Unconventional transmission mode of the delta virus
The origin of hepatitis D virus (HDV) is currently unknown. HDV is described as an infectious agent that depends on hepatitis B virus (HBV) for envelopment and transmission of its ribonucleoprotein (RNP); yet, as shown in this study, HBV-unrelated viruses, including hepacivirus and flaviviruses, are also able to propagate HDV in vitro and in humanized mice.