LSU AGCENTER veterinarian Steve Nicholson says anthrax is nothing new in Louisiana, since the disease periodically has cropped up in livestock in the state.
Recent terrorist activities and anthrax outbreaks in humans in Florida and New York have increased the attention placed on the disease, but Nicholson and other experts point out it has been around for a long time — as a disease that occasionally strikes livestock.
“Louisiana has a history of anthrax worth recalling while people are speculating about every case that pops up and whether it is related to biological warfare,” Nicholson said this week. “It is likely anthrax bacterial spores still persist in soils in the river parishes south and west of Baton Rouge where a major outbreak occurred in livestock in 1971.”
The LSU AgCenter veterinarian and specialist in veterinary toxicology said outbreaks also have occurred in livestock along floodplains of the Red River and in northeastern Louisiana. That's why many livestock owners continue to vaccinate their animals annually to prevent the disease.
“Although hundreds of animals have died of anthrax in Louisiana, human cases have been rare,” Nicholson says, explaining contact with blood or other discharges of infected animals has resulted in the skin form of anthrax in individuals handling or disposing of the carcasses. In those cases, he says, medical treatment was effective and that family members and co-workers did not contract the disease.
“Experts tell us that anthrax, although infectious, is not considered contagious, person to person,” the LSU AgCenter veterinarian added. “And history has shown that people examining, treating and disposing of infected animals must come into contact with blood or other discharges to contract the disease.”
Livestock become infected by ingesting anthrax spores while grazing, according to experts.
“As they graze, they swallow some dirt,” Nicholson said, adding that spores are harbored in the soil.
“It seems the environmental effects from periods of drought followed by flooding of pastures often precede an outbreak,” he said. “The spores in the soil may float and then become concentrated on the soil surface as water puddles dry up.”
On the other hand, the veterinarian says he is not aware of humans becoming infected from contact with such soil.
For more information on anthrax, USDA maintains Websites regarding the disease and its effects on humans and animals since long before the latest cases emerged.