The study was the largest of its kind looking at the flu shot and COVID-19.
Results from the study were published in the journal PLOS ONE.
“Having access to the real-time data of millions of patients is an incredibly powerful research tool,” Devinder Singh, senior author on the study said. “Together with asking important questions, my team has been able to observe an association between the flu vaccine and reduced morbidity in COVID-19 patients.”
For the study, the team of investigators analyzed de-identified records of 74,754 patients from the TriNetX research database. The patients were divided into 2 groups which were matched for factors that could influence their risk of susceptibility to severe COVID-19.
The first group must have received a flu vaccination 2 weeks to 6 months before being diagnosed with COVID-19. The second group had a confirmed infection with COVID-19 but were not vaccinated against the flu.
Findings from the study showed that those who did not receive the flu vaccine were up to 20% more likely to have been admitted to the ICU. They were also 58% more likely to visit the emergency department, 45% more likely to develop sepsis, 58% more likely to have a stroke and 40% more likely to have a DVT.
Additionally, the investigators found that 176 patients would need to get the flu vaccine to avoid 1 adverse outcome.
“Continued promotion of the influenza vaccine also has the potential help the global population avoid a possible ‘twindemic’ — a simultaneous outbreak of both influenza and coronavirus,” Susan Taghioff, lead author on the study said. “Regardless of the degree of protection afforded by the influenza vaccine against adverse outcomes associated with COVID-19, simply being able to conserve global health care resources by keeping the number of influenza cases under control is reason enough to champion continued efforts to promote influenza vaccination worldwide.”
