An Australian woman who contracted malaria in Cambodia is seeking legal advice after her doctor advised against taking medication to prevent the disease.

Shelley Hill, from Byron Bay in northern New South Wales, is facing the amputation of her hands and toes after returning from the trip and falling ill.

Shelley Hill (L) and her friend Mel Wilson in happier times before Ms Hill was struck down with malaria. ( Supplied: Mel Wilson )

Ms Hill, 46, was recently transferred to the John Flynn Private Hospital on the Gold Coast after spending five days on life support in the nearby Tweed Hospital.

Her friend Mel Wilson spoke on Ms Hill's behalf because Ms Hill was too sick to be interviewed.

"We've got a solicitor on board, but she visited a GP and had certain vaccinations, but was told malaria was not required [because] it was the dry season," Ms Wilson said.

The Australian Department of Health advises travellers to seek advice from their doctors six to eight weeks before travelling to countries where infectious diseases pose risks.

The Government's Smart Traveller website advises people to take prophylaxis (preventative treatment) against malaria where necessary.

Malaria advice 'complicated'

Malaria expert Professor Ric Price, from the Menzies School of Health Research in Darwin, said advising travellers about the prevention of malaria was not straightforward.

"It's complicated and needs to be done with an informed interaction with the patient, because none of the drugs that we give are 100 per cent safe. They all have some side effects," he said.

"If the risk is extremely low, then the risk for the side effects can sometimes be greater than the risk of malaria."

Side effects vary depending on the medication, but can include nausea, blurred vision and neurological problems such as dizziness and anxiety.

Professor Price said a traveller would have to be extremely unlucky to contract malaria in Cambodia if they were visiting for a short time.

"Throughout most of Asia, malaria has gone down dramatically over the last 10 years," he said.

"In 2016 there were 83,000 cases of malaria and 140 deaths.

"With a population of 15 million people, that equates to about a 1 in 200 chance of getting malaria if you were there for a year, but if you were there for a two-week holiday, your chance would be about 1 in 5,000."

Professor Price said it was also important for doctors and travellers to assess the varying risks of different regions of particular countries, and the activities that would be undertaken.

"It depends on what you're doing. If you're sitting out at a cafe by a swamp and not wearing any repellent, you would be at far greater risk than someone sleeping in an air-conditioned room under a mosquito net," he said.

"No matter where you are going in that country there is a risk, and you can mitigate the risk sometimes with drugs, but they are not 100 per cent effective or protective or safe."

Shelley Hill is facing the amputation of both her hands after contracting malaria. ( Supplied: Mel Wilson )

'On life support within hours'

Ms Wilson said Ms Hill had travelled to Cambodia to volunteer at an elephant sanctuary for one week.

"When she got home she felt terribly ill and it went downhill from there," she said.

"She had really high fevers, shaking, vomiting, shivering and then she called a 1300 doctor number and they found out she had been to Cambodia, so they sent her for a blood test.

"The results came in and they rushed her straight to hospital, because they knew it was the most severe strain of malaria, and by the time she got to hospital she had to be carried in and was on life support within hours."

Ms Hill was taken off life support last week but still needs assistance with breathing, as well as daily dialysis because of liver and kidney damage.

Ms Wilson said it was necrosis (the death of cells in organs or tissue) in Ms Hill's hands and feet that was now doctors' primary concern.

"The symptoms are similar to meningococcal. The body is fighting so hard to survive that all the blood rushes to the vital organs and your extremities get cut off from blood and you get necrosis — so her fingers look black, like she has gangrene," Ms Wilson said.

"Surgeons are trying to give her as many days as possible to see if she gets some feeling back in her fingers or toes.

"It's just a wait and see. It just depends how much damage has been done."

Quick action needed

Professor Price said one of the most important tips he could offer was for travellers to be aware of disease symptoms and seek immediate treatment.

"The earliest signs of malaria are flu-like aches and pains in joints and a fever, and that can be a low-grade fever," he said.

"If malaria progresses, that's when you start having shakes and sweats and then you can have manifestations of severe disease where you lose consciousness and your lungs and kidneys stop working properly.

"It's very important as soon as you get early symptoms, and that can be as late as two months after your return from abroad, you should seek medical advice and go to your general practitioner and other doctor and let them know you've been in a malaria-endemic country and should be tested."