This. Is. FASCINATING: “The vaccine, which contains dead versions of the bacterium Paenibacillus larvae, comes in the form of food. The vaccine is incorporated into royal jelly, a sugar feed given to queen bees. Once they ingest it, the vaccine is then deposited in their ovaries, giving developing larvae immunity as they hatch.” https://www.nytimes.com/2023/01/07/science/honeybee-vaccine.html?smid=nytcore-ios-share&referringSource=articleShare
U.S.D.A. Approves First Vaccine for Honeybees

Dalan Animal Health’s vaccine for American foulbrood, an aggressive bacterial disease, is the first for any insect in the United States.

The New York Times

@lussenpop

This is amazing, because for now controlling foulbrood is done by burning all the affected beehives.