A new malaria vaccine has been successfully tested on a small group of volunteers, U.S. researchers announced on Thursday. CNN reports that the vaccine, which involves multiple intravenous inoculations, kept a substantial percentage of test subjects from contracting the disease. The researchers hope to conduct a larger trial in the near future.

“These trial results are a promising first step in generating high-level protection against malaria, and they allow for future studies to optimize the dose, schedule and delivery route of the candidate vaccine," lead author Robert Seder, M.D., said in a press release. Seder is the chief of the Cellular Immunology Section of the NIAID Vaccine Research Center.

Malaria vaccine shows promise, but work remains

Health officials from the Navy, the Army, the National Institutes of Health, and other U.S. organizations note that although the new malaria vaccine shows great promise to quell the ravaging disease, a proof of concept and extensive field-testing still remain before it can be approved for public use.

"This is not a vaccine that's ready for travelers to the developing world anytime soon,” Dr. William Schaffer of Vanderbilt University’s medical school told CNN, noting that large-scale manufacturing and distribution could still be years away. "However, from the point of view of science dealing with one of the big three infectious causes of death around the world, it's a notable advance. And everybody will be holding their breath, watching to see whether this next trial works and how well it works."

The new malaria vaccine, formally known as PfSPZ Vaccine, is administered through multiple intravenous injections of a weakened form of the disease. The results of the small trial suggest that a higher dose corresponds to better protection; whereas 16 of 17 participants receiving low dosages contracted the disease, only three of the 15 participants receiving high dosages became infected.

Malaria kills about one million of the 200 million it sickens each year. According to the World Health Organization, approximately 90 percent of malaria deaths occur in sub-Saharan Africa. The main victims are children under the age of five.