African swine fever: A burning threat to pig farmers

[ Dr Moloy Sarmah Baruah ]

African swine fever (ASF) is a disease of domestic and wild pigs of several regions around the world, caused by a highly environment resistant virus, African swine fever virus” (ASFV).

ASF was first detected in East Africa in the early 1900s, and later spread to Europe, and has recently been creating havoc in many Asian countries, including India. As per reports received till now, only domestic pigs and wild boars are susceptible to the virus. The soft ticks belonging to the Ornithodoros genus also may act as biological reservoirs and vectors.

As there is no effective vaccine and treatment till now, the mortality rate of pigs can reach upto 95 percent to 100 percent. This deadly virus can survive on clothes, boots, wheels and other materials. Therefore, if adequate measures on human/animal movement are not taken, the disease may spread from one place to other.

Though till now there is no report that it can affect human health, its detrimental impacts on pig health and welfare leads to devastating effects on pig populations and the farming community. The virus can also survive in various pork products, such as ham, sausages or bacon. Therefore, unhygienic handling of those products may also spread the disease from one place to other.

Transmission can also occur via contact with pig faeces, bodily fluids, or contaminated carcasses of infected pigs, as well as when pigs eat pork products that contain the ASF virus. Based on the disease causing power of the virus and the immune status of the infected pigs, symptom wise the disease appears in the form of acute to chronic. In acute disease, pigs usually show symptoms of high fever, followed by loss of appetite, depression, haemorrhage that causes blackening of the skin, and coughing. Pigs used to die within four to 20 days. In chronic disease, the symptoms may vary from reduced growth, skin lesions, swelling and secondary infections with a mortality rate of 30 to 70 percent.

Advice for farmers:

At the farm level, the following key biosecurity principles should be implemented to keep animals healthy and away from the diseases.

  1. If you give kitchen waste to your pigs, boil if for minimum 30 minutes.
  2. Do not allow any visitor to enter your pig farm.
  3. Clean and disinfect the pig farm premises and equipment used in your pig farm with appropriate disinfectant.
  4. Regular monitoring of pigs is of utmost important, and if any sign of disease appears, report to the nearby veterinarian immediately.
  5. As far as possible, at present do not add new pigs to your farm. If at all needed to introduce new pigs to your farm, then isolate them for 30 days and observe them minutely for their health status and any clinical sings.

Other general sanitary measures that may be implemented include early detection and human killing of animals (with proper disposal of carcasses and waste) as per the advice of veterinarian and local authorities; thorough cleansing and disinfection, pig movement control, surveillance and detailed epidemiological investigation; strict biosecurity measures on farms, and a good coordination among the veterinary services and wildlife & forestry authorities for successfully prevention and control of ASF. (The writer is Head, KVK, Leparada district)