[NAIROBI] Giving children antimalarial drugs three times before the age of one year could boost their immune systems enough to stop them getting the disease well into their second year, say researchers.
The team, led by David Schellenberg of the London School of Hygiene and Tropical Medicine, United Kingdom, gave the drug sulfadoxine-pyrimethamine to Tanzanian children who did not have malaria. The treatment cut the risk of malaria by 36 per cent compared to the risk in untreated children.
The research, published in The Lancet last week, showed that protection against malaria lasted much longer than could be explained by the effect of the drug alone.
This, say the researchers, suggests that as well as fighting the malaria parasite the drug boosted the ability of the children's immune system to fight the infection.
According to Schellenberg, researchers in Tanzania's Kisumu and Kilimanjaro regions are trying to identify other drugs that might be useful for this method of preventive treatment.
Schellenberg's study was conducted at the Ifakara Health Research and Development Centre, Tanzania.
The researchers gave half the children antimalarial drugs when they were immunised for childhood diseases such as polio and measles, at the ages of two, three and nine months. The remaining children were given a placebo.
Schellenberg says the findings highlight the need to enhance malaria control in young children because severe malaria threatens the lives of many African children under the age of one year.
The World Health Organization estimates that malaria accounts for 20 per cent of all childhood deaths in Africa.
However, scientists in neighbouring Kenya who have been using this type of preventive treatment only for pregnant mothers have called for more research to monitor possible unforeseen effects.
James Sekento of the Kenyan Ministry of Health's malaria control division, told SciDev.Net that the science underpinning the research seemed valid but he warned that 'overprotecting' infants at an early age could make them more susceptible to the disease when they get older.
Sekento notes that while aid donors recommend giving malaria drugs intermittently to protect children, Kenya says this is not necessary as it has other options for infant protection.
Kenya follows up its preventive treatment during pregnancy by providing insecticide treated nets from the time the child is born up until it is five years old, he added.
"We consider these preventive measures to be enough," said Sekento. "We simply don't want to transfer the vulnerability of an age group from infants to adults, which this research seems to ignore."
Increasing resistance of the malaria parasite to sulfadoxine-pyrimethamine means it is no longer the drug of choice in many regions in Africa. The World Health Organization now recommends using drug combinations containing artemisinin instead (see Artemisinin is now drug of choice, fund tells Africa).