In the eighteenth century, smallpox succeeded plague as the most feared disease. The two maladies, however, are very different. While plague is a bacterial disease, smallpox is viral. Plague is spread by rats and fleas, smallpox is transmitted by contact and airborne inhalation. Unlike plague, smallpox can exist as an endemic as well as an epidemic disease. The dread of smallpox was a result of its agonizing and unpleasant symptoms, which, in the case of survival, often left victims permanently disfigured. Prior to the discovery and successful implementation of inoculation and vaccination regimes, a host of ineffective and often dangerous treatments were attempted, including bleeding, purging, and cauterization of affected areas.