Hog Cholera, a highly contagious disease of swine that formerly killed large numbers of hogs. The disease is caused by a virus. Hogs with acute cholera usually die quickly, those with the chronic form may live for weeks. Hog cholera is transmitted by infected feed contact with sick animals, birds carrying the virus from infected to clean areas, or careless handling of vaccines. Sick animals should be isolated. The disease was once a major cause of hog deaths in the United States but has been eliminated there by strict sanitation, the use of vaccines, and the slaughter of infected swine herds.