Where exactly did African swine fever come from? Understanding the source in one article

Regarding the African swine fever outbreaks that keep appearing within China, the Ministry of Agriculture and Rural Affairs clearly stated today that China's African swine fever outbreaks were introduced from abroad, and that for some time to come the disease will still show a pattern of scattered, isolated cases, but a regional explosive epidemic is unlikely.

As for the source of China's African swine fever outbreaks, it was clearly stated that this disease was introduced from abroad. Because before 2018, China had never had African swine fever. Molecular epidemiological studies show that the African swine fever virus introduced into China belongs to genotype II, with whole-genome sequence homology of about 99.95% with the strains published by Georgia, Russia and Poland.

Although there is no definitive conclusion yet, clues already point the source of China's African swine fever outbreaks to Russia.

Experts say one possible inference is that during the Russia World Cup, Chinese people traveling abroad to watch matches bought virus-carrying meat products from Russia along the way. These meat products were not all consumed, and the leftovers became swill. Subsequently, the swill was used to feed pigs, triggering the outbreak.

At the same time, it should also be pointed out that since African swine fever was first discovered in Kenya in 1921, it has become a global threat; even if it had not spread to China through the above possible channels, it might later have arrived by other routes.

Generally, there are four main routes by which African swine fever is introduced across borders: first, international trade in and smuggling of live pigs and their products; second, pork and pork products carried by international travelers; third, kitchen waste on international transport vehicles; and fourth, the migration of wild boars.