NEWS Health News A Universal Flu Vaccine Is in the Works, and Could Replace Your Annual Flu Shot By Claire Bugos Claire Bugos Twitter Claire Bugos is a staff reporter covering health and science for Verywell. Learn about our editorial process Updated on December 16, 2020 Fact checked by Marley Hall Fact checked by Marley Hall LinkedIn Marley Hall is a writer and fact checker who is certified in clinical and translational research. Her work has been published in medical journals in the field of surgery, and she has received numerous awards for publication in education. Learn about our editorial process Share Tweet Email Print ~User7565abab_575 / Getty Images Key Takeaways A universal flu vaccine could be effective in protecting against any strain of the influenza virus, potentially replacing the annual flu shot.One vaccine candidate has passed its first test in a small clinical trial.The vaccine targets the stem of the virus’s surface protein to recognize the virus, regardless of its mutations. Each year, people around the world receive a new influenza vaccine—also known as your annual flu shot. Because the flu—one of the most wide-spread viruses—mutates so quickly, scientists must revamp the vaccine each year to account for new strains that arise. Now, scientists are working to develop a universal flu vaccine that could protect the body against diverse influenza strains and subtypes for years, doing away with the annual flu shot. In a study published last week in the journal Nature Medicine, researchers announced promising results from a phase I clinical trial of the vaccine. Older Adults Vulnerable to 'Twindemic' of Flu and COVID-19 In this clinical trial, researchers from Mount Sinai studied the vaccine’s safety and ability to provoke an immune response to the vaccine. A study of 65 trial participants in the U.S. ages 18 to 39 indicated that the vaccine “induced a broad, strong, durable and functional immune response,” which endured for at least 18 months, according to the study’s authors. The authors state that this vaccine could provide long-term protection after only two or three doses. How Can You Prevent Flu During COVID-19? 6 Doctors Offer Advice “In terms of a universal flu vaccine’s impact on public health in the United States, it could reduce flu-associated morbidity and mortality for both seasonal and pandemic influenza,” Vivien Dugan, PhD, MS, deputy director of the Centers for Disease Control and Prevention (CDC) Influenza Division, tells Verywell in an email. What This Means For You A universal flu vaccine could provide protection against any strain of the influenza virus, rendering it unnecessary for people to receive a new shot each year. However, scientists say an effective vaccine could take years to develop. How the Universal Vaccine Works Each year, the influenza virus mutates and “reassorts” genes between strains. When it mutates, the body’s immune response may not recognize the new variation of the virus, causing some strains to avoid both natural and vaccine-induced immunity. Scientists develop new vaccines every year to account for such mutations. The vaccine protects against the three to four strains they predict will be most common in the coming year. It typically contains a mix of weakened or inactivated viruses with a mix of hemagglutinins (HAs)—the proteins that cover the surface of the influenza virus. How to Safely Get a Flu Shot During the COVID-19 Pandemic The typical flu shot attempts to build an antibody response to the head of the HAs. There is a small part of the head that mutates frequently so that the antibodies are unable to recognize and defend against the virus. This new vaccine incites antibodies to target the stalk of the surface protein, rather than the head. The stalk is much less prone to mutation and stays structurally the same in each variation of the influenza virus. However, the body’s immune responses are trained to respond strongly to the HA’s head, overriding antibody production for the stalk. To get around this, the Mount Sinai team created what they call the chimeric HAs vaccine. These have the same stalks but unfamiliar heads, which trigger a much lower antibody response to the head and a higher response to the stalk. “The beauty part of this vaccine is that it’s not only broad, but multifunctional with stalk-specific antibodies that can neutralize many kinds of influenza viruses,” Adolfo García-Sastre, PhD, co-author of the study and director of the Global Health and Emerging Pathogens Institute at the Icahn School of Medicine at Mount Sinai, said in a press statement. Coronavirus News With a chimeric HA-based vaccine, people may have long-term immunity to many variants of influenza after two to three shots, the authors say. This could be helpful for public health efforts to increase immunity across a population. “This universal vaccine could be particularly beneficial to low- and middle-income countries that don’t have the resources or the logistics to vaccinate their populations each year against influenza,” García-Sastre said. Implications of a Universal Vaccine The typical influenza shot includes three to four strains of the virus which scientists think are most likely to circulate in the coming year. Through a global network of health centers, scientists gather data on which strains of the virus are most prevalent during the flu seasons in each region, in order to predict which strains will most likely circulate worldwide the following year. Because it can take six months to develop a flu shot, the strains included in the vaccine may not match those that are actually circulating when flu season starts. Flu Cases in the U.S. Are Low—Will It Last? A universal flu shot could provide effective protection against an array of influenza strains. The ability to vaccinate many people with a universal flu shot could minimize the effect of a pandemic virus. As seen in the H1N1 outbreak in 2009, these viruses can emerge unexpectedly. When this happens, scientists need to generate new vaccines to match the pandemic strain—a process that can take six months. “An influenza virus vaccine that results in broad immunity would likely protect against any emerging influenza virus subtype or strain and would significantly enhance our pandemic preparedness, avoiding future problems with influenza pandemics as we see them now with COVID-19,” Florian Krammer, PhD, professor of microbiology at the Icahn School of Medicine at Mount Sinai, and co-author of the study said in the statement. Updating the Vaccine The Mount Sinai study is one of several stalk-based universal flu vaccine candidates. “Developing a universal flu vaccine poses an enormous scientific and programmatic challenge, but a number of government agencies and private companies already have begun work to advance development of a universal flu vaccine,” Dugan says. Part of what makes the process so challenging, she says, is that each person who receives a vaccine is different. Different factors can come into play when determining the benefits someone might receive from the vaccine, including: A person’s ageUnderlying medical conditionsHistory of prior infectionsPrior vaccinations The U.S. Department of Health and Human Services is working toward the long-term goal of creating a universal flu shot in collaboration with the CDC and other agencies. What Is the Difference Between a Flu Epidemic and a Flu Pandemic? “Efforts, resources, and advanced technologies allocated to the rapid development of safe COVID-19 pandemic vaccines may be broadly applicable to future influenza vaccine development, including approaches towards a universal influenza vaccine,” Dugan says. “This is something that CDC, federal partners, industry, and other domestic and international public health partners are exploring.” 2 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Nachbagauer R, Feser J, Naficy A. et al. A chimeric hemagglutinin-based universal influenza virus vaccine approach induces broad and long-lasting immunity in a randomized, placebo-controlled phase I trial. Nat Med. 2020. doi:10.1038/s41591-020-1118-7 Mount Sinai. Mount Sinai Researchers Advance a Universal Influenza Virus Vaccine. December 7, 2020. By Claire Bugos Claire Bugos is a health and science reporter and writer and a 2020 National Association of Science Writers travel fellow. See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit