How bad is the African swine fever spreading across China? Bad, authorities say.

The epidemic has spread to 17 provinces, including the pig-breeding hub in southern China, three central government ministries said Wednesday in a rare joint public statement. They are the Ministry of Agriculture, the Ministry of Transport and the Ministry of Public Security.

Although African swine fever is highly contagious, it doesn’t affect humans. However, it is always fatal in pigs, one of the nation’s leading food sources. China is home to half the world’s domestic pigs. Hundreds of thousands of infected hogs have been culled since early August, when China reported the first outbreak in the northeastern province of Liaoning.

In their joint statement, the three agencies called for local authorities and multiple departments to cooperate in preventing the disease from spreading further.