@article{oai:ir.kagoshima-u.ac.jp:00005203,
 author = {志方, 俊夫},
 journal = {南方海域調査研究報告=Occasional Papers},
 month = {2016-10-28},
 note = {Viral hepatitis of human being is caused by the various types of hepatitis
viruses, such as hepatitis A virus, B virus, δ virus and unknown non-A, non-B
hepatitis viruses. Although those viruses belong respectivelly different virus
groups, (some one is RNA virus and the other one is DNA virus) the clinical
symptoms and histological features of the liver of each viral hepatitis are quite
similar.
However, there is some difference among liver diseases caused by each virus.
Hepatitis A virus and Indian type non-A, non-B virus only cause acute hepatitis
by transient infection. On the contrary, hepatitis B virus and other non-A, non-B
viruses cause not only acute hepatitis but also various liver diseases, such as
chronic hepatitis, liver cirrhosis and hepatocellular carcinoma due to persistent
infection.
The incidence of type A hapatitis markedly decreased after World War II
in Japan. Whereas, it is still prevalent in South-Asia, Africa and Middle
and South-America. Infection of hepatitis A virus is taken place by fecal-oral
route. However, there is no evidence for proliferation of this virus in the gut.
Hepatitis A virus is only found in the liver, especially in the hepatocytes in
the early stage and in the Kupffer cells in the late stage.
The spectrum of the clinical and pathological features caused by hepatitis B
virus is unusually broad, it also causes chronic hepatitis, liver cirrhosis, healthy
carrier and probably hepatocellular carciuoma due to persistent infection. Recently integration of hepatitis B virus genome into cancer cells of the hepatocellular carcinoma was confirmed by Southern blot hybridization method. Furthermore, several quite similar viruses with hepatitis B virus (hepadna viruses) were disclosed in different animal species, such as woodchuck, Pekin duck, grand squirrel etc. and those virues also cause chronic hepatitis and hepatocellular carcinoma in each animal species., Hepatitis B virus and other hepadna viruses are found mainly in the blood.
Therefore, transmission route of those viruses is quite different from hepatitis A
virus. Transmission is caused by parenteral routes, such as blood transfusion,
intimate contact including sexual intercoures, vertcal transmission at birth. Difference of clinical coures and liver diseases caused by hepatitis B virus mainly depend on the age at which hepatitis B virus infects each persons. Infection in early life, such as newborn or infant usually does not cause acute hepatitis and cause chronic
persistent infection. Some of those hepatitis B virus carriers later develop liver cirrhosis and hepatocellular carcinoma. Whereas, if immunologically competent adults are infected with hepatitis B virus, they develop acute hepatitis and later do not develop chronic hepatitis or liver cirrhosis.
Concerning non-A, non-B hepatitis, causative viruses are not yet disclosed.
Chimpanzee have a susceptibility for those viruses. Hepatocyes of the infected chimpanzees show characteristic ultramicroscopical features. Recently we developed monoclonal antibody specific for non-A, non-B hepatitis by mean of EB virus transformation method of B lymphocytes of convalescent chimpanzee., 志方俊夫（日本大学医学部病理学講座・長崎大学熱帯医学研究所防疫部門）},
 pages = {25--47},
 title = {ウイルス性肝炎の疫学,臨床と病理},
 volume = {6},
 year = {}
}