Flu Guide: What to Know This Season
En español | The news these days is all about the much-anticipated COVID-19 vaccine, but there's another existing shot that experts say should be on your radar: Fluzone High-Dose. This injectable flu vaccine, which has been approved by the FDA for folks over the age of 65 for over a decade, has four times the antigens (the flu proteins our immune system recognizes and attacks) than the regular flu vaccine. As of this year, the shot will also be a quadrivalent vaccine, which means it offers even more protection because it protects against four strains of the virus, not just three.
Getting this high-dose vaccine “is very important for older adults, who are more susceptible to flu complications, both because of the decreased immunity that comes with age and also because they are more likely to have other coexisting health conditions, such as heart disease or type 2 diabetes, that leave them more vulnerable to the flu's ill effects,” explains William Schaffner, M.D., an infectious disease specialist at the Vanderbilt University School of Medicine.
Even during non-pandemic times, the flu can be deadly for older adults: About 90 percent of all seasonal flu-related deaths and 50 to 70 percent of flu-related hospitalizations occur among people over the age of 65, according to the Centers for Disease Control and Prevention (CDC). But this year, it's more important than ever that you get vaccinated. “We anticipate a wave of COVID-19 hitting in late fall, right around the same time the flu hits,” Schaffner adds.
Yet despite its apparent benefits, many seniors in the past haven't lined up to get the vaccine. During the 2018-2019 flu season, for example, almost a third of people over 65 skipped it entirely. One of the reasons, says Luke Dogyun Kim, M.D., a geriatrician at the Cleveland Clinic, is the belief that the flu shot isn't effective. It's true that a flu shot won't offer you total protection: A CDC report released this past February found that this past year's flu shot was only about 45 percent effective. But research also shows that any flu vaccine can be the difference between life and death — or a prolonged hospital stay — for many older adults.
A study presented at the Infectious Diseases Society of America's 2019 annual meeting found that adults older than 65 who got the vaccine reduced their risk of ending up in the ICU by 28 percent, and risk of needing a ventilator by 46 percent. Another study of more than 90,000 people published last year in the journal Intensive Care Medicine found that those over 65 who are admitted to an ICU for any reason have less risk of dying and of experiencing a blood clot or brain bleeding if they've been vaccinated. “While the shot can't completely protect against the disease, it does offer some immunity. So if you do get it, your symptoms will most likely be less severe,” Kim adds.
When to get the high-dose shot
The best time to get your shot is from mid-September through October, with October being ideal – it hits the sweet spot between being early enough to ensure your body has enough time to build up immunity and late enough in the season to make sure immunity doesn't wear off by March or April, Schaffner notes. Don't do it much earlier either: The risk of contracting the flu climbs about 16 percent for every 28 days after vaccination, according to a 2019 study published in the journal Clinical Infectious Diseases.
Also try to schedule the shot in the morning if you can. A 2016 study published in the journal Vaccine found that adults over 65 who were given vaccines between 9 a.m. and 11 a.m. had higher levels of protective antibodies than those given the shot between 3 p.m. and 5 p.m. You should also make sure you got the pneumococcal vaccine PPSV23 in order to reduce risk of pneumonia; last November, the CDC stopped routinely recommending that people over the age of 65 get the second pneumonia vaccine, PCV13, unless they have an immunocompromising condition, cerebrospinal fluid (CSF) leaks or a cochlear implant.
Shortages aren't expected — but what to ask for if supplies run short
All flu vaccines, including the high-dose one, are free with Medicare Part B. While in the past — including last year — there have been reports of vaccine production problems that have led to vaccine shortages, this year manufacturers are optimistic that they will have plenty to go around, Schaffner says. If for some reason, you can't get Fluzone, there's another flu vaccine, Fluad, that's also approved for older adults. This vaccine contains an adjuvant, which is an ingredient added to promote a stronger immune response.
A February 2020 study published in the Journal of Infectious Diseases found that among Medicare beneficiaries 65 years and older, Fluad, like Fluzone, provided greater protection against flu-related hospitalizations than standard-dose egg-based flu vaccines. While there have been no randomized studies comparing both vaccines head-to-head against influenza, “anecdotally, we have found that high-dose vaccines offer [older adults] better protection,” Kim says. But whatever you do, don't put off your flu shot — make sure you get any vaccine that's available. “Some protection is better than none,” Kim adds.
Keep in mind that both the high-dose and adjuvanted flu vaccines can cause more of the temporary, mild side effects that can occur with standard-dose shots (think pain, redness or swelling at the injection site, as well as headache and muscle aches for a day or two). This is just a sign that the vaccine is working like it should, Kim says.
Remember: It's never too late to get the vaccine, even once the flu season starts. “The flu usually peaks until February and then can circulate until April,” Schaffner adds. Just realize that even if you do get jabbed, you still need to take preventive steps like wearing a mask, practicing social distancing and washing hands frequently in order to protect yourself against both flu and COVID-19.