Speaking to Global Meat News, Dr Bernard Vallat said ASF was “very difficult to control” and the fact that African nations affected by outbreaks had no budget to pay compensation for dead animals meant there was an incentive for farmers to hide suspected cases.
ASF was yesterday confirmed in Zimbabwe, the OIE said, the first outbreak in the country since 1992. The outbreak was detected in free range indigenous pigs in the villages along the northern border with Mozambique. A total of 50 animals are reported to have died.
Quarantine has been imposed in the Mount Darwin district with pigs not allowed in or out. Carcasses are being burnt and buried, said the OIE, and weekly inspections will be carried out in the affected villages.
This outbreak is the latest in a fresh round of ASF notifications around the world in the past few days, with other new cases confirmed in Estonia and Russia.
This year, cases have been confirmed in Cabo Verde, Chad, Cote D’Ivoire, Estonia, Latvia, Lithuania, Nigeria, Poland, Russia, Ukraine and now Zimbabwe. The most intense areas of infection have been in the Baltic states, where there are large wild boar populations. In Latvia, the worst hit country, there have been 414 cases; in Estonia 128 cases are confirmed; in Russia 110 and in Lithuania 104.
Dr Vallat told Global Meat News most cases in the Baltic states have been individual reports of dead wild boar found in woodland, rather than substantial outbreaks in domestic or commercial herds. He welcomed EFSA’s new advice on preventing the spread of ASF in the European Union.
In new advice issued in July, EFSA recommends that while various individual measures applied in isolation are largely ineffective, a combination of several measures including targeted hunting, removal of carcasses in the wild and a strict feeding ban on wild boar was the best way for member states to proceed. “Combined, these would result in a reduced reproduction of wild boar and lead to a containment of the disease,” EFSA said in a statement.
Dr Vallat said individual European states should work closely with hunters to control boar populations in affected areas. He warned however that over-culling could be counterproductive, because it may cause boar to travel miles away from an infected site, and spread the virus to new areas.
He described the risk of ASF crossing into Germany as “very important” but said plans in place to control an outbreak in western Europe, including isolating and slaughtering at any affected farms, co-operation with hunters, and enforcing the ban on swill feeding had the support of the OIE.
Russia had struggled to control the virus, said Dr Vallat, because it had multiple administrative regions all with different policies. “There is no chain of command,” he said.
African swine fever (ASF) is a highly contagious haemorrhagic disease of pigs, warthogs, and wild boar. It kills animals affected within two to ten days and is characterised by high fever, loss of appetite, haemorrhages in the skin and internal organs. There is no cure and no vaccine, and it can be transmitted via ticks, meaning there do not need to be any pigs or boar in an area for the virus to survive there.