Hepatitis B vaccination among 1997-2011 birth cohorts in rural China: the potential for further catch-up vaccination and factors associated with infant coverage rates

Determinants of incomplete childhood hepatitis B vaccination in Sierra Leone, Liberia, and Guinea: Analysis of national surveys (2018-2020)

Vaccination against hepatitis B virus (HBV) is effective at preventing vertical transmission. Sierra Leone, Liberia, and Guinea are hyperendemic West African countries; yet, childhood vaccination coverage is suboptimal, and the determinants of incomplete vaccination are poorly understood. We analyzed national survey data (2018-2020) of children aged 4-35 months to assess complete HBV vaccination (receiving 3 doses of the pentavalent vaccine) and incomplete vaccination (receiving <3 doses). Statistical analysis was conducted using the complex sample command in SPSS (version 28). Multivariate logistic regression was used to identify determinants of incomplete immunization. Overall, 11,181 mothers were analyzed (4,846 from Sierra Leone, 2,788 from Liberia, and 3,547 from Guinea). Sierra Leone had the highest HBV childhood vaccination coverage (70.3%), followed by Liberia (64.6%) and Guinea (39.3%). Within countries, HBV vaccination coverage varied by socioeconomic characteristics and healthcare access. In multivariate regression analysis, factors that were significantly associated with incomplete vaccination in at least one country included sex of the child, Muslim mothers, lower household wealth index, <4 antenatal visits, home delivery, and distance to health facility vaccination (all p < 0.05). Understanding and addressing modifiable determinants of incomplete vaccination will be essential to help achieve the 2030 viral hepatitis elimination goals.

Effect of a Community-Based Hepatitis B Virus Infection Detection Combined with Vaccination Program in China

Evidence on the effectiveness of hepatitis B virus (HBV) infection screening and vaccination programs remains rare in China. We used a quasi-experimental method, propensity score matching, to evaluate the effects of a community-based HBV infection detection combined with vaccination (HBVIDV) program in a pilot. Data were retrieved from the HBVIDV program implemented between July 2019 and June 2020. Outcomes were the difference between the treatment and control groups in hepatitis B vaccination (≥1 dose), hepatitis B vaccine series completion (≥3 doses), and serologic evidence of vaccine-mediated immunity. Altogether, 26,180 individuals were included, where 6160 (23.5%) individuals were assigned to the treatment group, and 20,020 (76.5%) individuals were assigned to the control group. After propensity score matching, 5793 individuals were matched. The rates of hepatitis B vaccination, hepatitis B vaccine series completion, and prevalence of vaccine-mediated immunity in the treatment and control groups were 29.0% vs. 17.8%, 22.1% vs. 13.1%, and 38.2% vs. 27.6%, respectively. The HBVIDV program was significantly associated with increased hepatitis B vaccination rate (OR, 1.884, 95% CI 1.725-2.057), hepatitis B vaccine series completion rate (OR, 1.872, 95% CI 1.696-2.065), and prevalence of vaccine-mediated immunity (OR, 1.623, 95% CI 1.501-1.755). The greater magnitude of association between HBVIDV program and outcomes was observed among adults aged 35-54 years and adults who live in rural areas. The HBVIDV program was effective in increasing the hepatitis B vaccination rate, hepatitis B vaccine series completion rate, and prevalence of vaccine-mediated immunity among adults in the pilot. Further focusing the program on special populations and regions may produce more effective results.

Rotavirus Infection and Vaccination: Knowledge, Beliefs, and Behaviors among Parents in Italy

This study was designed to investigate the knowledge, beliefs, and behaviors about rotavirus infection and its vaccination in a sample of parents in Naples, Italy. The survey was conducted between June and December 2018 among parents of children aged 3 months to 3 years. A total of 40.7% of the study subjects declared that they had heard about rotavirus infection and 60.8% and 59.2% were aware about the vaccination and of its availability in Italy. Parents with a child aged <1 year and those who reported the physicians as source of information were more likely to have heard about rotavirus infection and to know that the vaccination is available in Italy. More than half (56.4%) were worried that their children could have a rotavirus gastroenteritis and this was most likely to occur in those who have heard about rotavirus infection. Only 15.3% declared that they had immunized their children against rotavirus infection. Parents who considered it dangerous for their children to contract the rotavirus gastroenteritis, those who considered the rotavirus vaccine useful, and those who had received information by physicians were more likely to have vaccinated their children against the infection. More than half of the parents who did not immunize their children expressed their willingness to vaccinate them. Developing and implementing additional public education programs are needed for better knowledge toward rotavirus infection and vaccination and a high coverage among parents.

Hepatitis B Vaccination among 1999⁻2017 Birth Cohorts in Zhejiang Province: The Determinants Associated with Infant Coverage

This study aimed to investigate the coverage of hepatitis B vaccine (Hep B) and its completeness and timeliness for birth cohorts from 1999 to 2017 in Zhejiang province, East China. Demographic characteristics and vaccination records of Hep B of children born from 1 January 1999 to 31 June 2017 were extracted from the Zhejiang provincial immunization information system. The timeliness of the first dose of Hep B (Hep B1) was defined as the proportion of children who received the Hep B1 within 24 h after birth among the target population. The completeness of Hep B was defined as the proportion of children who completed the three-dose series of Hep B before 7 years of age. The demographic characteristics of the target population were described. The coverage of each dose of Hep B, the timeliness of Hep B1, and the completeness of Hep B for each birth cohort were described. A logistic regression model was applied to detect the determinants of the timeliness of Hep B1 and the completeness of Hep B vaccination. The coverage of Hep B1 increased from 90.3% to 98.3%, the coverage of Hep B2 increased from 88.8% to 96.1%, and the coverage of Hep B3 increased from 86.4% to 94.2%. The timeliness of Hep B1 increased from 80.3% to 91.3%. The completeness of Hep B increased from 81.3% to 91.5%. The determinants of timeliness of Hep B1 included children’s delivery place, immigration status, maternal education level, and economic development level of resident area. The determinants of completeness of Hep B included children’s delivery place, immigration status, maternal education level, economic development level of resident area, maternal occupation, and frequency of vaccination service. Zhejiang province had achieved significant improvements in the timely administration of Hep B1 and the completeness of Hep B. To accelerate progress toward additional reductions in the transmission of hepatitis B virus, further efforts need to be focused on improving the timeliness of Hep B1 vaccination and reducing the drop-outs among disadvantaged children with the risk factors identified in this study.