A molecular epidemiological study on hepatotropic virus infections in senior high school freshmen in Hualien area

• Main Authors: Tzu-Ying Ho, 何紫瑩
• Other Authors: Li-Yu Wang
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/u6gdcn

碩士 === 慈濟大學 === 公共衛生研究所 === 93 === Background: Eastern Taiwan is a hyperendemic area of hepatitis virus infection. According to the vital statistics in 2003, the mortality rate of chronic hepatitis and liver cirrhosis were higher in Hualien area as compared with Taiwan area in both sexes. Few studies aimed to evaluate the infections of hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), transfusion-transmitted virus (TTV), and SEN virus (SENV) in adolescents in Taiwan and previous studies were unable to evaluate the influence of TTV or SENV infection alone on liver function. Methods: We conducted a cross-sectional study to assess the prevalence rates of HBsAg and anti-HBs on 2383 senior high school freshmen who participated this study voluntarily, being born after September 1986, having taken a health examination, and having finished a self-help structured-questionnaire. Among these students, 1460 of them who resided in Hualien County were tested for anti-HAV IgM, anti-HAV IgG, anti-HBc IgG, and anti-HCV. A random sample that included 160 students with abnormal liver function (ALT≥25 IU/L) and 498 students with normal liver function (ALT<25 IU/L) was used to investigate the infection rate of TTV and SENV and the relationship between seropositivity of TTV and SENV and liver function. Anti-HAV IgM, anti-HAV IgG, anti-HBc, anti-HBs, HBsAg and anti-HCV were assayed by microparticle enzyme immunoassay. Serum TTV DNA and SENV DNA were detected by semi-nested polymerase chain reaction (semi-nested PCR). Direct sequencing was performed on those with TTV DNA and SENV DNA positivity. Results: The seropositive rate of anti-HAV IgM, anti-HAV IgG, HBsAg, anti-HBs, anti-HBc IgG, anti-HCV, TTV, SENV-D, and SENV-H in senior high school students in Hualien were 0.07%, 6.25%, 1.72%, 46.55%, 5.73%, 0.70%, 18.93 %, 23.36%, and 31.83%, respectively. As compared with those negative for TTV, SENV-D, and SENV-H, means of ALT/AST were both significantly lower in students positive for TTV alone, and both significantly higher in students positive for SENV-H alone. Co-infection of two or more novel hepatotropic viruses was not related to abnormal liver function. Greater than 50% of those with TTV DNA positivity were infected by 1b subtype. Conclusion: The prevalence rates of HAV, HBV, HCV markers were lower than previous studies and the infection of TTV and SENV were frequent in senior high school students in Hualien. No specific factors were significantly associated with TTV and SENV infections in the present study. Our results also indicated that there were synergisms between TTV and HBV infections and between TTV and SENV-H infections. The transmission route of TTV and SENV in eastern Taiwan need further study.