I do think that diseases can be transmitted from human to human, and that viruses, bacteria and fungi are part of that. Otherwise, it would not be possible to acquire so many many diseases. For example, if you put blood that has the HIV virus in a wound, that person would most certainly acquire the virus, the same with Hepatitis B, and so on. The same happens when you are close to someone that has flu. The chances of you getting flu are higher. I do believe in toxicity too, even in the spiritual or inner one, and that they can make your body more vulnerable before viruses and bacteria, and even to provoke some diseases, but I do think that bacteria and viruses have a role in producing diseases. They provoke them in animals, so why would not they provoke them in humans?