Australian researchers have captured on video the moment a malaria parasite tries to invade a red blood cell — the key point when a person becomes sick with the disease.

Key points: Oxford scientists identified two antibodies that work to stop malaria getting into red blood cells

Australian researchers confirmed the findings using microscopy to film the antibodies at work

It is a major step on the way to a vaccine, but it could still be a decade until one is available

The video, recorded by Victoria's Burnet Institute, then shows two antibodies repelling the parasites, which helped Oxford scientists solve a mystery.

The UK researchers needed to know how the two types of human antibodies were working together to fight the malaria parasite.

Oxford University molecular parasitologist Matt Higgins said Australian researchers played a crucial role.

"What we'd done in Oxford is we'd identified all of these different antibodies and we'd shown how they worked and we'd identified the best ones, but we were left with this mystery," he said.

"This mystery was how this particular group of antibodies, without being protected themselves, were able to make [other] protective antibodies better.

"We had a hypothesis, which was that they were slowing down the invasion process, but we didn't have any evidence."

The Burnet Institute researchers were able to capture on video what took place during that invasion process and confirm their hypothesis.

The Australian video proved the protective antibodies slowed the invasion by targeting the parasites' "Achilles heel".

A possible end to malaria tablets for travellers

The findings have been published in the journal Cell and are a promising sign for a potential vaccine.

Malaria facts: Malaria affects nearly 220 million people globally each year

Malaria affects nearly 220 million people globally each year More than 435,000 people died from malaria around the world in 2017

More than 435,000 people died from malaria around the world in 2017 Africa is home to 92 per cent of cases and a similar proportion of deaths

The development may mean that within a decade travellers taking malaria tablets could replace them with an injection.

Significantly, it could also offer a possible solution to a major global public health problem.

Malaria parasites are spread by mosquitos and infect more than 200 million people around the world each year.

Researchers said the vaccine under development could be crucial because it targets the parasite when it tries to invade red blood cells, which is when the parasite multiplies and makes people sick.

Prior to this, other vaccines being developed or available have targeted the disease when it first enters body and infects the liver. To date, have only been about 40 per cent effective.

The Burnet Institute in Melbourne is focused on improving the health of vulnerable communities in Australia and abroad, and was chosen to help because of its expertise in preparing and filming the malaria parasite using video microscopy.

Burnet Institute head of cell imaging Paul Gilson said, for scientists, malaria was a tricky parasite to target because it was "always one step ahead".

"Controlling parasites with the vaccine is quite difficult because the parasites have a number of tricks up their sleeve," he said.

"The first thing is that they escape from one red blood cell and invade a new red blood cell very quickly.

"So that doesn't give the immune system, and its antibodies, much time to combat the parasite."

But its "Achilles heel", Dr Gilson said, was that even as it multiplied, it retained a key protein, which was the one researchers were targeting with the antibodies.

Solving the mystery

In the study, the Oxford researchers vaccinated people for the protein RH5 and then the Burnet researchers filmed two kinds of antibodies from this vaccine in a test tube working together to stop the parasite invading red blood cells.

One antibody slowed down the parasite's invasion into the red blood cell from about 20 seconds to 1 minute.

That gave the second antibody time to bind with the malaria parasite and prevent it infecting the blood cell altogether, and in the process the second antibody became 10 times more effective.

"Once we got this initial result, they got very excited because it proved the hypothesis," Dr Gilson said.

But he said it could still be a decade before people were able to throw away their malaria tablets.

"It might take several years for them to produce the desired immune response and, of course, then the vaccine will have to undergo clinical trials and field trials to make sure that it's safe," Dr Gilson said.

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Burnet Institute researcher Rasika Kumarasingha had malaria twice as a child and is now helping to work on a vaccine. ( ABC News: Patrick Stone )

One of the scientists working tirelessly on the project was post-doctorate researcher Rasika Kumarasingha.

She was born in Sri Lanka and first had malaria at age four and again when she was about six.

"You have these alternating bouts of being hot and shivers, then vomiting and you can't eat," Dr Kumarasingha said.

"Then while you're getting better you feel this general weakness for months.

"It is actually called Jungle Fever and a lot of people suffered from malaria in the dry zone area of the country."

She went on to become a veterinary surgeon, but her experiences as a little girl inspired her to specialise as an infectious disease researcher.

"Having that background, research in malaria is close to my heart," she said.

Rasika Kumarasingha when she was a little girl in Sri Lanka about the time she got sick with malaria. She is pictured second from left with her family. ( Supplied )

It was Dr Kumarasingha's role to painstakingly mix the malaria and red blood cells in a lab and treat it with antibodies supplied by Oxford academics over the course of a year.

"We had to try different methods, different combinations to get this right," she said.

"Then when I analysed the data, it was so exciting and very intriguing."

Dr Kumarasingha had to check on the experiments every two days, filming what took place before she and Dr Gilson analysed the footage and data.

"I thought that 'we are witnessing something amazing' and we thought that this could actually change the game of vaccine development," she said.

"It's a big deal and it's revolutionary actually."

Researchers think the discovery of the synergistic way antibodies work together could be used for treatments for malaria and to help develop vaccines for other diseases.

In 2016, Sri Lanka was declared malaria-free and Dr Kumarasingha said she hoped her work would soon help rid the rest of the world of the disease.