A new form of African swine fever (ASF) has been identified in several farms owned by New Hope Liuhe, China’s fourth-largest producer, the company’s chief science officer Yan Zhichun told Reuters.
Two new strains of ASF have reportedly infected more than 1,000 sows, with industry insiders believing their cause to be ‘illicit vaccines’. The new strains, which are missing key genes present in the wild ASF virus are not killer like that seen previously in the country, but they can cause a chronic condition that reduces the number of healthy piglets born, Mr Yan told Reuters.
New Hope, and many large producers, are culling infected pigs are to prevent the spread. The known infections are limited at present, but if they spread widely, it could once again slash pork output in the world’s top consumer and producer just two years after the previous deadly strain of the virus which decimated China’s pig herd.
Mr Yan said he did not know where these strains originated but: “we find some mild field infections caused by some sort of gene-deleted viruses,.”
There is currently no approved vaccine for African swine fever, but many Chinese farmers struggling to protect their pigs have allegedly resorted to using unapproved products.