Scientists injected mice with a mixture of immunostimulating molecules through their noses, which mimics the effect of some vaccines providing partial protection against several infectious diseases.[1] This cocktail protected mice against various respiratory pathogens, including SARS-CoV-2, for several months.[1] After exposure to a sublethal dose of SARS-CoV-2, control mice lost about 10% of their body weight within 3 days, while treated mice lost almost no weight.[1] Treated animals had less inflammation and lung damage.[1] The mixture was also effective against other mouse-infecting coronaviruses and two types of bacteria, including Staphylococcus aureus.[1] Unlike another 2023 mixture that only protected for a month, this approach provided protection for at least 3 months by activating both adaptive and innate immunity.[1] Researchers plan to test a version of this "universal vaccine" in humans.[1]