Population biology of helminth infections of veterinary importance and its relevance to control

  • Gary Smith
Part of the Monographiae Biologicae book series (MOBI, volume 67)


This chapter examines how mathematical models can be helpful in the design and evaluation of control programs directed against the debilitating and sometimes fatal diseases that arise when domestic ruminants are infected with helminth parasites. The models comprise hypotheses about the natural processes which control and regulate parasite abundance. The empirical description of regulatory processes is described in detail since these processes act in such a way as to confine parasite population density between certain bounds and so tend to work in opposition to disease control strategies.

It is demonstrated that models can rank strategies in order of efficacy — at least in parasitological terms — but currently give no good indication of how much better one strategy might be than another in terms of the things that most interest the farmer: the net return on his investment in parasite control, and the risk associated with that investment. It is argued that the proper use of the models described here is not to replace anthelmintic field trials but rather as tools to guide our thinking, a means of refining judgments about the strategies most likely to work, and a framework for the development of new methods of disease control. Models should reduce the number of field trials required to evaluate the possible permutations of some new strategy because we will already have some very good idea of which will work best.


Population Biology Helminth Infection Parasite Burden Helminth Parasite Parasite Abundance 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Kluwer Academic Publishers 1992

Authors and Affiliations

  • Gary Smith
    • 1
  1. 1.Section of Animal Health EconomicsUniversity of Pennsylvania, School of Veterinary MedicineKennett SquareUSA

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