Feral Swine and Brucellosis: How Hunters Can Minimize Risk
The Professor's Blog 02.13.13
In the United States, the non-native and invasive feral swine (Sus scrofa) population has quadrupled over the past 10 years and is currently estimated to be approximately 4 million animals ranging across at least 37 states. As the feral swine population expands and feral swine hunting becomes more popular, there is increased interaction and greater potential for disease transmission among feral swine, humans, commercial swine, and wildlife.
From 2007 to 2010, we conducted a disease survey (pdf) of over 600 feral swine across 13 North Carolina counties (where the majority of the state’s commercial swine production occurs). Although a variety of diseases were tested, the most notable results were the detection of the bacteria Brucella suis. Brucella suis is typically screened for by the National Wildlife Disease Program and, until this research, feral swine were antibody-negative in eastern North Carolina. Currently, B. suis does not occur in US domestic swine operations.
The presence of B. suis in a feral swine population that is routinely hunted raises concern about disease transmission to humans. In pigs, B. suis is a bacteria that can cause abortion in pregnant females, reduced milk production, and infertility. Importantly, B. suis is zoonotic (can be transferred from wildlife to humans; once transmitted it is called brucellosis) and can be transmitted to humans through cuts on the skin from handling the infected animals or inhaling the waste product of the animal.
In humans, brucellosis causes a variety of symptoms, such as fever, weight loss, fatigue, weakness, chills, joint pain, headaches and depression. Brucellosis can develop weeks to months after exposure, can last for days to months, and can be debilitating if not treated. Recent cases of B. suis infection in feral swine hunters were linked to butchering of swine but not to consumption of the meat. Diagnosing brucellosis can be difficult because of the wide-ranging and non-specific symptoms. Therefore, it is very important to inform your health care provider if you have come in contact with feral swine. Once identified, brucellosis is treated with antibiotics.
While in the field, there are some simple precautions that hunters should take to protect themself. First, hunters should always were long sleeves, gloves, and eye protection when cleaning any game animal. Your hands may have small cuts and cracks that can provide points for infectious diseases to enter your body. Further, avoiding unprotected direct contact with blood, fecal matter, the brain and spinal cord, and organs will help minimize risks. After cleaning the animal, be sure to clean and disinfect all knives, clothing, or cleaning surfaces and absolutely make sure to wash your hands frequently and carefully with soap and water. Additionally, B. suis transmission can be prevented by properly cooking the meat.
I hope you continue to follow this blog. Next week, I will be highlighting more of our research on feral swine. Specifically, Toxoplasma gondii and Trichinella spp.
Also, I encourage you to ask questions. I will answer them in upcoming blogs.
I grew up in Michigan where I spent my early years hunting and fishing with family and friends and where I learned the intrinsic value of the outdoors and wildlife. While pursuing a graduate education in my twenties, I was fortunate enough to live in northern Indiana and western and eastern South Dakota where I took full advantage of the unique hunting and fishing opportunities in each state. After graduate school, my first job as a state wildlife biologist brought me to southern Minnesota where I immersed myself in the science of wildlife and habitat management and began to really appreciate the connections of research and management. In 2004, I moved my wife and two children to North Carolina where I have dedicated my career to mentoring the next generation of wildlife biologists and educating the general public about wildlife research and management.
The goals of my blog are to help connect all of you to the science of wildlife management. I plan to bring the latest scientific research to you in a casual, fun, and informative format. Everyone from the die-hard hunter, to the professional land manger, and the everyday homeowner encounters wildlife on a daily basis. Helping people understand the science behind wildlife management, the laws that govern wildlife and their habitats, the ways citizens can use research to enhance their land and hunting experience, and dispelling the myths that surround wildlife, while fostering an appreciation for the natural world are my passions. Hopefully, that will come across in my posts and I encourage everyone to take advantage of the special question and answer section where I will do my best to offer you the latest scientific research to help enhance your enjoyment of the natural world.
Credentials
I earned a Bachelor of Science from Central Michigan University (1990), a Master of Science in Behavioral Ecology from Purdue University (1994), and a Ph.D. in Wildlife Management from South Dakota State University (1998). From 1999-2004, I worked as a research scientist for the Minnesota Department of Natural Resources. Since 2004, I have been a professor in the Fisheries, Wildlife, and Conservation Biology Program at North Carolina State University (NCSU) where my research interests include population ecology, habitat use and management of big game species and predators, predator/prey interactions, human/wildlife interaction, and wildlife and zoonotic diseases. Specifically, I have conducted research on white-tailed deer, coyotes, feral pigs, American woodcock, fox squirrels, wild turkey, Canada geese, river otters, amphibians, and reptiles, and other species.
I am a member of The Wildlife Society, American Society of Mammalogists, Great Plains Natural Science Society, Jack H. Berryman Institute, Scientific Advisory Panel, North Carolina Prescribed Fire Council, and the North Carolina Herpetological Society. In 2002, I became a ‘Certified Wildlife Biologist’ via The Wildlife Society. I have served as an Associate Editor of the Prairie Naturalist and the Proceedings of the Southeastern Association of Fish and Wildlife Agencies. Additionally, I am past-President of the Great Plains Natural Science Society and the North Carolina Chapter of The Wildlife Society.
