Key Factors to Consider When Introducing a New Vaccine in Low-Income Settings: Lessons from Malawi Expanded Program on Immunization

Introduction: As new vaccines become available, countries must assess the relevance to introduce them into their vaccination schedules. Malawi has recently introduced several new vaccines and plans to introduce more. This study was conducted to identify key factors that need to be considered when deciding to introduce a new vaccine and current challenges faced by low and middle income countries using Malawi as an example. Methodology: The study employed a desk review approach, examining published literature from various sources such as PubMed, Medline, and Google Scholar. Policy documents from organizations like the World Health Organization, GAVI the Alliance, and the Ministry of Health for Malawi were also included. A total of 99 articles and documents on new vaccine introduction, challenges of immunization, policy documents in immunization and health systems strengthening were included. The review focused on addressing five key areas critical to new vaccine introduction namely: the need for a vaccine, availability of the vaccine, safety and effectiveness of the vaccine, demand for the vaccine, and the prudent use of public or private funds. Results: Malawi considered the burden of cervical cancer and the significance of malaria in the country when introducing the HPV and malaria vaccines. The country opted for vaccines that can be handled by the cold chain capacity and available human resources. Despite that malaria vaccine and Typhoid Conjugate Vaccine trials were done in country, there are limited vaccine safety and efficacy trials conducted in Malawi, leading to a reliance on WHO-prequalified vaccines. Demand for newly introduced vaccines varied, with high demand for Oral Cholera Vaccine during a cholera outbreak, while demand for COVID-19 vaccines decreased over time. Although cost-effectiveness studies were limited in the country, 2 studies indicated that Typhoid Conjugate Vaccine and malaria vaccine would be cost effective. All these have been implemented despite having challenges like lack of accurate surveillance data, inadequate cold chain capacity, limited safety and efficacy vaccine clinical trials, political influence, and limited funding. Conclusion: Despite several challenges Malawi set a good example of the careful considerations required before introducing a new vaccine. The process involves data review, priority setting, precise planning, and consultation with stakeholders. Low-income countries should invest in vaccine safety, efficacy, and cost-effectiveness trials.

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.

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.

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.