/ 14 February 2008

Nutrients study bodes well for malaria efforts

Malaria continues to cut a swathe through Africa, which accounts for most cases of the disease and of malaria-related deaths. Globally, more than a million people die from malaria each year. In the case of children, this translates into a death every 30 seconds, according to the World Health Organisation.

A study by Burkina Faso’s Health Sciences Research Institute (IRSS) may point the way to reducing malaria’s toll on children, however.

IRSS research director Jean-Bosco Ouedraogo and his colleagues report in the current issue of Nutrition Journal that giving vitamin-A and zinc supplements to children has been shown to reduce the incidence of malaria among them by one-third. The journal is an online publication managed from London.

New ways of fighting malaria are critically needed. In recent years, the disease’s growing resistance to drugs and insecticides (malaria is transmitted by mosquitoes) has made malaria control much more challenging.

Ouedraogo spoke to Inter Press Service science correspondent Stephen Leahy.

What were you trying to discover in this study?

Malaria is the primary cause of death in Burkina Faso, and we were aware that both zinc and vitamin-A supplements had been effective individually in reducing malaria in Papua New Guinea. Vitamin A and zinc are crucial for normal immune function, and we wondered if the combination would act synergistically and reduce the risk of infection.

How did you conduct the study?

We recruited 148 children aged from six to 72 months of age in the village of Sourkoudougou, about 25km from Bobo-Dioulasso [south-western Burkina Faso]. Half of the children received daily zinc supplements and a single dose of vitamin A, and the other half received a placebo.

The children were then examined daily for a period of six months. If they had a fever, a blood sample was taken to see if the malaria parasite was present.

Can you comment on your results?

We were expecting a 10% decline, but were surprised that the prevalence of malaria declined by 34% in the group receiving supplements compared to the group receiving placebos. Anaemia also declined significantly in the supplemented group, from 18% to 5,4%.

Were the children lacking zinc and vitamin A in their diets?

Zinc deficiency probably exists in Burkina as it does in other African countries such as Ghana, but there have been no studies here. Zinc is required for vitamin A to be metabolised in the body. Both micronutrients are essential for immune systems to function normally.

What have you concluded from this study?

Vitamin A and zinc should be an essential part of malarial control strategies. Improvements in anaemia also reduced the incidence of fever and other disease. While vitamin-A supplementation [is being provided] with the expanded programmes of immunisation campaigns as recommended by Unicef [the United Nations Children’s Fund], these [programmes] have not taken zinc supplementation into consideration — with the exception of diarrhoea-treatment programmes.

Our findings suggest that dual supplementation with vitamin A and zinc is effective against malaria, and that a longer supplementation period might lead us to observe more important beneficial effects.

Do you envision a programme that distributes zinc and vitamin-A tablets?

The more affordable and sustainable solution would be the incorporation of vitamin A and zinc in food fortification for children. It is important to find natural sources of these micronutrients and incorporate them into people’s diets. Changing food habits — such as switching from white maize to yellow maize, which contains more vitamin A — is a better approach than distributing tablets. We have a project under way to encourage the planting of yellow potatoes for the same reason. Carrots and mangos are also high in vitamin A and we are looking at fortifying cooking oil as well.

What about zinc?

It is important to find natural sources of zinc. We have just received some new equipment that will allow us to measure the zinc content of various foods.

Are your findings applicable to other African countries?

We have received funding from the International Atomic Energy Agency [IAEA] in Vienna to do a large regional study in Cameroon, Ghana and Mali to confirm our findings from Burkina.

Why is the IAEA funding you?

The IAEA has a health and nutrition research division under its “Atoms for Peace” mandate. Stable (non-radioactive) isotopes are used to make measurements. [Stable isotopes are commonly used in nutrition studies to gauge various levels of nutrients in blood.]

Do you think these micronutrients can effectively reduce the incidence of malaria in Africa?

It is a very exciting possibility.

— IPS