In the UK, where COVID-19 has killed more than 20,000 people, a mystery illness in children is now causing further concern.(AP: Matt Dunham)
The discovery of a potential link between an inflammatory condition in children and coronavirus has important implications for developing an effective vaccine, Australian scientists say.
An urgent alert in Britain warned doctors of the Kawasaki disease-like condition in children
Some children with the condition also had COVID-19, but a definitive link has not been confirmed
There is evidence some COVID-19 patients deteriorate after a week because of the disease's effect on blood vessels
British health authorities reported as many as 12 children, some of whom tested positive to COVID-19, were seriously ill in hospital with severe inflammation in the body.
It prompted Britain's National Health Service to issue an alert warning that the condition could be related to COVID-19 in children, or that there "may be another as-yet-unidentified infectious pathogen associated with these cases".
The children had symptoms similar to toxic shock syndrome and a condition known as Kawasaki disease, where kids experience abdominal pain, gastrointestinal symptoms and cardiac inflammation.
ANU professor Peter Collignon, an infectious disease physician and microbiologist, said scientists needed to know more about why kids under 15 got the mystery inflammatory condition and whether there was a link with COVID-19.
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"We do need to study these children because we still don't understand why children seem to get this [COVID-19] infection so much less than adults, but also why some people are getting these unusual reactions," he said.
Professor Collignon said understanding what was going on in children was vital in the quest to find a vaccine that would work well for all ages.
"We have to learn from places [like the UK], where it's more common, and use the information to make the best and most effective vaccines that are both safe and work."
Of the small number of children infected with COVID-19, most are believed to have contracted it from adults in their own household.
As the number of people infected with COVID-19 continues to fall in Australia, it is even less likely kids will get the illness.
A disease of the blood vessels?
As coronavirus spreads around the world, more is being learnt about how the disease works.
Leading Australian paediatric infectious diseases expert David Burgner, from Murdoch Children's Research Institute, said COVID-19 seemed to affect the blood vessels as much as it affected the respiratory system.
"There are increasing reports that the illness we are seeing in adults, the sudden deterioration after one week, is due to changes in the blood vessels rather than changes in the lung," Dr Burgner said.
"The changes we are hearing about from the UK, which are typical of Kawasaki disease and toxic shock, those are illnesses that predominantly affect the blood vessels.
"That's in keeping with our evolving understanding of what COVID-19 can do."
The National Medical Director for England, Stephen Powis, said it was too early to confirm a definitive link between COVID-19 and Kawasaki disease.
"We are not sure at the moment," he said.
"But our advice to parents is that these are the sort of diseases [that are] very, very rare."
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England's Chief Medical Officer, Chris Whitty, said it was "entirely plausible" that the severe inflammatory disease was caused by coronavirus in some cases.
"We know that in adults … there's big problems that are caused by an inflammatory process," he said.
"Given that, we've got a new presentation with a new disease."
Doctors in northern Italy have also reported children under the age of 10 being affected by what appeared to be Kawasaki disease.
Dr Burgner said parents should not be overly worried.
"These are rare conditions so the risk to an individual child is low, so we can be reassuring about that," he said.
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