london an investigational malaria vaccine has been found to be 100 effective in protecting all adults who received it it also caused no side effect and has rekindled hopes for an effective vaccine against the vectorborne disease malaria affects halfabillion people killing three million each year and a child every 30 seconds around the world scientists called the earlystage clinical tests as the most promising yet in the global war on the worlds biggest killer although the proof of concept trial is small involving 40 adults it could pave the way for the first vaccine offering 100 protection known as pfspz vaccine the clinical evaluation was conducted by researchers at the national institute of allergy and infectious diseases niaid hopes of an effective malaria vaccine were dashed after the worlds most advanced candidate rts s that was to be available as early as 2015 failed to live up to its promise scientists found in march that its effectiveness waned over time with the shot protecting only 168 of children for as long as four years the latest vaccine has been found to be highly effective in generating an immune system response offering substantial protection against malaria infection in healthy adults nih vaccine researchers published results of earlystage clinical trial on friday in the journal science malaria is transmitted to humans by the bite of an infected mosquito after the bite infectious malarial parasites in the immature sporozoite stage of their life cycle first travel to the liver where they multiply and then spread through the bloodstream at which time symptoms develop a number of followup studies are planned including research to evaluate the vaccines different dose schedules possible protection against other plasmodium strains and the durability of protection the researchers may also evaluate whether higher doses administered subcutaneously or intradermally provide the same level of protection