African swine fever and swine fever are highly contagious and malignant pig diseases caused by viruses. The difference between two is that swine fever is caused by RNA viruses from the Flaviviridae family, while African swine fever is caused by DNA viruses that belong to the African swine fever virus family.
Pigs affected by the disease display a series of symptoms including high fever, purple spots on the skin, and bleeding of internal organs, especially lymph nodes, kidneys and intestinal mucosa. The course of the disease is divided into very acute, acute, subacute and chronic. Very acute: fever, sudden death, no other symptoms. Acute: high fever, remaining appetite, loss of appetite before death, rapid breathing, mental distress, cyanosis of limbs, ears, and skin, vomiting, diarrhea, and death, lasting 7 days. Subacute: fever, 3-4 weeks. Chronic: Symptoms are not obvious and last for several months. Currently there is no medication or vaccines to treat the illnesses.
The virus can exist for 100 days in refrigerated pork, 1,000 days in frozen pork, 1 month in pigsties, and 11 days in feces at room temperature. The disease is mainly transmitted through contact, specifically with food waste, arthropods, animal secretions or excretions, while being carried by vehicles and people. African swine fever is a Category A animal infectious disease in Taiwan and listed as a notifiable disease by the World Organization for Animal Health (WOAH). Although it causes acute and malignant infectious diseases in domestic pigs and wild boars, infecting pigs of all breeds and ages, it does not infect humans. Pigs that have passed slaughter and health inspection in Taiwan receive a label. When buying pork consumers should only choose products with a qualified mark to ensure it is safe to eat.