Farmers in Murang'a county have lost over 3,000 pigs in the last two months to a viral disease known as African swine fever, even as researchers step up interventions to contain a disease that has wiped away farmers' fortunes since it was first detected in the country in 1921.
The over 200 farmers say they have witnessed a systemic trend in the death of their pigs since May this year. One farmer lost 20 of his pigs in a week. “And the sad thing is that we dont know what to do because even government seem to have resigned to this fate,”said Nathaniel Waiguru a pig farmer in Kandara who lost 20 of his pigs.
According to veterinarians the disease which can occur in chronic, sub-acute or acute form is transmitted through direct contact with infected pigs, faeces or body fluids, indirect contact with equipment, vehicles or people who work with pigs between pig farms with ineffective biosecurity, pigs eating infected pig meat or meat products or biological vectors like ticks.
“While early detection may assist the animal health officers save the pigs, most of the times the farmers diagnose the disease when its already too late since they majority dont do thorough and daily monitoring of the pigsties,”said Dr.Mercy Kinyua a veterinarian in Murang'a. The disease take between five and fifteen days to manifest itself with the striking symptoms being diarrhoea, vomiting,weakness and unwillingness to stand, and abortion and still births.
Farmers in Murang'a say most of the signs they had spotted before calling clinical officers were some listed above. And although the disease cannot be passed on to humans, the officers are sounding the alarm on the way the dead pigs are disposed. When the pigs started dying, the farmers decided to slaughter them, threw away the liver and pancrease which had red scars and were larger than normal then sold the rest of the meat to butcheries in the area and other towns including Nairobi.
“That is very dangerous and although the disease cannot be passed to humans, these people are risking their lives and that of others with other potential diseases,”said Dr Kinyua.
So why is the disease so prevalent in Afria? According to Food and Agriculture Organization, extremely rapid spread of the fever is due to its highly contagious nature and the ability of the virus to persist in a protein environment, including meat products, for long periods.
Since no vaccine exist at the moment, the only means of control is by compulsory slaughter, avoidance of which leads to clandestine movement of potentially infected pigs. The most important factor that has been identified as contributing to the spread of this devastating disease is lack of early detection due to insufficient knowledge on the part of farmers and pig breeders and among technical personnel regarding the manifestation of the disease.
But there is a ray of hope. Scientists at the International Livestock Research have launched research of a vaccine to be used against the fever. The study which is still at an early stage is trying to identify antigens and best-bet delivery systems to be used.
“Research in this area, with the ultimate goal of generating resistant and productive domestic pigs, is just beginning,” said ILRI molecular biologist Dr Richard Bishop.
According to Bishop, experimental live attenuated vaccines already exist, providing a path for developing a stronger vaccine against this disease. He noted that more cost-effective prophylactic control through a combination of vaccination, use of genetically resistant pigs and improved management has the potential to both mitigate the impacts of this disease on small-scale farmers in Africa and to reduce the threat to global pork production, and hence global food security.
The disease is still emerging in Africa and in the last 20 years, it has spread to parts of West Africa, Madagascar, Mauritius and most recently (in 2011) to Chad from Cameroon.