How to Prepare for the 2026 Flu Season

4 min readScientists tracking flu strains in the Southern hemisphere predict influenza A(H3N2) subclade K variant AKA “Super-K” will be the culprit behind a majority of US flu cases this fall and winter.The updated flu vaccines will target three flu virus strains, including “Super K.”The FDA released a new flu vaccine for adults over 50 that is made from the same mRNA technology in COVID vaccines.Clinical trial data showed the new flu shot better protected older adults from the flu compared to a standard flu shot. However, there is a greater risk for temporary mild to moderate side effects such as injection site pain and headaches.WHILE YOU’VE BEEN squeezing in some last-minute summer fun, the flu virus has been quietly simmering in the background. Flu cases pop up here and there during the warmer months, before really taking off in the fall.A lot has changed with the flu virus since last year (as a reminder: a sudden, new variation made the flu shot a poor match for circulating strains). The result was a brutal holiday season, from a viral illness perspective, making plenty of people wary of what’s ahead.This year, though, there is good news. Scientists have designed an additional flu shot made for older adults that works differently from traditional vaccines. The goal is to create better protections for the people most vulnerable to severe symptoms and flu-related hospitalizations.“There are a lot of choices out there,” says Jo-Anne Passalacqua, MD, infectious disease specialist at Hartford HealthCare's St. Vincent's Medical Center. “Choices are great, but sometimes that leads to confusion on the part of the public.”Below, doctors break down exactly what you need to know for this upcoming flu season and the best way to protect yourself.Which Flu Strain Will Hit the US This Fall?THIS YEAR, THE majority of flu cases in Australia this year were from the influenza A(H3N2) subclade K variant. You may have also heard this as “Super-K.”Scientists in the US have an idea which flu strains will dominate the country based on what happens in the Southern Hemisphere. Typically, that means analyzing Australia’s flu data to try to forecast what could happen with our flu season, says John Sellick, DO, an infectious disease expert and professor of medicine at the University at Buffalo. (Australia’s flu season takes place during our summer.)Is the US Better Prepared Than Last Year?DOCTORS ARE HOPEFUL this year won’t lead to outbreaks like last year. With that said, no one truly knows how effective a vaccine is until after people get it.“We would like for the vaccine to be better but some years it’s less than perfect,” says Richard Ricciardi, PhD, executive director in the Center for Health Policy and Media Engagement at George Washington University School of Nursing. “That doesn’t mean it’s useless or not valuable—it still reduces hospitalizations and deaths.”Last year’s flu vaccine was a mismatch for the flu strains that ended up circulating across the US. As a result, CDC estimates found the shot was 36 percent effective at reducing outpatient medical visits. Vaccine effectiveness in the past 15 years has typically ranged between 30 to 60 percent. (The 2014 to 2015 flu season was an outlier at 19 percent).The current flu shots will target three strains: H1N1, B/Victoria lineage, and H3N2. “This year’s flu vaccine has been updated to take into account the H3N2 subclade K,” Dr. Passalacqua says. “But we never know if it’s a good match until the flu arrives and we begin analyzing cases.”Any New Symptoms to Watch Out for This Flu Season?DOCTORS SAY YOU can probably expect more of the same flu symptoms. “I’ve been through many flu seasons, and the symptoms are fairly parallel from one season to another,” says Ricciardi. People with the flu likely start off with a sudden fever and chills, followed by a cough, muscle aches, headache, and fatigue.“The flu is a whole body illness—not just a stuffy nose or coughing,” says Dr. Passalacqua.So I Heard About A New Design for Flu Shots?THE GENERAL PUBLIC will have the usual access to flu vaccines that roll out at your local pharmacy. But this year older adults have an extra option. Earlier this year, the FDA approved a new flu vaccine called mFLUSIVA for adults 50 years and over. This new flu shot is made with the same mRNA technology as many COVID vaccines.“Rather than having to make a decision six months in advance on what strains to include, you can probably decide four to six weeks ahead of time for this vaccine because of how they’re manufactured,” Dr. Sellick says. “That would give you more time to decide what you want to put in and hopefully make it a better match.”A phase 3 clinical trial tested the effectiveness of the mFLUSIVA vaccine compared with a standard vaccine. Of the 20,179 people injected with the new shot, only 411 developed a lab-confirmed case of the flu (2 percent). Meanwhile, 557 of 20,124 recipients of the standard vaccine got sick with the flu (2.8 percent).There are some caveats, however. The trial also found more severe side effects with this new flu vaccine vs. a standard vaccine. For example, people were more likely to experience injection site pain, fatigue, headaches, and muscle weakness. It’s also not clear yet if this vaccine will lower the risk of being hospitalized if you get the flu, though.What’s With the Age Cutoff?DR. SELLICK SAYS the new flu vaccine is targeted for older adults because they are the most vulnerable to the worst of flu infections. “We tend to develop less of an immune response in the nose as we get older, which means the nasal spray vaccine doesn’t work as well in older groups,” he says.Again, you still have your choice of more traditional flu shots, including egg-based vaccines, cell-based vaccines, and recombinant vaccines. The nasal flu vaccine, aka FluMist, is also an option for healthy people ages 2 through 49.If you have questions about the upcoming flu season or flu vaccines, doctors say the best source is always your health care provider. “I always point out to people that getting vaccinated results in less severe illness, less risk of coming into a hospital, and less risk of people dying,” Dr. Passalacqua says. “Despite a lot of concern that occurred during the COVID pandemic around vaccination, these vaccines are saving lives.”Korin Miller is a seasoned freelance writer specializing in general wellness, sexual health and relationships, and lifestyle trends, with work appearing in Men’s Health, Women’s Health, Everyday Health, Food & Wine, and more. She has a master’s degree from American University and lives by the beach.