A Study On The Sero-epidemiology Of Hepatitis B In Children And The Hepatitis B Virus Genotype

ObjectiveThis study aims to explore the epidemiological characteristics and the risk factors of HBV infection among the children aged less than 15 years old,and master the distribution and the clinical implication of distinct hepatitis B virus genotypes in hepatitis B patients. So as to provide pertinent testimony to better control and treatment hepatitis B virus.MethordThe method of multistage systematic sampling was used to selected children aged less than 15 years old ,who was surveyed with questionnaire and detected sero-marker of HBV infection. And 1:2 matched case-control study was used to explore the risk factors of HBV infection in children. Genotypes among patients with hepatitis B virus was detected by PCR-microplate sandwich hybrization-ELISA technique , and multinomal logistic regression was used to analyze the relationship between HBV genotype and its clinical implication .Results(1)The coverage and the timely-birth dose coverage of hepatitis B vaccine were 90.93% and 79.22% respectively in children in Nanping,the positive rate of HBsAg and HBsAb was 3.67%, and 60.95% respectively,the positive rate of HBsAg and HBsAb positive were 1.65% and 67.58% in urbon area,the positive rate of HBsAg and HBsAb were 4.93% and 56.80% in rural area .(2)The result of case-control study on occurrence of HBV infection showed that Intrafamiliar hepatitis B case or HBsAg(+) case and intravenous transfution history were risk factors in the occurrence of hepatitis B infection. Immunization history on hepatitis B vaccine was protective factors in the occurrence of hepatitis B cases.(3) The result of Molecular-epidemiological of hepatitis B virus genotype showed that among 206 HBV infected patients,the proportion of genotype B,C, mixed genotype and D were 50.49 % (104/206) , 38.83 % (80/206) , 6.31 % (13/206) and 4.37% (9/206) respectively.Genotype A,E and F were not found.Mutinomal logistic regression showed that the average age of the patients with genotype B was younger than those with genotype C. The positive rate of hepatitis B e antigen and the serum level of HBVDNA was lower in patients with genotype B than that in those with genotype C . Genotype B appeared significantly more common in patients with asymptomatic carriers(ASC),chronic hepatitis B(CHB )and acute hepatitis(AH).Genotype C was most prevalent in patients with liver cirrhosis(LC) than in those with ASC,AH and CHB.The damage to liver induced by genotype C is severe than that of genotype B.ConclusionResults revealed that although HBsAg positive rate was obviously declined, but the work in inoculation was weaker in rural area than that in urban area. Intrafamiliar hepatitis B case or HBsAg(+) case,intravenous transfution history were the major risk factors in occurrence of hepatitis B infection. The major popular genotypes of HBV were B,C in nanping , genotype C may be association with development of severe liver disease compared with genotype B. Improving the coverage and the tirmely-birth dose coverage of Hepatitis B vaccine, interrupting the transmission of hepatitis B are still the important measures to prevent and contral hepatitis B in nanping.