I doubt that there would be a mass extinction event for the GB. They would exercise basic precautions to prevent such thing, like eating separately, travelling on different planes etc. Their meetings are probably on zoom, rather than in person. In their position, a healthy level of paranoia is probably wise.
Edited: I know I cancelled out my first post in this thread, but there can be different approaches to the same problem. Making sure that everyone eats the same food may prevent one of them from poisoning the food supply. Eating separately ensures that at least some will survive an attempt.