Spread of deadly pig virus in China hastens vaccine research

A highly contagious disease that kills infected pigs has swept across China and is moving through neighbouring countries. Scientists in China are ramping up efforts to study the virus that causes African swine fever and produce a vaccine. But scientists elsewhere fear that political pressure to make a vaccine quickly could risk introducing chronic strains of the virus.

Although the haemorrhagic disease was first recorded in Kenya in 1921, China’s first case was detected only last August, in the north-eastern city of Shenyang. Since then, the government has reported more than 120 outbreaks across some 30 provinces, autonomous regions or municipalities.

Officials had long feared the arrival of African swine fever in China, which is the world’s largest pig producer. The virus is not harmful to humans, and virologists say the risk of it mutating to become infectious to people is low, but the economic cost of an epidemic is enormous.

With no vaccine or treatment, more than one million pigs have so far been culled in the country to try to contain the outbreaks. An study published in October, two months after the virus was first detected there, reports that the death of some 100,000 pigs — just 10% of the latest figure — had cost the Chinese economy US$20 million¹. A shortage of pigs could also jeopardize worldwide availability of the blood-thinner heparin, warns Paulo Mour?o, a molecular biologist at the Federal University of Rio de Janeiro in Brazil.