Joy E. M Callender

School performance, nutritional status and trichuriasis in Jamaican schoolchildren

Severe infections by the geohelminth Trichuris trichiura detrimentally affect young childrens growth and development. There is concern that mild to moderate infections may affect older childrens school performance and nutritional status. We therefore examined the relationship between varying intensities of infection and school achievement, attendance and nutritional status in 616 schoolchildren. A total of 409 children with Trichuris infection of intensities greater than 1200 eggs per gram of stool (epg) were first identified, then for every 2 infected children in a class, an uninfected child was selected. After controlling for socioeconomic status, gender, age, school and the presence of Ascaris infections, the uninfected children had higher reading and arithmetic scores than children with infections of more than 4000 epg and were taller than those with intensities greater than 2000 epg. However, there were no significant differences in spelling, school attendance and body mass index. Although a treatment trial is needed to determine causation, these results indicate that moderate levels of infection are associated with poor school achievement and growth.

Treatment effects in Trichuris dysentery syndrome

Heavy infection with the geohelminth Trichuris trichiura causes the Trichuris dysentery syndrome (TDS). Growth retardation and anaemia are characteristic of TDS and both are associated with poor development. We have examined the growth and developmental responses to treatment in 19 children aged 27–84 months with TDS. Developmental levels (DQ) were measured with the Griffiths mental development scales. Compared with a control group matched for age, gender and neighbourhood, the TDS children initially had serious deficits in DQ (24 points, p < 0.001). After a year of anthelmintic treatment, the TDS children showed improvement in locomotor development (p < 0.001) compared with the controls. The TDS children also had initial deficits in height‐for‐age, weight‐for‐height, mid‐upper arm circumference and haemoglobin levels. They caught up rapidly in indices of wasting (weight‐for‐height and mid‐upper arm circumference) and showed steady improvement in height‐for‐age and haemoglobin levels. Catch‐up in height was comparable to that of children recovering from coeliac disease. The importance of continuing prevention after initial treatment is highlighted.

Growth and development four years after treatment for the Trichuris dysentery syndrome

A follow‐up study is reported of 18 children 4 y after treatment for the Trichuris dysentery syndrome (TDS) and matched control children. The TDS children were initially severely stunted and had extremely low developmental levels. They showed catch‐up in height of 1.9 z‐scores even though they remained in very poor environments. Their intelligence quotients, school achievement and cognitive function remained significantly lower than those of the controls. Controlling for their earlier developmental levels, the TDS children showed a small improvement in mental development relative to the controls.