School-based de-worming in Tanzania reduces severe anaemia

 

Tanzania prevents iron- deficiency anaemia in mothers and children in Zanzibar

In Zanzibar, Tanzania, a school-based de-worming programme has had a dramatic impact on children's health and development. Among the children involved, regular low-cost treatment has led to an increase in height and weight, a reduction in the prevalence of severe anaemia, and improved nutritional status.

Intestinal worms (helminths) are one of the most common infections on earth. Over a billion people are infected and twice as many are at risk. But the devastating impact of intestinal worms on health -- especially among pregnant women and school-age children -- is often underestimated.

At least 400 million children of school-age are chronically infected with intestinal worms -- mainly roundworms, hookworms, and whipworms. Infection leads to malnutrition, iron-deficiency anaemia, stunted growth, and increased vulnerability to other infections. And it has a serious impact on children's cognitive development -- affecting concentration and work capacity and increasing absenteeism from school.

Meanwhile, intestinal worm infections can be life-threatening for pregnant women and babies. Over 44 million women are infected with hookworms, which cause intestinal blood loss and iron-deficiency anaemia -- increasing the risk of premature birth and low birthweight babies. Chronic infection with intestinal worms holds back child development and limits educational achievement. It endangers reproductive health and affects adult productivity. And it undermines social and economic development.

Intestinal worm infections are most frequent among the poor. The soil-transmitted infections occur wherever living conditions and hygiene are poor and where access to clean water and sanitation is inadequate. Yet treatment is easy to administer and highly cost-effective, even in the poorest countries. Regular treatment two or three times a year with one of several recommended drugs from the WHO essential drugs list costs as little as US$ 0.09 (9 cents) a year.

In Zanzibar, Tanzania, a school-based treatment programme for intestinal worms has shown that regular de-worming of schoolchildren can increase their height and weight, improve iron stores, and reduce iron-deficiency anaemia.

Before the National Helminth Control Programme was started in 1994, almost every child in Zanzibar (99.7%) was infected with intestinal worms and malnutrition was widespread. By early puberty, over 60% of children showed signs of stunted growth and over 50% had iron-deficiency anaemia.

In 1994, a new de-worming programme was launched by the National Helminth Control Programme for about 30 000 primary school children on the island of Pemba, the smaller of the two islands that make up Zanzibar. The children were treated at school three times a year with mebendazole (an anthelminthic drug) in the form of chewable orange-flavoured tablets. Throughout the first year, the children had regular check-ups to monitor changes in the intensity of infection and to study the impact of treatment on their health status.

The results were impressive. Although roundworm infections responded best to the treatment, the intensity of all worm infections was reduced. By the end of the first year, the programme had prevented over 1200 cases of moderate to severe anaemia, and over 270 cases of severe anaemia.

By 1996, the prevalence of severe anaemia had been reduced by almost 40%, iron deficiency fell by 20%, and there was a marked improvement in the nutritional status of the children. The programme has since been extended throughout Zanzibar and now also targets pre-school children, and women of childbearing age, as well as school-aged children outside the formal education sector. Meanwhile, efforts are still under way to measure the impact the school-based programme has had on improving the cognitive development of the children involved.