Chapter 8 – Produce Contamination by Other Wildlife

The list of zoonotic pathogens that have the potential to infect humans through a fresh produce vehicle is extensive. The following zoonotic pathogens have been reported to be carried by one or more species of wildlife and have the potential to be transmitted to humans through fresh produce: Viruses – Hepatitis E; Bacteria – Campylobacter spp., Salmonella enterica, pathogenic E. coli, Listeria monocytogenes, Yersinia enterocolitica, and Arcobacter spp.; Protozoa – Cryptosporidium parvum, Giardia spp., and Toxoplasma gondii; and Helminthes – the nematodes Ascaris suum, Toxocara canis and cati, Tosascaris leonine, Lagochilascaris minor, and both Angiostrongylus catonensis and costaricensis, and the trematodes Fasciola hepatica and gigantica and Fasciolopsis buski. Many of these organisms are rarely associated with human illness; however, several are among those currently listed as the most significant emerging foodborne pathogens. Establishing the role that wildlife and feral domestic animals play in produce-borne human illness is very difficult, as evidenced by the number of outbreak investigations that imply involvement of wildlife in spite of a lack of conclusive evidence that this has indeed occurred. Almost certainly, some human illnesses with zoonotic pathogens are directly linked to wild animals; however, the frequency with which this occurs is unknown.