Feral hogs have long been known as an invasive, disease-carrying scourge on the Louisiana landscape, wreaking havoc on agriculture, hunting leases and even other wildlife caught in their wake.
In the last 10 years they've spread rapidly, and recent evidence suggests they are now present in all 64 of the state's parishes.
But a study conducted last summer by the LSU Ag Center's School of Renewable Natural Resources shows an alarming correlation between feral hogs and the presence of a multitude of pathogens including E. coli, leptospirosis and salmonellosis in water bodies in Central Louisiana.
The three-month project sampled 40 bodies of water between Alexandria and Natchitoches adjacent to the Kisatchie National Forest, and the news wasn't good for humans - or other wildlife.
"Based on one or more criteria, every site evaluated was potentially unsafe for human-water and wildlife-water contact," the report states.
At 22 of the sites, DNA fingerprinting positively matched E. coli with fecal samples from feral hogs. Pathogens that cause leptospirosis were found at 34 sites, Klebsiella pneumonia was found at all 40 sites and salmonellosis was located at nine sites, the report states.
According to the report, the pathogens can cause severe intestinal diseases, kidney damage, liver failure or mortality (if untreated) in humans. For other wildlife, including white-tailed deer, turkeys, squirrels, raccoons and waterfowl, they can cause kidney damage, renal failure, spontaneous abortions, respiratory illnesses, gastrointestinal illnesses and death.
Scott Durham, director of species management for the Louisiana Department of Wildlife and Fisheries, said the research was an eye-opener.
"I think it was probably a little bit surprising how many of those pathogens were there, and the levels the researchers found them at," Durham said. "I don't think it surprised us that hogs were carriers and sources of these diseases, but this study gives some real good evidence using DNA sampling techniques that drilled home the way the diseases seem to be getting from one place to another."
Aside from the potential human health risks associated with the pathogens in the water, Durham said the research results have broad implications for other wildlife - and the biologists who study them.
DNA fingerprinting in the study revealed that feral hog family groups were moving - or being moved - great distances in the region, up to 30 miles at a time.
"The take home message is to get rid of the pigs somehow, some way, over time, and not move them around. It's illegal to transport and release them," Durham said. "We have to contain them and eliminate them. They look to be the main way these pathogens are being brought around."
Durham said the state's Department of Health and Hospitals had reviewed the report results as they related to human safety, and may be commenting on it regarding recreational activities like swimming, boating, hunting and kayaking in the area.
"Some of the levels were definitely unsafe for humans," he said.
To view the entire LSU report, click here.
