For the First Time, an mRNA Flu Shot Will Be Available to Some People in the United States. Here's What You Should Know

The Food and Drug Administration just approved the new type of flu vaccine for adults ages 50 and older. It relies on the same technology as many Covid-19 jabs. However, it’s unclear whether insurance companies will pay for the novel flu shot August 11, 2026 11:41 a.m. Older adults are especially at risk of flu-related complications. Jelena Stanojkovic via Getty Images The United States is finally getting a new type of flu shot. On August 5, the Food and Drug Administration (FDA) approved the mFlusiva vaccine for adults ages 50 and up. Made by biotechnology company Moderna, the novel jab relies on mRNA, or messenger RNA, technology—the same as many Covid-19 vaccines. Experts welcome the upgraded approach to help prevent the flu. The seasonal respiratory illness, caused by a virus, contributes to up to 710,000 hospitalizations and 52,000 deaths in the U.S. each year, according to estimates by the Centers for Disease Control and Prevention (CDC). “Having a flu vaccine that does not have to go through the archaic process of using chickens and eggs will benefit the public health enormously,” Georges C. Benjamin, CEO of the American Public Health Association, tells the New York Times’ Christina Jewett. “It will allow us to rapidly adjust to rapidly emerging new flu strains, a capacity we have not had before.” Here’s what you need to know about the new shot. What is an mRNA vaccine, and how is it different from a traditional flu shot? MRNA vaccines work by giving your body a set of genetic instructions in the form of mRNA. It tells your cells how to make a harmless piece of a virus, like a viral protein. As part of a normal immune response, your body will then create antibodies to fight off what it identifies as an invader. Then, the next time the antibodies run into that viral protein, they recognize and fight it off more quickly. Traditional vaccines get your body to recognize invaders in a different way. They include a killed, weakened or part of the virus itself to elicit an immune response. The viruses used are generally grown in chicken eggs, requiring a lengthy process. Near the beginning of each year, policymakers predict which flu strains will be circulating that fall and winter. “Typically, they need to start that production well before the fall to get the vaccine doses ready. If there’s a mismatch in strains, there’s really no way they can go back and update the vaccine and change it,” Hanover Matz, an immunologist at Washington University School of Medicine, tells Cassie Martin at Science News. “With an mRNA-based vaccine, you could feasibly cut down that production time to a couple of months.” How effective is the mRNA shot at preventing the flu, and are there side effects? The FDA’s approval is based on a late-stage clinical trial of nearly 41,000 people, which was published in May in the New England Journal of Medicine. Participants were ages 50 and older and spanned 11 countries. About half of them received Moderna’s new vaccine while the others received a traditional jab. Those who got the mRNA shot had 27 percent fewer flu cases than those who got the older type. “It also seems to generate a very strong immune response against the flu virus,” Matz tells Science News. In a study published in June in Nature Immunology that he co-authored, “people who received the mRNA-based vaccine had much higher levels of antibodies against flu one month after vaccination,” Matz says. “And those higher levels persisted for six months, which suggests that there is an increase in the duration of the protection.” The NEJM trial determined that the vaccine was safe, though it also found that side effects were more common among mRNA vaccine takers. They were mostly temporary, mild to moderate reactions, like pain at the injection site, fatigue and headache—which some people experience even with traditional jabs. However, some serious adverse Moderna vaccine-related events occurred, including a case of low blood pressure that led to a 3-day hospital stay and a case of heart inflammation. Did you know? Tough approval In February, Moderna announced that the FDA had refused to review its mRNA flu vaccine for approval. The federal move was deemed extremely unusual in the wake of the favorable NEJM trial. When can I get the new vaccine? Right now, the vaccine is authorized only for people ages 50 and up. Older individuals, especially those above age 64, are especially at risk of flu-related complications and make up most of the hospitalizations and deaths associated with the illness. MFlusiva will be available for this year’s flu season, according to a statement from Moderna, meaning it can be legally prescribed. Whether people will have access to it is a different question. Earlier this year, a federal judge blocked the CDC’s vaccine advisory committee from convening, and meetings have been canceled due to ongoing litigation. Insurance companies rely on the panel’s recommendations about who should get which immunizations, so without guidance, insurance probably won’t pay for the novel flu shot, Ofer Levy, director of the Precision Vaccines Program at Boston Children’s Hospital, tells Berkeley Lovelace Jr. at NBC News. Public distribution of the vaccine could also be limited without federal advice on who should receive the shots, he adds. “That is a serious concern.” You Might Also Like Get the latest stories in your inbox every weekday. More about: Aging Flu Health Medicine Microbes, Bacteria, Viruses Vaccines Viruses