Dr. Brian Conway has advice for anyone thinking about getting a flu shot this fall.
“Run! Don’t walk to get your flu shot,” he said, speaking from his office at the Vancouver Infectious Disease Centre. “I think there is great consensus behind the statements that there will be a significant influenza season going forward.”
Getting your flu shot may do more than just protect you against the influenza virus — it may also prove to be protective against the most severe effects of COVID-19, according to an extensive new analysis presented online at the European Congress of Clinical Microbiology & Infectious Diseases (ECCMID) in August.
The study, titled “Examining the potential benefits of the influenza vaccine against SARS-CoV-2: A retrospective cohort analysis of 74,754 patients,” was published in the peer-reviewed scientific journal PLoS One on August 3rd. This was the largest study of its kind and analyzed deidentified patient records from around the world, which strongly suggested that the annual flu shot reduces the risks of stroke, sepsis, and deep vein thrombosis (DVT) in patients with COVID-19. Patients with COVID-19 who had been vaccinated against the flu were also significantly less likely to visit the emergency department or be admitted to intensive care.
“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,” said senior study author Devinder Singh, M.D., a professor of clinical surgery at the Miller School.
“Having access to the real-time data of millions of patients is a powerful research tool,” added Dr. Singh, who conducted the study with medical residents Susan Taghioff and Benjamin Slavin, M.D., both of whom were lead authors. “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.”
“Continued promotion of the influenza vaccine has the potential to help the global population avoid a possible ‘twindemic’ — a simultaneous outbreak of both influenza and coronavirus,” Taghioff said. “Regardless of the degree of protection afforded by the influenza vaccine against adverse outcomes associated with COVID-19, conserving global health care resources by keeping the number of influenza cases under control is reason enough to champion efforts to promote influenza vaccination worldwide.”
The egregious flu season researchers see looming on the horizon is due, in part, to last fall and winter when influenza was effectively eliminated in British Columbia and across Canada, thanks to COVID-19 health orders preventing gatherings and travel, while promoting physical distancing, mask-wearing and hand-washing.
But, with social life now returning to normal, zero flu last season will have consequences this season: the population is likely now more susceptible to the virus.
“People don’t have any built-up immunity that they might have [developed] from a flu season last year, or from getting their [flu] shots last year, or both,” said Conway. “So we’ll go from the best year on record for influenza to something other than that.”
Two companies, Moderna and Novavax, have announced they are working on a combined flu and COVID-19 vaccine, which Conway believes will be the future.
“There’s an expectation that COVID is going to be around for a while. Flu, obviously, has been around for a long while and will be around and we’re just going to be vaccinating people for both on a yearly basis,” Conway said. “But for now, please run and get your flu shot.”
The B.C. Centre for Disease Control said the flu shot is expected to be widely available by mid-October, either at your doctor’s office or through your local pharmacy.
