In three provinces of South Africa and near the Ghanaian capital, outbreaks of African swine fever (ASF) have been confirmed in domestic pigs.
Over the past week, the veterinary authority of South Africa has officially recorded a further three new outbreaks of African swine fever (ASF) in domestic pigs.
According to the latest reports to the World Organisation for Animal Health (OIE), first of these occurred in mid-June in the O.R. Tambo region of Eastern Cape. Of the 50 animals in the village herd, three pigs died. A previous outbreak had been confirmed in the same region in January.
In mid-July, the virus was detected in another village herd, this time in Western Cape. Of the 100 pigs in the herd near Stellenbosch in the Cape Winelands region, there were 20 cases. Of these, 17 died and three more were culled.
The country’s third recent outbreak was in Gauteng province, and it was confirmed at the start of August. Nine of the 27 animals in a backyard herd near Ekurhuleni died.
For a previous outbreak in the same ASF series, figures for the number of pigs involved have been adjusted. Now it appears that there were 450 affected animals in a village herd in the Lejweleputswa region of Free State. According to the update, 48 of the pigs died, 70 were slaughtered for consumption, and 380 were culled to prevent the further spread of infection.
Based on OIE reports, ASF has been circulating in South Africa for more than two years. Directly affected have been more than 43,100 pigs in Eastern Cape, Free State, Gauteng, Mpumalanga and Western Cape.
ASF proves hard to control in South Africa
Citing data from the department for agriculture, Food for Mzansi reported this month that 101 ASF outbreaks have been confirmed in South Africa since April 2019 in at least four provinces. With 41 and 11 outbreaks, respectively, Gauteng and Western Cape has been worst affected by the disease.
The disease is particularly hard to control, said a veterinarian with CS Vets, because the virus can remain viable in a range of environments for a long time. As well as other live pigs — wild and domestic — this includes pig meat products, feed, vehicles, and people’s clothes and footwear.
As a result, pig owners are being urged to maintain biosecurity, restrict access to essential visitors only, to purchase feed only from a reputable source, and to cease swill feeding.
Uganda: High-level meeting to assess ASF control needs
At the end of July, local pig industry stakeholders met with international experts to assess the country’s requirements to prevent the potentially disastrous impacts of ASF on pig farmers and pork production. The meeting was organized by the United Nations’ Food and Agriculture Organization (FAO).
According to the FAO, ASF is endemic in the East African state. Adding to the challenges of disease control are the absence of basic biosecurity, a tradition of free-range pig farming, and uncontrolled animal movements. Furthermore, slaughterhouses are often poorly equipped, and waste is accessible to scavenging pigs and other animals. When quarantine and movement restrictions are imposed after a suspected disease outbreak, compliance is sometimes poor.
As long as outbreaks continue to occur sporadically in the country, there is little incentive for pig owners to invest in improved biosecurity measures, the FAO reports. The risk of a further spread of ASF in Uganda appears likely to persist until a safe, effective and affordable vaccine becomes available.
Among the main recommendations to emerge from the meeting were the importance of maintaining ASF-free areas in Uganda through strict biosecurity and disease control measures. Quarantine and movement bans need to be applied strictly, and diagnostic teams need to be prepared to be mobilized rapidly to support local disease control efforts in case of an outbreak. The importance of accurate and timely communication was also stressed.
As well as an absence of vaccines and medication to control ASF, FAO described the rapid and uncontrolled increase in pig populations in some sub-Saharan African countries as a “worrisome dynamic.”
ASF developments in Nigeria
ASF is among the diseases for which controls are set to improve in the West African state.
Together with the FAO, Nigeria’s federal government has launched the In-Service Advanced Veterinary Epidemiology Training program, reports All Africa. Aims of the program are to control animal diseases, and to reduce their impacts in the country.
For the first time, the more dangerous genotype II of the ASF virus has been detected in Nigeria. This is according to scientists at the National Veterinary Research Institute at Makere University. This variant had not previously been identified anywhere in West Africa. The new strain was identified in a sample taken at a pig farm.
In the paper published in the journal Virology, the researchers state that the presence of a new ASF virus genotype not only increases the complex epidemiology of the disease. It will also make ASF control in the region even more challenging.
As well as the “new” genotype II ASF virus, there may be variations also in the genotype I virus family circulating in Nigeria. Results of a University of Ibadan study published in a recent Veterinary World paper revealed a new field strain of the genotype I virus. Its ancestry appeared to be shared with virus samples from Spain and Brazil. Researchers considered that the strain of ASF virus circulating in Nigeria may carry a mutation that has reduced the morbidity and mortality recorded in some outbreaks.
Ghana confirms presence of ASF
Also in West Africa, ASF has been confirmed in Ghana since the start of August.
According to News Ghana, at least 500 pigs had died in the municipality of Kpote-Katamanso, which is near to the capital city, Accra.
OIE considers ASF to be endemic in most sub-Saharan African countries, including Ghana, Nigeria, South Africa and Uganda.
At the end of July, presence of ASF was confirmed for the first time in decades in the Americas. According to local reports, the national army has been involved in controlling the disease in the Dominican Republic, where the virus has already been detected in 11 provinces.
View our continuing coverage of the global African swine fever situation.