An experimental malaria vaccine has shown promising results in early stage clinical trials, marking a victory that has long eluded science.

In an early-stage clinical trial, several volunteers were exposed to malaria.  Six of them received five doses of the so-named PfSPZ vaccine, and it protected all six from the malaria infection.  Another group of nine volunteers were each given a four-rose regimen; two-thirds of that group was protected. In contrast, five out of the six unvaccinated participants became infected with the disease.

The study, which appears in the journal Science, was extremely small and short-term.  And lead author Dr. Robert Seder, from the Vaccine Research Center at the National Institutes of Health, in Maryland, said the experimental vaccine still has a long way to go before it could be used in the developing world.

“We were excited and thrilled by the result,” Seder said, “But it is important that we repeat it, extend it and do it in larger numbers.”