Flu Shot vs. COVID Booster vs. RSV Vaccine: Which Ones You Need This Winter, by Age Group

Every November, my clinic turns into a vaccine help desk. Patients walk in with the same three questions: "Do I really need the flu shot again?", "Is the COVID booster still a thing?", and "My pharmacist mentioned RSV. What is that, and is it for me?"

This year those questions are harder to answer than usual, and I do not blame anyone for being confused. The guidance coming from different health authorities does not line up neatly, the vaccine lineup has changed, and there is a brand-new type of flu shot on the shelf.

So I want to do what I do in the exam room: put the three vaccines side by side, explain what each one actually protects against, and then walk through who needs what, age group by age group. By the end, you should know exactly what to ask for at your next pharmacy or clinic visit.

Why This Season Feels So Confusing

Let me start with the elephant in the room.

In past years, the CDC released one clear set of recommendations every fall. That did not happen in the usual way this time. According to the AAMC, the CDC has not issued updated vaccine recommendations for the 2026-27 respiratory virus season, partly because its vaccine advisory committee (ACIP) has been tied up in litigation over its membership and childhood vaccine policy changes.

To fill that gap, major medical organizations stepped in. On September 2, four leading medical groups published independent guidance for the season, and all four agreed that everyone 6 months and older should get a flu shot. Their COVID and RSV advice varies by age and risk.

For the purposes of this guide, I lean on three sources: the CDC recommendations that are still in effect (flu and RSV), the joint guidance from groups like the American Academy of Family Physicians (AAFP), and the clinical data from last winter.

What Last Winter Taught Us

Before we compare vaccines, it helps to remember how rough last season was.

A study of the 2025-26 flu season published in JAMA Network Open estimated between 28 million and 49 million flu illnesses, 360,000 to 740,000 hospitalizations, and 22,000 to 74,000 deaths in the United States. The cumulative hospitalization rate was the third highest at that point in the season since 2010-11.

Much of that was driven by a drifted strain called H3N2 "subclade K," which did not match the vaccine perfectly. Even so, the shot still worked. CDC data showed that adults 18 to 64 who got a flu vaccine were 36% less likely to need a medical visit for flu and 29% less likely to be hospitalized.

A 29% drop in hospital risk might not sound dramatic. But consider this example from an earlier season: during 2022-23, when vaccine effectiveness was just 30%, flu vaccination was estimated to prevent 71,000 hospitalizations and 4,300 deaths. Modest protection, multiplied across millions of people, adds up to a lot of empty hospital beds.

Looking ahead, the CDC expects peak RSV hospitalizations this season to be similar to last season, within about 20%. In other words, we should plan for another busy winter.

Flu vs. COVID vs. RSV Vaccines at a Glance

Here is the head-to-head comparison I sketch for patients on the back of a visit summary.

Feature	Flu Shot	COVID-19 Vaccine	RSV Vaccine
Who it is for	Nearly everyone 6 months and older	Recommended for adults by major medical groups; federal guidance points to talking with your provider	Adults 75+, and adults 50 to 74 with certain health conditions
How often	Every year	Every year (two doses for 65+ per medical groups)	Once (not yearly, for now)
What it protects against	Influenza A (H1N1, H3N2) and B/Victoria	Updated COVID-19 variant	Respiratory syncytial virus
New this year	mRNA flu vaccine for adults 50+	Updated formula for 2026-27	No booster needed if you already had one
Common side effects	Sore arm, mild fatigue	Sore arm, fatigue, headache for a day or two	Sore arm, fatigue, muscle aches

Now let us go through each vaccine in more detail.

Vaccine #1: The Flu Shot

Who needs it: Almost everyone. The CDC recommends that most people age 6 months and older receive an annual flu vaccine.

What is in it: This season's shots are trivalent, meaning they target three strains. As ABC News summarized, the vaccine protects against influenza A(H1N1), influenza A(H3N2), and influenza B/Victoria.

What is new: For the first time, there is an mRNA flu vaccine. Johns Hopkins notes that a newly approved mRNA flu vaccine (mFLUSIVA) is available for adults age 50 and older. It uses the same platform as most COVID shots and is egg-free, which some patients with egg concerns appreciate.

As infectious disease expert Dr. William Schaffner told the AAMC, this year brings "a significant new entry" to the flu vaccine lineup.

If you are 65 or older: Ask for an enhanced vaccine. The CDC recommends higher-dose flu vaccines (including high-dose inactivated and recombinant vaccines) or adjuvanted inactivated flu vaccine for this age group, because our immune response naturally weakens with age. Per the AMA, the mRNA vaccine is also on the list of enhanced options for 65+.

My take: If you only get one vaccine this winter, make it this one. The data is the longest and most consistent of the three.

Vaccine #2: The COVID-19 Vaccine

This is where the guidance is most split, so I will be precise.

What federal guidance says: Federal recommendations have moved away from a broad "everyone should get it" message. As one summary put it, the CDC has pulled back from broad COVID-19 vaccination guidance, instead directing patients to consult their healthcare providers.

What major medical groups say: The joint guidance from medical societies recommends an annual updated COVID-19 vaccine for adults, and for adults 65+, a second dose 6 months later to boost protection.

Who I push hardest: In my own practice, the patients I most strongly encourage are:

Adults 65 and older
Anyone with a weakened immune system (cancer treatment, transplant, high-dose steroids)
People with chronic lung, heart, or kidney disease, or diabetes
Pregnant patients
Anyone who has never had a COVID vaccine

Practical tip: Because federal and medical-society recommendations differ, check your insurance coverage before you go. Most plans still cover it, but it is worth a 2-minute phone call or a look at your pharmacy app.

Vaccine #3: The RSV Vaccine

RSV (respiratory syncytial virus) is the one most of my patients know the least about, yet it sends a surprising number of older adults to the hospital. The CDC estimates between 15,000 and 20,000 RSV hospitalizations occur every year in U.S. adults aged 50 to 59 alone.

Who needs it: The CDC recommends a single dose of any FDA-licensed RSV vaccine for all adults ages 75 and older and adults ages 50-74 at increased risk of severe RSV.

What counts as "increased risk"? According to Immunize.org's summary of the ACIP list, high-risk conditions include:

Chronic heart disease (heart failure, coronary artery disease), but not high blood pressure alone
Chronic lung disease (COPD, emphysema, asthma)
End-stage kidney disease or dialysis
Diabetes with complications, or diabetes treated with insulin or an SGLT2 inhibitor
Severe obesity (BMI of 40 or higher)
Chronic liver disease such as cirrhosis
Living in a nursing home or long-term care facility

Immunize.org is clear that people age 50 through 74 who do not have a qualifying condition are not recommended to receive the RSV vaccine right now. They should wait until a high-risk condition develops or they turn 75.

How often: Just once, for now. As Dr. Schaffner put it, "The RSV vaccine continues to be a one-shot deal" for adults. Clinical trial data shows meaningful protection against severe RSV disease for at least 2 RSV seasons, and if you got one in 2023, 2024, or 2025, you do not need another this year.

During pregnancy: If you are between 32 and 36 weeks pregnant during RSV season, your obstetrician may recommend the RSV vaccine to pass along protection to your baby.

Which Vaccines Do I Need? An Age-by-Age Guide

Here is the simple breakdown I give patients. Remember, this is a general framework, and your own doctor may adjust it based on your history.

Ages 18 to 49 (generally healthy)

Flu shot: Yes, every year
COVID vaccine: Recommended by medical groups; talk it over with your provider
RSV vaccine: No, unless you are pregnant (32 to 36 weeks) during RSV season

Example: A 32-year-old teacher with no health problems should get a flu shot this week. Given that she spends all day in a classroom, I would also encourage the updated COVID vaccine.

Ages 18 to 49 (with chronic conditions or pregnant)

Flu shot: Yes, and do not skip it
COVID vaccine: Strongly encouraged
RSV vaccine: Only during pregnancy at 32 to 36 weeks, or in special cases your doctor identifies

Ages 50 to 64

Flu shot: Yes; the new mRNA option is available to you
COVID vaccine: Recommended by medical groups
RSV vaccine: Yes, if you have a high-risk condition from the list above

Example: A 58-year-old with COPD should get all three. A healthy 58-year-old runner needs the flu shot, should consider COVID, and can skip RSV for now.

Ages 65 to 74

Flu shot: Yes, and ask for a high-dose, adjuvanted, recombinant, or mRNA version
COVID vaccine: Yes, with a second dose about 6 months later per medical-group guidance
RSV vaccine: Yes, if you have a high-risk condition

Ages 75 and older

Flu shot: Yes, enhanced version
COVID vaccine: Yes, two doses spaced about 6 months apart
RSV vaccine: Yes, one dose, if you have never had it

Can You Get All Three on the Same Day?

Yes, in most cases. CDC guidance allows these vaccines to be given at the same visit, and healthcare providers should assess the potential risk of adverse events of each vaccine independently.

Here is how I advise patients to decide:

Do it all at once if: convenience matters, you might not come back, or you are 75+ and want protection in place before the holidays.
Space them out if: you had a strong reaction to a vaccine in the past, or you have an important event (a wedding, a big presentation) in the next 48 hours.

If you get more than one shot at a time, ask for them in different arms. You may feel more tired for a day, but you will be done for the season.

Is November Too Late?

Not at all. The CDC recommends getting vaccinated beginning in September through the end of October for the best protection. But flu season often peaks between December and February and can last into spring. A shot in November still gives your body about two weeks to build protection before Thanksgiving gatherings and holiday travel.

Remember, too, that the AAMC noted flu made an early appearance this year. If you have been putting it off, this week is a great time.

Three Myths I Hear Every Week

"The flu shot gave me the flu." It cannot. Injectable flu vaccines contain no live virus. What you might feel is your immune system responding: a sore arm, a low-grade fever, or fatigue for a day.

"I got the RSV shot last year, so I need it again." You do not. It is currently a one-time vaccine.

"Flu vaccines barely work, so why bother?" Even in a mismatched year like last season, the flu shot cut hospitalization risk by roughly a third in many groups. Vaccines also make severe illness less likely if you do get sick.

The Bottom Line

If you remember just three things from this guide, make it these:

Flu shot: Nearly everyone, every year. Seniors should ask for an enhanced version.
COVID vaccine: Recommended by major medical groups for adults, especially those 65+ and those with chronic conditions. Talk with your provider and check coverage.
RSV vaccine: One dose for everyone 75+, and for adults 50 to 74 with high-risk conditions. Not yearly.

Guidance may continue to shift this season, and I will update this post if it does. In the meantime, the best next step is simple: bring this list to your pharmacist or doctor and ask, "Based on my age and health, which of these do I need?"

Sources I Used

This article is for general education and is not a substitute for personal medical advice. Please talk with your doctor or pharmacist about which vaccines are right for you.