Giving Needle-Free Flu Vaccines a Shot

A utumn is here: Time to get a flu shot. But that seasonal jab in the arm may someday be history. Some less invasive immunization options are already available, and other developments now in clinical testing could make flu vaccines more effective and convenient. Vaccines for many infectious diseases confer long-term immunity with one shot or a series of injections, but researchers haven’t yet found a universal vaccine for the many viral strains that cause influenza. Instead, as flu viruses rapidly mutate, public health organizations decide each season which strains are likely to predominate. Producers then manufacture vaccines based on those guidelines. This means shots are only partially protective and must be administered every year. Some years the shot is more effective than others: In the 2014−15 season, people who received the shot were only 19% less likely to get sick than those who didn’t. By comparison, in 2010−11, the effectiveness was 60%, according to the U.S. Centers for Disease Control & Prevention (CDC). Although these vaccines are still crucial for preventing widespread illness and controlling outbreaks, clinicians and public health experts would like to have better tools to deliver vaccines and fight the influenza virus.