One baby has died and eight admitted to intensive care in a mysterious cluster of infections thought to be caused by a typically-harmless virus.
In total, 15 newborns in Wales and southwest England have been struck down with severe myocarditis — inflammation of the heart — since June 2022.
One of them is still in hospital, according to an alert issued last night by the World Health Organization.
Health chiefs were spooked by the ‘unusual’ spike in cases over such a short space of time, prompting a thorough investigation.
Nine of the cases tested positive for a type of enterovirus, which usually causes no symptoms or just a flu-cold like virus.
However, experts are baffled as to what has caused the sudden spike. Health chiefs in Wales are probing the reasons behind the cases and will investigate any further cases that are reported in the coming weeks.
Enteroviruses usually cause only mild illness but tend to affect newborns and young children more severely than older children. They can trigger symptoms including a fever, runny nose, sneezing, cough, rash and muscle aches
Previous outbreaks among children, including panic around Strep A last winter, were blamed on lockdowns weakening immunity against the usually-harmless bugs.
No cases of severe myocarditis have been spotted since March 2023. Cases appear to have peaked in November, however.
Ten cases over the nine-month period have been detected in Wales. This compared to just one in the previous six years.
The WHO, which stuck out the alert last night, labelled the cluster ‘unusual’ and said it may be recommended that childcare facilities and schools are closed if cases surge.
Out of all the affected youngsters, one has died. Eight were treated in intensive care, where they were intubated, put on a ventilator and received circulatory support.
What is the situation?
More than a dozen young children in the UK have developed myocarditis (inflammation of the heart) alongside an enterovirus infection.
How many cases have been detected?
Ten cases have been spotted in South Wales and five have been detected in Southwest England between June 2022 and March 2023.
How many children have been hospitalised?
Eight youngsters were treated in intensive care, where they were intubated, put on a ventilator and received circulatory support.
Details of six cases are unclear, so the number may be higher.
Have any children died?
One child died before being transferred to tertiary care — part of a hospital that delivers highly specialist treatment.
However, a couple in South Wales have shared details of the death of their son Elijah, who died in similar circumstances.
As this death occurred in March 2022, out with the nine-month period defined by Public Health Wales, it is not being probed as part of the official cluster.
What is behind the outbreak?
Experts don’t know.
But health chiefs at Public Health Wales are investigating the reasons for the cluster of cases and to spot any others that may be reported in the coming weeks.
Details on the remaining six cases have not yet been published.
Myocarditis usually occurs following a virus. It is caused by the body’s immune system overreacting to being infected and causing inflammation, which can stay in the heart even after the virus has been cleared.
While some sufferers have no symptoms, it can cause chest pains, palpitations and shortness of breath.
Unwell children also presented with sepsis — which can kill within hours unless it is treated quickly. They were also less interested in eating and drinking.
Five cases were detected in southwest England.
The UKHSA said it was ‘investigating the situation in England’. Officials are looking at potential driving factors behind the increase, too.
PCR testing of nine of the children confirmed they had coxsackie B3 or B4 — types of enterovirus.
Enteroviruses usually cause only mild illness but tends to affect newborns and young children more severely than older kids.
No specific antiviral therapy is available for enteroviruses, so treatment focuses on preventing complications.
The WHO said it was informed of the situation by UK health chiefs on April 5.
Since February, medics in South Wales have been told to look out for cases and test for enteroviruses if it is suspected.
And an incident management team was set up to review evidence across the UK to determine what next steps are needed in its response.
Dr Shamez Ladhani, a consultant paediatrician at the UKHSA, said: ‘Enterovirus is a common infection of childhood, causing a range of symptoms including respiratory disease; hand, foot and mouth, and viral meningitis.
‘In very young babies, enterovirus can, on rare occasions, lead to a severe complication called myocarditis – which causes inflammation of the heart. Most babies and children recover completely from this.
‘Given a higher than average number of cases in Wales in the autumn/winter months in very young babies, UKHSA is investigating the situation in England to see if any similar cases have been observed here and whether there are any factors driving the increase in cases.’
Dr Christopher Williams, consultant epidemiologist for Public Health Wales, said: ‘Enterovirus is a common infection of childhood, causing a range of infections.
‘In very young babies, enterovirus can, in rare cases, also cause a severe illness in the first few weeks of life. Most babies and children recover completely following enterovirus infection.
‘It only affects the heart on very rare occasions. This cluster is unusual due to the number of cases reported in a relatively short time frame.
‘Investigations are now ongoing in collaboration with the paediatric team in the children’s hospital of Wales to understand the reasons why and to investigate any further cases that may be reported in the coming weeks and months.
‘Parents should be reassured that although there has been an increase in cases, this is still an extremely rare occurrence.’
Joann Edwards (pictured with her husband, Christian), from Mountain Ash in South Wales, has told of her child dying after being infected with enterovirus and developing sepsis and heart problems — but his case hasn’t been included in the official tally from Public Health Wales
Mrs Edwards rushed Elijah (pictured) to A&E when he was a week old as he stopped feeding. He was initially diagnosed with sepsis and bronchiolitis — a common chest infection. He was transferred to University Hospital Wales, where medics detected stress on his heart. Elijah was moved to Bristol Children’s Hospital, where he tested positive for enterovirus. Elijah died a few days later at the hospital
The WHO said the risk to public health is ‘low’.
But it noted that enterovirus infection is not among the diseases WHO members have to flag — so a similar pattern may have gone undiagnosed or unreported elsewhere.
It may be recommended to close childcare facilities and schools ‘in certain situations’ to reduce transmission, it said.
But travel restriction to the UK are not recommended, it added.
One mother has told of her child dying after being infected with enterovirus and developing sepsis and heart problems — but the case hasn’t been included in the official tally from Public Health Wales, which was shared with the WHO.
Joann Edwards, from Mountain Ash in South Wales, gave birth to Elijah at Prince Charles Hospital in Merthyr Tydfil on February 25, 2022.
Within a few days of being at home, Elijah became lethargic and was constipated — symptoms which were put down to jaundice.
But Mrs Edwards and her husband Christian rushed him to A&E when he was a week old as he stopped feeding. He was initially diagnosed with sepsis and bronchiolitis — a common chest infection.
He was transferred to University Hospital Wales, where medics detected stress on his heart. Elijah was moved to Bristol Children’s Hospital, where he tested positive for enterovirus.
Elijah died a few days later at the hospital.
Her son’s case isn’t being examined by health officials because it fell outside of the enterovirus season.
However, Cwm Taf Morgannwg Health Board is probing Elijah’s death.
Mrs Edwards said her family has been ignored and was ‘gobsmacked’ after hearing about other cases as they were ‘led to believe that we were a one off’.