The alert was issued by the Paris paediatric cardiology network, le Centre de Référence Malformations Cardiaque Congénitales Complexes (“M3C Necker”), to national health agency Santé Publique France.
It comes days after the UK National Health Service (NHS) issued the same warning, after around a dozen children in Britain were admitted to hospital with a high fever and arterial inflammation. The majority tested positive for Covid-19.
UK health minister Matt Hancock told newswire Reuters: “It’s a new disease that we think may be caused by coronavirus and the COVID-19 virus [but] we’re not 100% sure because some of the people who got it hadn’t tested positive, so we’re doing a lot of research now, but it is something that we’re worried about.”
In France, M3C Necker network coordinator, Dr. Damien Bonnet, told newspaper Midi Libre: “This inflammatory syndrome concerns the heart, the lungs, and/or the digestive system. The clinical state of some patients is reminiscent of Kawasaki disease.”
Kawasaki disease is a lymph node syndrome that mainly affects children under the age of five. It can cause symptoms including fever, skin rashes, swelling of glands; and in severe cases, inflammation of arteries of the heart.
It is rare, normally affecting only around eight in 100,000 children per year, and is more common in Asia.
In an alert to his colleagues, Dr. Bonnet said: “A growing number of children of all ages are being hospitalised in the context of multi-system inflammation that frequently includes circulatory [heart and blood vessel] failure with evidence of myocarditis [inflammation of the heart muscle].”
There have been 25 confirmed cases of the condition, requiring admission to intensive care, in the Paris area over the past three weeks, plus around a dozen admissions to the specialist Necker hospital.
Dr. Bonnet said that he is concerned that the condition is linked to Covid-19, but is only appearing now, promoting questions over the safety of the deconfinement schedule proposed this week by Prime Minister Edouard Philippe.
Dr. Bonnet said: “The epidemic started five weeks ago in Ile-de-France, and these young children have [only] been coming in over the past two weeks. There has been a spike [of cases] since Friday (April 24). This is a worrying phenomenon.
“The good news is that the patients improve very quickly. They are only in danger for a few hours.”
More cases have been confirmed in the UK and Spain, plus 10 confirmed patients in Belgium.
Newswire Reuters has also reported that doctors in northern Italy - one of the areas most affected by Covid-19 - have also seen a spike in “Kawasaki disease-like” cases among children aged nine and under.
There have been no deaths reported in France, but in the UK Mr Hancock suggested to LBC Radio that some children had “died who didn’t have underlying health conditions”. He did not give an exact figure or specify to which country he was referring.
In France, Dr. Bonnet added that doctors must be alert to the issue, and report all suspected cases. Any suspected patients must “see a cardiologist”.
Dr. Alexandre Belot, rheumatologist and paediatrician at the mother and children hospital in Lyon (Auvergne-Rhône-Alpes), told newspaper la Dépêche du Midi: “This is an alert that we are taking very seriously in France.”
‘We should not scare parents unnecessarily’
But Dr. Eric Jeziorski, head of general pediatrics, infectiology, immunology and clinical immunology at the CHU hospital in Montpellier (Hérault, Occitanie) said: “These events are very rare, for the moment. We're collecting data. We're not at all at the point of a worrying [widespread] health alert.”
He said: “Kawasaki disease is caused by an infection, so in theory it could be linked to the coronavirus [SARS-CoV-2, which causes Covid-19]. But today we have no proof of this.”
The Montpellier CHU is seeing an average of one such case per month. The two cases confirmed so far are now the subject of further investigation. The patients have so far not tested positive for Covid-19, and they are “doing well”.
Dr. Jeziorski said: “We must not scare parents [unnecessarily].”
UK health minister Mr Hancock added: “It is rare - although it is very significant for those children who do get it. The number of cases is small.”
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