New Virus Detected in Blood Transfusion Patients

HHpgV-1 virus found in serum samples from blood transfusion recipients and hemophilia patients.

In a recent study that evaluated changes in the virome composition of blood transfusion recipients pre- and post-transfusion, a new virus was discovered called the human hepegivirus 1 (HHpgV-1). The virus was found in serum samples from blood transfusion patients, indicating its potential for being spread via blood transfusion.

More than 30 million blood components are transfused annually in the United States, so keeping the supply safe for use is of utmost importance to the medical community. In their approach, scientists were able to detect and genetically characterize a novel virus within certain blood supplies that possesses the same qualities as hepatitis C virus (HCV) and human pegivirus (HPgV).

The novel virus, HHpgV-1, was discovered in serum samples from 2 blood transfusion recipients and 2 hemophilia patients who had received plasma-derived clotting factor concentrates. In the blood transfusion patients, the virus was detected only in the post-transfusion samples, indicating blood-borne transmission.

Both hemophiliac patients were viremic over periods of at least 201 and 1981 days. The 5-feet untranslated region (UTR) of HHpgV-1 contained a type IV internal ribosome entry site (IRES) that was structurally similar to that found in HCV and other hepaciviruses.

Phylogenetic analysis of nonstructural genes showed that HHpgV-1 creates a branch within the pegivirus clade that is different from HPgV and homologs infecting other mammals. The HHpgV-1 genome encodes a short, highly basic protein upstream of E1, similar to some pegivirus variants infecting rodents and bats.

This gives the novel virus the potential of possessing a core-like function in packaging RNA during assembly. The results of this study leave researchers in deep consideration over the re-evaluation of the original cirteria by which the genera Hepacivirus and Pegivirus are defined, since the novel virus contains characteristics from both.

As more is discovered about the new virus, scientists will be able to expand the criteria for these genera to include that of the HHpgV-1 virus.