Ticks Found on Wild Pigs Capable of Causing Life Threatening Food Allergy



By: Josh Helcel, Extension Associate

Recent research confirmed that tick species commonly found on wild pigs (Sus scrofa) are capable of transmitting a potentially life threatening food allergy to animal food products including beef and pork (Commins and Plattis-Mills 2013).  The condition, known as IgE Ab response to Alpha-gal, emerged in the eastern, central, and southern portions of the US in 2009 with 24 human cases initially reported (Commins et al. 2009).  However, subsequent research indicated that in less than 3 years thousands of cases were documented in the US (Commins et al. 2012).  Transmitting tick species included the Lone Star Tick (Amblyomma americanum) and the Blacklegged tick (Ixodes scapularis); species that research suggested may infest as many as 75% of wild pigs in Texas (Sanders 2011). The overlap in distribution between expanding wild pig populations and Ixodid (hard shelled) tick species (Figure 1) raises concern that these animals may aid in the transmission of a variety of tick-borne illnesses to livestock, wildlife and humans (Sanders et al. 2013; Helcel et al. 2016).

Figure 1.  The U.S. distribution of wild pigs (top right) overlaps with a number of Ixodid tick species capable of transmitting tick-borne illnesses to livestock, wildlife and humans. Blacklegged ticks (bottom right) and Western Blacklegged ticks (top left) are capable of transmitting a number of illnesses including Rickettsia, Ehrlichia, and Lyme disease. Research indicated the Lone Star tick (bottom left) transmitted the majority of cases of IgE Ab response to Alpha-gal (Commins and Plattis-Mills 2013).

In 2012 research estimated there were approximately 2.6 million wild pigs in Texas (Timmons 2012), a figure that today could potentially exceed 5 million animals.  The potential for wild pigs to introduce ticks to areas used by livestock and humans (Figure 2) is compounded by their reproductive capacity, relatively large home range, and tendency breach most types of fencing (Reidy et al. 2007). This has led organizations such as Texas Wildlife Services to enact tick monitoring efforts for wild pigs in south Texas; where incursions of cattle tick fever from Mexico continue to threaten the TX and US animal economy (M. Bodenchuk, personal communication, August 13, 2015).  In addition to concerns over cattle tick fever, Sanders (2011) estimated Rickettsia, Ehrlichia, and Borrelia exposures at 28%, 13%, and 2%, respectively out of 888 wild pigs sampled across Texas.

Figure 2.  Shared habitat and direct interactions are ways in which wild pigs can introduce ticks to livestock.  (Image credit Dawn Tschirhart)

Texas A&M AgriLife Extension Service has recently made available a new publication on wild pigs and ticks. This resource provides information on wild pigs and ticks and addresses concerns related to the potential role of wild pigs in transmitting tick-borne illnesses to livestock, wildlife and humans. It explains the types, life cycles and distribution of ticks commonly found on wild pigs in Texas and details the associated illnesses with each tick species of concern. It describes the economic impacts of tick-borne illness in livestock and addresses control strategies to reduce overall tick abundance. Also explained are symptoms of tick borne illness, instructions for proper tick removal and precautions that can be taken when handling wild pigs or recreating in outdoor areas where ticks may be present.

To learn more, please visit Our Website or the AgriLife Bookstore

For free educational programming or technical assistance with wild pigs please contact us:

Josh Helcel, Central and North Central Texas, 512-554-3785, josh.helcel@tamu.edu

Literature Cited

Commins, S.P., S.M. Satinover, J. Hosen et al. 2009. Delayed anaphylaxis, angioedema, or urticaria after consumption of red meat in patients with IgE antibodies specific for galactose-alpha-1,3-galactose. J Allergy Clin Immunol.; 123:426–33.

Commins, S.P., L. A. Kelly, E. Rönmark et al. 2012. Galactose-α-1,3-galactose-specific IgE is associated with anaphylaxis but not asthma. Am J Respir Crit Care Med. 185:723–30.

Commins, S. P., and T. A. E. Platts-Mills 2013. Delayed anaphylaxis to red meat in patients with IgE specific for galactose alpha-1,3-galactose (alpha-gal). Current Allergy and Asthma Reports, 13(1), 72–77.

Helcel, J., P. Teel, M. Tyson, J. Cash, T. Hensley and J. C. Cathey. 2016. Wild pigs and ticks: Implications for livestock production, human and animal health. Texas A&M AgriLife Extension Service EWF-033.

Reidy, M. M.  2007.  The efficacy of electric fencing and population estimation techniques for feral pigs.  Thesis, Texas A&M University, Kingsville, USA.

Sanders, D.M., A.L. Schuster, P. W. McCardle, O. F. Strey, T. L. Blankenship, and P. D. Teel. 2013. Ixodid ticks associated with feral swine in Texas. Journal of Vector Ecology. 38:361–373.

Sanders, D. M. 2011. Ticks and tick-borne pathogens associated with feral swine in Edwards plateau and gulf prairies and marshes ecoregions of Texas. 57 pages; 2011-01-01.

Timmons, J. B., B. Higginbotham, R. Lopez, J. C. Cathey, J. Mellish, J. Griffin, A. Sumrall and K. Skow. 2012.  Feral hog population growth, density and harvest in Texas. Texas A&M AgriLife Extension Service SP-472.