A further 20 cases of hepatitis have been confirmed in children aged 10 and under, according to the UK Health Security Agency (UKHSA).
It brings the total number of cases across the UK to 222, as of Wednesday May 25.
Of the confirmed cases, 158 are resident in England, 31 are in Scotland, 17 are in Wales and 16 are in Northern Ireland, UKHSA said.
The cases are mainly in children under five, who showed initial symptoms of gastroenteritis illness (diarrhoea and nausea) followed by jaundice.
No children have died.
A small number of children aged over 10 are also being looked into as part of UKHSA’s investigation.
Dr Renu Bindra, senior medical adviser and incident director at UKHSA, said: “Our investigations continue to suggest an association with adenovirus, and we are exploring this link, along with other possible contributing factors including prior infections such as Covid-19.
“We are working with other countries who are also seeing new cases to share information and learn more about these infections.
“The likelihood of children developing hepatitis remains extremely low. Maintaining normal hygiene measures, including making sure children regularly wash their hands properly, helps to reduce the spread of many common infections, including adenovirus.
“We continue to remind everyone to be alert to the signs of hepatitis – particularly jaundice, look for a yellow tinge in the whites of the eyes – and contact your doctor if you are concerned.”
