Doctors in Britain’s National Health Service have been sent an urgent alert warning of a rise in children admitted to intensive care with a coronavirus-related condition.

Medics have been warned of an apparent spike in cases of youngsters suffering with an "inflammatory syndrome" in the last few weeks.

The Paediatric Intensive Care Society said that the unidentified condition requires intensive care – with cases reported across the UK.

They say the syndrome has the characteristics of serious COVID-19, while abdominal pain and gastrointestinal symptoms, like vomiting and diarrhoea have also been seen by doctors.

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Doctors also warned the cases have features of toxic shock syndrome and atypical Kawasaki disease, an inflammatory condition that attacks blood vessels and the heart.

These conditions can cause harmful internal swelling, fever and breathing problems – which are all also the main symptoms of coronavirus.

But as it appears to be a completely new condition, the exact warning signs are unclear.

UK Health Secretary Matt Hancock called the condition “very worrying”.

In the alert, sent to GPs in North London, health chiefs said: “There is growing concern that a (COVID-19) related inflammatory syndrome is emerging in children in the UK.

“Over the last three weeks, there has been an apparent rise in the number of children of all ages presenting with a multi-system inflammatory state requiring intensive care across London and also in other regions of the UK.”

*Urgent alert*



Rising no of cases presenting to #PedsICU with multi-system hyperinflammatory state, overlapping features of toxic shock syndrome & atypical Kawasaki disease, bloods consistent with severe #COVID19 - seen in both #SARSCoV2 PCR +ve AND -ve



Please share widely pic.twitter.com/Bj6YHLJ8zi — PICSUK (@PICSociety) April 26, 2020

So far, the number of children affected has been small in the UK – and mostly in London – but senior paediatricians are concerned.

Some of the children have tested positive for the bug and some appear to have had the virus in the past, but some haven't had the bug at all.

The “urgent alert”, seen by the Health Service Journal, was issued on Sunday night by the Paediatric Intensive Care Society.

It stated: “Please refer children presenting with these symptoms as a matter of urgency.”

Paediatricians and GPs are being advised to refer children with symptoms urgently to paediatric infectious disease experts and intensive care doctors.

As yet, there have been relatively few serious cases of COVID-19 in children.

That doesn't mean that kids can't catch the virus – in fact, the youngest known case in the UK was only 30 hours old.

But based on the limited information available, the symptoms in children appear to be mild, or they may even be asymptomatic.

Experts warn for that reason that children may be "superspreaders" of the virus.

A study in the New England Journal of Medicine also said that "children might be less likely to become infected or, if infected, may show milder symptoms" than adults.

Symptoms may appear similar to other respiratory illnesses, such as the flu and the common cold, but COVID-19 is said to more likely to trigger a cough and fever, researchers said.

Experts say it's unclear why COVID-19 isn't impacting children as much as adults.

Especially because children's immune systems aren't as robust as adults and they tend to overreact.

Dr Nathalie MacDermott, from King's College London, told the BBC: "You'd expect it to go haywire and it's not doing that.

"There must be something this virus does that is not as readily stimulating the immune system in children, but what that is unclear.

"They don't seem to be mounting a disproportionate immune response and some seem to be asymptomatic."

This article originally appeared in The Sun and was reproduced with permission.