Why Older Adults Need Special Flu Shots
If you’re 65 or older, ask for Fluzone High-Dose, Fluad, or Flublok when you get vaccinated this year
By Catherine Roberts
For many years, people who are 65 or older have had the option to get a flu shot that’s specially formulated for them.
But the Centers for Disease Control and Prevention declined to recommend that older adults get these shots instead of the standard flu shot options. This flu season, that has changed.
The CDC is now recommending that people 65 or older try to seek out one of these specially formulated vaccines.
“That’s a very exciting change,” says Jenna Bartley, PhD, an assistant professor in the department of immunology who’s with the Center on Aging at UConn Health. “What we’ve seen in multiple research studies now is that both the high-dose and the adjuvanted flu vaccine have superior antibody induction in older adults and result in overall better protection from flu.”
The change reflects an extensive review of the evidence on how well the different kinds of flu vaccines work for older people, according to Alicia Fry, MD, chief of the CDC’s Epidemiology and Prevention Branch. The picture that emerged from this review made clear what scientists had long suspected: Some vaccines provide better protection against the flu than others for older adults, and for the best protection during the flu season, older people should seek them out.
The season has already begun, so if you haven’t gotten your flu vaccine yet, the time is now. And if you’re 65 or older, you should try to find one of these three shots: Fluzone High-Dose, Fluad, or Flublok. Here’s why.
What’s Different About These Flu Vaccines?
One thing to note: These vaccines have the word “quadrivalent” in their name. That means they provide protection against four different strains of influenza. A few years ago, “trivalent” vaccines, which protect against three strains of flu, were more common. But today, all the flu shots available are quadrivalent types.
Fluzone High-Dose Quadrivalent: Fluzone High-Dose has been available in the U.S. since 2010. This vaccine contains four times the amount of flu antigen—or the molecule that provokes the immune system to create antibodies against the flu—as the standard flu shot.
According to the CDC, of the three vaccines recommended for older adults, this vaccine has the most evidence supporting its superior efficacy over the regular shot. For example, a 2014 study in The New England Journal of Medicine found that this high-dose flu shot was 24 percent more effective at preventing the flu in people 65 and older than the standard vaccine.
Fluad Quadrivalent: It has been available in the U.S. since 2015 (and it’s been used widely in Europe since the late 1990s). This vaccine contains the same amount of flu antigen as the standard shot but also contains something called an adjuvant. That’s a substance that’s added to a vaccine in order to provoke a stronger response from the immune system.
A 2020 study in the journal Vaccines found that during the 2017-2018 flu season in the U.S., Fluad provided better protection than the standard shot against flu-related visits to a doctor and against flu- and pneumonia-related hospitalizations. Other evidence from Europe, where this vaccine has been in use for a longer period of time, shows that it consistently outperforms the standard shot in older people.
Flublok Quadrivalent: Flublok was first licensed for use in the U.S. in 2013. Unlike Fluzone and Fluad, it’s also approved for use in younger adults and is recommended for older people. This shot is what’s known as a recombinant vaccine, which means it’s made using a different technological process than most other flu shots.
Flublok is similar to Fluzone High-Dose in that it contains more flu antigen, although Flublok contains only three times (rather than four times) the amount of flu antigen as the standard vaccine. But don’t think that means it’s less effective than the other high-dose vaccine. A 2017 study in The New England Journal of Medicine found that it reduced the chances of catching a flu-like illness by 30 percent among people 50 and older compared with the standard vaccine.
Which Flu Shot Is the Best?
There isn’t enough evidence yet to indicate whether one of these three vaccines provides superior protection over the other for older people.
A CDC advisory committee reviewed all the research it could find comparing these vaccines. It found only one study that suggested the recombinant shot (Flublok) might have a slight edge in effectiveness over the high-dose and adjuvanted vaccines, though that study covered only a single flu season. The agency considered this low-quality evidence, in part due to the possibility of bias in the results.
As for side effects from these shots, they are generally mild and include symptoms like arm pain, head or muscle aches, and malaise. Research has found that these side effects tend to occur more frequently among people who receive the Fluzone High-Dose and Fluad shots than people who get standard flu vaccines. However, as with other flu vaccines, these side effects usually aren’t severe. For people who receive the Flublok shot, side effects seem to appear about as often as they do with standard vaccines.
Still, overall, the CDC says there’s no reason to seek out one of these three vaccines over the other two, and your provider may offer just one of them.
Why You Need a Special Vaccine Later in Life
As with COVID-19, those who are most at risk for getting seriously sick with the flu are older people. “They have more hospitalizations than any other age groups; they have more deaths than any other age groups. So it’s very important that we do everything possible to protect this very vulnerable group,” says Fry at the CDC.
One factor: Your immune system weakens with age. To mount an immune response to a vaccine, many different types of cells in your body work in an orchestrated way to create protection against a disease. “As you get older, that communication between cells doesn’t work as well. We have this general dysregulation of the immune system,” says Bartley from the Center on Aging at UConn Health. That means older people may not develop as much protection against flu with the standard shot as a younger person would. The high-dose and adjuvanted shots are meant to compensate for that less robust immune response and provoke a higher level of protection in older people.
Fluzone High Dose and Fluad are available only for people 65 and older. If you’re younger than 65, you generally don’t need the extra boost to your immune system. For people who aren’t immunocompromised, your system will probably produce a good immune response from the standard shot, and getting one of the others might only invite additional side effects for little extra benefit, Bartley says.
A few preliminary studies have suggested that the Fluzone High-Dose vaccine may also provide a better immune response in certain groups of immunocompromised people, including those who have received or donated organs or stem cells, and people with HIV. Those studies only looked at the immune response as measured in participants’ blood, however, rather than at how effective Fluzone was at preventing actual cases of the flu, and more research is needed on the high-dose vaccine’s effectiveness in these people. If you’re immunocompromised, you may want to ask your doctor about the best flu vaccine strategy for you.
Flublok, also a higher-dose vaccine, is approved for all adults 18 and up. So while it’s an option for younger adults, it’s only preferentially recommended for people 65 and older. Some researchers have hypothesized that this shot might provide better protection for younger adults, too, but existing evidence doesn’t show that yet. That’s why the CDC’s Advisory Committee on Immunization Practices (ACIP) only preferentially recommended it for older people, Fry says. So far we only have data that it provides superior protection in that age group.
Where Do You Find These Shots?
Check to see if the doctor’s office or pharmacy where you usually get your annual flu vaccine carries them. If they don’t have one of these three, it’s worth trying some other places. You can search for one at vaccines.gov/find-vaccines (enter your ZIP code and check the box for “Flu Shot (65+, high-dose or adjuvanted).”
If you can’t find a place to get one of these three shots, don’t go without a flu shot this season altogether. The standard vaccine is still much better than nothing.
And how far you go to get a special shot may depend on just how how high your risk is of complications from the flu. Bartley notes that the extra boost to the immune system from one of these high-dose or adjuvanted vaccines is more important the more vulnerable you are to the flu. “If you’re an older adult who is frail or has COPD or other lung issues that would put you at high risk,” she says, “then I would drive that hour to get the better vaccine.”
More from Consumer Reports:
Top pick tires for 2016
Best used cars for $25,000 and less
7 best mattresses for couples
Consumer Reports is an independent, nonprofit organization that works side by side with consumers to create a fairer, safer, and healthier world. CR does not endorse products or services, and does not accept advertising. Copyright © 2022, Consumer Reports, Inc.
