Red-necked keelback snakes possess a potent toxin derived from the toads they consume, which can cause severe harm to predators like mongooses. The snakes store these toxins in specialized nuchal glands.
Bats carry a lot of very deadly pathogens like Ebola virus, Nipah, Hendra, coronavirus, and also rabies virus. People are finding more and more bat-borne viruses. When such viruses are transmitted to humans, the results are often fatal so there's a lot of interest in trying to prevent spillover in the first place.
Last November, the UK government announced a bold plan to phase out animal testing in some areas of research. Animal tests for skin irritation are scheduled for elimination this year, and some studies on dogs should be slashed by 2030. The long-term vision is 'a world where the use of animals in science is eliminated in all but exceptional circumstances'.
In a study published in Science Advances, researchers in China fed Aedes aegypti mosquitoes blood that contained either a vaccine against Nipah virus or the rabies virus. The viruses, contained in the vaccines, replicated inside the insects and reached their salivary glands, allowing them to pass on the vaccine when feeding on bats or when the bats ate the insects.