African Swine Fever Awareness
By Dr Marthie Kleynhans
African Swine Fever is a very contagious, haemorrhagic (bleeding) disease of pigs that is caused by the African Swine Fever (ASF) virus. This disease can spread rapidly through herds and can be fatal. Outbreaks of this disease can be devastating to a country’s economy as all the pigs that show clinical signs or those that were in contact with infected pigs should be slaughtered.
How can your pigs get infected with the African Swine Fever virus
The cycle of the virus is quite complex as the natural cycle is between warthogs and a soft tick vector (O. moubata). These ticks live in the burrows of the warthogs, thus it makes eradicating or controlling them very difficult.
Pigs can get infected with the virus either by a bite from these ticks or by ingesting warthog meat. Infected ticks can also transmit the virus to healthy pigs through blood contact or by ingesting waste food containing pig meat or pig products.
Infected pigs can shed the virus for up to 2 months after they were infected. Those pigs that survive the infection can become persistently infected, but they do not excrete the virus or transmit it to their offspring.
What are the signs to look out for?
One of the most important clinical signs to look out for is redness of the skin, ears, tummy and legs with blood sometimes coming out of the rectum and nose. Abortions are also one of the first signs during an outbreak. Other signs to look out for are loss of appetite, respiratory distress, vomiting, diarrhoea and a very high fever.
What should you do when you think your pigs have ASF?
Inform your veterinarian or animal health technician immediately. This is a controlled disease and it must be reported to the state. It is very important that the correct people should be informed as this disease can be detrimental to the economy if it starts to spread between herds. The quicker we can control and contain the disease, the less chance for it to spread and fewer pigs would die.
How can one control or prevent the disease?
Unfortunately, there is no treatment for ASF and there is also no vaccine developed yet. The only way you can prevent the disease is to ensure that neither infected live pigs or pig products are introduced to herds free of ASF. One should also try to keep your pigs away from warthogs. If you would like to move your pigs or any pig products, you must inform your State Veterinarian so that he or she can issue a movement permit to you. You need a movement permit even if you just want to transport your pigs to the abattoir.
What are the minimum standards for piggeries?
Your pigs should be properly fenced, with at least a 1.8m high perimeter fence. The bottom of the fence should be covered with 60cm of diamond mesh and must go 150mm into the ground.
It is also important that you should not feed swill, especially containing venison or pork products, even if it is cooked animal or vegetable products.
What will happen if your pigs are diagnosed with ASF?
As mentioned, there is no treatment for this disease. The only way to get your herd and farm free from ASF is to implement an eradication program which involves rapid diagnosis, slaughter out of all animals and proper disposal of the carcasses. Your farm will be placed under quarantine until all infected animals are disposed of. No animals (including pigs and all other species) may be moved onto or off the land that is quarantined. Sanitary measures should also be applied and there should be proper control of the movement and treatment of waste food.
