When most people hear anthrax, they think of the deadly human bioterrorism agent. Thankfully, what occurs in nature is nothing of the sort.
The form of anthrax seen on the news has been specially modified so that it can be inhaled. The biggest actual risk for anthrax is for ruminants like cows and bison.
Anthrax is a bacteria that lives in the soil. In its spore form, it is very hardy and can stay in the soil for decades. When animals like cows, bison, deer, horses, goats, sheep, and pigs ingest the soil that contains anthrax, they usually die within two to three hours. Birds and carnivores, like dogs, are very resistant to the disease.
Anthrax has been around for most of human history, and is found in most countries in the world. Anthrax is not considered contagious in the typical sense, and is more of an environmental disease as it occurs in the soil. There are certain environmental conditions that can predispose an anthrax outbreak. Spring flooding followed by summer drought and disruption of the soil through digging are the most common predispositions.
The good thing about the disease is that there is a very effective vaccine for large animals, so if there is an area that has a history of anthrax in the soil, the anthrax vaccine can be added to the regular yearly vaccines the animals already receive. Since this is not considered a contagious disease, there are no trade implications for the animals.
With anthrax in large animals, most often there are no symptoms as the disease course is so short-lived. If there is any suspicion of an animal anthrax death, be sure to contact your veterinarian about the next steps for diagnosis, body care, and handling. The human health risk for picking up anthrax is very low in this regular setting. The inhalational form seen with bioterrorism is not a risk in a natural setting. As long as none of the infected material is ingested, normally a skin infection is the only potential concern for humans in direct contact.
Normally skin infections of anthrax occur when the infected material enters in through an abrasion on a person’s skin. Thankfully, anthrax is usually very sensitive to antibiotics and typically treated effectively.
The take home points are that anthrax is a bacteria that forms spores and naturally lives in soil in certain areas. The soil has to be consumed by species that are susceptible to it, with cows and bison being the most common species affected. Death from anthrax occurs very quickly in livestock, but the disease is not considered contagious.
The risk to humans is very low, especially if body care is done appropriately. If there are any concerns, be sure to contact your veterinarian.
Dr. Sydney Routley is a 2012 graduate of the Western College of Veterinary Medicine. She was raised in Fort St. John and first started working at the North Peace Veterinary Clinic as a student back in 2004.