Seroprotection after hepatitis B vaccination amongst infants aged between 12 and 24 months in Ho Chi Minh City, Vietnam

Objective:To assess levels of HBs Ab amongst infants who received hepatitis B vaccine in the Expanded Program on Immunization in Vietnam.Methods:A cross-sectional study was carried out at 16 community health centers from February 2016 to July 2017.Eligible infants were tested for HBs Ab and HBs Ag.Structured questionnaires were used to collect relevant information about the demographics of the parents/caregivers and their infants after physical examination.Results:A total of 199 eligible infants were selected with a mean age of(17.3±4.5)months.Protective antibody levels with HBs Ab≥10 m IU/m L were detected in 68.3%of infants.Of these,antibody levels from 10 to 99 m IU/m L were 48.5%of those tested and antibody levels≥100 ml U/m L were recorded as 51.5%.No cases were recorded of being infected with hepatitis B virus.The rate of positive HBs Ab level in those who were not wasting and≥18 months old was less than that among those who were<18 months old(OR 0.49,95%CI:0.26-0.92,P<0.05)while the infants with wasting and<18 months were less likely to be positive HBs Ab than those who were not wasting and of the same age group(OR 0.15,95%CI:0.04-0.55,P<0.05).Conclusions:Seroprotection against hepatitis B virus was low in the infants tested(at 68.3%),which suggests that the hepatitis B vaccine should be administered with one additional dose for infants between 12 and 24 months of age,particularly those with wasting.

The coverage and challenges of increasing uptake of non-National Immunization Program vaccines in China:a scoping review

Background Non-National Immunization Program (NIP) vaccines have played an important role in controlling vaccine-preventable diseases (VPDs) in China. However, these vaccines are paid out of pocket and there is room to increase their coverage. We focused on four selected non-NIP vaccines in this study, namely Haemophilus influenzae type b (Hib) vaccine, human papillomavirus (HPV) vaccine, pneumococcal conjugate vaccine (PCV), and rotavirus vaccine. We aimed to conduct a scoping review of their vaccination rates and the major barriers faced by health systems, providers, and caregivers to increase coverage.Methods We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR). We searched five English databases (PubMed, Web of Science, EMBASE, Scopus, and WHO IRIS) and four Chinese databases using the search strategy developed by the study team. Two independent reviewers screened, selected studies, and examined their quality. We summarized the non-NIP vaccine coverage data by vaccine and applied the 5A framework (Access, Affordability, Acceptance, Awareness, Activation) to chart and analyze barriers to increasing coverage.Results A total of 28 articles were included in the analysis (nine pertaining to vaccine coverage, and another 19 reporting challenges of increasing uptake). Among the four selected vaccines, coverage for the Hib vaccine was the highest (54.9-55.9% for 1 dose or more from two meta-analyses) in 2016, while the coverage of the other three vaccines was lower than 30%. Eight of the nine included articles mentioned the regional disparity of coverage, which was lower in under-developing regions. For example, the three-dose Hib vaccination rate in eastern provinces was 38.1%, whereas the rate in central and western provinces was 34.3% and 26.2%, respectively in 2017. Within the 5A framework, acceptance, awareness, and affordability stood out as the most prominent themes. Among the 12 identified sub-themes, high prices, low vaccine awareness, concerns about vaccine safety and efficacy were the most cited barriers to increasing the uptake.Conclusions There is an urgent need to increase coverage of non-NIP vaccines and reduce disparities in access to these vaccines across regions. Concerted efforts from the government, the public, and society are required to tackle the barriers and challenges identified in this study, both on the demand and supply side, to ensure everybody has equal access to life-saving vaccines in China. Particularly, the government should take a prudent approach to gradually incorporate non-NIP vaccines into the NIP step by step, and make a prioritizing strategy based on key factors such as disease burden, financial resources, and market readiness, with special attention to high-risk populations and underdeveloped regions.

Leptin immune programming: the assembly key between birth weight and future disease?

The developmental origins for health and disease concept supports that early life environment can affect future health balance and disease.Findings suggest that birthweight(BW)can be a useful indicator of processes that influence long-term health.In fact,there is increasing evidence associating BW with later-life infections,allergy,autoimmune and cancer diseases.To date,there is no common mechanism to explain BW’s direct influence on disease expression during the life cycle.On the other hand,leptin,a circulating hormone,has been pointed as relevant in many disease pathways,including immunological and oncological,and leptin levels seem to vary directly with BW.We suggest that BW could affect early immune programming through variant early-life leptin hormone levels.It is possible that higher leptin levels in higher BW and lower leptin levels in low BW relate to a shift in Th1 and Th2 responses,accounting for different incidences of infections,allergy,autoimmune and cancers,and raising an integrative hypothesis for the effect of BW on future disease.We hope that our hypothesis concerning the possible role of early life leptin levels on immune programming and future disease can be confirmed by experimental data.

Seroconversion of Hepatitis B Vaccine in Young Bangladeshi Children: A Tertiary Centre Experience

Background: Hepatitis B virus (HBV) infection is one of the most important global health problems and active immunization is the single most important and effective preventive measure against HBV infection. Several studied show that HBV carrier rate is between 2% - 7% in Bangladesh. Bangladesh introduced hepatitis B vaccination in children through Expanded Program on Immunization (EPI) in 2005 that includes 3 doses which starts from six weeks after birth. Currently booster vaccination is not recommended any more. However, many studies on different countries observed a declined level of HBs-antibody over a period of 3 - 6 years that may even reach to non-protective levels. Objective: To evaluate the status of seroconversion and seroprotection along with non-responders of EPI vaccinated children against HBV and to measure their antibody levels in different age groups. Methods: A cross sectional descriptive study was done in the department of Pediatric Gastroenterology, Hepatology & Nutrition, Dhaka Shishu (Children) Hospital, Dhaka, Bangladesh on 120 cases of EPI vaccinated children enrolled from January-December 2019 while attending the inpatient department without any liver problem. The development of Anti-HBs titre greater than or equal to 10 mIU/mL is considered as protective immunity and any titre less than 10 mIU/mL as non-protective following HBV vaccination. Results: Age of the children was 1 - 12 years with mean age of 5.6 ± 1.7 years and male: female ratio was 1.1:1. Among the children, 56 (46.6%) were from 1 - 5 years age, 36 (30.1%) children from 6 - 10 years age group and 27 (23.3%) children from 11 - 12 years age group. Out of 120 children, presence of Anti-HBs protective titre was in 63 (52.5%) children and non-protective level in 57 (47.5%) children. Among protective level, 34 (60.7%) children were in 1 - 5 years age group, 18 (50.0%) children in 6 - 10 years age group and 11 (39.3%) children in 11 - 12 years age group. Total 24 (20%) children were completely non-responder (antibody titre 0.00 mIU/mL). Out of 120 mother, 06 (5%) were HBV positive. Among them 05 (83.33%) children had Anti-HBs less than 10 mIU/mL. Conclusion: After primary vaccination, a good immune response was detected against hepatitis B virus but it goes below even up to non-protective level with the increase of age. Half of the studied children had non-protective titre after 5 years and one-fifth children totally non-responder after primary hepatitis B vaccination. A booster dose may be recommended after 5 years for optimum seroprotection.

Immunization coverage,knowledge,satisfaction,and associated factors of non-National Immunization Program vaccines among migrant and left-behind families in China:evidence from Zhejiang and Henan provinces

Background Migrant and left-behind families are vulnerable in health services utilization,but little is known about their disparities in immunization of non-National Immunization Program(NIP)vaccines.This study aims to evaluate the immunization coverage,knowledge,satisfaction,and associated factors of non-NIP vaccines among local and migrant families in the urban areas and non-left-behind and left-behind families in the rural areas of China.Methods A cross-sectional survey was conducted in urban areas of Zhejiang and rural areas of Henan in China.A total of 1648 caregivers of children aged 1-6 years were interviewed face-to-face by a pre-designed online questionnaire,and their families were grouped into four types:local urban,migrant,non-left-behind,and left-behind.Non-NIP vaccines includedHemophilus influenza b(Hib)vaccine,varicella vaccine,rotavirus vaccine,enterovirus 71 vaccine(EV71)and 13-valent pneumonia vaccine(PCV13).Log-binomial regression models were used to calculate prevalence ratios(PRs)and 95%confidence intervals(CIs)for the difference on immunization coverage of children,and knowledge and satisfaction of caregivers among families.The network models were conducted to explore the interplay of immunization coverage,knowledge,and satisfaction.Logistic regression models with odds ratios(ORs)and 95%CIs were used to estimate the associated factors of non-NIP vaccination.Results The immunization coverage of all non-NIP vaccines and knowledge of all items of local urban families was the highest,followed by migrant,non-left-behind and left-behind families.Compared with local urban children,thePRs(95%CIs)for getting all vaccinated were 0.65(0.52-0.81),0.29(0.22-0.37)and 0.14(0.09-0.21)among migrant children,non-left-behind children and left-behind children,respectively.The coverage-knowledge-satisfaction network model showed the core node was the satisfaction of vaccination schedule.Non-NIP vaccination was associated with characteristics of both children and caregivers,including age of children(>2 years-OR:1.69,95%CI:1.07-2.68 for local urban children;2.67,1.39-5.13 for migrant children;3.09,1.23-7.76 for non-left-behind children);and below caregivers’characteristics:family role(parents:0.37,0.14-0.99 for non-left-behind children),age(≤35 years:7.27,1.39-37.94 for non-left-behind children),sex(female:0.49,0.30-0.81 for local urban children;0.31,0.15-0.62 for non-left-behind children),physical health(more than average:1.58,1.07-2.35 for local urban children)and non-NIP vaccines knowledge(good:0.45,0.30-0.68 for local urban children;7.54,2.64-21.50 for left-behind children).Conclusions There were immunization disparities in non-NIP vaccines among migrant and left-behind families compared with their local counterparts.Non-NIP vaccination promotion strategies,including education on caregivers,and optimization of the immunization information system,should be delivered particularly among left-behind and migrant families.

Factors associated with recommendation behaviors of four non-National Immunization Program vaccines:a cross-sectional survey among public health workers in China

Background Immunization is a crucial preventive measure to safeguard children under five years old against a range of diseases.In China,the coverage rate of non-National Immunization Program(non-NIP)vaccines can be improved by leveraging the recommendation from public health workers.Hence,understanding the influencing factors of recommendation behaviors assume paramount importance.This study aims to investigate influencing factors of public health workers’recommendation behaviors towards non-NIP vaccines,with a particular emphasis on financial incentives.Methods A cross-sectional survey was conducted using a multi-stage sampling method in 2019 from August to October.627 public health workers were recruited from 148 community healthcare centers in ten provincial-level administrative divisions in China.An anonymous questionnaire was used to collect demographic information,attitudes towards vaccination,and recommendation behaviors towards non-NIP vaccines,includingHaemophilus influenzae type b(Hib)vaccine,pneumococcal conjugate vaccine,varicella vaccine,and rotavirus vaccine.Descriptive analysis and multivariate logistic regression analysis were adopted in this study.Results Of the 610 public health workers with complete survey data,53.8%,57.4%,84.1%,and 54.1%often recommended Hib vaccine,pneumococcal pneumonia vaccine(PCV),varicella vaccine,and rotavirus vaccine,respectively.Logistic regression revealed that gender(Hib vaccine:OR=0.4,95%CI:0.2-0.8;PCV:OR=0.4,95%CI:0.2-0.8;rotavirus vaccine:OR=0.3,95%CI:0.2-0.6),financial incentives for non-NIP vaccination(Hib vaccine:OR=1.9,95%CI:1.1-3.6;PCV:OR=2.1,95%CI:1.1-3.9;rotavirus vaccine:OR=2.0,95%CI:1.1-3.8)and perception of vaccine safety(Hib vaccine:OR=2.7,95%CI:1.1-7.0;PCV:OR=3.2,95%CI:1.2-8.0;rotavirus vaccine:OR=3.0,95%CI:1.2-7.7)were associated with public health workers’recommendation towards Hib vaccine,PCV and rotavirus vaccine.Conclusions The findings highlighted public health workers’recommendation behaviors of non-NIP vaccines in China and revealed strong association between vaccine recommendation and financial incentives.This highlights the importance of financial incentives in public health workers’recommendation toward non-NIP vaccines in China.Proper incentives are recommended for public health workers to encourage effective health promotion in immunization practices.

Accelerating into Immunization Agenda 2030 with momentum from China’s successful COVID-19 vaccination campaign during dynamic COVID Zero

China’s immunization programs conducted a unified,tightly coordinated COVID-19 vaccination campaign during the dynamic COVID Zero period that reached well over 90%of the population with vaccines having>90%effectiveness against serious-to-fatal COVID-19.The campaign was eight times the size of the annual routine national immunization program,administering 3.4 billion doses of vaccines while monitoring vaccine coverage,acceptability,safety,and effectiveness.Every asset of the routine immunization program had to be strengthened and expanded to attain high coverage and reach hundreds of millions of adults who had not been vaccinated since childhood.Program strengthening and expansion were in directions aligned with the World Health Organization’s Immunization Agenda 2030,which has a vision that"everyone,everywhere,at every age fully benefits from vaccines for good health and well-being"and requires reaching all children,adolescents,and adults with lifesaving vaccines.Momentum from this campaign should not be lost but should be invested into achieving what is possible with a properly resourced national immunization program that is now proven to be capable of reaching everyone in the world’s largest country throughout the life course,and to do so with all vaccines recommended by the World Health Organization.

Impact of the national hepatitis B immunization program in China:a modeling study

Background:Elimination of hepatitis B virus(HBV)is a striking challenge for countries with high or moderate disease burden.Therefore,using China as a practical case to share experiences for similar countries may accelerate the achievement of the WHO 2030 target of 90%reduction in HBV-related incidence.We aim to evaluate the impact of national HBV immunization strategies in China;and the feasibility to achieve WHO 2030 targets under diferent scenarios.Methods:We constructed an expanded Susceptible-Exposed-Infectious-Recovered(SEIR)model and decision treeMarkov model to estimate the epidemic of HBV in China,assess the feasibility of 2030 Elimination Goals through the projections and conduct the economic analysis.Least square method was used to calibrate the expanded SEIR model by yearly data of laboratory-confrmed HBV cases from 1990 to 2018.Two models were separately used to evaluate the impact and cost-efectiveness of HBV vaccine by comparing prevalence of chronic HBV infections,qualityadjusted life-years(QALYs),incremental cost efectiveness ratio and beneft–cost ratio(BCR)under various intervention options,providing a basis for exploring new containment strategies.Results:Between 1990 and 2020,the number of chronic HBV infections decreased by 33.9%.The current status quo would lead to 55.73 million infections(3.95%prevalence)in 2030,compared to 90.63 million(6.42%prevalence)of the“Without the NIP”scenario(NIP:National Immunization Program),114.78 million(8.13%prevalence)without any interventions.The prevention of mother to child transmission(PMTCT)strategy showed a net beneft as 12,283.50 dollars per person,with BCR as 12.66,which is higher than that of universal vaccination at 9.49.Compared with no screening and no vaccination,the PMTCT strategy could save 7726.03 dollars for each QALY increase.Conclusions:Our fndings proved the HBV vaccination has demonstrated a substantial positive impact on controlling the epidemic of HBV in terms of efectiveness and economy after about 30 years of implementation of the national hepatitis B immunization program which also provided containment experience for high or medium burden countries.As for China,the next step should focus on exploring strategies to improve diagnosis and treatment coverage to reduce the burden of HBV-related deaths and ultimately eliminate HBV.

Improving immunization capacity in Ethiopia through continuous quality improvement interventions:a prospective quasi-experimental study

Background:Strong scientific evidence is needed to support low-income countries in building effective and sustainable immunization programs and proactively engaging in global vaccine development and implementation initiatives.This study aimed to implement and evaluate the effectiveness of system-wide continuous quality improvement(CQI)interventions to improve national immunization programme performance in Ethiopia.Methods:The study used a prospective,quasi-experimental design with an interrupted time-series analysis to collect data from 781 government health sectors(556 healthcare facilities,196 district health offices,and 29 zonal health departments)selected from developing and emerging regions in Ethiopia.Procedures included baseline quality assessment of immunization programme and services using structured checklists;immunization systems strengthening using onsite technical support,training,and supportive supervision interventions in a Plan-Do-Check-Act cycle over 12 months;and collection and analysis of data at baseline and at the 6th and 12th month of interventions using statistical process control and the t-test.Outcome measures were the coverage of the vaccines pentavalent 3,measles,Bacillus Calmette-Guérin vaccine(BCG),Pneumococcal Conjugate Vaccine(PCV),as well as full vaccination status;while process measures were changes in human resources,planning,service delivery,logistics and supply,documentation,coordination and collaboration,and monitoring and evaluation.Analysis and interpretation of data adhered to SQUIRE 2.0 guidelines.Results:Prior to the interventions,vaccination coverage was low and all seven process indicators had an aggregate score of below 50%,with significant differences in performance at healthcare facility level between developing and emerging regions(P=0.0001).Following the interventions,vaccination coverage improved significantly from 63.6%at baseline to 79.3%for pentavalent(P=0.0001),62.5 to 72.8%for measles(P=0.009),62.4 to 73.5%for BCG(P=0.0001),65.3 to 81.0%for PCV(P=0.02),and insignificantly from 56.2 to 74.2%for full vaccination.All seven process indicators scored above 75%in all regions,with no significant differences found in performance between developing and emerging regions.Conclusions:The CQI interventions improved immunization capacity and vaccination coverage in Ethiopia,where the unstable transmission patterns and intensity of infectious diseases necessitate for a state of readiness of the health system at all times.The approach was found to empower zone,district,and facility-level health sectors to exercise accountability and share ownership of immunization outcomes.While universal approaches can improve routine immunization,local innovative interventions that target local problems and dynamics are also necessary to achieve optimal coverage.