Research in honeybees has shown that vitellogenin, a protein, can carry immune signals from queens to their offspring. This could be used to boost immunity in bees to bacterial and viral pathogens. Although it will require more research and testing, a vaccine based on this approach may help with management of colony collapse disorder in commercial hives.
Read more about the prospects for a commercial honeybee vaccine in the New York Times.
The original research study on honeybee immunity is available in PLOS Pathogens.