What infectious diseases have nothing to do with threatening human health?

Infectious diseases that threaten human health do not exist. According to relevant public information, any infectious disease will affect human health. Even if some infectious diseases can only infect animals, their effects will eventually affect humans through the food chain. Infectious diseases that directly affect human health are: SARS, avian influenza, smallpox, leprosy, hepatitis A, mad cow disease, AIDS, rabies, cholera and so on.