Cases of unexplained hepatitis in children reached 650 this past week with the majority developing severe infection and acute liver failure.
On Friday, 27th May, the World Health Organization (WHO) provided an update on the recent cases of unexplained hepatitis in children. As of 26th May, a total of 650 probable cases have come forward from across 33 countries. The WHO defines a probable case as ‘a person presenting with an acute hepatitis (non hep A-E*) with serum transaminase >500 IU/L (AST or ALT), who is 16 years and younger, since 1 October 2021‘. There is currently no definition for a confirmed case as the cause remains unknown.
The aetiology of this severe acute hepatitis remains unknown and under investigation; the cases are more clinically severe and a higher proportion develops acute liver failure compared with previous reports of acute hepatitis of unknown aetiology in children.
World Health Organization
Experts first noticed cases of unexplained hepatitis in April of this year when children in the UK began developing liver inflammation. Doctors could not detect any of the usual viral suspects that commonly cause hepatitis. Moreover, the surge in cases resulted in several hospitalizations and even liver transplants among children aged 10 and younger.
In a recent update, the UK Health Security Agency (UKHSA) announced the confirmation of further 25 cases, bringing the total cases in the UK to 222. The majority of these cases have occurred in children under 5 years of age who initially presented with symptoms of gastroenteritis and then jaundice. Doctors have not reported any deaths from the cases in the UK. However, on a global scale, a total of 9 deaths have occurred as a result of acute liver inflammation. Moreover, at least 38 children have undergone a liver transplant as a result of the infection.
Is it Corona? Is it Adeno?
As per previous reports, a huge proportion of cases tested positive for adenovirus. In the UK, 75% of cases revealed the presence of adenovirus Type 41. Whereas other parts of the world have also found Adenovirus associated virus 2 (AAV-2) in the typed samples. Thus, causing experts to implicate the virus as a probable cause of the unexplained hepatitis cases.
Adenoviruses are commonly linked to causing the common cold in children. The virus spreads via respiratory droplets, close personal contact, and touching contaminated objects. These groups of viruses can infect the eyes, lungs, intestines, urinary tract, and nervous system. Thus, resulting in a wide range of illnesses ranging from mild to severe. These include the common cold, pneumonia, conjunctivitis, and acute gastroenteritis. In some cases, it can also cause a bladder infection or an infection of the brain and spinal cord. Moreover, in immunocompromised individuals, adenoviruses can cause severe illnesses.
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.
Dr. Renu Bindra, Senior Medical Advisor and Incident Director at UKHSA
However, all of the children that tested positive for adenovirus had no history of a medical condition. Nor has adenovirus 41 ever caused hepatitis in healthy children before. Therefore, experts are not convinced about the role of the virus in recent hepatitis cases.
According to WHO’s update, out of the 188 cases that underwent PCR testing, 12% tested positive for SARS-CoV-2. Moreover, many samples have also shown a co-infection of both the novel coronavirus and adenovirus. Therefore, experts are also looking into the role of coronavirus in sudden liver inflammation.
WHO States Global Risk of Hepatitis as Moderate
The WHO has not detected any link between the reported cases. They continue to investigate other possible causes of acute hepatitis such as toxins, co-infections, and environmental exposures. Moreover, it is unclear whether the current surge in cases is higher than what is normally expected over the same period of time.
The source and mode of transmission of the potential aetiologic agent(s) has not yet been determined, and so the likelihood of further spread cannot be fully assessed.
World Health Organization
Approximately 75% of the cases have occurred in children younger than 5 years of age. Since this is too young for a COVID-19 vaccine, experts have ruled hepatitis as a possible side effect of the coronavirus vaccines.
The WHO has assessed the global risk of unusual hepatitis as moderate. Currently, limited data is available on the virus’s histological, epidemiological, and clinical properties. The infection’s actual source and mode of transmission also remain unclear. Therefore, it is not possible to fully assess the infection’s further spread. Although no reports of healthcare-associated infections have occurred so far, experts are not ruling out human-to-human transmission.
Until more is known about the outbreak, experts are urging people to stick to proper hygiene practices and look out for potential signs and symptoms of hepatitis.
