There are several reasons why there is no vaccine for malaria, but the thing you might want to know is that malaria is not a virus, and it is not even a bacterium. It’s a protist. Generally speaking, there are not really vaccines for such organisms. One metastudy that looked specifically at Malaria had this to report:
We identify and evaluate 1916 immunization studies between 1965-February 2010, and exclude partially or nonprotective results to find 177 completely protective immunization experiments. Detailed reexamination reveals an unexpectedly mundane basis for selective vaccine failure: live malaria parasites in the skin inhibit vaccine function. We next show published molecular and cellular data support a testable, novel model where parasite-host interactions in the skin induce malaria-specific regulatory T cells, and subvert early antigen-specific immunity to parasite-specific immunotolerance. This ensures infection and tolerance to reinfection. Exposure to Plasmodium-infected mosquito bites therefore systematically triggers immunosuppression of endemic vaccine-elicited responses. The extensive vaccine trial data solidly substantiate this model experimentally.
Crap, that’s bad news.
But wait, there may be a way to make a malaria vaccine anyway, and the latest reports from Britain are quite positive.
The long-awaited results of the largest-ever malaria vaccine study, involving 15,460 babies and small children, show that it could massively reduce the impact of the much-feared killer disease. Malaria takes nearly 800,000 lives every year – most of them children under five. It damages many more.
The vaccine has been in development for two decades – the brainchild of scientists at the UK drug company GlaxoSmithKline, which has promised to sell it at no more than a fraction over cost-price, with the excess being ploughed back into further tropical disease research.
“This data bring us to the cusp of having the world’s first malaria vaccine, which has the potential to significantly improve the outlook for children living in malaria endemic regions across Africa,” said GSK’s chief executive, Andrew Witty.
“The addition of a malaria vaccine to existing control interventions such as bed nets and insecticide spraying could potentially help prevent millions of cases of this debilitating disease. It could also reduce the burden on hospital services, freeing up much needed beds to treat other patients who often live in remote villages, with little or no access to healthcare.”