Hepatitis B virus infection in hemodialysis patients in Japan: Prevalence, incidence and occult hepatitis B virus infection.

Aim: A survey of hepatitis B virus (HBV) infection in hemodialysis (HD) patients was conducted to determine the burden and risk of infection and to suggest preventive measures against HBV infection among HD patients at nine hospitals in Hiroshima, Japan, from 1999 to 2003.

Methods: HBV markers were investigated for 1860 HD patients. The prevalence, incidence of HBV and prevalence of occult HBV were calculated.

Incidence rates of hepatitis B and C virus infections among blood donors in Hiroshima, Japan, during 10 years from 1994 to 2004.

Objective: Although prevalence rates of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections have kept decreasing in blood donors, there is little information on incidence rates of these hepatitis viruses in Japan.

Methods: During 10 years from June 1994 through April 2004, 418,269 inhabitants of Hiroshima, Japan, donated blood (1,409,465 units in total). They were screened for serum markers of HBV and HCV infections, and individuals who developed de novo infections were identified.

Minimum infectious dose of hepatitis B virus in chimpanzees and difference in the dynamics of viremia between genotype A and genotype C.

Background: In planning optimal hepatitis B virus (HBV) blood screening strategies, the minimum infectious dose and early dynamics of HBV need to be determined for defining the window period for HBV DNA as well as for hepatitis B surface antigen (HBsAg).

Study Design And Methods: Pairs of chimpanzees were inoculated with preacute-phase inocula containing HBV of genotype A or genotype C to determine the minimum infectious dose, and two pairs of chimps infected with the lowest infectious dose of genotypes A and C were followed for HBV markers.

Results: The minimum 50 percent chimpanzee infectious dose (CID50) was estimated to be approximately 10 copies for genotype A and for genotype C.

Hepatitis C virus infection in 2,744 hemodialysis patients followed regularly at nine centers in Hiroshima during November 1999 through February 2003.

Patients on maintenance hemodialysis (HD) are at increased risk of infection with hepatitis C virus (HCV). A prospective follow-up study on HCV infection from November 1999 to February 2003 was conducted in nine hemodialysis (HD) units in Hiroshima. A total of 2,744 HD patients were surveyed regularly for HCV RNA in serum.

Early dynamics of hepatitis C virus in the circulation of chimpanzees with experimental infection.

Two chimpanzees were inoculated with hepatitis C virus (HCV) and followed on a daily basis for 12 days. HCV RNA became detectable in their sera on day 5 by polymerase chain reaction with the detection limit of 10(2) copies/ml. Based on an exponential growth observed until 8 or 9 days after inoculation in their sera, the doubling time of HCV in the circulation was estimated at 6.

Titration of hepatitis C virus in chimpanzees for determining the copy number required for transmission.

Objective: To determine the copy number of hepatitis C virus (HCV) RNA, determined by nucleic acid amplification test (NAT) for screening blood units in Japan, that can transmit infection to chimpanzees.

Methods: Fresh-frozen plasma with markers of HCV infection, as well as inocula pedigreed from 1 of them, were evaluated for the infectious activity in chimpanzees.

Results: One unit each (273-282 ml) of fresh-frozen plasma from 2 blood donors or a pool from 13 donors to make a unit, which contained high-titered antibody to HCV but without HCV RNA detectable by NAT, did not infect any of 3 chimpanzees.

Sex- and age-specific carriers of hepatitis B and C viruses in Japan estimated by the prevalence in the 3,485,648 first-time blood donors during 1995-2000.

Objective: Carriers of hepatitis B virus (HBV) and hepatitis C virus (HCV) in Japan were estimated on a national basis.

Methods: Sera from the first-time blood donors aged 16-64 years in eight jurisdictions of the Japanese Red Cross Blood Center during 1995-2000 were tested for hepatitis B surface antigen (HBsAg) and antibody to HCV (anti-HCV). Viremia with HCV was estimated to be present in 70% of donors with anti-HCV.

Lack of epidemiological evidence for a role of resolved hepatitis B virus infection in hepatocarcinogenesis in patients infected with hepatitis C virus in Japan.

Objective: The role of resolved hepatitis B virus (HBV) infection in promoting hepatocellular carcinoma (HCC) in patients infected with hepatitis C virus (HCV) in Japan was evaluated by epidemiological surveys.

Methods: Antibody to hepatitis B core (anti-HBc) was determined in age-matched blood donors, and the frequency was compared with that in patients with HCV-associated HCC in Japan.

Results: Anti-HBc was detected significantly more frequently in the blood donors with than without antibody to HCV (anti-HCV; 76/135 or 56.

Natural histories of hepatitis C virus infection in men and women simulated by the Markov model.

The Markov model was introduced to simulate natural histories of hepatitis C virus (HCV) infection in men and women. The data set was constructed on 942 HCV carriers who were examined at least once a year without receiving antiviral therapies. Based on 2,251 patient-year data, the probabilities of transition between any two of the four clinical states, i.

High incidence of extrahepatic manifestations in an HCV hyperendemic area.

We previously investigated the incidence of extrahepatic manifestations including oral precancerous disease among the inhabitants in a hepatitis C virus (HCV) hyperendemic area in Fukuoka in Japan. The present study design was based on a prospective cohort at the other HCV hyperendemic area. One oral surgeon examined the oral lesions of 59 adult inhabitants (21 men, 38 women; mean age of 70.