A vaccine for malaria is a step closer to reality after Melbourne researchers made a significant discovery about how the human body's immune system fights the infection.

Professor James Beeson from the Burnet Institute said although malaria was transmitted by mosquitoes, it was when the infection replicated in the body's red blood cells that it became harmful.

"The infection gets out of control and that eventually can cause severe disease and death," Professor Beeson said.

"So our question is, what does the immune system do or what can it do to block that infection and stop that process happening and stop people getting sick?"

He said the researchers had identified the body's immune system needed both antibodies and other proteins in the bloodstream to fight off malaria in what he called a "double-hit" effect.

"The immune system needs to produce specific antibodies and they're proteins that the immune system produces that combat infections," he said.

"Those antibodies recognise the malaria infection, or the parasites as we call them. And then they need to recruit these other proteins that are in the bloodstream, known as complement proteins.

"And then the two together, the antibodies and the complement, perform a double hit on the malaria infection and stop it from getting inside red blood cells, and therefore stopping the infection and the subsequent disease."

A number of malaria vaccines have been trialled over the years but Professor Beeson is hoping this discovery will bring a viable vaccine closer to reality.

"We're hoping that this new knowledge opens up a new strategy to generate or develop highly effective vaccines," he said.

"And so in fact in some of our work that we've done, we've now shown that people who have been immunised with these candidate vaccines, we call them experimental vaccines, vaccines that are in development, we found that at least in some individuals those vaccines can induce this antibody complement double-hit effect.

"So the step forward really is to say: how can we maximise that effect? How can we get high levels of antibodies and get the right type of antibodies that will recruit complement to maximise the protective effect of the vaccine?"

Professor Beeson said most of the 600,000 people who die of malaria each year were children and the need for a vaccine was becoming more urgent.

"Malaria infection is becoming resistant to drugs that we use to treat it. Additionally, the mosquitoes that transmit malaria are becoming resistant to the insecticides that we use to try and control them and get rid of mosquitoes," he said.

"So two of our important strategies for controlling malaria are at risk and it just further emphasises why the development of effective vaccines is really urgent."

The research has been published in the international journal Immunity.