Malaria vaccine development: persistent challenges.

There is no licensed vaccine against any human parasitic disease and apicomplexan parasites cause enormous human suffering; the malaria parasite alone kills approximately one million people annually and is the cause of the majority of infection-related deaths in the young. A malaria vaccine is essential if the goal of malaria eradication is to be achieved. Decades ago it was shown that attenuated malaria parasites could induce sterile immunity to infection but progress towards efficacious vaccines for malaria has been slow. However, recent studies have begun to tease out the immune correlates of vaccine-induced sterile protection and essential research on animal models of disease continues to guide vaccine design. Whole parasite approaches to vaccine design through attenuation as well as subunit vaccine development continue to move forward to clinical trials and are showing promising results.