As the parents of a previously healthy toddler mourn their "gentle soul" after her unexpected death from COVID-19, infectious diseases specialists have described such cases in children as "extremely rare".
Ruby Grace Edwards died in the Queensland Children's Hospital on Sunday, two weeks before her second birthday, after being diagnosed with COVID-19 and developing encephalitis, the medical term for inflammation of the brain.
Her parents, Krystal and Steven Edwards, said they felt as if "our world is falling apart" as they prepared for the birth of their son tomorrow.
"This is supposed to be such a happy time, where our family would become complete but is now so broken," Mr Edwards wrote on social media.
University of Sydney infectious diseases specialist Robert Booy said children with viral infections "can very rarely develop encephalitis".
"The encephalitis might be due to an inflammatory problem where the body is reacting to the virus, trying to fight it off and cross-reaction with the brain leads to damage," Professor Booy said.
"It may be that there's a rare genetic predisposition, a rare genetic problem, that has brought this on in combination with the COVID infection.
"Parents need to be aware that any viral infection can, rarely, be very serious in children.
"In the main, COVID is not a serious infection [for] children and the great majority will get over it very quickly."
Federal Health Department figures show 14 children aged under the age of 10 years have been classified as COVID-associated deaths among more than 420,000 known cases of the virus in that age group across the country.
Mr Edwards told the ABC that Ruby had tested positive for COVID-19 on July 14 after a "couple of days of fever".
They took her to Logan Hospital and she was allowed to go home after responding well to fluids.
"We again took her back to hospital when there was no improvement," Mr Edwards said.
"After receiving fluids and showing signs of improvement, we were expecting to take her home again.
"However, she experienced a seizure, prompting further investigation and was subsequently transferred to Queensland Children's Hospital (QCH) for neurological assessment."
Doctors at the QCH diagnosed her with acute haemorrhagic leukoencephalitis (AHLE), characterised by inflammation of the brain and spinal cord.
Although the exact cause was unclear, doctors said it usually followed a viral or bacterial infection.
'This happens to other people'
QCH infectious diseases specialist Adam Irwin said AHLE was "an extremely rare complication of COVID-19 infection".
"There have been very few cases in children reported worldwide," Dr Irwin said.
"Symptoms usually develop quickly. Features that may indicate serious disease include vomiting, seizures and a change of consciousness or behaviour."
Ruby's grieving dad said the family was "still in shock and disbelief, like it's not really happening to us".
"This happens to other people," Mr Edwards told the ABC.
"I don't want to propagate fear, but maybe caution and a reminder to cherish those you love because you just don't know when it can all be taken away."
He described Ruby as a gentle soul, who loved her cuddles and "was adored by all [who] were fortunate enough to meet her".
"Ruby had the most beautiful, long eyelashes, infectious smile and stunning hair colour," Mr Edwards said.
"She was very clever and had so much potential. Everyone would always comment on how advanced her speech was for her age.
"It's a shame that her full potential will never be realised, and the world has been deprived of such a special gift."
Ruby was too young to have been vaccinated against COVID-19.
Vaccinations coming for under fives
Australia's medicines regulator, the Therapeutic Goods Administration, last week provisionally approved Moderna's COVID-19 vaccine for children between six months and five years of age.
However, the Australian Technical Advisory Group on Immunisation (ATAGI) still needs to provide the federal government with recommendations on its use before children under five can be given access to a COVID-19 vaccine.
Professor Booy said he expected vaccinations in that age group to begin next month.
"I would prioritise children who have a chronic medical problem or a disability for vaccination first," he said.
"I would recommend that, if children are attending day care or preschool that — because they're at great risk of transmission — they be vaccinated and then, more generally, well children who are based at home might benefit from vaccination because, rarely, well children can get COVID severely.
"Almost certainly, all of the complications of COVID involving inflammation … are generally less common in vaccinated children."
