In a first stage trial an new type of malaria vaccine, made from whole, irradiated sporozoites, has shown itself to be 100% effective. The vaccine, PfSPZ was developed by Sanaria and its lead researcher, Stephen Hoffman, a veteran malaria researcher. This work was encourages by research in the 1970s, showing that long-lived protection could be had by exposure to thousands of bites from irradiated, infectious mosquitoes. Taking this observation and making progress has been slow because it is very difficult to create the weakened sporozoites and make them safe enough to use in a vaccine.
The initial trial was encouraging, 6 of 6 patients who were given 5 doses of the vaccine were immune to subsequent challenges with the live parasite. In the control group, 5 of 6 not given the vaccine developed malaria, as did 3 of the 9 in a group that only received four doses. Larger trials are now scheduled and the method of delivery of the vaccine may make wide-spread use difficult. The vaccine has to be given intravenously, instead of orally or subcutaneously; the method all modern vaccines use. With more research, maybe these issues can be overcome. In any case, this is a giant step forward in treating a disease that causes the most harm to the most people worldwide.