Malaria vaccine will it get to Nigeria...

Research published today (FRI) online in The Lancet Infectious Diseases indicates that the vaccine reduces the risk of infection by the parasite that causes severe malaria by 46 per cent over 15 months.

Malaria, which is passed to humans via infected mosquitoes, is one of the biggest killers of children in Africa.

Of the 900,000 people killed by the disease across the continent every year, the majority are children under five.

While the vaccine does not give near total protection, as those for other diseases marketed for use in Western countries typically do, it still has the potential to save large numbers of lives.

In the phase II clinical trial, 447 children from Kenya and Tanzania, aged five to 17 months, were given the RTS,S/AS01E vaccine, while the same number were given the rabies vaccine as a 'control' group.After 15 months, those who had the malaria vaccine were 46 per cent less likely to have been infected with the P Falciparum parasite than the control group. Only 11.4 per cent of those given the vaccine developed clinical malaria, compared to 19.7 per cent of the other group.

Dr Ally Olotu from the Kenya Medical Research Institute-Wellcome Trust Research Programme, who led the study, and fellow authors, concluded that the vaccine provides "sustained efficacy for at least 15 months and shows promise as a potential public health intervention against childhood malaria in malaria endemic countries".

The vaccine works by attacking the parasite when it first enters the bloodstream or liver cells, with the aim of completely preventing infection of red blood cells.

In 2008 results of a small-scale preliminary trial showed that it gave protection to 53 per cent of those vaccinated after eight months. However, the new study is larger, and shows only a small drop in the protection given after a further seven months.

The authors said more work was needed to see how well it worked in HIV-positive and malnourished children.

P falciparum is one of four species of malaria parasite that affect humans. It is found globally but is most common in Africa. It is the only one of the four species that can cause life-threatening malaria, according to the Wellcome Trust.