What is the difference between the regular flu shot and the senior flu shot

With age comes a great many things: wisdom, maturity, beauty… And also a weaker immune system! This places adults over the age of 65 at greater risk for severe complications from influenza (flu).

Prevention is an important step to keeping healthy this flu season, and getting a flu vaccine is crucial. A quadrivalent flu vaccine is designed to protect against four different flu viruses, including two influenza A viruses and two influenza B viruses.

Flu Season

In the US, flu activity peaks in January and February, but can begin as early as October and continue as late as May. Vaccines take 2 weeks to build immunity in the body.

Safety

Flu vaccines are safe. Vaccine viruses used are inactivated (“killed”) or weakened and CANNOT cause influenza.

Effectiveness

60% less likely to need treatment for flu after get vaccination. Also reduces other illnesses, antibiotic use, time off work, hospitalizations, and deaths.

NOTE: Public Health experts have not recommended one type of flu vaccine more highly than another for people 65 and older. They advise getting any type of flu vaccination as the first and most important step in protecting against the flu.

As you age, your immune system gets tired — but an extra-potent flu vaccine can wake it up.Luis Alvarez/Getty Images

The flu vaccine is the best way to protect against the flu, which is why the Centers for Disease Control and Prevention (CDC) recommends that everyone 6 months of age and older (with rare exceptions) get a flu shot every year.

U.S. health experts anticipate a challenging flu season ahead now that mask mandates and other COVID-19 protections — measures that had the added benefit of driving down flu rates to historic lows — have largely disappeared. The right flu vaccine can help keep you from getting infected or experiencing potentially serious complications.

If you’re an older adult, this annual flu shot is especially important. In past flu seasons, 70 to 85 percent of flu-related deaths and 50 to 70 percent of flu-related hospitalizations occurred in people age 65 years and older.

The U.S. Food and Drug Administration (FDA) has approved two flu-vaccine types specifically for people 65 and up: higher-dose vaccines and adjuvanted (amped-up) standard-dose vaccines. But in years past the CDC did not suggest that seniors opt for one of those vaccines; instead, the agency recommended any licensed, age-appropriate flu vaccine, with no preference for one kind over any other.

The CDC changed its position earlier this year. It now recommends that, when possible, seniors choose a higher-dose flu vaccine (Fluzone High-Dose or the egg-free Flublok recombinant) or an adjuvanted standard-dose flu vaccine (Fluad) over other types. If these vaccines aren’t available, the CDC recommends getting a regular standard-dose vaccine.

“Given their increased risk of flu-associated severe illness, hospitalization, and death, it’s important to use these potentially more effective vaccines in people 65 years and older,” said José R. Romero, MD, the director of the CDC’s National Center for Immunization and Respiratory Diseases, in a statement.

He added that the new CDC recommendations are especially noteworthy for Black, Latino, and Asian seniors, who researchers have found are less likely than white seniors to get these extra-protective vaccines.

Read on to learn more about the ideal flu vaccines for people 65 and older, including when to get the shot and what side effects to expect.

What Do People 65 and Over Need to Know About the Flu Shot?

Adults 65 and up may not mount as strong an immune response to a standard flu vaccine as younger people, which is why they should seek out a high-potency shot. Purvi S. Parikh, MD, of NYU Langone Health explains.

1. The 65-and-Up Flu Shots Can ‘Wake Up’ a ‘Tired’ Immune System

As is true with all vaccines, standard-dose flu vaccines become less effective the older you get, according to Gregory Poland, MD, an internal medicine doctor at the Mayo Clinic in Rochester, Minnesota. “The immune system gets ‘tired,’ so to speak — that’s called immunosenescence,” says Dr. Poland.

Higher-dose or adjuvanted standard-dose vaccines are designed to stimulate the flagging immune systems of older adults. Compared with standard-dose (inactivated) flu vaccines, higher-dose flu shots contain four times the amount of antigen — the part of the vaccine that stimulates the immune system to produce protective antibodies.

2. The 65-and-Up Flu Shots Can Stave Off Infection, Serious Illness, and Death

Every flu season is different, so predicting the efficacy of any flu shot in a given year is difficult. Still, studies have shown that in seniors, the higher-dose and adjuvanted standard-dose flu vaccines can prevent more infections and save lives compared with standard-dose flu shots, says Paul Auwaerter, MD, the clinical director of the division of infectious diseases at Johns Hopkins Medicine in Baltimore.

The data is best for the higher-dose vaccine, which in one study showed itself to be 24 percent better at preventing the flu in people 65 and older than the standard-dose vaccine, says Poland.

The higher-dose vaccine also appears to be more effective than the standard-dose vaccine at keeping people who do get the flu out of the hospital. In a study conducted during the 2013–14 flu season of more than 38,000 residents in 823 nursing homes in 38 states, people 65 and older who got the Fluzone High-Dose vaccine had a lower risk of hospital admission than people in that age group who got the Fluzone standard dose; this was especially true for residents of long-term care facilities.

“Both those studies were done with what’s called a trivalent vaccine — it covered two A strains and one B strain [of the influenza virus],” says Dr. Auwaerter. The higher-dose vaccine for the 2022–23 flu season will be quadrivalent, covering four flu strains, 2A and 2B, he explains. There will be no trivalent vaccine available for the upcoming flu season, per the CDC.

A study published in July 2020 in the Journal of Infectious Diseases found that both the Fluzone High-Dose and Fluad (adjuvanted standard-dose) vaccines performed about the same in preventing the flu and flu-related hospitalizations among older adults.

7 Flu Shot Myths You Should Stop Believing

No, the flu shot can’t give you the flu. Here’s a look at the (many!) misconceptions people have about the flu vaccine.

3. The 65-and-Up Flu Shots Are Safe and Have Only Mild Side Effects, if Any

Seniors who get the higher-dose or adjuvanted standard-dose flu shots are more likely to report side effects than people who get the standard dose. Still, most people had either no side effects or mild ones that included pain or redness at the injection site, headache, muscle aches, and malaise (feeling blah).

Poland reports that he has received both the standard-dose flu shot and the higher-dose shot. Based on his experience, he doesn’t think that most people will register much of a difference when it comes to side effects.

He notes that it’s safe to get the COVID-19 vaccine or booster at the same time as any type of flu shot, including the higher-dose flu shot.

Some research published in JAMA Network Open in July of this year suggests you’re more likely to have (generally mild) side effects if you get a COVID-19 booster and a flu shot simultaneously, so if that’s a concern, you may opt to space them out a bit.

4. The 65-and-Up Flu Shots Have a Track Record — and Are Covered by Medicare

Even though the CDC is just now recommending the 65-and-up flu shots over the standard-dose flu shots, these vaccines aren’t a new thing: They've been around for years, says Poland.

If you are hearing about the higher-dose shot for the first time from your pharmacist or healthcare provider, it may be simply because this is the first year that the CDC is preferentially recommending it, along with the other vaccines designed for people 65 and older.

“That’s because they have determined that the efficacy is superior, and there’s a good enough supply to recommend it,” says Poland. These types of vaccines are a little pricier than standard-dose vaccines, although Medicare will cover the cost for enrollees, he says.

Bottom Line: Any Flu Vaccine You’re Eligible for Is Better Than No Vaccine 

“If you list them in order of preference, my first choice would be to get the high-dose vaccine; the next would be the recombinant or adjuvanted vaccine, and the last choice would be to get the standard dose vaccine — but remember, something is better than nothing,” Poland says.

That’s also what the CDC advises: If you’re 65 or older and can’t find a place that administers higher-dose flu shots or adjuvanted standard-dose shots, go ahead and get the regular standard-dose vaccine.

A flu shot has benefits even beyond lowering your risk of hospitalization or death as a result of the flu. For instance, “In people 65 or older, the benefit of getting the flu vaccine in preventing a heart attack is equal to taking a daily aspirin, taking a beta-blocker, or stopping smoking,” says Poland.

Get the High-Dose Flu Shot in September or October

You can get the flu shot anytime flu viruses are circulating, but timing your shot well will give you the maximum level of protection at the peak of flu season, which is typically between December and February. Keep in mind it takes about two weeks after vaccination for antibodies to develop and provide protection.

Because immunity may decrease more quickly in older people, it is especially important that people 65 and older not get vaccinated too early. September and October are generally good times, per the CDC. If you miss that window, it still makes sense to get vaccinated.

If you want to increase your chance of getting a flu shot designed for people 65 and up, call your primary care provider, local health department, or pharmacy before scheduling your appointment.

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