The effectiveness of 20 μg hepatitis B vaccine used for the prevention of HBV vertical transmission

Abstract To evaluate the efficiency of a 20 μg hepatitis B vaccine(HepB) for disease prevention in two counties in Henan Province, China. A questionnaire was designed to examine the information of hepatitis B surface antigen (HBsAg) positive pregnant women, and their blood samples were collected to test for hepatitis B e antigen (HBeAg), hepatitis B e antibody, and hepatitis B virus (HBV) DNA. Three doses of 20 μg HepB and one dose of hepatitis B immune globulin(HBIG) were administered to newborns. Blood samples were collected from children one month after their complete immunization to test for HBsAg and hepatitis B surface antibody(HBsAb). A total of 419 HBsAg positive-pregnant women and 430 newborns were investigated. The average age of pregnant women was 29.6 ± 4.3 years, with an HBeAg positive rate of 29.1% (122/419). All newborns received their first dose of 20 μg hepatitis B vaccine and 100 IU HBIG within 12 h after birth. Six infants (1.9%, 6/319) tested positive for HBsAg and negative for HBsAb after one month of receiving the three basic doses of HepB. The geometric mean concentration(GMC) of HBsAb-positive infants was 861.6 mIU/mL, and their HBsAb antibody titers decreased with age. Immunization of children born to HBsAg-positive mothers with 20 μg HepB got the satisfactory effect on preventing mother-to-child transmission

An epidemiological serosurvey of hepatitis B virus shows evidence of declining prevalence due to hepatitis B vaccination in central China

Objective: The hepatitis B vaccine was first introduced into the routine immunization program in Henan Province, China in 1992. In 2012, a survey was conducted to evaluate the protective effects of hepatitis B vaccination for the populations born during the preceding 15 years. Methods: A multistage stratified random cluster sampling method was used to collect samples. The participants were interviewed and relevant information was obtained for the population aged 1 to 14 years using a standardized questionnaire; a 2- or 3-ml serum sample was taken from each participant to measure hepatitis B surface antigen (HBsAg) and hepatitis B core antibody (anti-HBc). Association and logistic regression analyses were conducted to determine relationships between these parameters. Results: A total of 13 207 residents aged 1 to 14 years residing in 60 villages or communities in Henan, China were surveyed and had their blood collected. Serological analysis revealed that the HBsAg and anti-HBc prevalences were 0.8% and 2.6%, respectively. The HBsAg prevalence among children under 5 years of age was 0.5%, showing a decline of 96% compared to the average national HBsAg prevalence in 1992. Children had a higher likelihood of HBsAg positivity if they had an HBsAg-positive family member (odds ratio (OR) 4.26), no history of vaccination (OR 2.06), were born in a smaller township hospital or at home (OR 1.61), were aged 10–14 years (OR 2.07), or were living in a rural area (OR 2.01). Conclusions: The HBsAg prevalence rate in persons under 15 years of age has dropped significantly in Henan Province after two decades of vaccination. Thus millions of chronic HBV infections have been prevented

Emergence and transmission pathways of rapidly evolving evolutionary branch C4a strains of human enterovirus 71 in the Central Plain of China.

BACKGROUND: Large-scale outbreaks of hand, foot, and mouth disease (HFMD) occurred repeatedly in the Central Plain of China (Shandong, Anhui, and Henan provinces) from 2007 until now. These epidemics have increased in size and severity each year and are a major public health concern in mainland China. PRINCIPAL FINDINGS: Phylogenetic analysis was performed and a Bayesian Markov chain Monte Carlo tree was constructed based on the complete VP1 sequences of HEV71 isolates. These analyses showed that the HFMD epidemic in the Central Plain of China was caused by at least 5 chains of HEV71 transmission and that the virus continued to circulate and evolve over the winter seasons between outbreaks. Between 1998 and 2010, there were 2 stages of HEV71 circulation in mainland China, with a shift from evolutionary branch C4b to C4a in 2003-2004. The evolution rate of C4a HEV71 was 4.99×10(-3) substitutions per site per year, faster than the mean of all HEV71 genotypes. The most recent common ancestor estimates for the Chinese clusters dated to October 1994 and November 1993 for the C4a and C4b evolutionary branches, respectively. Compared with all C4a HEV71 strains, a nucleotide substitution in all C4b HEV71 genome (A to C reversion at nt2503 in the VP1 coding region, which caused amino acid substitution of VP1-10: Gln to His) had reverted. CONCLUSIONS: The data suggest that C4a HEV71 strains introduced into the Central Plain of China are responsible for the recent outbreaks. The relationships among HEV71 isolates determined from the combined sequence and epidemiological data reveal the underlying seasonal dynamics of HEV71 circulation. At least 5 HEV71 lineages circulated in the Central Plain of China from 2007 to 2009, and the Shandong and Anhui lineages were found to have passed through a genetic bottleneck during the low-transmission winter season