Yongdi Chen

The effects of booster vaccination of hepatitis B Vaccine on anti-HBV surface antigen negative children 11-15 years after primary vaccination

The twin aims of this study were to investigate the changes in anti-HBs IgG levels after booster vaccinations and to compare the effects of different vaccine doses in children aged 11-15 years who were both negative for HBsAg and had an Anti-HBs

Comparison of the effect of two different doses of recombinant hepatitis B vaccine on immunogenicity in healthy adults

The aim of this study was to evaluate the one-month immune response to 2 different doses (10 and 20 μg) of recombinant hepatitis B vaccine in adults aged 20–46 y. Subjects who were negative for hepatitis B surface antigen (HBsAg), hepatitis B antibody (anti-HBs), and hepatitis B core antibody (anti-HBc) were recruited. The participants were divided into 2 groups: group I received 3 doses of 10 μg hepatitis B vaccine at 0, 1 and 3 months, and group II received 3 doses of 20 μg at the same time points. The anti-HBs levels were measured one month after the third vaccination. Among 739 subjects, 62 (9.70%) were positive for HBsAg, and 317 subjects were eligible. The anti-HBs seroprotection rates (anti-HBs ≥10 mIU/mL was considered to indicate seroprotection) after the third vaccination were 88.05% and 94.06% in group I and group II respectively, and the geometric mean titers were 91.69 and 290.23 mIU/mL respectively. The difference in the seroprotection rate was not significant (χ2 = 2.566, P > 0.05), but the GMT after the third dose was significantly lower for group I than for group II (F = 20.587, P < 0.05). Better responses were observed in young adults, especially in group I. In group I, the seroprotection rate and GMT were significantly higher in the 20–35 y group than in the 36–46 y group (P < 0.05); there was no significant difference compared to group II (P > 0.05). The hepatitis B vaccine has good immunological effect; the 20 μg dose can be used in adults aged 20–46 y and the 10 μg dose can be used in subjects aged 20–35 years, and it should be tested on a larger number of subjects before recommending it for adult routine vaccination.

Immunological effects of a 10-μg dose of domestic hepatitis B vaccine in adults

ObjectiveTo evaluate the immunological effects of three types of domestic 10-μg/dose hepatitis B vaccines in adults compared with a foreign vaccine, and to provide scientific evidence in support of adult hepatitis B vaccination.MethodsAdults from five counties (Deqing, Changxing, Nanxun, Wuxing, Anji) in Huzhou City, Shaoxing County and Tongxiang County, Zhejiang Province, China were selected. Blood samples were taken to assess serum HBsAg, anti-HBs, and anti-HBc using a chemiluminescence immunoassay. Adults, aged 16 to 49 years and who were anti-HBs negative at baseline, received hepatitis B immunizations at 0, 1, and 6 months. Anti-HBs levels were assessed one month after the third and final vaccination.ResultsA total of 1 872 adults were immunized and the average positive rate was 89.5%. Four types of hepatitis B vaccine were used, including three from Chinese companies (Shenzhen Kangtai, Dalian High-Tech, and North China Pharmaceutical) and one from a UK company (GlaxoSmithKline). Their seroconversion rates were 81.67%, 95.05%, 89.64%, and 86.81%, respectively. There was a significant difference between the anti-HBs positive conversion rates of the four types (P<0.005) but the seroconversion rates among the different vaccines were not significantly different (χ2=2.123, P=0.145). The average anti-HBs geometric mean titers (GMTs) of non-immune adults immunized with each of the four vaccines were 177.28, 473.23, 246.13, and 332.20 mIU/ml, respectively. There were no statistically significant differences in the GMTs between the three types of domestic vaccine and the foreign vaccine (t=−1.575, P=0.116).ConclusionsDomestic recombinant hepatitis B vaccines can achieve immunization effects comparable to those of a foreign vaccine.

The response of hepatitis B vaccination on seronegative adults with different vaccination schedules

The purpose of this study was to compare the response of hepatitis B vaccination with different vaccination schedules among seronegative adults, and to provide suitable vaccination schedules for floating and fixed population. The study included adults aged 20 to 39 y without prior history of vaccination with hepatitis B vaccine. The serum samples were collected and tested for hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), and hepatitis B core antibody (anti-HBc) levels. Out of all, 686 adults who were negative for anti-HBs, anti-HBc and HBsAg were vaccinated with 10 ug hepatitis B vaccine at 0, 1 and 3, 6 or 12 month schedules, and their antibody titers were monitored. The rates of completion of the vaccination in floating and fixed population were 90.4% and 94.1% respectively (p = 0.061). The anti-HBs positive rates in adults vaccinated at 0, 1 and 3 ,6 or12 month were 83.9%, 88.2% and 94.2% respectively (P = 0.0003). The corresponding geometric mean titers (GMTs) were 61.19 (95%CI:47.10-81.23) mIU/mL, 214.04(95%CI:157.14-291.61) mIU/mL and 345.78(95%CI:251.25-475.77) mIU/mL, respectively ( P < 0.0001). Vaccination of hepatitis B with both 0–1–6 and 0–1–12 month schedules in adults result in better level of immune responses. Also, a longer vaccination schedule (0–1–12 month) may be more suitable for floating population and 0–1–6 month schedule is recommended for the fixed population.

Epidemiologic Features of Enterovirus 71-Associated Hand-Foot-and-Mouth Disease from 2009 to 2013 in Zhejiang, China

Enterovirus 71 (EV71) usually causes hand-foot-and-mouth disease (HFMD) with severe clinical symptoms and even deaths in China. There is no efficient antiviral drug to protect against severe EV71-associated HFMD, making the development of EV71 vaccines therefore a priority. However, the potential target subject population(s) to be immunized with EV71 vaccine are not well understood. In this study, we characterized the epidemiology regarding EV71-associated HFMD on the basis of provincial-level surveillance. We extracted data on EV71-associated HFMD from the National Notifiable Disease Reporting System in Zhejiang Province, China between 1 January 2009 and 31 December 2013 (n = 7650). The higher incidence rate of EV71 cases occurred in those children aged 12–23 months, with boys being predominant. Interestingly, different peaks activities of EV71 infection was observed in different calendar year, with one peak in 2009 and 2013 and two peaks in 2010–2012. However, EV71 infection seemed to predominately occur in warm season and a distinguished cyclic peak that seemed to be of about 12 months. Children aged 12–23 months are thus identified as an important target population for public health intervention, for example, it is recommended that these key subjects immunized with EV71 vaccine. In addition, an enhanced surveillance system for EV71-associated with HFMD needs to focus on generic and phylogenetic analysis.

The one year effects of three doses of hepatitis B vaccine as a booster in anti-HBs-negative children 11–15 years after primary immunization; China, 2009–2011

The aim of this study was to evaluate hepatitis B surface antibody (anti-HBs) levels one year after hepatitis B booster vaccination in anti-HBs-negative (<10 mIU/mL) children 11–15 y after primary vaccination. Anti-HBs titers were examined in 235 children who were negative for hepatitis B surface antigen (HBsAg), anti-HBs, and hepatitis B core antibody (anti-HBc). The children were then divided into 3 groups based on their anti-HBs levels pre-booster: Group I, <0 .1 mIU/mL; Group II, 0.1 to <1 .0 mIU/mL; and Group III, 1.0 to <10 .0 mIU/mL. They were vaccinated with 3 doses of hepatitis B vaccine (0–1–6 month, 20 ug), and anti-HBs levels were measured. One month after the first dose, the anti-HBs positive rates (≥10 mIU/mL) in Groups I–III were 56.14%, 83.61% and 100%. One month after the third dose, the anti-HBs-positive rates in Groups I–III were 96.49%, 98.36% and 100%. One year after the third dose, the anti-HBs-positive rates in Groups I–III were 73.68%, 75.41% and 98.29%, respectively. Protective levels declined more rapidly for those with lower titers. Children with pre-booster anti-HBs titers of 1–9.9 mIU/mL might not need any booster dose, and the children with pre-booster titers of 0.1–0.9 and <0 .1 mIU/mL might need more than one dose booster vaccination.

Effects of hepatitis B vaccine boosters on anti-HBs-negative children after primary immunization.

ABSTRACT This study was aimed at evaluating the changes of hepatitis B surface antibody (anti-HBs) titer after booster vaccinations in 5–15-year-old children with negative antibodies (<10 mIU/mL). 225 subjects (mean age, 9.28 ± 2.95 years) included in the study consisted of 123 males and 102 females, with a complete hepatitis B vaccination during infancy. The participants were divided into 3 groups according to their pre-booster anti-HBs level: Group I, <0.1 mIU/mL; Group II, 0.1 to <1.0 mIU/mL; Group III, 1.0 to <10.0 mIU/mL. All the participants were administered 3 doses of booster hepatitis B vaccination (0-1-6 month, 20 µg), and changes in the levels of antibodies were examined at 4 time-points (one month after the first and the third dose, one year and 5 years after the third dose). The seroprotective rate (defined as anti-HBs ≥10.0 mIU/mL) among 225 subjects at the 4 time-points were 93.8%, 100%, 83.6% and 73.4%, respectively (χ2 = 90.29, p < 0.05). The seroprotective rate (≥10 mIU/mL) and anti-HBs geometric mean titer (GMT) in Group III were always higher than those in the other 2 groups (all p < 0.05). The immune effect of a 3 -dose booster revaccination is good, and the booster-induced immune response was correlated with the pre-booster titer level, and ≥1.0 mIU/mL ensuring a robust positive response, whereas titers below this value may indicate the need for a course of booster vaccination.

Responses to hepatitis B vaccine in isolated anti-HBc positive adults

ABSTRACT Immune responses of isolated anti-HBc subjects are not well characterized in populations in China. This study aimed to evaluate immune responses to hepatitis B vaccination in isolated anti-HBc positive subjects. A cohort of 608 subjects were selected and separated into isolated anti-HBc (negative for HBsAg and anti-HBs, positive for anti-HBc) and control (negative for HBsAg, anti-HBs, and anti-HBc) groups, who were matched by age and sex. All subjects received 3 doses of hepatitis B vaccine (20μg) at months 0, 1, and 3, followed by testing for serological responses 1 month after the third vaccination. The positive seroprotection rate and geometric mean titer (GMT) for hepatitis B surface antibody (anti-HBs) of isolated anti-HBc subjects were significantly lower than those in the control group(86.2% vs.92.1%, P = 0.02; 47.26 vs.97.81 mIU/mL, P < 0.001). When stratified by age, positive seroprotection rate in the isolated anti-HBc group were 92%, 88.5% and 79.4% in the 20–34, 35–49, and 50–60 y old subgroups, respectively (χ2 = 5.919, P = 0.04). Additionally, the GMT level for anti-HBs in the isolated anti-HBc group for different age subgroups were 104.43, 47.87 and 31.79 mIU/mL respectively (χ2 = 19.44, P < 0.001). The GMT level for anti-HBc before vaccination were negatively correlated with GMT for anti-HBs after 3 doses of hepatitis B vaccine (r = −0.165, P < 0.001). In conclusion, isolated anti-HBc positive subjects can achieve good immune responses after hepatitis B vaccination, and the positive seroprotection rate and GMT level for anti-HBs were lower than the control group. Better responses could be observed in young adults, and significant negative correlations were found between GMT of anti-HBc before vaccination and GMT of anti-HBs after vaccination.

Optimal vaccination program for healthy adults in China

There is still no suitable routine hepatitis B immunization strategy for adults in China. To establish an optimal vaccination schedule for healthy adults, we investigated various schedules in healthy adults. In this randomized 5143 healthy adults received 10 μg hepatitis B vaccine at 0, 1 and 3 months(group A), 0, 1 and 6 months(group B), or 0, 1 and 12 months(group C). Blood samples were collected after 1 month and 12 months after the third dose. The geometric mean titer (GMT), seroconversion rate (levels of anti-HBs ≥10 mIU/mL) and high response rate (levels of anti-HBs ≥100 mIU/mL) were assayed. In our study, 2438 healthy adults finished the full vaccination program and follow-up. The seroconversion/sero-protective rate of groups A–C at one and 12 month after administration of the third vaccine dose was 100%, 99.9% and 97.9% verse 64.9%, 75.7% and 79.0%, respectively. GMT for anti-HBs tested in group A to C within 1 or 12 month after the third vaccination was 213.16, 432.58 and 451.47 mIU/ml verse 22.07, 46.70 and 56.18 mIU/ml, respectively. There were significant differences of seroconversion/sero-protective rate and GMT among the 3 groups (p < 0.01). Given the high anti-HBs seroconversion rate and GMT in all 3 groups, a flexible schedule for Hepatitis B vaccine should be recommended to adults, but 0-1-12 schedule is a better choice.

The effects of booster vaccination on combined hepatitis A and hepatitis B vaccine in both anti-HBs and anti-HAV negative children 5–15 y after hepatitis B vaccine primary immunization

In the present study, we investigated the changes in both anti-HAV lgG and anti-HBs lgG levels and compared the antibody seroconversion rates of different doses of combined hepatitis A and hepatitis B vaccine in children. Children who were vaccinated as infants with Hepatitis B vaccine were revaccinated at 5–15 y of age, then the antibody titers were monitored. Among 283 children, this study found that the anti-HAV seroconversion rates (defined as anti-HAV ≥ 1mIU/ml) after the first and the third dose were 79.9% and 100% respectively; these observed differences were statistically significant (P < 0.05); the corresponding geometric mean titers (GMTs) were 4.72 ± 2.63 mIU/ml and 13.46 ± 1.16 mIU/ml respectively. The anti-HBs seroconversion rates (defined as an anti-HBs ≥ 10 mIU/ml) were 82.3% and 99.0% respectively; these observed differences were statistically significant (P < 0.05); and the corresponding titers were 319.95 ± 5.16 mIU/ml and 418.59 ± 3.89 mIU/ml respectively. After the first booster dose, the difference in anti-HAV seroconversion rate was statistically significant in children aged 5–9 y and 10–15 y (P < 0.05), as was the difference of anti-HBs seroconversion, whereas after the third dose the difference was not statistically significant (P > 0.05). This study demonstrated that the immunization effects of booster vaccination with combined hepatitis A and hepatitis B vaccine is successful for children. A single booster dose is adequate for younger children, while three doses are needed for older children.