Malaria kills about 780,000 people a year, and most of them are children in Africa.
The Bill and Melinda Gates Foundation has made eradication of the disease a top priority. On Tuesday, the organization touted the results of a study that showed a vaccine developed by GlaxoSmithKline protected nearly 50 percent children from severe malaria.
From a medical perspective, the vaccine is not particularly successful, but cutting the rates of infection by malaria in half would save millions of lives.
But, Nathan Ford, medical director for Doctors Without Borders, said the risk of having a vaccine that works less than half of the time, is that donors will stop investing in the other measures that fight the spread of malaria, like bed nets, diagnosis and treatment.
"If this vaccine is rolled out and you get it, you're only partially protected," Ford said. "You still need to use those other things to be protected."
An integrated approach, with mass vaccinations for some populations, as well as bed netting and other tools, will still be necessary. Continuing to fund those other tools will be critical to keeping survival rates up, especially because there are other limitations to the vaccine, in addition to its efficacy.
On average, people can contract malaria as many as six times in a year.
"At the moment, it looks like it's not just a one-shot vaccine. It would need to be repeated," Ford said.
But, in reality, this is a good sign, Ford says. Often the big breakthrough is preceded by an incremental improvement, like this vaccine.