SOMETHING was wrong with Eva Cary when she woke at 4am in February with a terrible headache.

It was so bad she vomited. The headache persisted for two days which prompted Eva, 63, to go to a doctor at Calliope for scans but they revealed nothing.

But this dedicated and devoted mum still managed to mow the lawn that day.

CLOSURE: Casey, Owen, 7 months, Bill and Andrew Cary with Hazel, 3. Paul Braven

But Mr Cary noticed things still weren't quite right when his wife of more than 40 years started cooking dinner and forgot halfway through what she was doing.

Eva then went and laid down on her bed but despite her telling her husband she was okay, Mr Cary called the ambulance.

"Things went downhill very rapidly and when the ambulance turned up she couldn't say her name," he said.

Eva was taken to Gladstone Hospital where staff ordered more scans but once again nothing appeared and Mr Cary said doctors thought Eva had suffered a stroke and sent her to Rockhampton.

On the way there Eva had a seizure and when she presented at the hospital she was given more scans, which Mr Cary said doctors determined revealed a tumour.

As soon as a bed become available and a CareFlight was organised, Eva was flown down to the Royal Brisbane and Women's Hospital where surgeons operated on her to remove the tumour.

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However, during the operation the suspected tumour turned out to be "dead brain matter" which Mr Cary said made doctors revert back to their original inkling that Eva had had a stroke.

"After the operation Eva was in the recovery ward for less than 24 hours and because she'd come out of it and was talking and seemed okay, we thought we'd all be able to go home," Mr Cary said. "A week later she was complaining of a tingling feeling in her arm (and) she had another seizure."

Unfortunately from this moment Eva never regained consciousness and doctors put the cause of death as a stroke.

But this was wrong and what nobody knew at the time, as well as for the days leading up to the time of Eva's death, was that somehow she had contracted a rare soil-borne parasitic amoeba, which was eating away at her brain.

"Her brain was being destroyed by this amoeba and this was happening all the time but they didn't know it," Mr Cary said.

The amoeba, Balamuthia mandrillaris, has reportedly been responsible for only five deaths in Australia. Eva is believed to be the eighth Australian to ever contract the potentially deadly amoeba.

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According to the Centre for Disease Control and Prevention, the amoeba is thought to enter the body and infect the brain and spinal cord after it comes in contact with skin wounds and cuts or "when dust containing Balamuthia is breathed in or gets in the mouth".

Looking for closure and feeling unconvinced about Eva's cause of death, the Cary family ordered a post-mortem which showed the true cause to be Balamuthia.

"The concern was that they didn't know if it was cancer or a stroke," Eva's daughter-in-law Casey said. "Even when they operated they didn't know what it was."

If the Cary family hadn't felt the hospital had missed something then they would have never known, which Eva's only son Andrew said was comforting.

"(The post-mortem) was never going to bring mum back but at the end of the day it has given us an answer and we won't be left wondering if more could have been done," Eva's only son Andrew said.

As a result of the post-mortem Eva will be issued with a new death certificate and next month a seminar in Brisbane will be held using Eva's death as a case study to increase awareness about the rare and deadly amoeba.

And although the family has no idea how Eva contracted the parasitic amoeba, Mr Cary said it may be rare but "it's out there and people need to be warned like they are about meningococcal".

Since Eva's death Mr Cary said he was "managing" but all it took was a photo to bring the memories and tears flooding back.

"When your wife dies you lose half of your life," he said.

The couple married in 1973 but if it wasn't for a sneaky note passed by one of Eva's friends in church to Mr Cary, the two may never have been able to raise five wonderful kids.