Iron status of schoolchildren with varying intensities of Trichuris trichiura infection.

The relationship between varying intensities of Trichuris trichiura infection and iron status was examined in Jamaican schoolchildren, aged 7 to 11 years. A total of 409 children was identified with T. trichiura (epg > 1200). A control group comprised 207 uninfected children who were matched by school and class to every pair of infected subjects. Blood samples were obtained from 421 children: 264 infected and 157 controls. Compared to the rest of the children, those with heavy infections (epg > 10,000) had significantly lower (P < 0.05) Hb (11.5 +/- 1.3 vs. 12.1 +/- 1.1 g/dl), MCV (78.6 +/- 6.3 vs. 81.2 +/- 5.5 fl), MCH (26.2 +/- 2.9 vs. 27.5 +/- 2.5 pg) and MCHC (33.2 +/- 1.5 vs. 33.9 +/- 1.4 g/dl). Similarly, the prevalence of anaemia (Hb < 11.0 g/dl) amongst heavily infected children (33%) was significantly higher (P < 0.05) than the rest of the sample (11%). These differences remained significant after controlling for confounding variables including socio-economic status, age, gender, area of residence and the presence of Ascaris infections. Differences in red cell count, ferritin, and free erythrocyte protoporphyrin were not statistically significant and showed no association with the infectious load. These results suggest that in the Jamaican children studied, iron deficiency anemia is associated with Trichuris infections over 10,000 epg, but not with less intense infections.