Anthrax Qs and As from the Texas Animal Health Commission

Anthrax is a naturally occuring disease with worldwide distribution. It is caused by Bacillus anthracis, a spore-forming bacteria that can remain alive, but dormant in the soil for many years. The bacteria can “bloom” and contaminate surface soil and grass after periods of wet, cool weather, followed by several weeks of hot, dry conditions. Grazing animals such as cattle, sheep, goats, exotic and domestic deer and horses, ingest anthrax bacteria when they consume contaminated grass. By the time an animal displays signs of disease, including staggering, trembling, convulsions, or bleeding from body openings, death usually follows. Domestic and wild swine are fairly resistant to anthrax and although they may become ill, some of these animals recover fully. Anthrax outbreaks depend on two factors working together: the presence of the spores in the soil and suitable weather conditions. Outbreaks usually end when cool weather arrives and the bacteria becomes dormant. An outbreak may occur one year, but not the next. Death loss may occur in one pasture, while animals nearby remain healthy. Anthrax can occur anywhere, but in Texas, cases most often are confined to a triangular area bounded by the towns of Uvalde, Ozona and Eagle Pass. This area includes portions of Crockett, Val Verde, Sutton, Edwards, Kinney and Maverick Counties. In these counties, many livestock producers routinely vaccinate livestock against the disease. When anthrax outbreak begins, veterinarians will have the initial cases confirmed through laboratory tests conducted at the Texas Veterinary Medical Diagnostic Laboratory in College Station. Subsequent cases in an outbreak are to be expected and may be diagnosed clinically, based on disease signs and sudden death loss. Anthrax is a reportable disease, and the Texas Animal Health Commission (TAHC) is to be notified of confirmed and suspected cases. Reports can be made to TAHC area offices, or to the TAHC headquarters at 1-800-550-8242, where a veterinarian is on call 24 hours a day. The Situation: Summer 2001 By mid-July 2001, seven ranches in Val Verde, Uvalde and Edwards had laboratory confirmed cases of anthrax in deer and livestock. Private veterinary practitioners and ranchers in these counties and Real, Kinney and western Bandera Counties also had reported losses due to the disease. A “significant” white-tailed deer death loss was reported along in southeast Edwards and southwest Real Counties. During an Outbreak, Protecting Animal Health An effective anthrax vaccine can be purchased through private veterinary practitioners, feed stores or animal health product distributors. The injection can be administered by private veterinary practitioners or ranchers and is recommended for: * livestock residing in or near an outbreak * animals that will be moved into the area, such as horses transported to trail rides. When administering the vaccine, wear a long-sleeved shirt and use latex or work gloves to prevent skin contamination with this “live” vaccine. Consult your physician for treatment if you suffer a “needle stick,” splash vaccine in cuts or scratches, or if you develop a sore after handling vaccine or livestock. During an outbreak, white-tailed deer often suffer the most from the disease,as they cannot be “rounded up” and handled like domestic or farmed exotic livestock. Furthermore, the anthrax vaccine has not been approved for use in deer. Carcass Disposal To prevent contaminating the ground with the anthrax spores or organisms, TAHC regulations require that property or livestock owners thoroughly burn carcasses of animals that may have died from anthrax. Wear long sleeves and protect your hands with gloves, and do not move or open bloated carcasses, as this could release bacteria into the air, causing further disease spread. Do not salvage hides, horns, antlers or any other tissue from the carcasses. If the animal was housed in a barn, burn the animal’s bedding, manure and the surrounding soil. To disinfect panels, trailers or equipment, use an ammonia-based disinfectant, lebeled as effective for anthrax. Follow label directions to prevent respiratory irritation! Pastures cannot be disinfected with chemicals. Only burning ensures that anthrax bacteria has been killed. Due to environmental concerns, do not use heavy oils or tires to burn carcasses. Fuels permitted by the Texas Natural Resource Conservation Commission (TNRCC) include gasoline, diesel or wood. Care should be taken to keep fires from “getting out of hand.” In counties under a burn ban, burning must be coordinated with local fire authorities. Vaccinate healthy livestock and move the animals away from the carcasses, to clean pastures, if possible. Other Safety Precautions Wash your hands thoroughly after handling livestock. Ranchers can contract a skin form of anthrax that requires specific antibiotic treatment. See your physician if you develop a sore or lesions after handling vaccine or livestock or burning carcasses. Keep dogs out of pastures and away from carcasses during an anthrax outbreak. Although dogs are reportedly resistant to anthrax, they can develop infection from the bacteria and may require treatment. Do not swim in stock tanks or stagnant ponds in pastures where death losses have occurred. Streams are considered safer, as the moving water will dilute organisms. Report animal carcasses in streams or rivers to local sheriff or police departments. During an outbreak, do not consume wild hogs shot in an affected area. Swine may have fed on carcasses. Although swine are resistant to anthrax, they may temporarily harbor the bacteria. During cool weather, wild hogs will be free of the disease. As always, the TAHC recommends hunters wear latex gloves when processing game, to prevent potential exposure to bacteria, viruses or parasites. Thoroughly cooked meat is considered safe to eat. Do not collect antlers, skulls or horns from animals. Anthrax can survive, even if bones are bleached.

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