TODAY'S MNA PRESS NEWS
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ANTHRAX IN MONTANA; CONFIRMED IN NORTHEASTERN MONTANA
by MONTANA NEWS ASSOCIATION
(Helena, Mont.) - What appears to be a naturally occurring case of anthrax has caused the death of 37 cows from a single herd on tribal land northwest of Culbertson, according to Dr. Tom Linfield, Montana State Veterinarian.
The anthrax has been limited to one ranch, and neighboring ranches have been notified. Producers are alerted to outbreaks so they can consult with their veterinarians and vaccinate their livestock if deemed appropriate.
"The Fort Peck Tribes, Roosevelt county officials, local veterinarians, and the Montana Department of Livestock (DOL) have been working together to contain the disease and to implement preventive measures," Dr. Linfield said.
The dead cows have been placed in two deep burial pits located on the premises. DOL regulations require that carcasses of animals that have died of anthrax be appropriately disposed of, either by burning or by deep burial. The equipment used to handle and bury the animals has been cleaned and disinfected.
Local and state veterinarians have been on-site at the Roosevelt County premises and have taken appropriate measures to prevent further spread of the disease.
"Livestock producers and veterinarians provide the first line of defense against animal disease," Dr. Linfield said. "We are fortunate that the livestock owner and the herd veterinarian recognized the importance of early disease detection and implementation of the appropriate treatment, prevention and control measures. They have made every effort to notify neighbors and help confine the disease to the premises."
All remaining animals from the 250-cow herd have been removed from the affected pasture. All susceptible and potentially exposed livestock on the affected premises have been treated with antibiotics and vaccinated. A second vaccination will be administered after 7-10 days. A quarantine has been placed on the affected premises for approximately 40 days.
"Anthrax tends to be pretty rapid in its course and is a reportable and quarantinable disease because it can cause the rapid loss of a large number of animals in a very short time, and as a zoonotic disease, may have human health implications," Dr. Linfield said.
Anthrax is not usually spread from animal to animal; however, dead animals, if not properly disposed of, can be the source of infection for other animals in the area. Quarantines are imposed to prevent the movement of infected or exposed livestock, thereby limiting further spread of the disease and to help reduce additional environmental contamination.
Vaccination is recommended for livestock residing in or near an outbreak area, or for animals that will be moved into the area. Anyone administering the vaccine should follow the instructions on the product label and consider wearing a long-sleeved shirt and using latex or work gloves to prevent accidental skin contamination with the "live" spore vaccine.
The last confirmed cases of anthrax in Montana were diagnosed in 1999 in unrelated incidents, one in May in Yellowstone County and one in August in McCone County. Prior to 1999, the last case of naturally occurring anthrax in Montana was in 1985.
The organism naturally occurs in the soil in many parts of Montana, as well as other states. North Dakota and South Dakota have had multiple cases of anthrax this season.
Anthrax depends on two factors working together; the presence of anthrax spores in the soil, and suitable weather conditions. The organism forms spores that can survive in the soil for decades.
"When an outbreak is confirmed in a location, it is reasonable to expect additional cases within the same area," Dr. Linfield said.
Grazing animals are typically infected when they ingest or inhale spores on contaminated vegetation or soil. Animals primarily affected are cattle, bison, sheep, goats and horses. In addition, wildlife species such as deer, elk, moose and antelope, as well as wild carnivores, such as coyotes, bobcats, and mountain lions, can also be affected.
Typically, the disease in livestock and wildlife appears following periods of climatic or ecological changes, such as heavy rains or flooding preceded by drought. Spores may also be exposed by wind or water erosion, as well as other soil disturbances, such as excavations. These factors make it possible for an outbreak to occur one year, but not the next.
Signs of the illness usually appear three to seven days after the anthrax spores are inhaled or swallowed, but may occur sooner if a large number of spores are inhaled. Infected animals may exhibit clinical signs such as staggering, trembling, convulsions, or bleeding from body openings, followed by death. Untreated animals may die within 24-48 hours after infection.
Open or bloated carcasses should not be moved since movement could release bacteria into the air or further contaminate the surrounding ground causing further disease spread. Hides, horns, antlers or any other tissue from the carcass cannot be salvaged and must be destroyed.
In cases of sudden, unexplained livestock deaths, owners are urged to contact their herd veterinarians immediately. Anthrax is a reportable disease and the DOL is to be notified of suspected and confirmed cases. The State Veterinarian's office number is 406-444-2043. Animal carcasses in streams or rivers should also be reported to the Department of Livestock.
Hands should be washed thoroughly after handling livestock.
Residents within an anthrax area should keep dogs out of pastures and away from carcasses during an outbreak. Although dogs are reportedly resistant to anthrax, they can develop infection from bacteria and may require treatment.
People and pets should 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.
Anthrax Outbreak Poses Little Risk to Humans, Officials Say
An anthrax outbreak among cattle in northeastern Montana poses little threat to humans, state health officials said Thursday.
Jim Murphy, disease surveillance specialist with the state Department of Public Health and Human Services (DPHHS), said he and his colleagues consulted with the U.S. Centers for Disease Control and Prevention (CDC) about the incident and its potential risk to humans. He said they confirmed that only individuals who came into direct contact with the carcass or bodily fluids of infected cattle need to be monitored for potential exposure to the disease.
"Based on our consultation with the CDC, simply being in the vicinity of the animals suspected or confirmed to have anthrax is not an exposure, and no treatment or observation is necessary," Murphy added. "Even a person who handles a carcass or bodily fluids while wearing gloves would not be considered to be exposed."
There are three types of anthrax: cutaneous (spread through contact with the skin), inhalation, and gastrointestinal (caused by ingesting infected meat or milk). About 95 percent of human anthrax infections occur when the bacterium enters a cut or abrasion on the skin during the handling of the animal or animal products. According to the CDC, inhalation of the bacterium is not a concern in this instance.
Murphy encouraged anyone who may have been in direct contact with the infected cattle to watch for signs and symptoms of the disease for up to a week after possible exposure. Symptoms might include:
* Small, painless sores that develop into blisters and then into skin ulcers with black centers (cutaneous anthrax); or
* Nausea, loss of appetite, vomiting, bloody diarrhea, and fever followed by severe stomach pain (gastrointestinal anthrax).
Murphy suggested that individuals who did come into direct contact with infected animals may want to visit with their medical provider. In most cases, no treatment is indicated, but a medical provider can make appropriate decisions on a case by case basis. If an anthrax infection does develop, early treatment with antibiotics is very effective.
Anthrax is not known to spread from person to person.