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
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
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
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.