TOKYO – An outbreak of classical swine fever (CSF) has spread to five prefectures in Japan and animal health officials are struggling to contain the disease.

The Ministry of Agriculture, Forestry and Fisheries in Tokyo, reported 18 outbreaks to the World Animal Health Organization (OIE) since September 2018. The most recent outbreak occurred in Gifu Prefecture, which has reported multiple outbreaks of CSF during the same period. OIE reported 16,707 animals, including wild boar and pigs raised for meat, have been culled since the outbreak started.

So far, the outbreak has spread to Aichi, Shiga, Nagano and Osaka Prefectures in addition to Gifu. Measures employed to stamp out the disease include movement controls, surveillance within and outside the containment zone, screening, quarantine, disinfection and official disposal of carcasses, byproducts and waste, among other measures.

The disease was first detected on Sept. 3, 2018, when one sow, 26 fattening pigs and two piglets were found dead at a farm in Gifu Prefecture, according to an OIE report. Samples taken from the affected pigs tested positive for Pestivirus which causes CSF. Movement and shipment restrictions were imposed on hog farms within a 3 km to 10 km radius of the affected premises, and 581 animals were culled.

Classical swine fever, also called swine cholera, is a contagious and often fatal disease of pigs characterized by fever, lethargy, vomiting, discoloration of the ears, lower abdomen and legs, and yellowish diarrhea. The disease does not affect humans.