hog cholera, acute, highly infectious viral disease of swine, also called swine fever. It is perhaps the most serious disease of swine in North America. It is characterized by dullness and listlessness, loss of appetite, rise in temperature to between 105°F (41°C) and 107°F (42°C), diarrhea, and often death. Purple hemorrhagic areas will appear on the abdomen and many pigs display nervous signs, such as circling, incoordination, muscle tremors, and convulsions. Mortality is very high and recovered animals are permanently stunted. The disease is transmitted readily by direct or indirect contact. The virus may enter a herd through contaminated feed, water, equipment, or by contact with an infected animal or person. At one time, feeding pigs raw garbage containing pork scraps from infected pigs was a common cause of infection. For this reason the United States and many other countries now prohibit the feeding of uncooked garbage to pigs. A national hog cholera eradication program has been established in the United States to eliminate all possible sources of virus introduction. A vaccine is available in areas where the disease is still present.