Your next vaccine may not come in a syringe—it might arrive on a piece of dental floss.⁠ ⁠ In a groundbreaking study, scientists demonstrated that coating dental floss with inactivated virus particles and applying it along the gumline can trigger a powerful immune response. Targeting the junctional epithelium—a thin, leaky layer of tissue where gums meet teeth—researchers vaccinated lab mice against the flu. The flossing technique offered full protection from infection, activating antibodies not just in the bloodstream but also in mucosal surfaces like the lungs, nose, saliva, and even feces.⁠ ⁠ That dual response is critical. Mucosal surfaces are where most pathogens enter the body, yet traditional injected vaccines rarely reach them. In contrast, this floss-based method stimulated robust immunity across both systemic and mucosal tissues, offering layered protection. The mice showed elevated T cells, stronger lymph nodes, and antibody-producing cells in their spleens and bone marrow, ...