The (virtual) World Hepatitis Summit (7-10 June) has addressed the World Health Organisation’s (WHO) global response on severe acute hepatitis of unknown etiology that has been seen in children, and said the cases have to be taken seriously.
On 5 April, 2022, the UK highlighted 10 cases of severe acute hepatitis to WHO, and by 15 April, WHO published its first Disease Outbreak News.
In a presentation at the summit, Dr Philippa Easterbrook, technical lead of the incident team at WHO headquarters, confirmed that much of the data are from UK and USA cases, including retrospective cases from October 2021, and that the common viruses causing acute viral hepatitis (hepatitis viruses A, B, C, and E) have not been detected in any of these cases.
“Some cases of hepatitis of unknown etiology are reported every year,” she said, “but in terms of how worried we should be about this outbreak, it’s the first time so many cases of severe acute hepatitis have been seen. A proportion of cases have developed liver failure, required transplantation or resulted in death. It has to be taken seriously. An important step at the moment is to understand its cause.”
The latest data show that 704 cases have been reported from 34 countries, with 112 additional cases pending classification. From this, at least 38 children (5%) required liver transplantation and 10 children (1%) have died. The majority of cases and reporting countries are in the European region; the countries reporting more than five cases are US (246), UK (222), Japan (36), Spain (34), Italy (29), Portugal (15), Belgium (14), the Netherlands (14), Israel (12), Canada (12), Mexico (10), Sweden (9), Ireland (8), Denmark (7).
The WHO confirmed that several avenues of investigation are ongoing into the etiology of these cases. Easterbrook confirmed common bacterial infections have not been detected and there is no clear link to a particular geographic area, or common exposure to specific foods, medications, toxins, animals or to travel. In addition, there is no link to the COVID-19 vaccine, as the majority of cases (85%) were unvaccinated.
One possible cause that is under active investigation is a link to adenovirus, a common viral cause of respiratory or gastrointestinal infections in children, but which does not usually cause serious disease. Another is prior or current COVID infection.
Additional laboratory studies were undertaken by the UK Health Security Agency (UKHSA), and in 179 tested, 116 (68%) confirmed adenovirus detection, and SARS-CoV-2 was detected in 25 of 169 tested (15%). Planned investigations into etiology are ongoing by UKHSA, including more detailed viral sequencing studies to characterise the type of adenovirus, and studies of the immune response of the children. WHO confirmed its key responses will focus on detailed country and case reporting, and to provide more guidance on testing.
The World Hepatitis Summit was organised by the World Hepatitis Alliance and co-sponsored by the WHO. Its mission is to support countries in meeting the targets needed to eliminate viral hepatitis.
Issued by the World Hepatitis Alliance