Public health authorities are encouraging everyone to get a flu shot this year. This goes beyond the usual advice to get protection from seasonal influenza. Experts worry that people who contract two respiratory infections at the same time could be in grave danger. Of course, someone catching COVID-19 just as they recover from flu might succumb. Moreover, the authorities don’t want lots of influenza patients to overwhelm hospitals when COVID-19 cases start to climb. In addition, the symptoms of the flu and COVID-19 are quite similar, especially at the start of the infections. Health care providers and patients alike may have a hard time distinguishing between them. While antiviral drugs like Tamiflu should help people recover more quickly from influenza, they aren’t likely to do anything against COVID-19.
Another Argument Why You Should Get a Flu Shot:
If you need an additional incentive to get a flu shot, think about this. Dutch scientists suspect that influenza vaccinations might provide some protection against COVID-19 (MedRxiv, October 2020). In a preprint, they describe how the quadrivalent flu vaccine seems to rev up the innate immune system. In fact, this phenomenon has a name–trained immunity. That’s in addition to the vaccine’s main job of the adaptive immune system to recognize and repel influenza viruses specifically.
Vaccinated Health Care Workers Less Prone to COVID-19:
According to the research, Dutch hospital workers who got a flu shot in late 2019 were less likely to catch COVID-19 than those who did not get vaccinated. The immunization was a quadrivalent vaccine using four different strains of inactivated virus. Vaccinated employees were about 40 percent less likely to catch COVID-19.
This is an observational study, not a randomized controlled trial. (Randomized controlled trials are the most reliable type of study.) In addition, it has not yet undergone peer review. Nonetheless, if the flu vaccine offers any protection against COVID-19 as well as the flu, that would be a bonus. A vaccine for SARS-CoV-2 will probably not be finalized, approved and widely distributed for at least several more months.