Modeling long-term persistence after 8 years of hepatitis B booster vaccination in 5- to 15-year-old children.

Vaccination remains the most effective and cost-saving measure to protect against hepatitis B, a global health problem. It is crucial to characterize the persistence of the immune response after booster vaccination. This study aimed to quantify the persistence through mathematical modeling. Booster vaccination against hepatitis B was conducted in children 5-15 years in 2009-10 in Zhejiang Province. There were four dosage formulations of hepatitis B vaccines [Shenzhenkangtai Biotechnology Co. Ltd. Dalianhanxin Biotechnology Co. Ltd. NCPC GeneTech Biotechnology Pharmaceutical Co. Ltd. Sinovac Biotech Co. LTD. China]: 5, 10, and 20 µg hepatitis B vaccines or 5 µg hepatitis A and B (HAB) combination vaccine with a 0-1-6-month schedule. These were randomly administered to children negative for all hepatitis B markers, named as the schedule 2 group. Anti-HBs positive subjects were given one dose of booster, named as the schedule 1 group. Anti-HBs antibody was measured 1, 7, 18, 66, and 102 months after the first booster dose. A linear mixed-effects model was proposed to predict long-term persistence. One hundred two months after the booster dose, the mean anti-HBs levels were 33.8 mIU/mL, with 73.7 mIU/mL for the schedule 1 group and 20.2 mIU/mL for the schedule 2 group. The model predicted that 99.5% of subjects would remain seropositive (≥10mIU/mL) at year 20 post booster vaccination, with 100.0% and 98.8% for the schedule 1 group and the schedule 2 group, respectively, whereas at year 30, the seropositivity rates would decrease to 76.8%, with 99.4% for the schedule 1 group and 62.5% for the schedule 2 group. The immunogenicity of the booster vaccination could persist for at least 8 years. Mathematical modeling may predict even longer, up to 30 years of protection.

Strategies for hepatitis B booster vaccination among children: an 8-year prospective cohort study.

Debate continues regarding the need for a booster vaccination in children who received a universal infant hepatitis B virus (HBV) vaccination. The aim was to explore the need and the strategies for the booster HBV vaccination. 8-year prospective cohort study was conducted among children aged 5-15 years in 2009-2010 in Zhejiang Province. The participants were divided into groups A (<0.1 mIU/mL), B (0.1 to < 1 mIU/mL) and C (1 to <10 mIU/mL) according to the pre-booster anti-HBs antibody levels. 5 µg (group I), 10 µg (group II), 20 µg hepatitis B vaccines (group III) or 5 µg hepatitis A and B (HAB) vaccines (group IV) with 0-1-6-month schedule were randomly administered to children negative for all markers. Blood samples were collected at baseline HBV marker testing, 1 month after the first dose, 1 month, 1 year, 5 years and 8 years after the third dose. Among 4170 children, 2326 (55.8%) were negative for all HBV markers. Group II showed the highest seropositive rates of 92.8%, 99.7%, 97.6%, 90.3% and 83.4% with GMTs of 4194.5 mIU/ml, 4163.9 mIU/ml, 466.9 mIU/ml, 190.6 mIU/ml, 122.6 mIU/ml from 1 month after dose 1 to 8 years after dose 3, respectively (P < .01). Participants in group C showed seropositive rates of 98.9%, 99.9%, 99.5%, 95.5%, 92.8% after the revaccination with GMTs of 6519.6 mIU/ml, 5267.4 mIU/ml, 547.1 mIU/ml, 249.5 mIU/ml, 155.3 mIU/ml, respectively, higher than group A and B (P < .001), except 1 month after the third dose. The 10 µg of HBV vaccine with a 0-1-6-month booster regimen may elicit robust responses and persist for 8 years or longer. Additionally, 1-dose revaccination maybe suitable for children with 1 to < 10 mIU/ml anti-HBs titers.

Safety and immunogenicity of hepatitis E vaccine in elderly people older than 65 years.

BACKGROUND: Hepatitis E virus (HEV) infection is a leading cause of acute hepatitis worldwide, and results in high morbidity and mortality rates among elderly people in China. The hepatitis E vaccine, Hecolin®, has been shown to be safe and highly efficacious among healthy adults aged 16-65 years old. However, there is no data about Hecolin® vaccination in elderly people older than 65 years (y). METHODS: An open-labeled, controlled trial was conducted to evaluate the safety and immunogenicity of Hecolin® among the elderly aged >65 y. A total of 601 eligible participants were enrolled. Among them, 200 elderly people aged >65 y and 201 adults aged 18-65 y were assigned to the Hecolin® groups and vaccinated at day 0, month 1 and month 6. Serum samples were collected for anti-HEV IgG determination at day 0 prior to immunization and at month 7. The remaining 200 elderly people aged >65 y were assigned to the safety control group and received no intervention but were instructed to report any adverse events that occurred during the whole study period in the same way as those in the Hecolin® groups. RESULTS: After receiving 3 doses of Hecolin® with the standard schedule, most (96.7%) of the vaccinated elderly people aged >65 y seroconverted at one month after the final dose (month 7). At month 7, the geometric mean concentrations of anti-HEV IgG were 5.36 (95% CI, 3.88-7.41) and 19.65 (95% CI, 16.81-22.98) among the baseline seronegative and seropositive elderly, respectively. Of the vaccinated elderly, 97.3% (177/182) had anti-HEV IgG levels higher than 1.0 WU/ml at month 7. Hecolin® was very well tolerated in this population. No vaccine-related SAEs were reported. CONCLUSIONS: Hecolin® is immunogenic and well tolerated in elderly people aged greater than 65 years.

A hospital-associated measles outbreak among individuals not targeted for vaccination in eastern China, 2014.

BACKGROUND: An outbreak of measles occurred in early 2014 among individuals not targeted for vaccination-adults, and infants too young to vaccinate, in Xiangshan County, Zhejiang Province, in eastern China. OBJECTIVE: We conducted an investigation to identify risk factors responsible for this outbreak and to provide evidence-based recommendations for measles elimination strategies in China. METHODS: Measles was diagnosed using national standard case definitions. In a case-control study, 20 randomly selected measles patients were matched with controls selected from the same village or community as each case in a 1:2 case-to-control ratio. Controls were matched on age, within 5 years, and gender. We compared exposure histories during the 7-21 days before rash onset of the case and the same time period for the matched controls. We also conducted a measles antibody seroprevalence survey of a convenient sample of residual serum obtained from healthy patients during routine care in a hospital. RESULTS: The outbreak consisted of 45 measles cases, with an attack rate of 8.9/100,000 total population. Among cases, 91.1% (41/45) were adults (ranged 23-51 years) who had unknown vaccination histories; the other cases were infants younger than 8 months of age. The case-control study showed major risk factors to be a visit to Hospital X (OR(MH)=7.3, 95% CI: 1.8-30.7) and treatment in an IV room in Hospital X (OR(MH)=11.0, 95% CI: 1.3-96.1). The seroprevalence survey showed that 88.8% of adults had measles IgG antibodies, and that 100% of children 2-19 years of age were seropositive. CONCLUSIONS: The outbreak was primarily among age groups not targeted for vaccination-primarily adults, but with some children too young to vaccinate. Visiting a hospital was the major risk factor for measles transmission. We conclude that in addition to maintaining high 2-dose coverage with measles vaccine, working with hospital infection control programs to implement evidence-based strategies to prevent or limit hospital transmission is an important action for eliminating measles in eastern China.

Levels, composition profiles and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in sludge from ten textile dyeing plants.

As components of synthetic dyes, polycyclic aromatic hydrocarbons (PAHs) are present as contaminants in textile dyeing sludge due to the recalcitrance in wastewater treatment process, which may pose a threat to environment in the process of sludge disposal. In order to evaluate PAHs in textile dyeing sludge, comprehensive investigation comprising 10 textile dyeing plants was undertaken. Levels, composition profiles and risk assessment of 16 EPA-priority PAHs were analyzed in this study. The total concentrations of 16 PAHs (∑16 PAHs) varied from 1463 ± 177 ng g(-1) to 16,714 ± 1,507 ng g(-1) with a mean value of 6386 ng g(-1). The composition profiles of PAHs were characterized by 3- and 4-ring PAHs, among which phenanthrene, anthracene and fluoranthene were the most dominant components. The mean benzo[a]pyrene equivalent (BaPeq) concentration of ∑16 PAHs in textile dyeing sludge was 423 ng g(-1), which was 2-3 times higher than concentrations reported for urban soil. According to ecological risk assessment, the levels of PAHs in the textile dyeing sludge may cause a significant risk to soil ecosystem after landfill or dumping on soil.

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

OBJECTIVE: To 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. METHODS: Adults 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. RESULTS: A total of 1872 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 (χ(2)=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). CONCLUSIONS: Domestic recombinant hepatitis B vaccines can achieve immunization effects comparable to those of a foreign vaccine.