A viewer asks: “Source Creator, are viruses from animals a contagion for humans? If so, was the human body designed to handle an intruding virus, or is physical illness a natural part of the physical experience?”

There, indeed, are many viruses for which animals are susceptible, as well as humans, and so animals can be a vector for dissemination of a virus. You see this with rabies, for instance, where many animal species can become infected and, in turn, infect humans who handle them or are bitten. There are innate capabilities of the immune system that are designed to deal with foreign matter intruding within the body. This includes many kinds of objects but primarily microbes because they have the ability to multiply and the consequences of that multiplication can, in some cases, become dire, especially when there are toxic byproducts of that growth being released and threaten the host. This is a delicate matter and not a perfect system. Many times the workings of the immune system are more harmful than the organisms themselves would be, because in fighting off the microbes there is collateral damage to normal tissue to some degree because of the nature of the defensive strategies the immune system employs, using generation of highly reactive free radicals and enzymes, and so on, that can have some damaging effects on normal cells of the body when generated in high concentrations. So the immune system normally will recognize when a foreign organism is present and will seek to destroy it, and that is a protective mechanism that is natural and part of an innate immunity humans are designed to have for preservation.