Geographic and ethnic variations of long-term efficacy and immunogenicity of hepatitis B vaccination in Hualien, a HBV hyperendemic area

HBV infection in indigenous children, 20 years after immunization in Taiwan: A community-based study

“…Indigenous ethnicities were reported to be more hyporesponsive to hepatitis B vaccine than were Han Chinese populations (Hsu et al, 1996), which might lead to vaccine failure; a genetic basis for immune hyporesponsiveness to hepatitis B vaccine in the Bunun ethnicity, one of the largest tribes in Taiwan, has also been mentioned (Huang et al, 2001). However, the difference in efficacy of hepatitis B vaccination among indigenous ethnicities is a controversial issue (Wang et al, 2006). The seroprevalence of positive-anti-HBs in indigenous children did not differ from that of metropolitan Han Chinese children in the current study.…”

Ethnicity, substance use, and response to booster hepatitis B vaccination in anti-HBs-seronegative adolescents who had received primary infantile vaccination

“…Moreover, our seroepidemiological study showed that the anti-HBs seropositive rates for indigenous and Chinese senior high school freshers who were born after July 1987 were 39.6% and 45.0%, respectively [13]. The overall anti-HBs seropositive rate after a booster dose of HB vaccination in adolescents who had received primary HB vaccination 15 years before could be approximated by (p 1 + (1 À p 1 ) * p 2 ), where p 1 is the anti-HBs seropositive rate before booster and p 2 is the response rate in booster recipients.…”

“…It was estimated that the duration of protection was at least 15 years in those who had received complete series of primary HB vaccination [11]. However, several recent studies showed that less than a half of adolescents who had received primary HB vaccination 10-15 years before had residual antibody against hepatitis B surface antigen (anti-HBs) titers of 10 mIU/mL or more [12,13]. Moreover, chronic HBV infection in vaccinated children had been reported by several recent researches [14][15][16][17][18][19][20][21].…”

Assessment of Immunization to Hepatitis B Vaccine among Children under Five Years in Rural Areas of Taiz, Yemen

“…Lower levels of anti-HBs antibodies could also be related to existing problems with the cold chain of vaccines in rural areas that lead to decreased efficacy of the pentavalent vaccine. Lower responses to HBV vaccine in low socioeconomic areas have been reported in Taiwan [27] and significant correlation between nutritional status and the response to HBV vaccination has been reported in Senegal and Cameron [28]. In addition, Losonsky and coworkers reported association between low weight and poor weight gain in the first 6 months of life with decreased immunogenicity after three doses of HBV vaccine in the United States [29].…”