TRICHURIS-TRICHIURA INFECTION AND COGNITIVE FUNCTION IN JAMAICAN SCHOOL-CHILDREN

Trichuris trichiura is extremely prevalent worldwide and there is conc ern that this geohelminth may affect the cognitive function of childre n in developing countries. A random-controlled, double-blind, treatmen t trial was conducted in Jamaican children with light to moderate infe ctions. This was part of a research programme involving several studie s in Jamaica. Ninety-seven subjects, each with a minimum of 1200 T. tr ichiura eggs/g faeces, were randomly assigned to placebo (N=48) or tre atment (N=49) groups. Each pair of infected children was matched with an uninfected classmate (N=48). All children mere given seven cognitiv e function tests: French-learning; digit spans (forwards and backwards ), Corsi block span; fluency; picture search; and silly sentences. Alb endazole was given to the treatment group and the other groups receive d a placebo. Three months later, these treatments were repeated, and t he cognitive function battery was as given again. On pre-test, the inf ected groups performed significantly poorer only in the silly-sentence test (analysis of variance F-value=8.17; two degrees of freedom; P<0. 001). There mas no significant improvement with treatment in any of th e tests. Taking into account these findings and those of the other Jam aican studies, it is therefore probable that light to moderate Trichur is infections have little effect on cognitive functioning in school ch ildren who have adequate nutritional status.