Japanese authorities have detected cases of equine influenza at three horse breeding farms in Kumamoto prefecture. Preventive measures have already been implemented, including isolating infected horses, administering vaccines, and disinfecting facilities to contain the spread. It is the first outbreak of equine influenza in Japan since 2008. The disease is highly contagious and affects horses, donkeys, and other equine species. It spreads easily and can lead to severe economic consequences for horse breeders and livestock owners. A previous outbreak in 2007 devastated the horse racing sector in Japan, resulting even in the cancellation of racing events.
Young horses are the most susceptible to infection, especially when living in large groups. Transmission may be direct through inhalation or indirect through clothing and shared water. The epidemiologic outcome depends on the characteristics of the circulating virus and the immune status of a given population of horses at the time of exposure. Frequent natural exposure and regular vaccination may contribute to better protection from the virus, though immunocompromised horses remain always at risk of severe disease.
