Writer: Steve Hill, (979) 845-2895, newsteam@agnews2.tamu.edu
Contact: Dr. Konrad Eugster, (979) 845-3414, keugster@tvmdl.tamu.edu
COLLEGE STATION — Ranchers should vaccinate cattle and other valuable livestock against anthrax if there is any history of the disease in their area, a state laboratory suggests after confirming an unusual number of cases of the disease.
Five cases of anthrax were confirmed in the last month, said Dr. Konrad Eugster, executive director of the Texas Veterinary Medical Diagnostic Laboratory in College Station. Those cases included three cases in cattle, one in goats and one in deer.
“If they are in an area where anthrax has been found or on a ranch that has had a case any time in the past 30 years, people should vaccinate their animals right away,” Eugster said.
The disease is generally fatal to animals and can be fatal to humans, although it is rarely contracted by people. The last human case in Texas, which was not fatal, was in 1988 in Uvalde, said Jeff Taylor, a staff epidemiologist with the Texas Department of Health infectious disease division.
“Prior to that, it had been in the 1950s that we had last seen any human cases,” Taylor said. “We would say it’s a rare disease in Texas and the United States.”
Anthrax is rarely diagnosed before death in animals because it strikes so quickly and has no noticeable symptoms. Animals usually die within one to three days of the anthrax- causing organism lodging in the body, Eugster said.
“Even if you’re watching your animals like a hawk, all you might notice is a little lethargy,” Eugster said. “For all practical purposes, it’s a sudden, unexplained death.”
Four of the five cases were in an area from South Central Texas to the Big Bend area, in Terrell, Crockett and Uvalde counties.
“This is an area where anthrax cases are more frequent, although we usually only see one or two cases each year in the state,” Eugster said. “Seeing five in a month tells me that we probably are having a larger problem, not only among livestock, but also among deer.”
The fifth case was west of Fort Worth in Parker County, he said.
If livestock owners are uncertain of an area’s anthrax history, they should contact area veterinarians. Cattle, horses and valuable breedstock should be vaccinated, although the vaccination of sheep and goats might be discussed with veterinarians and considered from a cost standpoint because of the difficulty associated with rounding them up, Eugster said.
The bacterium which causes anthrax can survive for up to 30 years in the soil, according to scientific literature on the disease, Eugster said. Carcasses suspected of harboring the disease should not be moved and especially should not be cut open, he said.
“Always call a veterinarian, and do not touch the carcass,” he said.
Spores of the bacteria can travel with blood into the soil, he said. He added that both humans and animals can contract the disease by ingestion, by contact through skin lesions, or — in rare instances — by inhalation.
Instead of moving the carcass, a veterinarian should take a blood or other fluid sample and send it to the diagnostic laboratory for testing, which takes one or two days for results.
Landowners or others with confirmed cases should burn the carcasses where they are found. The most effective and recommended method is by using several old tires heaped on the carcass to be sure the entire carcass burns, Eugster said.
They may also bury the carcass on-site, but it should be buried with lime at least six feet deep, which is impractical in many areas, he noted.
Cattle, sheep, goats, horses, deer and other animals are susceptible to the disease. An inexpensive vaccine is available for livestock, but there is little that can be done for deer in the wild, Eugster said.
“Some people try to incorporate vaccine into feed for the deer, but it’s not an approved method,” he said.
The diagnostic laboratory, which has special equipment, reagents and expertise needed to diagnose anthrax, is the only lab in the state properly set up to do so. Its staff also includes Dr. Howard Whitford, one of the world’s leading experts on anthrax.
Anthrax is found all over the world and in virtually every state of the United States, although within states it tends to be found in specific geographic areas, usually in those with more alkaline soil — those with pH balances of 6 or higher, Eugster said.
Environmental conditions such as warmer weather also appear to have an affect on the number of cases, although exactly which conditions cause more frequent outbreaks is unclear, Eugster said.
“However, once you’ve had it on your ranch, you should consider it contaminated forever and vaccinate annually,” he said.
-30-
VETM TOP