A malaria vaccine could be an important addition to current control strategies. We report the safety and vaccine efficacy (VE) of the RTS,S/AS01 vaccine during 18 mo following vaccination at 11 African sites with varying malaria transmission.
Every year, more than 200 million cases of malaria occur worldwide, and more than 600,000 people, mainly children living in sub-Saharan Africa, die from this parasitic disease. Malaria parasites are transmitted to people through the bites of infected night-flying mosquitoes and cause fever that needs to be treated promptly with anti-malarial drugs to prevent anemia (a reduction in red blood cell numbers) and life-threatening organ damage. Malaria transmission can be prevented by using long-lasting insecticides sprayed on the indoor walls of homes to kill the mosquitoes that spread the malaria parasite or by sleeping under insecticide-treated nets to avoid mosquito bites and further reduce mosquito numbers. Widespread use of these preventative measures, together with the introduction of artemisinin combination therapy (an effective anti-malarial treatment), has reduced the global burden of malaria by 45% in all age groups, and by 51% among young children, since 2000.