Hookworm and roundworm infections in farm-worker communities in the large-scale agricultural sector in Zimbabwe.

Surveys were carried out to assess the prevalences and intensities of hookworm and roundworm infections in 15 farm-worker communities in Zimbabwe with poor living conditions. Examination of 1635 faecal samples showed that hookworms (Necator americanus and Ancylostoma duodenale) were the commonest helminths (61.7% of infections). They were followed by Ascaris lumbricoides and Trichuris trichiura at less than 3%. There were striking differences in prevalences and intensities of infection of the different helminthic parasites among the 15 communities surveyed. In general, differences between males and females were not statistically significant. Age-prevalence and age-intensity profiles for hookworms showed that infection increased with age, with a peak in the adult age groups. A. lumbricoides prevalence was relatively high in children but declined to a very low plateau in adults. There were no significant relationships between number of households per latrine at each community and the prevalence and intensity of infection by hookworms and prevalence of roundworms. The relevance of the above findings is discussed in relation to the control of morbidity and transmission of the helminths.