Flu Shot Facts, Part 2 of 5: The Four Flu Vaccines Recommended for Older Adults

This series breaks down "Flu Shots for Older Adults: What to Know & Do for 2026" by geriatrician Dr. Leslie Kernisan, MD MPH, of Better Health While Aging. The original article and its insights are hers; you can read the full piece here.

In Part 1, we covered why the flu is riskier after 65. Now for the practical part: which flu shot should an older adult get?

Dr. Kernisan's recommendation is clear: "if you are an older adult, I recommend getting one of the four flu vaccines specifically recommended for older adults."

Why older adults get "enhanced" flu vaccines

As Dr. Kernisan explains, aging immune systems make fewer antibodies in response to a standard vaccine. The enhanced vaccines are designed to make up for that in different ways: a higher dose, an added immune booster, a different manufacturing method, or new mRNA technology.

The four recommended vaccines

1. Fluzone High-Dose. Per the article, this vaccine "contains four times the amount of antigen, compared to Fluzone standard-dose" and is approved for adults 65 and older. More antigen gives the immune system more to respond to.

2. Fluad. Fluad "contains an 'adjuvant,' which is an additive meant to stimulate a better immune response," Dr. Kernisan writes. Think of the adjuvant as a helper that wakes up the immune system.

3. Flublok. Flublok is a "recombinant protein influenza vaccine," made without growing the virus in eggs, and it "contains three times the antigen dose compared with standard-dose inactivated flu vaccines."

4. mFLUSIVA (new for 2026). This is the newest option. According to Dr. Kernisan, mFLUSIVA "is an mRNA vaccine and it was approved in August 2026" for adults aged 50+. Its approval was "based on a phase 3 randomized trial that showed this vaccine was more effective than a standard-dose flu vaccine." One thing to know: she notes it "does tend to cause more fatigue and body aches after administration than other flu vaccines."

What if the pharmacy doesn't have these?

Don't skip the shot. Dr. Kernisan says plainly: "if none of these are available to you, it's fine to get a standard flu shot for adults." Some protection is far better than none.

Can you get a COVID shot at the same time?

Dr. Kernisan notes that if you are 65 or older, or otherwise at high risk, "you may be able to get your fall COVID vaccine at the same time." Ask your pharmacist or doctor.

Quick answers

What is the best flu shot for seniors in 2026? Dr. Kernisan recommends one of four: Fluzone High-Dose, Fluad, Flublok, or the new mRNA vaccine mFLUSIVA.

What is mFLUSIVA? An mRNA flu vaccine approved in August 2026 for adults 50+, shown in a phase 3 trial to be more effective than a standard-dose flu shot.

Is a regular flu shot OK if the senior versions aren't available? Yes. Per Dr. Kernisan, a standard adult flu shot is fine if none of the four are available.

From the Indigo team

A tip we often share with families: call the pharmacy ahead of time and ask which senior flu vaccines they have in stock. It saves a wasted trip, which matters a lot when a loved one has limited energy or mobility.

Coming up in Part 3 of 5: Is the flu shot safe? Dr. Kernisan tackles side effects and the most common myth: "the flu shot gave me the flu."

Source: Kernisan, Leslie, MD MPH. "Flu Shots for Older Adults: What to Know & Do for 2026." Better Health While Aging, September 18, 2026. https://betterhealthwhileaging.net/flu-shots-in-aging-what-to-know/

This post summarizes an article by Leslie Kernisan, MD MPH, for general education. It isn't medical advice. Talk with your or your loved one's doctor about which vaccine is right for you.