China has reported a new outbreak of African swine fever that is threatening the country’s pork industry.

The Ministry of Agriculture and Rural Affairs reported on Friday that the disease had been detected on a farm in the central province of Hunan, where 4 600 pigs were being raised.

Although just 171 of the pigs had died and 270 were found sick, regulations require all pigs on an affected farm must be culled and the area quarantined and decontaminated.

First detected in August 2018, the disease has killed more than 1 million pigs in China.

The disease doesn’t affect humans but is highly contagious in pigs.