Wild Boar CSF Case Confirmed in Chiba
Overview
The Ministry of Agriculture, Forestry and Fisheries announced that the first case of classical swine fever (CSF) in a wild boar in Chiba Prefecture was confirmed in Kamogawa City. PCR testing of the carcass was positive, and following confirmatory testing by the National Institute of Animal Health, it was determined to be positive for a field strain of CSF. In coordination with the prefecture, the ministry will conduct additional oral vaccine distribution, strengthen wild boar surveillance and capture, and provide guidance to pig farmers. CSF does not infect humans.
Key points
- The first CSF infection in a wild boar in Chiba Prefecture was confirmed.
- In coordination with the prefecture, efforts will advance to distribute vaccines, conduct surveillance and capture, and provide guidance to pig farmers.
- CSF does not infect humans.
Overview
On October 10, 2026, the first wild boar infection case in Chiba Prefecture was confirmed in Kamogawa City. The prefecture conducted PCR testing on a carcass found and collected on October 9 and confirmed a positive result.
Based on confirmatory testing by the National Institute of Animal Health, the case was determined to be positive for a field strain of CSF. The institute is described as Japan's only research institution specializing in animal health.
Impact
Because the virus may also be present at the site and in surrounding areas, and could spread via people or vehicles, the Ministry of Agriculture, Forestry and Fisheries says it will take all possible measures.
The ministry requests that people strictly refrain from reporting at the site and in surrounding areas. It also asks producers, other stakeholders, and consumers to help avoid confusion caused by unfounded rumors, and says it will work to provide information promptly and accurately.
Details
Chiba Prefecture is designated as an area where oral CSF vaccination is recommended, and vaccination is underway. In light of this case, additional distribution will be carried out in coordination with the prefecture.
To further assess the infection situation, Chiba Prefecture will strengthen surveillance and capture of wild boars.
Pig farmers in the prefecture will be instructed to administer vaccines in a timely and appropriate manner. They will also receive renewed guidance on rechecking livestock hygiene management and reporting cases early.