Study finds feral pigs had antibodies to zoonotic organisms

Testing at two Texas abattoirs revealed that feral pigs had been exposed to zoonotic bacteria, viruses, and parasites.

Authors of a scientific article published in August (J Food Prot 2017;80:1239-1242) collected blood samples from 376 feral swine at slaughter in 2015. Forty-nine percent had serum antibodies against Leptospira serovars, 14 percent against influenza A virus, 9 percent against Toxoplasma gondii, and 3.5 percent against Trichinella spiralis.

"Because the likelihood of direct contact with aerosolized particles and infected blood, urine, or tissues is elevated at slaughter facilities, our results indicate that employees should be aware of the potential for exposure," the article states. "It also suggests that others who come in direct contact with feral swine, such as hunters, wildlife biologists, or veterinarians, should be aware of the risk of becoming infected. Furthermore, consumers of both harvested and processed feral swine meat should also be aware of the increased risk of parasites, compared with pork from domestic swine, and should ensure that appropriate precautions are followed, such as cooking meat to the appropriate temperature."

The authors noted that they had not tested for other zoonotic pathogens found in feral swine. Those include Escherichia coli, Salmonella organisms, and hepatitis E virus.

The authors recommended further study of zoonotic antigens and parasites in feral swine. Medical programs should monitor abattoir employee health, and meat packaging should include warnings, they said.

Four of the six authors are with the Wildlife Services program in the Department of Agriculture's Animal and Plant Health Inspection Service, one is with the USDA Food Safety and Inspection Service, and the other is with the Texas A&M University Veterinary Medical Diagnostic Laboratory.