15 babies - 10 in Wales and five in England - were found with myocarditis.
One baby died and seven others were admitted to hospital after an "unusual" cluster of heart infections was detected in south Wales and southwest England, according to a report in Independent. The virus is "unusually mild" but triggered a serious heart condition, the outlet further said. The World Health Organisation (WHO) said on Tuesday that it was made aware of an increase in myocarditis - also known as inflammation of the heart - among the newborns in the region over the past year.
The Telegraph said that 15 babies - 10 in Wales and five in England - were found with myocarditis. Nine of them tested positive for enterovirus, which causes respiratory illness, hand, foot and mouth disease, and viral meningitis.
It is very rare for young babies to develop myocarditis, according to WHO. The health body also said that despite these cases, the risk to public health remains low.
"The reported incident represents an increase in both the number and severity of enterovirus infections in infants under the age of one month," the health body said in Tuesday's announcement.
The Telegraph quoted UK Health Security Agency (UKHSA) as saying that a "higher than average number of cases" of enterovirus had been observed in "very young babies" in Wales over the autumn and winter months.
"We are 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," said Dr Shamez Ladhani, a consultant pediatrician at UKHSA.
Pediatricians in south Wales region were alerted about the recent cases in February, and were told to be aware of myocarditis as a potential cause of infants and newborns presenting in shock.