Acute hepatitis of unknown cause in children


As of 18 May, 43 probable cases of children with hepatitis of unknown cause have been identified in Ireland since 1st October 2021 and a small number of children are under investigation. This is more than would usually be expected over this period of time. To date no single virus has been identified in all cases. Investigations are currently ongoing to identify the cause of these illnesses. Data are provisional and based on information available at the time of reporting and are subject to change [Acute hepatitis of unknown aetiology report]

All probable cases are in children between the ages of 0 and 16 years of age, 42 of the 43 cases were hospitalised. Two children have received a liver transplant and there has been one death associated with this disease.

In the UK, health authorities have also reported an increase in hepatitis of unknown cause in children. Investigations are underway in the UK to determine the cause of the illness. Information gathered thus far from the UK investigations suggest that the recent cases of hepatitis may be linked to adenovirus infection, however this theory is still under investigation. The Irish cases have no links to the UK cases.

The common viruses that cause hepatitis (hepatitis viruses A, B, C, and E) have not been detected in any of the cases. One area being explored is whether the hepatitis cases are linked to an increase in infections caused by adenovirus, a common cause of childhood and adult illnesses typically causing mild cold- or flu-like illness, or diarrhoea. Adenovirus infections rarely cause hepatitis. Other possible causes such as another infection (including COVID-19) or something in the environment are also being investigated. In Ireland, as in other countries, investigations are underway to determine if current or prior COVID-19 infection may increase the risk of this disease in some children. None of the Irish cases who were tested on admission to hospital had evidence of COVID-19 infection at that time. The majority of the cases had not received COVID-19 vaccination. Ireland is liaising closely with ECDC, UK and WHO colleagues in efforts to identify the cause of this illness.

GPs and paediatric consultants are aware of the recent increase in cases of hepatitis amongst children and will be alert to identify any further cases that may develop.

Advice for parents on symptoms of hepatitis
Parents are advised to go to their GP if their child develops symptoms of hepatitis. Symptoms of hepatitis can include:

  • pale, grey-coloured poo (stools)
  • dark urine
  • yellowing of the eyes and skin (jaundice)

If their child has any of these 3 symptoms, they should contact their GP without delay. The GP will assess the child and refer on for further assessment as indicated.

Other symptoms include:

  • muscle and joint pain
  • a high temperature
  • feeling and being sick
  • feeling unusually tired all the time
  • a general sense of feeling unwell
  • loss of appetite
  • tummy pain
  • itchy skin

Parents are advised to go to their GP if their child develops symptoms of hepatitis. The GP will assess the child and refer on for further assessment as indicated.

If your child is unwell with respiratory or diarrheal or hepatitis symptoms keep your child at home and do not send to crèche/preschool/school until they are better.

Good respiratory and hand hygiene, including supervising hand washing in young children, can help to prevent adenovirus and other infections that can cause hepatitis.

Further information
Increase in hepatitis cases - information leaflet for parents

UK Health Security Agency - Increase in hepatitis cases (liver inflammation) in children under investigation 28/07/2022

WHO - Acute hepatitis of unknown aetiology in children - Multi-country (12/07/2022)

Joint ECDC/WHO Regional Office for Europe Hepatitis of Unknown Origin in Children Surveillance Bulletin – (26/08/2022)’