With researchers from the Necker-Enfants Malades Hospital, AP-HP, Inserm at the Imagine Institute, Paris Cité University and the National Veterinary School of Alfort, scientists from the Institut Pasteur have identified a new virus! It is an as yet unknown species of circovirus. Its working name is Human Circovirus 1 (HCirV-1). What are its characteristics ? What are the symptoms ? Is there support?
While the passage of viruses from animals to humans is more and more frequent, it is on the other hand extremely rare to identify new viruses! This is however the case with HCirV-1. It is part of a family of very resistant small DNA viruses. This family of viruses was identified for the first time in animal species in the 1970s. The human circovirus discovered is new, it is distant from the animal circoviruses already known. The Institut Pasteur recently published a press release on the subject.
A 61-year-old patient presented with unexplainable chronic hepatitis. She had been receiving immunosuppressive treatment for 17 years, in connection with her double “heart-lung” transplant. Thanks to very regular monitoring of his double transplant, the researchers were able to obtain numerous samples of pathological tissue over several years and identify, to their great surprise, a new virus. It was this that was responsible for the patient’s hepatitis.
Tissue samples were sequenced using high-throughput sequencing techniques and powerful computer algorithms. The sequences obtained were compared to the sequences of known pathogens. It was indeed a new sequence, corresponding to nothing known!
The effect of infection with this virus
The virus has the ability to multiply in human liver cells. It uses the cellular machinery to replicate itself and then destroys the cell. The deletion of a large number of liver cells causes damage in the functioning of the organ. However, the patient had only very mild symptoms. She was able to benefit from an antiviral treatment and it proved to be effective in fighting the virus and stopping the destruction of liver cells. On the other hand, we do not yet know what is the mode of contamination of this virus (contact, food, etc.).
So that patients infected with this new virus can be treated as quickly as possible, a PCR diagnostic test has been developed. It is a rapid and reliable test which can be used in all cases of hepatitis of unknown origin. A serological test will also be developed soon. This is currently the only known case of human infection with the HCirV-1 virus. But the diagnostic test now available may be able to lift the veil on other cases of hepatitis of unknown origin.
