Age-related prevalence and intensity of Trichuris trichiura infection in a St. Lucian community

• Published in: Transactions of the Royal Society of Tropical Medicine and Hygiene Vol. 81; no. 1; pp. 85 - 94
• Main Authors: Bundy, D.A.P., Cooper, E.S., Thompson, D.E., Anderson, R.M., Didier, J.M.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1987; Royal Society of Tropical Medicine and Hygiene; Elsevier
• Subjects: Adolescent; Adult; Age Factors; Aged; Animals; Biological and medical sciences; Child; Child, Preschool; Diseases caused by nematodes; Feces - parasitology; Fertility; Helminthic diseases; Humans; Infectious diseases; Medical sciences; Middle Aged; Parasite Egg Count; Parasitic diseases; Prevention and actions; Public health. Hygiene; Public health. Hygiene-occupational medicine; Sex Factors; Specific populations (family, woman, child, elderly...); Trichuriasis; Trichuriasis - epidemiology; Trichuris - physiology; Tropical medicine; West Indies; West Indies; Human; Infection; Trichuriasis; Nematod disease; St Lucian; Helminthiasis; Child; Epidemiology
• ISSN: 0035-9203; 1878-3503
• DOI: 10.1016/0035-9203(87)90293-8

Age-related changes in the average worm burden and the prevalence of Trichuris trichiura infection, in a village community in St. Lucia, were examined by field studies based on worm expulsion techniques. Horizontal age-intensity profiles were convex in form with peak parasite loads occurring in the 2 to 15-year-old children. Prevalence is shown to be a poor indicator of changes in average worm load with age. Faecal egg counts (epg and epd) provide a qualitative measure of worm burdens since fecundity is shown to be approximately independent of worm load. The parasites were highly aggregated within the study community, with most people harbouring low burdens while a few individuals harboured very heavy burdens. Of the total parasite populations in the study sample, 84% were harboured by the 2 to 15-year-old children. Of those individuals harbouring 100 worms or more, 87% were in the 2 to 10-year-old age range. Crude estimates of population parameters (basic reproductive rate, 4–5; rate of reinfection, 90 year −1) suggest that the rate of reinfection is higher than for other helminth parasites of man. The control of morbidity and parasite transmission is discussed in the context of targeting drug treatment at the child segment of the study population.