases of long Covid explains why it’s a condition that still needs research and funding. Dr. Al-Aly implores that an aggressive response to long Covid is needed, focusing on coordinated care with an overall plan to address this ongoing crisis.
Conclusion:
The risk of long Covid, though subsiding over time, is still a serious concern, more so among the unvaccinated. Vaccination and continued research are very critical in taming the effect of long Covid and helping victims.