The Virus

African swine fever is a double-stranded DNA virus. It is robust and complex, and hardier than PED. The virus is stable over a wide range of temperatures and pH. It can survive putrefaction, meat maturing, cooking, smoking, curing, air drying, salting and freezing.

The virus is infectious for: 

  • 11 days in feces
  • Months in bone marrow
  • 15 weeks in chilled meat
  • More than 15 weeks in frozen meat
  • 3-6 months in cured hams that have not reached high-temperature cooking.

Transmission

The virus is transmitted from oral and nasal exposure and either through direct or indirect contact. Soft ticks and other stable flies can also move the disease.

  • Directly by contact of infected pigs with healthy pigs.
  • Indirectly by contact with the virus from excertions, secretions, and infected tissues; including the ingestion of contaminated pork or meat products, contaminated swill or kitchen waste, contaminated vectors such as feed, vehicles, and footwear.
Signs of ASF in Pigs
  • High fever
  • Weakness and difficulty standing
  • Vomiting and diarrhea
  • Red or blue blotches on the skin – particularly around the ears and snout
  • Coughing or labored breathing
  • In sow barns: miscarriage, abortions, stillbirths, and weak litters can occur
  • High proportions of the animals with the disease will die within 10 days

The incubation period of ASF is 5-15 days. There are both acute and chronic forms of ASF. Clinically the disease is characterized by hemorrhagic fever and multiple organ involvement.

If a pig survives the infection, they can shed the virus for up to six months.

If you suspect your pigs are infected with ASF, contact your licensed veterinarian. 

Diagnosis

The recognition and diagnosis of ASF can be difficult. Clinically, the disease looks identical to Classical Swine Fever, and looks very similar to Erysipelas, Salmonellosis, Septicemic Pasteurellosis, and other septicemic diseases.

Quick Facts
  • ASF is one of the most severe viral diseases for pigs of all ages.
  • Humans cannot catch ASF from infected pigs nor can they contract the disease from eating meat from a pig infected with ASF.
  • Domestic pigs, feral pigs, and European wild boar are equally susceptible to ASF.
  • To date, no cure or vaccine has been created.
  • ASF is recognized by the global veterinary society as one of the major threats to pig production, food security, and biodiversity in the world.
  • The disease can spread through direct or indirect contact and causes high morality.
  • The virus can persist for a long time in the environment, carcasses, and in a variety of swine products.