In recent years, a novel cat hepadnavirus in domestic cats, which is closely related to human hepatitis B virus, has been reported in several foreign countries.However, there have been no reports of cat hepadnavirus identification in Japan, and the infection status in Japan has not been clarified.

　Therefore, this time, this research team collaborated with multiple veterinary hospitals in Japan and attempted to detect the DNA of feline hepadnavirus from 128 cat blood samples in Japan.As a result, 128 out of 1 samples (0.78%) became positive for viral DNA, making it the first identification of cat hepadnavirus in Japan.

　In addition, when the genome sequence of this virus was analyzed and compared with the overseas cat hepadona virus strain, the sequences of the polymerase protein, surface protein and core protein were similar to those of the overseas virus strain, while the X protein. It became clear that there was a large difference from other strains.In other words, it is presumed that the cat hepadnavirus, which was first identified in Japan, is a strain unique to Japan.

　Further analysis of the effects of feline hepadnavirus on cat health is awaited, but the hepatitis marker alanine aminotransferase (ALT) has been elevated for a long time in cats that were positive for the virus this time, and it persists. Hepatitis-like symptoms were observed.It is necessary to continue to study the relationship between the cat hepadnavirus infection status and chronic liver disease, and the significance of the difference in the X protein sequence between overseas and Japanese virus strains.

Paper information:[Journal of Veterinary Medical Science] Identification of domestic cat hepadnavirus from a cat blood sample in Japan