A new hepatitis alert was issued by the Centers for Disease Control and Prevention (CDC) Wednesday telling doctors to take liver samples from the sickest patients — after five children died from the disease in the U.S. and 15 needed a liver transplant.
It comes as scientists remain stumped as to the cause behind the mystery illness, with adenovirus — which can cause the common cold — currently the chief suspect.
In its second alert in three weeks the CDC recommended clinicians widen their search for an adenovirus infection by taking samples from the organ ‘if available’, as well as collecting stool, throat and blood specimens to be tested for adenovirus.
Previously, the agency had only suggested taking samples from one of these — excluding the liver — to scan for the little-known virus.
Earlier this week Hawaii and Massachusetts became the 25th and 26th states to declare suspected mysterious hepatitis cases in children.
The U.S. currently has more than 100 cases suspected or confirmed and the highest death toll in the world, behind Indonesia which has reported three deaths.
Nearly 300 mysterious hepatitis cases have been spotted in children worldwide to date, with most in the UK (160) and U.S. — although this may be because the countries have better surveillance systems.
Scientists are puzzled as to what is causing the outbreak, but the leading theory is that it is triggered by adenovirus which most — but not all — patients have tested positive for.
Other hypotheses being investigated include that lockdowns have weakened children’s immunity, or that a previous Covid infection or even exposure to a pet dog could be to blame.
The above map shows the 26 states that have confirmed or suspected hepatitis cases according to the CDC. Massachusetts and Hawaii became the 25th and 26th states to reveal they are probing suspected cases of the illness (yellow), with Puerto Rico also having reported at least one case
The CDC said in the update — aimed at clinicians — that it was searching for ‘any relationship’ between adenovirus infections and hepatitis.
But it added that other causes of the disease also had not been ruled out.
Cases being investigated include historical ones dating back to October 2021, alongside those that are newly identified.
Q&A: What is the mysterious global hepatitis outbreak and what is behind it?
What is hepatitis?
Hepatitis is inflammation of the liver that is usually caused by a viral infection or liver damage from drinking alcohol.
Some cases resolve themselves, with no ongoing issues, but a fraction can be deadly, forcing patients to need liver transplants to survive.
What are the symptoms?
People who have hepatitis generally have fatigue, loss of appetite, nausea, vomiting, abdominal pain, dark urine, light-colored stools and joint pain.
They may also suffer from jaundice — when the skin and whites of the eyes turn yellow.
Why are experts concerned?
Hepatitis is usually rare in children, but experts have already spotted more cases in the current outbreak than they would normally expect in a year.
Cases are of an ‘unknown origin’ and are also severe, according to the World Health Organization. It has caused up to two deaths and 18 liver transplants.
What are the top theories?
Experts say the cases may be linked to adenovirus, commonly associated with colds, but further research is ongoing.
This, in combination with Covid infections, could be causing the spike in cases.
The WHO reported adenovirus has been detected in at least 74 of the cases. At least 20 of the children tested positive for the coronavirus.
British experts tasked with investigating the spate of illnesses believe the endless cycle of lockdowns may have played a contributing role.
Restrictions may have weakened children’s immunity because of reduced social mixing, leaving them at heightened risk of adenovirus.
This means even ‘normal’ adenovirus could be causing the severe outcomes, because children are not responding to it how they did in the past.
Other scientists said it may have been the adenovirus that has acquired ‘unusual mutations’.
This would mean it could be more transmissible or better able to get around children’s natural immunity.
New Covid variant
UKHSA officials included ‘a new variant of SARS-CoV-2’ in their working hypotheses.
Covid has caused liver inflammation in very rare cases during the pandemic, although these have been across all ages rather than isolated in children.
The CDC has noted environmental triggers are still being probed as possible causes of the illnesses.
These could include pollution or exposure to particular drugs or toxins.
Massachusetts yesterday said it was probing two hepatitis cases in children — who have not been named — which both tested negative for adenovirus.
They did not reveal the condition of the children, or when the suspected infections occurred.
Hawaii also reported its first case of the inflammatory liver disease yesterday, saying the child was under 10 years old and hospitalized for several days at the end of April with abdominal pain and a fever.
Revealing the case late Monday, Hawaii’s Department of Health said: ‘An extensive medical investigation was performed and there are a number of laboratory test results outstanding.
‘At this time, no cause has been determined. DOH is collaborating with the CDC to identify the cause of the hepatitis case.’
Cases of the mysterious hepatitis have now been detected in 26 states, including: Alabama, Arizona, California, Colorado, Delaware, Florida, Georgia, Hawaii, Idaho, Illinois, Indiana, Louisiana, Massachusetts, Michigan, Minnesota, Missouri, North Carolina, North Dakota, Nebraska, New York, Ohio, Pennsylvania, Tennessee, Texas, Washington and Wisconsin.
At least one case has also been reported in the territory of Puerto Rico.
The CDC has refused to reveal where the five U.S. deaths occurred, citing ‘confidentiality issues’.
But at least one was in Wisconsin, where the Department of Health confirmed last month it was probing a fatality linked to the illness.
In a press conference last week, the CDC’s deputy director for infectious diseases, Dr Jay Butler said most of the youngsters had ‘fully recovered’ following the illness.
He said scientists were still probing cases to establish a cause but that adenoviruses were ‘top of the list’.
However, Butler added it was unclear whether an adenovirus infection alone was causing the illness or if it was linked to an immune reaction to a particular strain or something the children had been exposed to.
He stressed, however, that the CDC was not recording a significantly higher number of hepatitis cases in children than it expected for this time of year.
‘I think we are seriously considering whether or not this may be something that has happened ata low level for a number of years, and we just haven’t documented it,’ he said.
Last week the World Health Organization said it was investigating 50 possible causes of the illness.
Hepatitis is normally rare in children, but earlier this year the UK raised the alarm over a mysterious outbreak in children after spotting more cases in January than it would normally expect.
Other countries quickly followed, with the U.S. reporting its first nine cases in Alabama last month. Each of those children required hospital care.
CDC chiefs admitted they had been aware of the cases but did not raise an alert initially because it appeared to be an isolated incident.
They have since issued a health notice asking any states with mysterious hepatitis cases to report them.
Top experts fear health officials will not get to the bottom of what is behind the outbreak for at least another two months, however.
Parents are being told that despite the spate of cases there is an ‘extremely low’ risk of their child coming down with hepatitis.
They are being advised to keep an eye out for the key warning signs, however, been told that their children face a very low risk of coming down with hepatitis.
Jaundice — the yellowing of the skin and whites of eyes — is the most common sign, followed by vomiting and pale stools.
Dr Meera Chand, the director of emerging infections at the UK Health Security Agency, said: ‘It’s important parents know the likelihood of their child developing hepatitis is extremely low.
‘However, 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.
‘Our investigations continue to suggest that there is an association with adenovirus and our studies are now testing this association rigorously.
‘We are also investigating other contributors, including prior SARS-COV-2, and are working closely with the NHS and academic partners to understand the mechanism of liver injury in affected children.’
Most of the cases have been detected in the UK (163) and U.S. (109), which have some of the strongest surveillance systems.
The liver inflammation condition has also been spotted in Spain (22), Israel (12), Italy (9) and Denmark (6), among other countries.