A research team discovers a previously unknown virus while investigating the cause of a patient's hepatitis.
Many questions are still open.
Paris – A research group at the French Institut Pasteur has discovered a new virus that can apparently make people sick.
The previously unknown circovirus, which has been given the provisional name "human cicovirus 1" (HCirV-1), was found in a patient who was struggling with liver disease.
"The patient had unexplained chronic hepatitis with some symptoms," said Marc Eloit, a co-author of the study, which was published in the journal
Emerging Infectious Diseases
The 61-year-old patient had had a heart and lung transplant 17 years previously and has been observed regularly ever since.
"We had access to a large number of samples from different years and were therefore able to identify this new virus," Eloit said in a statement.
"That was completely unexpected."
Research team finds previously unknown virus - it infects liver cells
The research team analyzed tissue samples from the 61-year-old to look for microbial sequences and compare them to the sequences of known microbes. explains Eloit.
Thousands of RNA sequences were analyzed in parallel using algorithms until the research team identified a previously unknown circovirus species.
No other viral or bacterial sequences were found.
The research team found that the newly discovered virus infects human liver cells, multiplies inside them and thereby damages them – which is why the patient had hepatitis symptoms.
Finding hepatitis triggers is not always easy
Finding the cause of hepatitis of unknown origin is still a challenge today, as illustrated by cases of hepatitis in children in the UK and other countries around the world over the past year.
"We need to know the cause of the hepatitis and, more importantly, whether it is viral or not in order to offer appropriate treatment," explains Anne Jamet, a co-author of the study.
Possible symptoms of hepatitis:
yellowing of the skin/eyes (jaundice)
loss of appetite
Circoviruses are no strangers - they were first detected in various animal species in 1974.
In animals, the highly resilient DNA viruses can cause respiratory, kidney, skin and reproductive problems.
According to the research group, the patient's symptoms remained mild, and the virus could only be identified because she was closely monitored after her double organ transplant.
It is still unclear whether the newly discovered virus is circulating in humans or comes from animals, and the source of the infection is also unknown.
The research group has developed a PCR test that can be used to check for cases of hepatitis with an unknown trigger.