Immunisation coverage and factors associated with incomplete immunisation in children under two during the COVID-19 pandemic in Sierra Leone.

BACKGROUND: Routine childhood immunisation is one of the most important life-saving public health interventions. However, many children still have inadequate access to these vaccines and millions remain (partially) unvaccinated globally. As the COVID-19 pandemic disrupted health systems worldwide, its effects on immunisation have become apparent. This study aimed to estimate routine immunisation coverage among children under two in Sierra Leone and to identify factors associated with incomplete immunisation during the COVID-19 pandemic. METHODS: A cross-sectional household survey was conducted in three districts in Sierra Leone: Bombali, Tonkolili and Port Loko. A three-stage cluster sampling method was followed to enrol children aged 10-23 months. Information regarding immunisation status was based on vaccination cards or caretaker's recall. Using WHO's definition, a fully immunised child received one BCG dose, three oral polio vaccine doses, three pentavalent vaccine doses and one measles-containing vaccine dose. Following the national schedule, full immunisation status can be achieved at 9 months of age. Data were weighted to reflect the survey's sampling design. Associations between incomplete immunisation and sociodemographic characteristics were assessed through multivariable logistic regression. RESULTS: A total of 720 children were enrolled between November and December 2021. Full vaccination coverage was estimated at 65.8% (95% CI 60.3%-71.0%). Coverage estimates were highest for vaccines administered at birth and decreased with doses administered subsequently. Adjusting for age, the lowest estimated coverage was 40.7% (95% CI 34.5%-47.2%) for the second dose of the measles-containing vaccine. Factors found to be associated with incomplete immunisation status were: living in Port Loko district (aOR = 3.47, 95% CI = 2.00-6.06; p-value < 0.001), the interviewed caretaker being Muslim (aOR = 1.94, 95% CI = 1.25-3.02; p-value = 0.015) and the interviewed caretaker being male (aOR = 1.93, 95% CI = 1.03-3.59, p-value = 0.039). CONCLUSION: Though full immunisation coverage at district level improved compared with pre-pandemic district estimates from 2019, around one in three surveyed children had missed at least one basic routine vaccination and over half of eligible children had not received the recommended two doses of a measles-containing vaccine. These findings highlight the need to strengthen health systems to improve vaccination uptake in Sierra Leone, and to further explore barriers that may jeopardise equitable access to these life-saving interventions.

Correlation between measles vaccine doses: implications for the maintenance of elimination.

Measles eradication efforts have been successful at achieving elimination in many countries worldwide. Such countries actively work to maintain this elimination by continuing to improve coverage of two routine doses of measles vaccine following measles elimination. While improving measles vaccine coverage is always beneficial, we show, using a steady-state analysis of a dynamical model, that the correlation between populations receiving the first and second routine dose also has a significant impact on the population immunity achieved by a specified combination of first and second dose coverage. If the second dose is administered to people independently of whether they had the first dose, high second-dose coverage improves the proportion of the population receiving at least one dose, and will have a large effect on population immunity. If the second dose is administered only to people who have had the first dose, high second-dose coverage reduces the rate of primary vaccine failure, but does not reach people who missed the first dose; this will therefore have a relatively small effect on population immunity. When doses are administered dependently, and assuming the first dose has higher coverage, increasing the coverage of the first dose has a larger impact on population immunity than does increasing the coverage of the second. Correlation between vaccine doses has a significant impact on the level of population immunity maintained by current vaccination coverage, potentially outweighing the effects of age structure and, in some cases, recent improvements in vaccine coverage. It is therefore important to understand the correlation between vaccine doses as such correlation may have a large impact on the effectiveness of measles vaccination strategies.

An assessment of the geographical risks of wild and vaccine-derived poliomyelitis outbreaks in Africa and Asia.

BACKGROUND: The international spread of wild poliomyelitis outbreaks continues to threaten eradication of poliomyelitis and in 2014 a public health emergency of international concern was declared. Here we describe a risk scoring system that has been used to assess country-level risks of wild poliomyelitis outbreaks, to inform prioritisation of mass vaccination planning, and describe the change in risk from 2014 to 2016. The methods were also used to assess the risk of emergence of vaccine-derived poliomyelitis outbreaks. METHODS: Potential explanatory variables were tested against the reported outbreaks of wild poliomyelitis since 2003 using multivariable regression analysis. The regression analysis was translated to a risk score and used to classify countries as Low, Medium, Medium High and High risk, based on the predictive ability of the score. RESULTS: Indicators of population immunity, population displacement and diarrhoeal disease were associated with an increased risk of both wild and vaccine-derived outbreaks. High migration from countries with wild cases was associated with wild outbreaks. High birth numbers were associated with an increased risk of vaccine-derived outbreaks. CONCLUSIONS: Use of the scoring system is a transparent and rapid approach to assess country risk of wild and vaccine-derived poliomyelitis outbreaks. Since 2008 there has been a steep reduction in the number of wild poliomyelitis outbreaks and the reduction in countries classified as High and Medium High risk has reflected this. The risk of vaccine-derived poliomyelitis outbreaks has varied geographically. These findings highlight that many countries remain susceptible to poliomyelitis outbreaks and maintenance or improvement in routine immunisation is vital.

Influence of the COVID-19 pandemic on caregiver beliefs and experiences of routine childhood immunisation in Indonesia.

The COVID-19 pandemic contributed to significant health services declines in South-East Asia including Indonesia, which experienced a decline in routine immunisation of children. This study investigated the influence of the pandemic on the beliefs and experiences of caregivers of children related to routine immunisation. This study involved a cross-sectional survey among 1399 caregivers of children aged 0-24 months in Central Java and West Nusa Tenggara provinces from March-April 2022. Data on beliefs and experiences of childhood immunizations were captured using core items from the WHO/UNICEF Behavioural and Social Drivers of Immunization (BeSD) survey. Bivariate and multivariate logistic regression analyses identified factors associated with uptake of routine immunisations. While nearly all caregivers (95.7%) reported wanting their child to receive all recommended routine immunisations, only 40.3% of children aged 2-24 months were up-to-date with all vaccines for age. Factors associated with up-to-date included higher parental education (aOR: 1.76, 95% CI 1.02-3.05), higher household income (aOR: 1.54, 95% CI 1.09-2.18), and caregivers who found it moderately or very easy to get immunisations (aOR: 2.26/2.22, 95% CI 1.06-4.83/1.06-4.69). Recovery efforts should prioritise responding to the factors associated with immunisation status (e.g., perceived ease of access) and on families experiencing disadvantage (e.g., caregivers with lower education and household income) to ensure protections against future outbreaks that are responsive to the context-specific needs and priorities of districts and communities.

Factors associated with hepatitis B vaccination in Laos: findings from the multiple indicator cluster surveys in 2011/12 and 2017.

Background: Within Laos, the vaccination coverage rates with the monovalent hepatitis B birth dose vaccine and hepatitis B antigen-containing combination vaccines remain stagnant with 75% and 64%, respectively, in 2021. In this study, we used data from the Multiple Indicator Cluster Surveys to identify possible factors that represent barriers for receiving these childhood vaccinations. Methods: Data from the Multiple Indicator Cluster Surveys in 2011/12 and 2017 were analysed to examine factors associated with receiving the hepatitis B-containing vaccines using regression modelling. Data analyses were conducted in R. Findings: In 2011/12, the weight-adjusted coverage rate for receiving the hepatitis B birth dose was 48%, while the coverage with the hepatitis B antigen-containing combination vaccine was 55.1% based on both vaccination documents and recall; compared to 69.3% and 59.4% respectively in 2017. Ethno-linguistic group, maternal education, healthcare utilization and wealth were associated with receiving the vaccinations against hepatitis B. Interpretation: National estimates of vaccination coverage rates can conceal country-specific regional or socio-economic variations. Children from Hmong-Mien households, from less wealthier households and whose mothers were less educated and were not able to or did not utilize healthcare were identified as being less likely to receive the vaccinations. These findings indicate the need for improving access to healthcare, in particular for minority groups. Funding: This work was supported by the Ministry of Foreign and European Affairs, Luxembourg and the Luxembourg Institute of Health (project "Luxembourg-Laos Partnership for Research and Capacity Building in Infectious Disease Surveillance").

UK healthcare professionals' attitudes towards the introduction of varicella vaccine into the routine childhood vaccination schedule and their preferences for administration.

BACKGROUND: Varicella (chickenpox) is a highly contagious disease caused by the varicella-zoster virus. Although typically mild, varicella can cause complications leading to severe illness and even death. Safe and effective varicella vaccines are available. The Joint Committee on Vaccination and Immunisation has reviewed the evidence and recommended the introduction of varicella vaccine into the UK's routine childhood immunisation schedule. OBJECTIVES: To explore UK healthcare professionals' (HCPs) knowledge and attitudes towards varicella vaccination, its introduction to the UK routine childhood immunisation schedule, and their preferences for how it should be delivered. DESIGN: We conducted an online cross-sectional survey exploring HCPs' attitudes towards varicella, varicella vaccine, and their preferences for delivery of the vaccine between August and September 2022 prior to the recommendation that varicella vaccine should be introduced. PARTICIPANTS: 91 HCPs working in the UK (81 % nurses/health visitors, 9 % doctors, 10 % researcher/other, mean age 48.7 years). RESULTS: All respondents agreed or strongly agreed that vaccines are important for a child's health. However, only 58% agreed or strongly agreed that chicken pox was a disease serious enough to warrant vaccination. Gaps in knowledge about varicella were revealed: 21.0% of respondents disagreed or were unsure that chickenpox can cause serious complications, while 41.8% were unsure or did not believe chickenpox was serious enough to vaccinate against. After receiving some basic information about chickenpox and the vaccine, almost half of the HCPs (47.3%) in our survey would prefer to administer the varicella vaccine combined with MMR. CONCLUSIONS: Given the positive influence of HCPs on parents' decisions to vaccinate their children, it is important to understand HCPs' views regarding the introduction of varicella vaccine into the routine schedule. Our findings highlighted areas for training and HCPs' preferences which will have implications for policy and practice when the vaccine is introduced.

Parental acceptance of and preferences for administration of routine varicella vaccination in the UK: A study to inform policy.

OBJECTIVES: To explore acceptability of and preferences for the introduction of varicella vaccination to the UK childhood immunisation schedule. DESIGN: We conducted an online cross-sectional survey exploring parental attitudes towards vaccines in general, and varicella vaccine specifically, and their preferences for how the vaccine should be administered. PARTICIPANTS: 596 parents (76.3% female, 23.3% male, 0.4% other; mean age 33.4 years) whose youngest child was aged 0-5 years. MAIN OUTCOME MEASURES: Willingness to accept the vaccine for their child and preferences for how the vaccine should be administered (in combination with the MMR vaccine [MMRV], on the same day as the MMR vaccine but as a separate injection [MMR + V], on a separate additional visit). RESULTS: 74.0% of parents (95% CI 70.2% to 77.5%) were extremely/somewhat likely to accept a varicella vaccine for their child if one became available, 18.3% (95% CI 15.3% to 21.8%) were extremely/somewhat unlikely to accept it and 7.7% (95% CI 5.7% to 10.2%) were neither likely nor unlikely. Reasons provided by parents likely to accept the vaccine included protection from complications of chickenpox, trust in the vaccine/healthcare professionals, and wanting their child to avoid their personal experience of chickenpox. Reasons provided by parents who were unlikely included chickenpox not being a serious illness, concern about side effects, and believing it is preferable to catch chickenpox as a child rather than as an adult. A combined MMRV vaccination or additional visit to the surgery were preferred over an additional injection at the same visit. CONCLUSIONS: Most parents would accept a varicella vaccination. These findings highlight parents' preferences for varicella vaccine administration, information needed to inform vaccine policy and practice and development of a communication strategy.

Analysis of global routine immunisation coverage shows disruption and stagnation during the first two-years of the COVID-19 pandemic with tentative recovery in 2022.

Whilst it is now widely recognised that routine immunisation (RI) was disrupted by the COVID-19 pandemic in 2020, and further so in 2021, the extent of continued interruptions in 2022 and/or rebounds to previous trends remains unclear. We modelled country-specific RI trends using validated estimates of national coverage from the World Health Organisation and United Nation Children's Fund for 182 countries (accounting for > 97% of children globally), to project expected diphtheria, tetanus, and pertussis-containing vaccine first-dose (DTP1), third-dose (DTP3) and measles-containing vaccine first-dose (MCV1) coverage for 2020-2022 based on pre-pandemic trends (from 2000 to 2019). We provide further evidence of peak pandemic immunisation disruption in 2021, followed by tentative recovery in 2022. We report a 3.4% (95 %CI: [2.5%; 4.4%]) decline in global DTP3 coverage in 2021 compared to 2000-2019 trends, from an expected 89.8% to reported 86.4%. This coverage gap reduced to a 2.7% (95 %CI: [1.8%; 3.6%]) decline in 2022, with reported coverage rising to 87.2%. Similar results were seen for DTP1 and MCV1. Whilst partial rebounds are encouraging, global coverage decline translates to a 17-year setback in RI to 2005 levels, and the majority of countries retain coverage at or lower than pre-pandemic levels. The Americas, Africa, and Asia were the most impacted regions; and low- and middle-income countries the most affected income groups. The number of annual Zero Dose (ZD) children - indicating those receiving no immunisations - increased from 12.1 million (M) globally in 2019 to a peak of 16.7 M in 2021, then reduced to 13.1 M in 2022. Overall, we estimate an excess of 8.8 M ZD children cumulatively in 2020-2022 compared to pre-pandemic levels. This work can be used as an objective baseline to inform future interventions to prioritise and target interventions, and facilitate catch-up of growing populations of under- and un-immunised children.

Worldwide routine immunisation coverage regressed during the first year of the COVID-19 pandemic.

Whilst COVID-19 vaccination strategies continue to receive considerable emphasis worldwide, the extent to which routine immunisation (RI) has been impacted during the first year of the pandemic remains unclear. Understanding the existence, extent, and variations in RI disruptions globally may help inform policy and resource prioritisation as the pandemic continues. We modelled historical, country-specific RI trends using publicly available vaccination coverage data for diphtheria, tetanus and pertussis-containing vaccine first-dose (DTP1) and third-dose (DTP3) from 2000 to 2019. We report a 2·9% (95 %CI: [2·2%; 3·6%]) global decline in DTP3 coverage from an expected 89·2% to a reported 86·3%; and a 2·2% decline in DTP1 coverage (95 %CI: [1·6%; 2·8%]). These declines translate to levels of coverage last observed in 2005, thus suggesting a potential 15-years setback in RI improvements. Further research is required to understand which factors - e.g., health seeking behaviours or non-pharmaceutical interventions - linked to the COVID-19 crisis impacted vaccination coverage.

Examining enablers of vaccine hesitancy toward routine childhood and adolescent vaccination in Malawi.

BACKGROUND: The contribution of vaccination to global public health and community wellbeing has been described as one of the greatest success stories of modern medicine. However, 13.5 million children still miss at least one of their routine vaccinations, and this contributes to about 1.5 million deaths from vaccine-preventable diseases. One of the contributing factors has been associated with vaccine hesitancy. Vaccine hesitancy is the delay or refusal of vaccines despite their availability. The study explored factors from multiple perspectives that influence hesitancy among caregivers of children and adolescent girls eligible for childhood routine immunisation and the Human Papillomavirus vaccine in Malawi. METHODS: The methodology used was qualitative such as key informant interviews and focus-group discussion. Information was obtained from caregivers, community and religious leaders, leaders of civil society groups, teachers in schools where Human Papillomavirus vaccine were piloted, healthcare workers, national and district-level officials of the expanded program on immunisation. There were 25 key informant interviews and two focus-group discussions, with 13 participants. The study was conducted between April to May 2020. The Interviews and discussions were audio-recorded, transcribed, and analysed using a thematic content approach. RESULTS: Most vaccine-hesitancy drivers for routine immunisation were also relevant for the HPV vaccine. The drivers included inadequate awareness of the vaccination schedule, rumours and conspiracy theories exacerbated by religious beliefs, low literacy levels of caregivers, distance and transport to the vaccination clinic, gender role and a disconnect between community healthcare workers and community leaders. CONCLUSIONS: The study demonstrated that a network of factors determines vaccine hesitancy for childhood Routine Immunisation and Human Papillomavirus, and some of them are interrelated with one another. This has implications both for current levels of vaccine acceptance and the introduction of any new vaccine, such as those against Malaria, HIV/AIDS, HPV or COVID-19 (coronavirus disease 2019). Therefore, strategies developed to address vaccine hesitancy must be multi-component and wide-ranging.

Polio eradication in a chronic conflict setting lessons from the Republic of South Sudan, 2010-2020.

Introduction: in 1988 the World Health Assembly set an ambitious target to eradicate Wild Polio Virus (WPV) by 2000, following the successful eradication of the smallpox virus in 1980. South Sudan and the entire African region were certified WPV free on August 25, 2020. South Sudan has maintained its WPV free status since 2010, and this paper reviewed the country's progress, outlined lessons learned, and describes the remaining challenges in polio eradication. Methods: secondary data analysis was conducted using the Ministry of Health and WHO polio surveillance datasets, routine immunisation coverage, polio campaign data, and surveys from 2010 to 2020. Relevant technical documents and reports on polio immunisation and surveillance were also reviewed. Data analysis was conducted using EPI Info 7 software. Results: administrative routine immunisation coverage for bivalent Oral Polio Vaccine (OPV) 3rd dose declined from 77% in 2010 to 56% in 2020. In contrast, the administrative and post-campaign evaluation coverage recorded for the nationwide supplemental polio campaigns since 2011 was consistently above 85%; however, campaigns declined in number from four in 2011 to zero in 2020. Overall, 76% of notified cases of Acute Flaccid Paralysis (AFP) received three or more doses of the oral polio vaccine. The Annualized Non-AFP rate ranged between 4.0 to 5.4 per 100,000 under 15 years populations, and stool adequacy ranged from 83% to 94%. Conclusion: South Sudan's polio-free status documentation was accepted by the ARCC in 2020, thereby enabling the African Region to be certified WPV free on August 25, 2020. However, there are concerns as the country continues to report low routine immunisation coverage and a reduction in the number of polio campaigns conducted each year. It is recommended that the country conduct high-quality nationwide supplemental polio campaigns yearly to achieve and maintain the required herd immunity. It invests in its routine immunisation program while ensuring optimal AFP surveillance performance indicators.

Potential for improving routine immunisation waste management using measles vaccination campaign 2017 in Kebbi State, Nigeria.

BACKGROUND: Immunisation activities generate sharps and infectious non-sharp waste that have harmful impact on the community and health care workers if disposed of improperly, leading to carbon mono oxide (CO) emissions which contribute to global warming. Health care waste is not effectively managed, especially in some developing countries. However, measles supplemental immunisation activities (SIAs) are used to strengthen routine immunisation system, including waste management. The waste management planning provides an opportunity to build capacity, mobilize resources and strengthen structures to ensure continual disposal of routine immunisation waste. METHODS: We reviewed the Kebbi State and LGA routine immunisation waste management situation and identified existing gaps; developed and implemented the plan for waste management, including strengthening routine immunisation waste management. The process included, reactivation of measles technical coordination committee, mobilizing resources for funding, and sustenance of immunisation waste management. The health care workforce was trained in safe immunisation waste disposal practices. RESULTS: Immunisation waste management committee and the structure was established and strengthened at the state and LGA levels and a total cost of 11,710.70 USD was expended on injection waste management, with an average cost per injection of 0.01 USD. A total of 11,829 safety boxes were incinerated in the state, including those generated from routine immunisation sessions. Twenty-one Local Immunisation Officers, 1097 and 2192 team supervisors and healthcare worker vaccinators respectively were trained on immunisation waste disposal. CONCLUSION: Immunisation waste management strategies protect healthcare workers and reduce the adverse impact on the environment. Improving key areas such as human and financial resources ensures accountability towards sustainable healthcare waste management.

The impact of maternal health care utilisation on routine immunisation coverage of children in Nigeria: a cross-sectional study.

OBJECTIVE: To examine the impact of maternal healthcare (MHC) utilisation on routine immunisation coverage of children in Nigeria. DESIGN: Individual level cross-sectional study using bivariate and multivariable logistic regression analyses to examine the association between MHC utilisation and routine immunisation coverage of children. SETTING: Nigeria Demographic and Health Survey 2013. PARTICIPANTS: 5506 women aged 15-49 years with children aged 12-23 months born in the 5 years preceding the survey. PRIMARY OUTCOME MEASURES: Fully immunised children and not fully immunised children. RESULTS: The percentage of children fully immunised with basic routine childhood vaccines by the age of 12 months was 25.8%. Antenatal care (ANC) attendance irrespective of the number of visits (adjusted OR (AOR)1-3 visits 2.4, 95% CI 1.79 to 3.27; AOR4-7 visits 3.2, 95% CI 2.52 to 4.13; AOR≥ 8 visits 3.5, 95% CI 2.64 to 4.50), skilled birth attendance (SBA) (AOR 1.9, 95% CI 1.65 to 2.35); and maternal postnatal care (PNC) (AOR 1.7, 95% CI 1.46 to 2.06) had positive effects on the child being fully immunised after adjusting for covariates (except for each other, ie, ANC, SBA and PNC). Further analyses (adjusting stepwise for each MHC service) showed a mediation effect that led to the effect of PNC not being significant. CONCLUSIONS: The percentage of fully immunised children in Nigeria was very low. ANC attendance, SBA and maternal PNC attendance had positive impact on the child being fully immunised. The findings suggest that strategies aimed at maximising MHC utilisation in Nigeria could be effective in achieving the national coverage target of at least 80% for routine immunisation of children.

A pilot study of routine immunization data quality in Bunza Local Government area: causes and possible remedies.

INTRODUCTION: As a result of poor quality administrative data for routine immunisation (RI) in Nigeria, the real coverage of RI remains unknown, constituting a setback in curtailing vaccine preventable diseases (VPDs). Consequently, the purpose of this pilot study is to identify source(s) and evaluate the magnitude of poor data quality as well as propose recommendations to address the problem. METHODS: The authors conducted a cross-sectional study in which 5 out of the 22 health facilities providing routine immunization services in Bunza Local Government Area (LGA), Kebbi State, Nigeria, were selected for data quality assessment. The reported coverage of RI in August and September, 2016 was the primary element of evaluation in the selected Health Facilities (HFs). Administered questionnaires were adapted from WHO Data Quality Assurance and RI monitoring tools to generate data from the HFs, as well as standardised community survey tool for household surveys. RESULTS: Data inconsistency was detected in 100% of the selected HFs. Maximum difference between HF monthly summary and RI registration book for penta 3 data quality report analysis was 820% and 767% in MCH Bunza and PHC Balu respectively. However, a minimum difference of 3% was observed at Loko Dispensary. Maximum difference between HF summary and RI registration for measles was 614% at MCH Bunza and 43% minimum difference at Loko. In contrast to the administrative coverage, 60-80% of the children sampled from households were either not immunised or partially immunised. Further, the main sources of poor data quality include heavy workload on RI providers, over-reliance on administrative coverage report, and lack of understanding of the significance of high data quality by RI providers. CONCLUSION: Substantial data discrepancies were observed in RI reports from all the Health Facilities which is indicative of poor data quality at the LGA level. Community surveys also revealed an over-reporting from administrative coverage data. Consequently, efforts should be geared towards achieving good data quality by immunisation stakeholders as it has implication on disease prevention and control efforts.

Comparison of school based and supplemental vaccination strategies in the delivery of vaccines to 5-19 year olds in Africa - a systematic review.

BACKGROUND: Some vaccine preventable diseases (VPDs) still remain a public health burden in many African countries. The occurrence of VPDs in all age groups has led to the realization of the need to extend routine immunisation services to school age children, adolescents and adults. Supplemental immunisation activities (SIAs) and school based vaccinations (SBVs) are common strategies used to complement the expanded programme on immunisation (EPI). This review aimed to assess the effectiveness of SIAs compared to SBVs in the administration of vaccines to 5-19 year olds in Africa. METHODS: Systematic review methods were used to address our study aim. Several electronic databases were searched up to March 30, 2017 for primary studies investigating the delivery of vaccines via SIAs or SBVs to 5-19 year olds. This search was complemented by browsing reference lists of potential studies obtained from search outputs. Outcomes considered for inclusion were: vaccination coverage, costs of the strategy or its effect on routine immunisation services. RESULTS: Out of the 4938 studies identified, 31 studies met the review inclusion criteria. Both SIAs and SBVs showed high vaccination coverage. However, the SIAs reported higher coverage than SBVs: 91% (95% CI: 84%, 98%) versus 75% (95% CI: 67%, 83%). In most settings, SBVs were reported to be more expensive than SIAs. The SIAs were found to negatively affect routine immunisation services. CONCLUSIONS: Both SIAs and SBVs are routinely used to complement the EPI in the delivery of vaccines in Africa. In settings where school enrolment is suboptimal, as is the case in many African countries, our results show SIAs may be more effective in reaching school age children and adolescents than SBVs. Our results re-iterate the importance of evaluating systematic evidence to best inform African authorities on the optimal vaccine delivery strategies targeting school age children and adolescents.

Determinants of immunisation coverage of children aged 12-59 months in Indonesia: a cross-sectional study.

OBJECTIVES: Despite the adoption of WHO's Expanded Programme on Immunisation in Indonesia since 1977, a large proportion of children are still completely unimmunised or only partly immunised. This study aimed to assess factors associated with low immunisation coverage of children in Indonesia. SETTING: Children aged 12-59 months in Indonesia. PARTICIPANT: The socioeconomic characteristics and immunisation status of the children were obtained from the most recent Demographic and Health Survey, the 2012 Indonesia Demographic and Health Survey. Participants were randomly selected through a two-stage stratified sampling design. Data from 14 401 children aged 12-59 months nested within 1832 census blocks were included in the analysis. Multilevel logistic regression models were constructed to account for hierarchical structure of the data. RESULTS: The mean age of the children was 30 months and they were equally divided by sex. According to the analysis, 32% of the children were fully immunised in 2012. Coverage was significantly lower among children who lived in Maluku and Papua region (adjusted OR: 1.94; 95% CI 1.42 to 2.64), were 36-47 months old (1.39; 1.20 to 1.60), had higher birth order (1.68; 1.28 to 2.19), had greater family size (1.47; 1.11 to 1.93), whose mother had no education (2.13; 1.22 to 3.72) and from the poorest households (1.58; 1.26 to 1.99). The likelihood of being unimmunised was also higher among children without health insurance (1.16; 1.04 to 1.30) and those who received no antenatal (3.28; 2.09 to 5.15) and postnatal care (1.50; 1.34 to 1.69). CONCLUSIONS: Socioeconomic factors were strongly associated with the likelihood of being unimmunised in Indonesia. Unimmunised children were geographically clustered and lived among the most deprived population. To achieve WHO target of protective coverage, public health interventions must be designed to meet the needs of these high-risk groups.

Cost analysis of routine immunisation in Zambia.

BACKGROUND: This study aimed to inform planning and funding by providing updated, detailed information on total and unit costs of routine immunisation (RI) in Zambia, a GAVI-eligible lower middle-income country with a population of 13 million. METHODS: The exercise was part of a multi-country study on costs and financing of routine immunisation (EPIC) that utilized a common, ingredients-based approach to costing. Data on inputs, prices and outputs were collected in a stratified, random sample of 51 facilities in nine districts between December 2012 and March 2013 using a pre-tested questionnaire. Shared inputs were allocated to RI costs on the basis of tracing factors developed for the study. A comprehensive set of costs were analysed to obtain total and unit costs, at facility and above-facility levels. RESULTS: The total annual economic cost of RI was $38.16 million, equivalent to approximately 10% of government health spending. Government contributed 83% of finances. Labour accounted for the lion's share (49%) of total costs followed by vaccines (16%) and travel allowances (12%). Analysis of specific activity costs showed that outreach and facility-based services accounted for half of total economic costs. Costs for managing the program at district, provincial and national levels (above-facility costs) represented 24% of total costs. Average unit costs were $7.18 per dose, $59.32 per infant and $65.89 per DPT3 immunised child, with markedly higher unit costs in rural facilities. Analyses suggest that greater efficiency is associated with higher utilisation levels and urban facility type. CONCLUSIONS: Total and unit costs, and government's contribution, were considerably higher than previous Zambian estimates and international benchmarks. These findings have substantial implications for planners, efficiency improvement and sustainable financing, particularly as new vaccines are introduced. Variations in immunisation costs at facility level warrant further statistical analyses.