Helminth infections of wildlife

Generally, the helminths of wildlife are not well known. For many years helminths of mammals have been collected incidentally, usually during hunting expeditions and incidental post-mortem examinations, and from road kills. Until about 1940 numerous helminths new to science were described and the life cycles of several elucidated. During the years of the second world war and for a considerable period thereafter, the emphasis shifted to investigations of the pathogenic effects of helminths of domestic animals, and thus away from the helminths themselves. Helminths of wildlife received little attention and only a few new species or isolated, interesting cases were reported. From about 1973 onwards there was a renewed interest in the helminths of wildlife. Conservation authorities made material that would otherwise have been discarded or ignored, available to scientists of various disciplines, who advise the conservation authorities of their results and assist them with better management of existing conservation areas.

A complicating factor is that the study of helminth biodiversity is an invasive process which is frowned upon by ecologists, game reserve managers and animal rights activists. Because parasites are internal it is not possible to remove them and leave the host alive, and artificial media for maintaining parasitic larval and adult stages are not in common usage.

The purpose of this module is to provide a limited insight into the fascinating world of the helminths of wildlife. The module is by no means complete, but serves as a starting point for further studies. As far as helminthoses in wildlife are concerned, it is probably best expressed by Robbie Bain’s (2003) comment: “For the time being, an African perspective of the helminths of wildlife is best summed up with the image of the zebra grazing the savannah – fat, happy and full of worms”.