The influence of compositional and contextual factors on non-receipt of basic vaccines among children of 12-23-month old in India: a multilevel analysis

Inequality in Childhood Immunization Coverage: A Scoping Review of Data Sources, Analyses, and Reporting Methods

Immunization through vaccines among children has contributed to improved childhood survival and health outcomes globally. However, vaccine coverage among children is unevenly distributed across settings and populations. The measurement of inequalities is essential for understanding gaps in vaccine coverage affecting certain sub-populations and monitoring progress towards achieving equity. Our study aimed to characterize the methods of reporting inequalities in childhood vaccine coverage, inclusive of the settings, data source types, analytical methods, and reporting modalities used to quantify and communicate inequality. We conducted a scoping review of publications in academic journals which included analyses of inequalities in vaccination among children. Literature searches were conducted in PubMed and Web of Science and included relevant articles published between 8 December 2013 and 7 December 2023. Overall, 242 publications were identified, including 204 assessing inequalities in a single country and 38 assessing inequalities across more than one country. We observed that analyses on inequalities in childhood vaccine coverage rely heavily on Demographic Health Survey (DHS) or Multiple Indicator Cluster Surveys (MICS) data (39.3%), and papers leveraging these data had increased in the last decade. Additionally, about half of the single-country studies were conducted in low- and middle-income countries. We found that few studies analyzed and reported inequalities using summary measures of health inequality and largely used the odds ratio resulting from logistic regression models for analyses. The most analyzed dimensions of inequality were economic status and maternal education, and the most common vaccine outcome indicator was full vaccination with the recommended vaccine schedule. However, the definition and construction of both dimensions of inequality and vaccine coverage measures varied across studies, and a variety of approaches were used to study inequalities in vaccine coverage across contexts. Overall, harmonizing methods for selecting and categorizing dimensions of inequalities as well as methods for analyzing and reporting inequalities can improve our ability to assess the magnitude and patterns of inequality in vaccine coverage and compare those inequalities across settings and time.

Area and individual level analyses of demographic and socio-economic disparities in COVID-19 vaccination uptake in Belgium

Vaccination has played a major role in overcoming the COVID-19 pandemic. However, vaccination status can be influenced by demographic and socio-economic factors at individual and area level. In the context of the LINK-VACC project, the Belgian vaccine register for the COVID-19 vaccination campaign was linked at individual level with other registers, notably the COVID-19 laboratory test results and demographic and socio-economic variables from the DEMOBEL database. The present article aims at investigating to which extent COVID-19 vaccination status is associated with area level and/or individual level demographic and socio-economic factors. From a sample of all individuals tested for SARS-CoV-2 (LINK-VACC sample) demographic and socio-economic indicators are derived and their impact on vaccination coverages at an aggregated geographical level (municipality) is quantified. The same indicators are calculated for the full Belgian population, allowing to assess the representativeness of the LINK-VACC sample with respect to the impact of demographic and socio-economic disparities on vaccination uptake. In a second step, hierarchical models are fitted to the individual level LINK-VACC data to disentangle the individual and municipality effects allowing to evaluate the added value of the availability of individual level data in this context. The most important effects observed at the individual level are reflected in the aggregated data at the municipality level. Multilevel analyses show that most of the demographic and socio-economic impacts on vaccination are captured at the individual level, although accounting for area level in individual level analyses improve the overall description.

Understanding household-level risk factors for zero dose immunization in 82 low- and middle-income countries

INTRODUCTION

In 2021, an estimated 18 million children did not receive a single dose of routine vaccinations and constitute the population known as zero dose children. There is growing momentum and investment in reaching zero dose children and addressing the gross inequity in the reach of immunization services. To effectively do so, there is an urgent need to characterize more deeply the population of zero dose children and the barriers they face in accessing routine immunization services.

METHODS

We utilized the most recent DHS and MICS data spanning 2011 to 2020 from low, lower-middle, and upper-middle income countries. Zero dose status was defined as children aged 12-23 months who had not received any doses of BCG, DTP-containing, polio, and measles-containing vaccines. We estimated the prevalence of zero-dose children in the entire study sample, by country income level, and by region, and characterized the zero dose population by household-level factors. Multivariate logistic regressions were used to determine the household-level sociodemographic and health care access factors associated with zero dose immunization status. To pool multicountry data, we adjusted the original survey weights according to the country's population of children 12-23 months of age. To contextualize our findings, we utilized United Nations Population Division birth cohort data to estimate the study population as a proportion of the global and country income group populations.

RESULTS

We included a total of 82 countries in our univariate analyses and 68 countries in our multivariate model. Overall, 7.5% of the study population were zero dose children. More than half (51.9%) of this population was concentrated in African countries. Zero dose children were predominantly situated in rural areas (75.8%) and in households in the lowest two wealth quintiles (62.7%) and were born to mothers who completed fewer than four antenatal care (ANC) visits (66.5%) and had home births (58.5%). Yet, surprisingly, a considerable proportion of zero dose children's mothers did receive appropriate care during pregnancy (33.5% of zero dose children have mothers who received at least 4 ANC visits). When controlled for other factors, children had three times the odds (OR = 3.00, 95% CI: 2.72, 3.30) of being zero dose if their mother had not received any tetanus injections, 2.46 times the odds (95% CI: 2.21, 2.74) of being zero dose if their mother had not received any ANC visits, and had nearly twice the odds (OR = 1.87, 95% CI: 1.70, 2.05) of being zero dose if their mother had a home delivery, compared to children of mothers who received at least 2 tetanus injections, received at least 4 ANC visits, and had a facility delivery, respectively.

DISCUSSION

A lack of access to maternal health care was a strong risk factor of zero dose status and highlights important opportunities to improve the quality and integration of maternal and child health programs. Additionally, because a substantial proportion of zero dose children and their mothers do receive appropriate care, approaches to reach zero dose children should incorporate mitigating missed opportunities for vaccination.

Mapping of Pro-Equity Interventions Proposed by Immunisation Programs in Gavi Health Systems Strengthening Grants

Reaching zero-dose (ZD) children, operationally defined as children who have not received a first dose of the diphtheria, tetanus, and pertussis (DTP1) vaccine, is crucial to increase equitable immunisation coverage and access to primary health care. However, little is known about the approaches already taken by countries to improve immunisation equity. We reviewed all Health System Strengthening (HSS) proposals submitted by Gavi-supported countries from 2014 to 2021 inclusively and extracted information on interventions favouring equity. Pro-equity interventions were mapped to an analytical framework representing Gavi 5.0 programmatic guidance on reaching ZD children and missed communities. Data from keyword searches and manual screening were extracted into an Excel database. Open format responses were analysed using inductive and deductive thematic coding. Data analysis was conducted using Excel and R. Of the 56 proposals included, 51 (91%) included at least one pro-equity intervention. The most common interventions were conducting outreach sessions, tailoring the location of service delivery, and partnerships. Many proposals had "bundles" of interventions, most often involving outreach, microplanning and community-level education activities. Nearly half prioritised remote-rural areas and only 30% addressed gender-related barriers to immunisation. The findings can help identify specific interventions on which to focus future evidence syntheses, case studies and implementation research and inform discussions on what may or may not need to change to better reach ZD children and missed communities moving forward.

Individual- and Neighborhood-Level Factors of Measles Vaccination Coverage in Niamey, Niger: A Multilevel Analysis

Vaccination is a proven equitable intervention if people take advantage of the opportunity to get vaccinated. Niger is a low-income country in West Africa, with a 76% measles 1 vaccination coverage rate in 2016. This study was conducted to identify individual- and neighborhood-level factors that could improve measles 1 vaccination coverage in Niamey, the capital. In October 2016, 460 mothers with children aged 12-23 months were surveyed. The outcome was to determine whether the mother's child had been vaccinated against measles 1 or not. For individual-level variables of measles 1 vaccination status, the following were included: mother's age group, mother tongue, maternal education level, husband's job, where the mother gave birth (at home or at a health center) and whether the mother discussed vaccination with friends. Neighborhood-level factors were access time to the health center, household access to electricity, and a grand-mean-centered wealth score. Multilevel logistic regression analysis was performed. At the individual-level, primary and secondary-educated mothers were more likely to vaccinate their children against measles 1 (aOR 1.97, 95% CI 1.11-3.51). At the neighborhood-level, no factors were identified. Therefore, a strengthened focus on equity-based, individual factors is recommended, including individual motivation, prompts and ability to access vaccination services.

Vaccine equity in low and middle income countries: a systematic review and meta-analysis

BACKGROUND

Evidence to date has shown that inequality in health, and vaccination coverage in particular, can have ramifications to wider society. However, whilst individual studies have sought to characterise these heterogeneities in immunisation coverage at national level, few have taken a broad and quantitative view of the contributing factors to heterogeneity in immunisation coverage and impact, i.e. the number of cases, deaths, and disability-adjusted life years averted. This systematic review aims to highlight these geographic, demographic, and sociodemographic characteristics through a qualitative and quantitative approach, vital to prioritise and optimise vaccination policies.

METHODS

A systematic review of two databases (PubMed and Web of Science) was undertaken using search terms and keywords to identify studies examining factors on immunisation inequality and heterogeneity in vaccination coverage. Inclusion criteria were applied independently by two researchers. Studies including data on key characteristics of interest were further analysed through a meta-analysis to produce a pooled estimate of the risk ratio using a random effects model for that characteristic.

RESULTS

One hundred and eight studies were included in this review. We found that inequalities in wealth, education, and geographic access can affect vaccine impact and vaccination dropout. We estimated those living in rural areas were not significantly different in terms of full vaccination status compared to urban areas but noted considerable heterogeneity between countries. We found that females were 3% (95%CI[1%, 5%]) less likely to be fully vaccinated than males. Additionally, we estimated that children whose mothers had no formal education were 28% (95%CI[18%,47%]) less likely to be fully vaccinated than those whose mother had primary level, or above, education. Finally, we found that individuals in the poorest wealth quintile were 27% (95%CI [16%,37%]) less likely to be fully vaccinated than those in the richest.

CONCLUSIONS

We found a nuanced picture of inequality in vaccination coverage and access with wealth disparity dominating, and likely driving, other disparities. This review highlights the complex landscape of inequity and further need to design vaccination strategies targeting missed subgroups to improve and recover vaccination coverage following the COVID-19 pandemic.

TRIAL REGISTRATION

Prospero, CRD42021261927.

Vaccination dropout rates among children aged 12-23 months in Democratic Republic of the Congo: a cross-sectional study

Background

Overall, 1.8 million children fail to receive the 3-dose series for diphtheria, tetanus and pertussis each year in the Democratic Republic of the Congo (DRC). Currently, an emergency plan targeting 9 provinces including Kinshasa, the capital of the DRC, is launched to reinforce routine immunization. Mont Ngafula II was the only health district that experienced high vaccination dropout rates for nearly five consecutive years. This study aimed to identify factors predicting high immunization dropout rates among children aged 12-23 months in the Mont Ngafula II health district.

Methods

A cross-sectional household survey was conducted among 418 children in June-July 2019 using a two-stage sampling design. Socio-demographic and perception data were collected through a structured interviewer-administered questionnaire. The distribution of 2017-2018 immunization coverage and dropout rate was extracted from the local health district authority and mapped. Logistic random effects regression models were used to identify predictors of high vaccination dropout rates.

Results

Of the 14 health areas in the Mont Ngafula II health district, four reported high vaccine coverage, only one recorded low vaccine coverage, and three reported both low vaccine coverage and high dropout rate. In the final multivariate logistic random effects regression model, the predictors of immunization dropout among children aged 12-23 months were: living in rural areas, unavailability of seats, non-compliance with the order of arrival during vaccination in health facilities, and lack of a reminder system on days before the scheduled vaccination.

Conclusions

Our results advocate for prioritizing targeted interventions and programs to strengthen interpersonal communication between immunization service providers and users during vaccination in health facilities and to implement an SMS reminder system on days before the scheduled vaccination.

Factors affecting recommended childhood vaccine demand

Reaching a high vaccination coverage level is of vital essence when preventing epidemic diseases. For mandatory vaccines, the demand can be forecasted using some demographics such as birth rates or populations between certain ages. However, it has been difficult to forecast non-mandatory vaccine demands because of vaccine hesitation, alongside other factors such as social norms, literacy rate, or healthcare infrastructure. Consequently, the purpose of this study is to explore the predominant factors that affect the non-mandatory vaccine demand, focusing on the recommended childhood vaccines, which are usually excluded from national immunization programs. For this study, fifty-nine factors were determined and categorized as system-oriented and human-oriented factors. After a focus group study conducted with ten experts, seven system-oriented and eight human-oriented factors were determined. To reveal the cause and effect relationship between factors, one of the multi-criteria decision-making methods called Fuzzy-DEMATEL was implemented. The results of the analysis showed that “Immunization-related beliefs”, “Media/social media contents/messaging”, and “Social, cultural, religious norms” have a strong influence on non-mandatory childhood vaccine demand. Furthermore, whereas “Availability and access to health care facilities” and “Political/ financial support to health systems” are identified as cause group factors, “Quality of vaccine and service delivery management” is considered an effect group factor. Lastly, a guide was generated for decision-makers to help their forecasting process of non-mandatory vaccine demands to avoid vaccine waste or shortage.

Impact of campaign-style delivery of routine vaccines: a quasi-experimental evaluation using routine health services data in India

The world is not on track to achieve the goals for immunization coverage and equity described by the World Health Organization's Global Vaccine Action Plan. Many countries struggle to increase coverage of routine vaccination, and there is little evidence about how to do so effectively. In India in 2016, only 62% of children had received a full course of basic vaccines. In response, in 2017-18 the government implemented Intensified Mission Indradhanush (IMI), a nationwide effort to improve coverage and equity using a campaign-style strategy. Campaign-style approaches to routine vaccine delivery like IMI, sometimes called 'periodic intensification of routine immunization' (PIRI), are widely used, but there is little robust evidence on their effectiveness. We conducted a quasi-experimental evaluation of IMI using routine data on vaccine doses delivered, comparing districts participating and not participating in IMI. Our sample included all districts that could be merged with India's 2016 Demographic and Health Surveys data and had available data for the full study period. We used controlled interrupted time-series analysis to estimate the impact of IMI during the 4-month implementation period and in subsequent months. This method assumes that, if IMI had not occurred, vaccination trends would have changed in the same way in the participating and not participating districts. We found that, during implementation, IMI increased delivery of 13 infant vaccines, with a median effect of 10.6% (95% confidence interval 5.1% to 16.5%). We did not find evidence of a sustained effect during the 8 months after implementation ended. Over the 12 months from the beginning of implementation, we estimated reductions in the number of under-immunized children that were large but not statistically significant, ranging from 3.9% (-6.9% to 13.7%) to 35.7% (-7.5% to 77.4%) for different vaccines. The largest effects were for the first doses of vaccines against diphtheria-tetanus-pertussis and polio: IMI reached approximately one-third of children who would otherwise not have received these vaccines. This suggests that PIRI can be successful in increasing routine immunization coverage, particularly for early infant vaccines, but other approaches may be needed for sustained coverage improvements.

Determining Significant Factors Affecting Vaccine Demand and Factor Relationships Using Fuzzy DEMATEL Method

Even though deadly effects of outbreaks such as SARS, H1N1, EBOLA and COVID-19 took the attention of the community, generating 100% vaccination uptake from people who are expected to be affected by such outbreaks is almost impossible. Hence, determining the actual vaccine demand for typical viruses and reaching this population are becoming important issues to prevent from spreading such viruses like wildfire. Many countries have been forecasting vaccine demand according to birth rates. However, factors such as district-level per capita income, literacy rate, urbanization, and some other factors should also be considered for more accurate forecasts. There is another factor affecting countries’ vaccine demand; some of the vaccines that WHO recommends are included in the national immunization programs, while others are only recommended. Thus, this study first aims to explore the most significant factors that affect the demand of vaccines that are not included in national immunization campaigns then to present the cause and effect relationships among the factors using the fuzzy DEMATEL method to provide insights to managers for better vaccine demand forecast and to increase vaccine uptake. According to the analysis results, immunization related beliefs is the most important factor among others included in this research.

Impact of Multiple Risk Factors on Vaccination Inequities: Analysis in Indian Infants Over 2 Decades

INTRODUCTION

Several authors have explored the effect of individual risk factors on vaccination inequity in Indian infants. This study explores the combined impact of >1 risk factor on the probability of full vaccination.

METHODS

The proportion of fully vaccinated infants (aged 1-2 years) was calculated from the National Family Health Survey conducted during 1997-1998 (National Family Health Survey-2, n=10,211), 2005-2006 (National Family Health Survey-3, n=9,582), and 2015-2016 (National Family Health Survey-4, n=48,715). Full vaccination was defined as receiving Bacille Calmette‒Guerin (1 dose); diphtheria, pertussis, tetanus (3 doses); oral polio (3 doses); and measles (1 dose) vaccines. The association between full vaccination status and 6 factors (infant sex, birth order, family wealth status, maternal education level, residence type, and religion) was analyzed individually, followed by the combined impact of ≥1 of the first 4, using logistic regression models.

RESULTS

The AORs for full vaccination in the 3 surveys, respectively, were 1.09, 1.13, and 1.00 for male versus female infants; 0.68, 0.71, and 0.88 for birth order >1 versus birth order 1; 1.54, 1.96, and 1.20 for greater wealth versus lowest wealth stratum; 2.21, 2.27, and 1.27 for any maternal education versus none; 1.08, 1.10, and 1.08 for Hindu versus other religion; and 1.51, 1.10, and 0.88 for urban versus rural residence. The respective ORs of full vaccination in the 3 surveys by the number of risk factors were as follows: 1.26, 1.54, and 1.27 for 3 risk factors; 2.41, 3.23, and 1.68 for 2 risk factors; 4.42, 6.45, and 2.18 for 1 risk factor; and 7.32, 9.84, and 2.61 for no risk factor.

CONCLUSIONS

The presence of multiple risk factors had a cumulative negative impact on infant vaccination in India. Despite an improvement over 2 decades, significant inequities persist.

SUPPLEMENT INFORMATION

This article is part of a supplement entitled Global Vaccination Equity, which is sponsored by the Global Institute for Vaccine Equity at the University of Michigan School of Public Health.

Inequities in child survival in Nigerian communities during the Sustainable Development Goal era: insights from analysis of 2016/2017 Multiple Indicator Cluster Survey

BACKGROUND

Child survival is a major concern in Nigeria, as it contributes 13% of the global under-five mortalities. Although studies have examined the determinants of under-five mortality in Nigeria, the comparative roles of social determinants of health at the different stages of early childhood development have not been concurrently investigated. This study, therefore, aimed to identify the social determinants of age-specific childhood (0-59 months) mortalities, which are disaggregated into neonatal mortality (0-27 days), post-neonatal mortality (1-11 months) and child mortality (12-59 months), and estimate the within-and between-community variations of mortality among under-five children in Nigeria. This study provides evidence to guide stakeholders in planning for effective child survival strategies in the Nigerian communities during the Sustainable Development Goals era.

METHODS

Using the 2016/2017 Nigeria Multiple Indicator Cluster Survey, we performed multilevel multinomial logistic regression analysis on data of a nationally representative sample of 29,786 (weighted = 30,960) live births delivered 5 years before the survey to 18,497 women aged 15-49 years and nested within 16,151 households and 2227 communities.

RESULTS

Determinants of under-five mortality differ across the neonatal, post-neonatal and toddler/pre-school stages in Nigeria. Unexpectedly, attendance of skilled health providers during delivery was associated with an increased neonatal mortality risk, although its effect disappeared during post-neonatal and toddler/pre-school stages. Also, our study found maternal-level factors such as maternal education, contraceptive use, maternal wealth index, parity, death of previous children, and quality of perinatal care accounted for high variation (39%) in childhood mortalities across the communities. The inclusion of other compositional and contextual factors had no significant additional effect on childhood mortality risks across the communities.

CONCLUSION

This study reinforces the importance of maternal-level factors in reducing childhood mortality, independent of the child, household, and community-level characteristics in the Nigerian communities. To tackle childhood mortalities in the communities, government-led strategies should prioritize implementation of community-based and community-specific interventions aimed at improving socioeconomic conditions of women. Training and continuous mentoring with adequate supervision of skilled health workers must be ensured to improve the quality of perinatal care in Nigeria.

Compositional and contextual factors associated with drug overdose deaths in the United States

Background: In 2017, the US Department of Health and Human Services declared the Opioid epidemic a public health emergency. In the US, emergency rooms treat more than 1,000 people each day for drug overdose, and 115 of them die. This study examines compositional and contextual factors associated with drug overdose deaths rates in the US. Methods: Local spatial autocorrelation statistics were used to estimate hot spot areas to identify census tracts with high risk of drug overdose death. Logistic regressions investigated the relationship between drug overdose death rates and various compositional and contextual variables across census tracks. Results: The adjusted logistic model shows that compositional variables: depression (OR = 2.47 [2.37-2.58]), poor mental health (OR = 1.71 [1.63-1.79]), median age 1.41 (1.36-1.47) and the percentage of people with a high school diploma (OR = 1.30 [1.24-1.35]) were positively associated with the rate of drug overdose deaths. On the other hand, contextual variables: the percentage having health insurance (OR = 0.66 [0.64-0.69]), the Theil's H index (OR = 0.69 [0.66-0.71]), population density (OR = 0.80 [0.77-0.84]), poverty (OR = 0.90 [0.86-0.95]), and median household income (OR = 0.91[0.86-0.96]) were negatively associated with drug overdose deaths. Discussion: The analysis reveals a consistently strong association between compositional mental health factors and census tract-level death rates from drug overdose.

Decomposing socioeconomic inequality in child vaccination in the Gambia, the Kyrgyz Republic and Namibia

Extant work suggested pro-rich distribution of vaccination coverage in low- and middle-income countries (LMICs). However, the current literature also suggested pro-poor distribution of vaccination in some countries, including the Gambia, the Kyrgyz Republic and Namibia. This study aimed to explain socioeconomic inequalities in the completion rate of the four-core vaccines (i.e., Bacille Calmette-Guérin [BCG], diphtheria-tetanus-pertussis [DTP, 3 doses], Polio [3 doses] and Measles vaccines) in the three aforementioned countries. We used the most recent available Demographic Health Surveys (DHS) to measure vaccination completion rates among children (aged 0-59 months, n = 16,752) in the three countries. The normalized concentration index (C_n) was used to quantify and decompose socioeconomic inequalities in vaccination coverage in each country. The negative values of the C_n index suggested that children belong to lower socioeconomic status groups were more likely to be immunized than their higher socioeconomic status counterparts in the Gambia (C_n = -0.101, 95% confidence interval [CI]: -0.128 to -0.074), the Kyrgyz Republic (C_n = -0.097, 95% CI: -0.13 to -0.063) and Namibia (C_n = -0.161, 95% CI: -0.199 to -0.124). The decomposition analysis of the C_n suggested that the difference in child vaccination completion rates between rural and urban areas was the main factor contributing to the concentration of child vaccination among the poor in the Gambia and Namibia. The concentration of child vaccination among the poor in the Kyrgyz Republic was chiefly determined by household wealth. These results suggest that there should be strategies to improve child immunization uptake among urban children in the Gambia and Namibia. Since household wealth was the main factor contributing to the observed pro-poor distribution of child vaccination in the Kyrgyz Republic, further studies are required to understand the reasons for lower vaccination rate among the wealthy children in order to implement the most effective strategies to increase child vaccination uptake.

Understanding Spatial and Contextual Factors Influencing Intraregional Differences in Child Vaccination Coverage in Bangladesh

In Bangladesh, policy discourse has mostly focused on regional inequities in health, including child immunization coverage. Knowledge of local geographical and contextual factors within regions, however, becomes pertinent in efforts to address these inequities. We used the Bangladesh Demographic and Health Survey 2011 to examine factors that influence intraregional differences in vaccination coverage using a multilevel analysis. We found that in spite of the provision of health facilities at each level of administrative governance, only distance to the Upazilla Health Complex was a consistent predictor for each dose of vaccine, highlighting the remote locations of the communities that remain underserved. Our analysis demonstrates the value of subregional analyses that identify the characteristics of communities that are vulnerable to incomplete immunization coverage. Unless specific policy actions are taken to increase coverage in these remote areas, geographic inequities are likely to persist within regions, and desired targets will not be achieved.

What is causing high polio vaccine dropout among Pakistani children?

OBJECTIVES

Although the antipolio drive is undertaken across Pakistan, there are still children who have not received any oral polio vaccine or are unable to complete recommended doses of polio vaccine. This study aims at empirically analyzing the associated factors with the no oral polio vaccination (OPV) and OPV dropout groups of children in Pakistan.

STUDY DESIGN

This is a cross-sectional study.

METHODS

Data were obtained from the three waves of Pakistan Demographic and Health Survey of children aged between 12 and 23 months (1990-1991: n = 1214; 2006-2007: n = 1522; 2012-2013: n = 2074). Children who received no OPV and those who drop out of polio vaccination (OPV1-OPV3) were considered as outcome variables. The bivariate relationship of outcome variable with each socio-economic, demographic, and spatial variable is estimated with a P-value of <0.01. For both no OPV and OPV dropout children, we used logistic regression analysis separately.

RESULTS

The percentage of children aged 12-23 months who dropped out of OPV1-OPV3 vaccination was about 76% in the year 1990-1991; 21% in 2006-2007, and 17.5% in 2012-2013 at the national level. Among all indicators, provinces, rural versus urban residence, the mother's age at marriage, the child's birth place (home versus hospital), parental education, and household wealth status are significant predictors of no OPV and/or OPV dropout in Pakistan. Among provinces, Balochistan, Khyber Pakhtunkhwa (KPK), and Sindh are the lagging provinces.

CONCLUSION

Improving the socio-economic status of women helps decrease the chance of polio dropout and thus improves service delivery and program implementation.

Demand-side determinants of timely vaccination of oral polio vaccine in social mobilization network areas of CORE Group polio project in Uttar Pradesh, India

Background

Children who receive all doses of scheduled vaccines reduce their susceptibility to vaccine-preventable diseases. In India, full immunization coverage has increased significantly. However, only a small proportion of children are immunized on time. Globally, studies on factors affecting coverage of childhood immunization have found a significant impact by demand and supply-side determinants. This paper explores the demand-side determinants of timely immunization of the third dose of oral polio vaccine (OPV3) among children aged 6–11 months in the catchment areas of CORE Group Polio Project India.

Methods

We analyzed secondary de-identified data from a household level ‘Doers and Non-doers survey’ conducted in 2015. Determinants of timely OPV3 immunization were identified by modeling the characteristics of index children and survey respondents, surveyed households, respondents’ media habits, their exposure to immunization services and perceptions towards child immunization, through a multinomial regression analysis.

Results

The eight demand-side predictors based on the background characteristics and perceptions of caregivers determined timely vaccination of OPV3. The strongest predictor of timely OPV3 immunization was found to be the fathers’ educational level. Children of uneducated or lesser educated fathers had increased odds of not receiving the OPV1 vaccination, as compared to children of more educated fathers (OR > 10). Respondents who strongly perceived other (non-health) benefits of child immunization were three times more likely to timely vaccinate their children than those who do not. Furthermore, mothers who disagreed with the positive attributes of child immunization were 25 times more likely to delay or not to take their children for OPV immunization on time.

Conclusions

This study found eight essential factors that are responsible for timely OPV3. Despite limitations in data collection and analysis, immunization programs in India could use the eight identified demand-side determinants of timeliness and tailor communication strategies accordingly. We suggest that program communication efforts be directed at male community members; such messaging should address parents’ perceptions of non-health benefits and stress the positive attributes of child immunization. Further investigation would be helpful to assess the various risk factors of under-vaccination as well as vaccinators’ understating about timely immunization.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3129-2) contains supplementary material, which is available to authorized users.

Factors associated with routine childhood vaccine uptake and reasons for non-vaccination in India: 1998-2008

BACKGROUND

Despite almost three decades of the Universal Immunization Program in India, a little more than half the children aged 12-23months receive the full schedule of routine vaccinations. We examined socio-demographic factors associated with partial-vaccination and non-vaccination and the reasons for non-vaccination among Indian children during 1998 and 2008.

METHODS

Data from three consecutive, nationally-representative, District Level Household and Facility Surveys (1998-99, 2002-04 and 2007-08) were pooled. Multinomial logistic regression was used to identify individual and household level socio-demographic variables associated with the child's vaccination status. The mother's reported reasons for non-vaccination were analyzed qualitatively, adapting from a previously published framework.

RESULTS

The pooled dataset contained information on 178,473 children 12-23months of age; 53%, 32% and 15% were fully vaccinated, partially vaccinated and unvaccinated respectively. Compared with the 1998-1999 survey, children in the 2007-2008 survey were less likely to be unvaccinated (Adjusted Prevalence Odds Ratio (aPOR): 0.92, 95%CI=0.86-0.98) but more likely to be partially vaccinated (aPOR: 1.58, 95%CI=1.52-1.65). Vaccination status was inversely associated with female gender, Muslim religion, lower caste, urban residence and maternal characteristics such as lower educational attainment, non-institutional delivery, fewer antenatal care visits and non-receipt of maternal tetanus vaccination. The mother's reported reasons for non-vaccination indicated gaps in awareness, acceptance and affordability (financial and non-financial costs) related to routine vaccinations.

CONCLUSIONS

Persisting socio-demographic disparities related to partial-vaccination and non-vaccination were associated with important childhood, maternal and household characteristics. Further research investigating the causal pathways through which maternal and social characteristics influence decision-making for childhood vaccinations is needed to improve uptake of routine vaccination in India. Also, efforts to increase uptake should address parental fears related to vaccination to improve trust in government health services as part of ongoing social mobilization and communication strategies.

Demand- and supply-side determinants of diphtheria-pertussis-tetanus nonvaccination and dropout in rural India

BACKGROUND

Although 93% of 12- to 23-month-old children in India receive at least one vaccine, typically Bacillus Calmette-Guérin, only 75% complete the recommended three doses of diphtheria-pertussis-tetanus (DPT, also referred to as DTP) vaccine. Determinants can be different for nonvaccination and dropout but have not been examined in earlier studies. We use the three-dose DPT series as a proxy for the full sequence of recommended childhood vaccines and examine the determinants of DPT nonvaccination and dropout between doses 1 and 3.

METHODS

We analyzed data on 75,728 6- to 23-month-old children in villages across India to study demand- and supply-side factors determining nonvaccination with DPT and dropout between DPT doses 1 and 3, using a multilevel approach. Data come from the District Level Household and Facility Survey 3 (2007-08).

RESULTS

Individual- and household-level factors were associated with both DPT nonvaccination and dropout between doses 1 and 3. Children whose mothers had no schooling were 2.3 times more likely not to receive any DPT vaccination and 1.5 times more likely to drop out between DPT doses 1 and 3, compared with children whose mothers had 10 or more years of schooling. Although supply-side factors related to availability of public health facilities and immunization-related health workers in villages were not correlated with dropout between DPT doses 1 and 3, children in districts where 46% or more villages had a healthcare subcentre were 1.5 times more likely to receive at least one dose of DPT vaccine compared with children in districts where 30% or fewer villages had subcentres.

CONCLUSIONS

Nonvaccination with DPT in India is influenced by village- and district-level contextual factors over and above individuals' background characteristics. Dropout between DPT doses 1 and 3 is associated more strongly with demand-side factors than with village- and district-level supply-side factors.