This year's influenza ("flu") season, which should kick off sometime in October, rev up in November, and last until spring, will be made more treacherous than ever by the concurrent COVID-19 pandemic (cases of which are currently surging in many parts of the nation). The coincidence of infections by the two viruses in the population has the potential to be a perfect storm.
There have been more than 7 million confirmed cases and about 210,000 deaths from COVID-19 in the U.S. this year, and public health experts are expecting an uptick in cases as winter approaches and people tend more often to be in crowded, poorly ventilated, indoor spaces.
The morbidity of flu varies significantly from year to year. The Centers for Disease Control and Prevention (CDC) estimates that it has caused millions of deaths, hundreds of thousands of hospitalizations, and tens of thousands of deaths every year since 2010. As shown in the figure below, the morbidity and mortality vary significantly from year to year. If this flu season is at the high end of the range, hospitals contending with large numbers of admissions for flu, in addition to COVID-19 patients, could well be overwhelmed.
The director of the CDC, Dr. Robert Redfield, has said his biggest fear is that doctors' offices, clinics, and hospitals will be stressed from the two respiratory diseases striking simultaneously, because "when the health system gets overwhelmed, we find that with COVID-19, this is where the mortality seems to be the greatest."
That makes it especially imperative to prevent infections from both viruses with the tools at our disposal. The preventative measures recommended for COVID-19, which include wearing a mask, social distancing, frequent hand-washing, and avoiding crowded, poorly ventilated spaces, also works for the flu. There is another potent weapon to prevent the flu: vaccines. The CDC hopes to boost vaccination rates to 65% of American adults this flu season — about 25 percentage points higher than in a typical year.
The American Medical Association has listed a number of points about flu vaccination that might help to reduce "vaccine hesitancy." Some of these are discussed below.
The vaccine cannot give you the flu. All the flu vaccines that are injected consist of non-infectious fragments of the virus. The nasal spray (which is approved for administration to people from ages 2-49) consists of attenuated, or weakened, viruses, such that it, too, is non-infectious. Swelling and pain at the injection site, muscle aches, some fatigue, or a low-grade fever sometimes follows administration of flu vaccines, but those signs and symptoms are short-lived.
Vaccine can reduce flu risk by up to 60%. The effectiveness of flu vaccines is usually in the range of 40-60%, which is important not only for protecting individuals by preventing a potentially lethal illness, but for preventing hospital capacity overload. Even when flu doesn't require hospitalization, it's an unpleasant and debilitating illness, the signs and symptoms of which include high fever, chills, muscle aches, cough, congestion, runny nose, headaches, and fatigue.
Getting flu vaccine is more important than ever. It's possible to be infected with flu and SARS-CoV-2 (the virus that causes COVID-19) simultaneously or sequentially, which is especially dangerous, because both can damage the lungs, compounding the effects of infection.
Flu vaccination is especially important in the very young and old. Mortality from the flu is especially high in the very young and elderly, so it is especially important for them to be vaccinated. There are high-dose versions of the injectable vaccines for seniors, whose immune response is generally less robust than that in younger people. For people who are averse to shots (and are age 2 through 49), nasal spray versions of flu vaccine are available.
Get vaccinated as soon as possible. As noted above, the flu season is about to begin, and it takes roughly two weeks for the immune system to generate an optimal immune response. And by the way, even if you have a mild cold or other illness, as long as you don't have a fever, you can still be vaccinated.
Do it for yourself and others. "There are benefits to us as individuals: We're less likely to get the flu. Even if we do develop the flu, we're less likely to need to be hospitalized and it tends to be less severe if you get the vaccine," said Dr. Kate Kirley, a family physician and director of chronic disease prevention at the AMA. "It is also about protecting others — your family, friends, community members."
As to where to go, "There are plenty of options for where to get the shot or nasal spray immunization," according to pediatric allergist Dr. Michael Mellon. "They include your primary-care physician's office, HMO (health maintenance organization), public health clinic, or the local pharmacy. Usually, they have designated areas for flu vaccination, so you're not exposed to people who are there for other reasons."
But the important thing, he concludes, is, "Get it!"
Henry I. Miller, a physician and molecular biologist, is a senior fellow at the Pacific Research Institute. He was the founding director of the FDA's Office of Biotechnology and the co-discoverer of a critical enzyme in the influenza virus.