Abstract
BackgroundHepatitis B virus (HBV) infection remains a severe public health problem. Investigating its prevalence and trends is essential to prevention.MethodsTo evaluate the effectiveness of HBV vaccination under the 1992 Intervention Program for infants and predicted HBV prevalence trends under the 2011 Program for all ages. We conducted a community-based investigation of 761,544 residents of 12 counties in Zhejiang Province selected according to their location, population density, and economic development. The HBV prevalence trends were predicted by a time-shifting approach. HBV surface antigen (HBsAg) and alanine amino transferase (ALT) were determined.ResultsOf the 761,544 persons screened for HBsAg, 54,132 were positive (adjusted carrier rate 6.13%); 9,455 had both elevated ALT and a positive HBsAg test (standardized rate 1.18%). The standardized HBsAg carrier rate for persons aged ≤20 years was 1.51%. Key factors influencing HBV infection were sex, age, family history, drinking, smoking, employment as a migrant worker, and occupation. With the vaccination program implemented in 2011, we predict that by 2020, the HBsAg carrier rate will be 5.27% and that for individuals aged ≤34 years will reach the 2% upper limit of low prevalence according to the WHO criteria, with a standardized rate of 1.86%.ConclusionsThe national HBV vaccination program for infants implemented in 1992 has greatly reduced the prevalence of HBV infection. The 2011 program is likely to reduce HBV infection in Zhejiang Province to a low moderate prevalence, and perinatal transmission is expected to be controlled by 2020.
Highlights
Hepatitis B virus (HBV) infection is a serious problem worldwide[1,2]
Of the 761,544 persons screened for HBV surface antigen (HBsAg), 54,132 (7.11%) were positive, with a standardized HBsAg carrier rate of 6.13% (95% confidence interval [CI] 6.08, 6.19)
Of the 727,746 subjects screened for both HBsAg and ALT, 9,455 (1.3%) had both indicators of hepatitis, with a standardized rate of 1.18%
Summary
2 billion infected people are alive, of whom 350 million have chronic infection, 75% reside in the Asia Pacific region, and about 1 million per year die[3,4,5,6].In China, the HBV surface antigen (HBsAg) carrier rate was 8.75% in 1979[7], 9.75% in 1992[8], and 7.18% in 2006[9]. Because it is the most effective prevention strategy[10,11], an HBV vaccination program for infants was implemented in China in1992 (1992 Program) and caused a significant decline in HBV prevalence[9].
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have