What is Anthrax? 

Anthrax is an often-fatal disease caused by infection with bacteria known as Bacillus anthracis. The bacteria forms spores, which are very resistant to environmental conditions such as heating, freezing, chemical disinfection, or dehydration that typically destroy other types of bacteria. Horses may consume the spores while grazing in areas where anthrax has been a problem. 

Clinical Signs: Clinical Signs of an infected animal include fever, muscle tremors, dyspnea (labored breathing), colic, bloody diarrhea, followed by sudden death.

Diagnosis: Diagnosis of Anthrax can be determined by blood test, although rarely done due to high incidence of mortality of infected animals. Therefore, diagnosis generally occurs post-mortem.

Treatment: Treatment is usually not successful due to the rapid progression of the disease. Other animals that may have been infected in the area should be monitored for symptoms.

Prevention: The vaccine currently licensed for use in horses in the United States is a live vaccine that is indicated only for horses pastured in endemic areas.


August 24, 2021
Armstrong County, TX
Confirmed Case(s) - Official Quarantine
July 30, 2019
Uvalde and Crockett County, TX
July 16, 2019
Sutton and Crockett Counties, TX