Edward Jenner asserted that modern diseases arose from a closeness to animals that was not intended by nature. Jenner became famous for his successful method of preventing smallpox. The original "vaccine" was named after the cow from which it came. But despite the success of Jenner's method, many of his critics were concerned about the mid- and long-term effects of vaccination: they feared that to be vaccinated was to become animal. Even worse, this communion with beastly matter was seen as a kind of degenerate lust, a form of bestiality and monstrous reproduction, which would bring forth a "modern chimera." For some, cowpox vaccination was a sordid and unholy communion, the embodiment of an immoral trinity of animality, bestiality, and sexually transmitted disease.