Flu Vaccine May Protect Against Severe Effects of COVID-19

The influenza vaccine has the potential to provide vital protection against severe effects of COVID-19, according to new study results from investigators at the University of Miami Leonard M. Miller School of Medicine in Florida.

The study, which analyzed 37,377 patient records on a global scale, strongly suggests that getting the annual flu vaccine reduces the risks of deep vein thrombosis (DVT), sepsis, and stroke in patients with COVID-19.

Those with COVID-19 who have been vaccinated against the flu were also significantly less likely to visit the emergency department (ED) and be admitted to the intensive care unit (ICU), according to the study results.

“Only a small fraction of the world has been fully vaccinated against COVID-19 to date, and with all the devastation that has occurred due to the pandemic, the global community still needs to find solutions to reduce morbidity and mortality,” senior study author Devinder Singh, MD, chief of the Division of Plastic Surgery and professor of clinical surgery at the Miller School of Medicine, said in a statement.

The study results show that patients with COVID-19 who had not had the flu vaccine were up to 20% more likely to be admitted to the ICU. Further, they were significantly more likely to develop sepsis (45%), have a stroke (58%), develop DVT (40%), or visit the ED (58%), and the risk of death was not reduced.

In addition, the investigators were able to calculate how many patients with COVID-19 would need to receive the influenza vaccine to avoid an adverse outcome. They found that 176 patients would need to have received the flu vaccine to prevent 1 ED visit within 120 days of testing positive for COVID-19. In addition, 286 patients were needed to have received their flu vaccine to prevent 1 case of sepsis. For every 440 patients who were updated on their flu vaccine, 1 ICU admission was prevented.

Although these results suggest that the flu vaccine may protect against several severe effects of COVID-19, the study authors strongly recommend that everyone should get a COVID-19 vaccination in addition to their annual flu vaccine.

Although more research is needed, the investigators said that they hope the flu shot can provide increased protection in countries where the COVID-19 vaccine is in short supply or help protect against new breakthrough cases in individuals who are already vaccinated against COVID-19.

REFERENCE

New study: flu shot protects against severe effects of COVID-19. University of Miami Leonard M. Miller School of Medicine. August 4, 2021. Accessed August 5, 2021. https://www.eurekalert.org/news-releases/924379