For years, researchers have been working on vaccines that aim to prevent viral infections by strengthening immune defenses at viruses’ doorway to the body: the nose. A small study recently published in PNAS presents a similar, if lower-tech, idea. Coating the inside of the nose with the over-the-counter antibiotic ointment Neosporin seems to trigger an immune response that may help the body repel respiratory viruses like those that cause COVID-19 and the flu, the study suggests. [time-brightcove not-tgx=”true”] The research raises the idea that Neosporin could serve as an “extra layer” of protection against respiratory illnesses, on top of existing tools like vaccines and masks, says study co-author Akiko Iwasaki, an immunobiologist at the Yale School of Medicine and one of the U.S.’ leading nasal vaccine researchers. The study builds upon some of Iwasaki’s prior research—which has shown that similar antibiotics can trigger potentially protective immune changes in the body—but it’s still preliminary, she cautions.