A new malaria vaccine, created by an Indian-origin scientist, targets the parasite at a vulnerable point in its development. This, hence, may form part of a strategy to eradicate the disease.
Unlike other vaccines in the pipeline, which are designed to protect individuals who have been bitten, this one aims to sabotage the life cycle of the malaria parasite, Plasmodium, by stopping it from passing back from humans to mosquitoes.
AdvertisementLead author Nirbhay Kumar, of Johns Hopkins Malaria Research Institute in Baltimore, Maryland, said that while preventing this transmission wouldn't help an infected individual directly, it would benefit the population as a whole.
"If you are living in a village and the mosquito that bites you gets infected from you, it can transmit the malaria parasite to other people in the village," New Scientist magazine quoted him as saying.
To create the vaccine, he and his colleagues used genetically modified bacteria to make proteins identical to some of those involved in the parasite's sexual development. They injected the proteins into mice and baboons, which generated antibodies.
When the researchers added Plasmodium gametes to blood samples from these animals, the antibodies bound to and blocked the proteins.
If a mosquito sucked up some of this blood, it would still get a bellyful of the gametes, but they would be unable to combine and spawn new adult parasites.
One shot of the vaccine led to a 93 per cent reduction in malaria transmission, and the figure went up to 98 per cent after a booster shot.
The new vaccine could be used alongside another vaccine being developed by GlaxoSmithKline, called RTS,S/AS02A, which blocks Plasmodium transmission from mosquitoes to humans.
By attacking the parasite's life cycle at two points, it may even be possible to wipe out malaria.
"If this vaccine is as promising in clinical trials as it has been in this study, then it may prove to be an important part of an integrated disease-control strategy aimed at eradicating Plasmodium," said Andrew Read of Pennsylvania State University in University Park, who works on the ecology of infectious diseases.
The study has been published in PLoS One.