ABSTRACT
The epidemiology of nematode infections is remarkably well understood. This is because nematodes were amongst the first recognised pathogens of humans, because there have been several major efforts to achieve control, and because there is now a well developed body of ecological theory to help explain their population dynamics. The long history of people and their worms is explored in detail in other volumes (see, for example, Bundy and Michael, 1996; Cox, 1996; Grove, 1990) and elsewhere in this text, and will not be dealt with here. Similarly there are excellent sources describing the extraordinary efforts of the major control programmes which have been conducted on a scale only exceeded by global vaccination programmes. The Rockefeller hookworm eradication campaign, for example, was started in the southern United States at the turn of this century, extended globally in 1913, and only terminated in the 1950s (Bundy, 1990). The observations by Cort, Styles, Stoll and others laid the foundations for epidemiological understanding and provided a data resource which remains useful today. The extensive literature generated by the forty years of operation of the Japanese national control programme — which reduced the prevalence of intestinal nematode infection from 73% in 1949 to <1% in 1990 (WHO, 1996a) — has also provided an important basis for epidemiological understanding, and the full value of these data is only now beginning to be recognised (Kunni, 1992).
