(Bloomberg) -- Hog farms found using illegal vaccines will be punished under China’s intensified efforts to arrest its African swine fever crisis.

Homemade, experimental and imported vaccines against the pig-killing virus are prohibited, and risk untold biosafety hazards for the world’s largest pork industry, Yang Zhenhai, head of the Ministry of Agriculture and Rural Affairs’ animal husbandry bureau, told reporters in Beijing on Friday.

“Farms that use these vaccines won’t be able to effectively prevent the disease and they could spread it further -- something we take seriously,” Yang said. The ministry will punish those who use, produce or sell these products, he said. Those found guilty may be liable for fines of as much as 200,000 yuan ($28,500).

A ministry hotline for citizens to report outbreak “irregularities” will offer cash rewards of 30,000 yuan. The measures aim to halt the swine contagion, which Rabobank estimated this month has caused China’s hog herd to more than halve to less than 200 million head since the first case was reported in August last year.

Some domestic research institutes are conducting studies on vaccines, but these remain at the pre-clinical stage, while the safety of genetically modified organisms is evaluated. While none has been approved yet for field trials, the ministry is pushing for their development to ensure the production of safe, effective and high-quality immunizations, Yang said.

Unauthorized experimental vaccines against African swine fever virus have been used to immunize millions of hogs in China, creating “chaos” because of their varying levels of efficacy, Caixin reported last week.

To contact Bloomberg News staff for this story: Niu Shuping in Beijing at nshuping@bloomberg.net

To contact the editors responsible for this story: Anna Kitanaka at akitanaka@bloomberg.net, Jason Gale, Alexander Kwiatkowski

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