Is vaccination coverage a good indicator of age-appropriate vaccination? A prospective study from Uganda

SMS-based interventions for improving child and adolescent vaccine coverage and timeliness: a systematic review

BACKGROUND

The aim of this review was to investigate the impact of short message service (SMS)-based interventions on childhood and adolescent vaccine coverage and timeliness.

METHODS

A pre-defined search strategy was used to identify all relevant publications up until July 2022 from electronic databases. Reports of randomised trials written in English and involving children and adolescents less than 18 years old were included. The review was conducted in accordance with PRISMA guidelines.

RESULTS

Thirty randomised trials were identified. Most trials were conducted in high-income countries. There was marked heterogeneity between studies. SMS-based interventions were associated with small to moderate improvements in vaccine coverage and timeliness compared to no SMS reminder. Reminders with embedded education or which were combined with monetary incentives performed better than simple reminders in some settings.

CONCLUSION

Some SMS-based interventions appear effective for improving child vaccine coverage and timeliness in some settings. Future studies should focus on identifying which features of SMS-based strategies, including the message content and timing, are determinants of effectiveness.

Predictors of timeliness of vaccination among children of age 12-23 months in Boricha district, Sidama region Ethiopia, in 2019

BACKGROUND

Traditional measurement of vaccine coverage can mask the magnitude of timely uptake of vaccine. Hence, the optimal measurement of timeliness is unclear due to variations in vaccine schedule among countries in the world. In Ethiopia, Oral Polio Virus (OPV), Pentavalent, Tetanus, H. influenza type B, Hepatitis B, and Pneumonia-Conjugate Vaccine (PCV) are basic vaccines which are taken at birth, six weeks, ten weeks, and fourteen weeks respectively. Despite its importance, information is scarce about on-time vaccination in the study area. Therefore, this study aimed to assess prevalence and factors associated with on-time vaccination among children of age 12-23 months in Boricha district, Sidama Ethiopia, in 2019.

METHODS

A community based survey was conducted in Boricha district, Sidama region Ethiopia from January 1-30 in 2019. Study participants were selected using stratified multistage sampling technique. Kebeles were stratified based on residence. First, Kebeles were selected using random sampling. Then, systematic random sampling was employed to reach each household. Data were collected using structured and interviewer administered questionnaire. Logistic regression analysis was employed to identify factors associated with timely vaccination. Then, independent variables with p-value < 0.25 in COR were fitted further into multivariate logistic regression analysis model to control the possible cofounders. AOR with 95% CI and p-value < 0.05 was computed and reported as the level of statistical significance.

RESULTS

From a total of 614 study participants, only 609 study participants have responded to questions completely making a response rate of 99.2%. Prevalence of timeliness of vaccination was 26.8% (95% CI: 25, 28) in this study. Factors like children of women with formal education (AOR = 5.3, 95%CI,2.7, 10.4), absence of antenatal care visit (AOR = 4.2,95%CI, 1.8,9.8), home delivery (AOR = 6.2,95%CI,4.0,9.3), lack of postnatal care (AOR = 3.7,95%CI,1.1,13.3), and lack of information about when vaccines completion date (AOR = 2.0, 95% CI,1.13,3.8) were factors influences timely vaccination among children of age 12-23 months.

CONCLUSION

Prevalence of on-time vaccination among children of age 12-23 months is lower than national threshold. Therefore, sustained health education on vaccination schedule and reminder strategies should be designed and implemented. Furthermore, maternal and child health care services should be enhanced and coordinated to improve on-time uptake of vaccine.

High coverage and timeliness of vaccination of children under 6 years of age in Risaralda, Colombia

This study determined the coverage and timeliness of immunization in children <6 y from Risaralda, Colombia. A retrospective cross-sectional study evaluated data from a vaccination coverage and timeliness verification survey conducted in 2019, including 2457 children <6 y from Risaralda, Colombia. Variables included demographics, a record of vaccinations included in the Colombian Vaccination Plan, and date of immunization. Vaccination was defined as timely until 29 d after the day established by the plan. Coverage was over 95% for all vaccinations, except the boosters of diphtheria/pertussis/tetanus (DTP) and oral polio at 18 months (91.0%), influenza (85.6%), and yellow fever (49.2%). Most surveyed children demonstrated very high timeliness of vaccination, with values close to, or over, 90%, although there were exceptions for pentavalent (DTP+Haemophilus influenzae type B+hepatitis B) and polio vaccines at 6 months (79.4%), influenza (85.6%), and yellow fever (49.2%). Before the COVID-19 pandemic, Colombian Vaccination Plan demonstrated high coverage and timeliness of vaccination of children <6 y of age; however, timeliness for the third dose of DTP-Hib-HBV and polio showed opportunities for improvement.

Beyond coverage: Rural-urban disparities in the timeliness of childhood vaccinations in Tanzania

BACKGROUND

Timely vaccination maximizes efficacy for preventing infectious diseases. In the absence of national vaccination registries, representative sample survey data hold vital information on vaccination coverage and timeliness. This study characterizes vaccination coverage and timeliness in Tanzania and provides an analytic template to inform contextually relevant interventions and evaluate immunization programs.

METHODS

Cross-sectional data on 6,092 children under age 3 from the 2015-16 Tanzania Demographic and Health Survey were used to examine coverage and timeliness for 14 vaccine doses recommended in the first year of life. The Kaplan-Meier method was used to model time to vaccination. Cox proportional hazard models were used to examine factors associated with timely vaccination.

RESULTS

Substantial rural-urban disparities in vaccination coverage and timeliness were observed for all vaccines. Across 14 recommended doses, documented coverage ranged from 52 % to 79 %. Median vaccination delays lasted up to 35 days; gaps were larger among rural than urban children and for later doses in vaccine series. Among rural children, median delays exceeded 35 days for the 3rd doses of the polio, pentavalent, and pneumococcal vaccines. Median delays among urban children were < 21 days for all doses. Among rural and urban children, lower maternal education and delivery at home were associated with increased risk of delayed vaccination. In rural settings, less household wealth and greater distance to a health facility were also associated with increased risk of delayed vaccination.

DISCUSSION

This study highlights persistent gaps in uptake and timeliness of childhood vaccinations in Tanzania and substantial rural-urban disparities. While the results provide an informative situation assessment and outline strategies for identifying unvaccinated children, a national electronic registry is critical for comprehensive assessments of the performance of vaccination programs. The timeliness measure employed in this study-the amount of time children are un- or undervaccinated-may serve as a sensitive performance metric for these programs.

Coverage and Drivers to Reaching the Last Child With Vaccination in Urban Settings: A Mixed-Methods Study in Kampala, Uganda

BACKGROUND

Limited evidence exists regarding the drivers of vaccination coverage and equity in Kampala city, despite frequent measles outbreaks, inequities in vaccination coverage, and the decline in vaccination coverage rates. This study was designed to determine vaccine coverage among children aged 12-36 months and to understand its demand-side drivers.

METHODS

We utilized a mixed-methods parallel convergent study design. A household survey was conducted to quantify the drivers of vaccine coverage among households with children aged 12-36 months. We employed a multistage sampling approach to select households, using a primary sampling unit of an enumeration area. We conducted 30 key informant interviews, 7 focus group discussions, and 6 in-depth interviews with representatives from the immunization program, health workers, and parents residing in areas with low vaccine coverage.

RESULTS

Of the 590 enrolled children, 340 (57.6%) were partially vaccinated, 244 (41.4%) were fully vaccinated and had received all the recommended vaccinations, and 6 (1.0%) had never received any vaccine. Of the 244 with all recommended vaccinations, only 65 (26.6%) received their vaccines on time. Access to vaccination services was high (first dose of diphtheria, pertussis, and tetanus [DPT1] coverage of 96%), but utilization decreased over time, as shown by a dropout rate of 17.3% from the first to third dose of DPT. The main driver of complete vaccination was the parents' appreciation of the benefits of vaccination. Among partially vaccinated children, the barriers to vaccination were inadequate information about vaccination (its benefits and schedule), vaccine stock-outs, long waiting times to receive vaccination services, and hidden vaccination costs.

CONCLUSION

Vaccination needs to be targeted to all children irrespective of whether they reside in slum areas or nonslum areas, as most are under-vaccinated. Social mobilization and communication efforts should be tailored to the complexities of urban settings characterized by transient and diverse populations with different cultures.

Timeliness of routine childhood vaccination in 103 low-and middle-income countries, 1978-2021: A scoping review to map measurement and methodological gaps

Empiric studies exploring the timeliness of routine vaccination in low-and middle-income countries (LMICs) have gained momentum in the last decade. Nevertheless, there is emerging evidence suggesting that these studies have key measurement and methodological gaps that limit their comparability and utility. Hence, there is a need to identify, and document these gaps which could inform the design, conduct, and reporting of future research on the timeliness of vaccination. We synthesised the literature to determine the methodological and measurement gaps in the assessment of vaccination timeliness in LMICs. We searched five electronic databases for peer-reviewed articles in English and French that evaluated vaccination timeliness in LMICs, and were published between 01 January 1978, and 01 July 2021. Two reviewers independently screened titles and abstracts and reviewed full texts of relevant articles, following the guidance framework for scoping reviews by the Joanna Briggs Institute. From the 4263 titles identified, we included 224 articles from 103 countries. China (40), India (27), and Kenya (23) had the highest number of publications respectively. Of the three domains of timeliness, the most studied domain was 'delayed vaccination' [99.5% (223/224)], followed by 'early vaccination' [21.9% (49/224)], and 'untimely interval vaccination' [9% (20/224)]. Definitions for early (seven different definitions), untimely interval (four different definitions), and delayed vaccination (19 different definitions) varied across the studies. Most studies [72.3% (166/224)] operationalised vaccination timeliness as a categorical variable, compared to only 9.8% (22/224) of studies that operationalised timeliness as continuous variables. A large proportion of studies [47.8% (107/224)] excluded the data of children with no written vaccination records irrespective of caregivers' recall of their vaccination status. Our findings show that studies on vaccination timeliness in LMICs has measurement and methodological gaps. We recommend the development and implement of guidelines for measuring and reporting vaccination timeliness to bridge these gaps.

Timely completion of childhood vaccination and its predictors in Burkina Faso

BACKGROUND

Despite important progress in global vaccination coverage, many countries are still facing preventable disease outbreaks. Timely vaccination is important in getting adequate protection against disease. In light of the paucity of relevant literature, this study investigated the timely completion of childhood routine immunization and identified factors associated with timely vaccination in Burkina Faso.

METHODS

We extracted data on child vaccination and other child characteristics from a household survey conducted across 24 districts in 2017. We extracted data on health system characteristics from a parallel facility survey. We applied a Kaplan-Meier time-to-event analysis to estimate timely vaccination coverage defined as the proportion of children that received a given vaccine in the period between three days before and 28 days after the recommended age. We used a Cox proportional hazard model with mixed effects to identify factors associated with timely vaccination.

RESULTS

In total, 3,138 children aged between 16 and 36 months who could present an immunization booklet were included in the study.The main finding is the existence of an important gap showing that timely vaccination coverage was lower than vaccination coverage. More specifically,this gap ranged from 16% for BCG to 43% for Penta 3. In addition, region and distance between the household and the nearest health facility were the main factors associated with timely full vaccination coverage and specifically for Penta3, MCV1 and MCV2.

CONCLUSIONS

This study highlights that timely vaccination coverage remains substantially lower than vaccination coverage. Timeliness of vaccination should therefore be considered as a metric to assess the status of immunization in a country. Geographical accessibility continues to represent a major barrier to timely vaccination, calling for specific interventions on both supply-side (e.g. outreach activities) and demand-side (e.g. vouchers or community-based interventions for vaccination) to counteract its negative effect.

Does mothers' and caregivers' access to information on their child's vaccination card impact the timing of their child's measles vaccination in Uganda?

Introduction

On-time measles vaccination is essential for preventing measles infection among children as early in life as possible, especially in areas where measles outbreaks occur frequently. Characterizing the timing of routine measles vaccination (MCV1) among children and identifying risk factors for delayed measles vaccination is important for addressing barriers to recommended childhood vaccination and increasing on-time MCV1 coverage. We aim to assess the timing of children's MCV1 vaccination and to investigate the association between demographic and healthcare factors, mothers'/caregivers' ability to identify information on their child’s vaccination card, and achieving on-time (vs. delayed) MCV1 vaccination.

Methods

We conducted a population-based, door-to-door survey in Kampala, Uganda, from June–August of 2019. We surveyed mothers/caregivers of children aged one to five years to determine how familiar they were with their child’s vaccination card and to determine their child’s MCV1 vaccination status and timing. We assessed the proportion of children vaccinated for MCV1 on-time and delayed, and we evaluated the association between mothers'/caregivers' ability to identify key pieces of information (child’s birth date, sex, and MCV1 date) on their child’s vaccination card and achieving on-time MCV1 vaccination.

Results

Of the 999 mothers/caregivers enrolled, the median age was 27 years (17–50), and median child age was 29 months (12–72). Information on vaccination status was available for 66.0% (n = 659) of children. Of those who had documentation of MCV1 vaccination (n = 475), less than half (46.5%; n = 221) achieved on-time MCV1 vaccination and 53.5% (n = 254) were delayed. We found that only 47.9% (n = 264) of the 551 mothers/caregivers who were asked to identify key pieces of information on their child's vaccination card were able to identify the information, but ability to identify the key pieces of information on the card was not independently associated with achieving on-time MCV1 vaccination.

Conclusion

Mothers'/caregivers' ability to identify key pieces of information on their child’s vaccination card was not associated with achieving on-time MCV1 vaccination. Further research can shed light on interventions that may prompt or remind mothers/caregivers of the time and age when their child is due for measles vaccine to increase the chance of the child receiving it at the recommended time.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-13113-z.

Effect of Mobile Phone Text Message Reminders on the Completion and Timely Receipt of Routine Childhood Vaccinations: Superiority Randomized Controlled Trial in Northwest Ethiopia

BACKGROUND

Nonattendance at vaccination appointments is a big challenge for health workers as it is difficult to track routine vaccination schedules. In Ethiopia, 3 out of 10 children have incomplete vaccination and the timely receipt of the recommended vaccines is low. Thus, innovative strategies are required to reach the last mile where mobile technology can be effectively utilized to achieve better compliance. Despite this promising technology, little is known about the role of text message-based mobile health interventions in improving the complete and timely receipt of routine childhood vaccinations in Ethiopia.

OBJECTIVE

This trial aimed to determine the effect of mobile phone text message reminders on the completion and timely receipt of routine childhood vaccinations in northwest Ethiopia.

METHODS

A two-arm, parallel, superiority randomized controlled trial was conducted in 9 health facilities in northwest Ethiopia. A sample size of 434 mother-infant pairs was considered in this trial. Randomization was applied in selected health facilities during enrollment with a 1:1 allocation ratio by using sealed and opaque envelopes. Participants assigned to the intervention group received mobile phone text message reminders one day before the scheduled vaccination visits. Owing to the nature of the intervention, blinding of participants was not possible. Primary outcomes of full and timely completion of vaccinations were measured objectively at 12 months. A two-sample test of proportion and log-binomial regression analyses were used to compare the outcomes between the study groups. A modified intention-to-treat analysis approach was applied and a one-tailed test was reported, considering the superiority design of the trial.

RESULTS

A total of 426 participants were included for the analysis. We found that a higher proportion of infants in the intervention group received Penta-3 (204/213, 95.8% vs 185/213, 86.9%, respectively; P<.001), measles (195/213, 91.5% vs 169/213, 79.3%, respectively; P<.001), and full vaccination (176/213, 82.6% vs 151/213, 70.9%, respectively; P=.002; risk ratio 1.17, 95% lower CI 1.07) compared to infants in the usual care group. Similarly, a higher proportion of infants in the intervention group received Penta-3 (181/204, 88.7% vs 128/185, 69.2%, respectively; P<.001), measles (170/195, 87.1% vs 116/169, 68.6%, respectively; P<.001), and all scheduled vaccinations (135/213, 63.3% vs 85/213, 39.9%, respectively; P<.001; risk ratio 1.59, 95% lower CI 1.35) on time compared to infants in the usual care group. Of the automatically sent 852 mobile phone text messages, 764 (89.7%) were delivered successfully to the participants.

CONCLUSIONS

Mobile phone text message reminders significantly improved complete and timely receipt of all recommended vaccines. Besides, they had a significant effect in improving the timely receipt of specific vaccines. Thus, text message reminders can be used to supplement the routine immunization program in resource-limited settings. Considering different contexts, studies on the implementation challenges of mobile health interventions are recommended.

TRIAL REGISTRATION

Pan African Clinical Trial Registry PACTR201901533237287; https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=5839.

Participation in an action research project on vaccine services for children: relationship with vaccine delays

Multicomponent interventions are effective in improving vaccine coverage. However, few studies have assessed their effect on timely vaccination. The aim of this study was to compare the proportion of children with vaccine delays at 2- and 12-month visits according to whether or not health centers have participated in an action research project on the organization of vaccination services for 0-5-year-olds. The action research project included a multicomponent intervention and was conducted between 2011 and 2015 in Quebec, Canada. An ecological before/after design was used for this analysis. A total of 264,579 DTaP-IPV-Hib (2-month visits) and 240,541 Men-C-C (12-month visits) vaccine doses were administered during 2011-2012 to 2014-2015 fiscal years, including 19% in 14 participating health centers and the remaining in 78 nonparticipating centers. Vaccine delays demonstrated a more pronounced decreasing trend in participating versus nonparticipating health centers (p < .0001 at 2 and 12 months). Between 2011-2012 and 2014-2015, participating centers managed to eliminate 35% of their vaccine delays at 2-month visits and 33% at 12-month visits, whereas nonparticipating centers eliminated 19% of delays at both visits. Our results are consistent with a positive impact of the multicomponent intervention, despite the fact that it had not specifically aimed at decreasing vaccine delays.

Timely completion of vaccination and its determinants among children in northwest, Ethiopia: a multilevel analysis

BACKGROUND

Timely vaccination is key to prevent unnecessary childhood mortality from vaccine-preventable diseases. Despite the substantial efforts to improve vaccination completeness, the effort towards timeliness of vaccination is limited with non-attendance and delays to vaccination appointments remaining a big challenge in developing countries. There is also a limited evidence on timeliness of vaccination. Therefore, this study aimed to determine the magnitude and associated factors for timely completion of vaccination among children in Gondar city administration, north-west, Ethiopia.

METHOD

This study employed a community-based cross sectional study design. A sample size of 821 children aged 12 to 23 months were considered. Two stages random sampling technique was used to select study subjects. To account the effect of clustering, bivariable and multivariable multilevel logistic regression analysis were applied. The measures of association estimates were expressed as adjusted odds ratio (AOR) with their 95% confidence intervals (CIs).

RESULTS

Of the 774 children included for analysis, 498 (64.3%) were fully vaccinated while 247 (31.9%) were fully vaccinated on-time. Caregivers who had secondary education and above (AOR = 2.391; 95% CI: 1.317-4.343), from richest households (AOR = 2.381; 95% CI: 1.502-3.773), children whose mother attended four or more ante natal care visits (AOR = 2.844; 95% CI: 1.310-6.174) and whose mother had two or more post natal care visits (AOR = 2.054; 95%CI:1.377-3.063) were positively associated with on-time full vaccination. In contrary, caregivers aged above 35 years (AOR = 0.469; 95 % CI: 0.253-0.869], being vaccinated at health post (AOR = 0.144; 95%CI: 0.048-0.428) and travelling more than 30 min to the vaccination site (AOR = 0.158; 95%CI: 0.033-0.739) were negatively associated with on-time full vaccination. The random effects indicated that 26% of the variability in on-time full vaccination was attributable to differences between communities.

CONCLUSION

In this study, untimely vaccination was found to be high. Different individual and contextual factors were found to be associated with on-time full vaccination. Therefore, tailored strategies have to be designed and implemented to address people and the communities where they live. Moreover, timeliness of vaccination should be considered as important indicator of the immunization program performance in Ethiopia.

Individual-level predictors of practices of nutrition-specific and nutrition-sensitive interventions for infants and young children in West and Central Africa: a cross-sectional study

OBJECTIVES

To explore the role of individual-level and household-level characteristics for practice of nutrition-specific and nutrition-sensitive interventions.

DESIGN

Secondary data analysis (cross-sectional).

SETTING

West and Central Africa.

PARTICIPANTS

Data are from the Demographic and Health Surveys in the time period between 1986 and 2016. The final sample included between 116 325 and 272 238 observations depending on the outcome.

PRIMARY AND SECONDARY OUTCOME MEASURES

Nutrition-specific and nutrition-sensitive interventions were identified based on the UNICEF Conceptual Framework for child undernutrition. These were early breastfeeding initiation, minimum dietary diversity, full age-appropriate immunisation, iodised salt usage, vitamin A supplementation, iron supplementation, deworming in children aged 1 to 5, clean cooking fuel, safe drinking water and improved sanitation. Explanatory variables include household, mother and child characteristics. Linear probability models were fitted for each outcome, both unadjusted as well as fully adjusted including primary sampling unit fixed effects.

RESULTS

Prevalence of early breastfeeding initiation was 54.31% (95% CI: 53.22% to 55.41%), minimum dietary diversity 13.89% (95% CI: 13.19% to 14.59%), full age-appropriate immunisation 13.04% (95% CI: 12.49% to 13.59%), iodised salt usage 49.66% (95% CI: 46.79% to 52.53%), vitamin A supplementation 52.87% (95% CI: 51.41% to 54.33%), iron supplementation 10.73% (95% CI: 10.07% to 11.39%), deworming 31.33% (95% CI: 30.06% to 32.60%), clean cooking fuel usage 3.02% (95% CI: 2.66% to 3.38%), safe drinking water 57.85% (95% CI: 56.10% to 59.59%) and improved sanitation 42.49% (95% CI: 40.77% to 44.21%). There was a positive education and wealth gradient for the practices of all interventions except deworming. Higher birth order was positively associated with the practice of early breastfeeding initiation, minimum dietary diversity, vitamin A supplementation and negatively associated with full immunisation and improved sanitation.

CONCLUSIONS

Household, maternal, and child-level characteristics explain practices of nutrition-specific and nutrition-sensitive interventions beyond intervention delivery at the regional level.

Socio-demographic Determinants of Vaccine Coverage for Pneumococcus and Rotavirus among under Five Children in Busolwe Town Council, Butaleja District, Eastern Uganda: A Cross Sectional Study

BACKGROUND AND AIMS

There is a high burden of vaccine-preventable diseases in the children under five years of age, particularly pneumonia diarrhea and which is greatly affected by low immunization coverage despite the existing efforts and policies. This study was carried out in Butaleja district and was aimed at establishing the socio-demographic determinants of vaccine coverage for pneumococcus and rotavirus among under five children (U5C) in the district.

STUDY DESIGN

This was a mixed methods cross-sectional study.

PLACE AND DURATION OF STUDY

Busolwe Town Council, Butaleja District, Eastern Uganda.

METHODOLOGY

Structured researcher administered questionnaires were administered to 434 caregivers of U5C in different parts of Butaleja district. In-depth interviews with key informants and focused group discussions with Village Health Teams and community members were conducted. Review of Health Management Information Systems records was done. STATA 15 was used to analyze the data.

RESULTS

The study found that there is a declining trend in completion of the doses of Pneumococcal vaccine (PCV) and Rotavirus vaccine. For example, in quarter 1 of 2019, out of the 312 children who started immunization, only 2 completed Rota virus immunization and only 117 completed PCV vaccinations a trend that has been observed since 2016. The factors that showed a significant association with the the fact that they gave their child at least one dose of the vaccine were having been sensitized on the current immunisation schedule(P-value = <0.001), misunderstanding that vaccine is harmful for child (P-value = 0.007), willingness to take children to vaccination (P-value = <0.001), and social factors such as family (P-value = <0.030). Gender also played a key determinant role where the children's fathers lacked knowledge on significance of immunization and thus discouraged the mothers from taking the children for immunization. Inadequate funding was also highlighted from the Focus Group Discussions.

CONCLUSION

Vaccine coverage for pneumococcus and rotavirus is still low in Butaleja district mainly due to the attitudes and perceptions of caregivers as well as the knowledge gap. There is need for extensive sensitization of all community members to enable them understand the significance of immunization. It would further be important to increase the funding of the immunization programme to intensify and ensure effectual outreaches as well as the establishment and enforcement of a policy for immunization compliance.

Effect of mobile phone text message reminders on improving completeness and timeliness of routine childhood vaccinations in North-West, Ethiopia: a study protocol for randomised controlled trial

INTRODUCTION

Non-attendance and delay in vaccination schedules remain a big challenge to healthcare workers. With the continuous growth of mobile network coverage and exponential penetration of mobile devices in the developing world, adoption of short message service has been shown to increase attendance for health services by targeting participant characteristics such as forgetfulness. Therefore, the aim of this trial is to determine the effect of mobile text message reminders on completeness and timeliness of childhood vaccination in North-West, Ethiopia.

METHODS AND ANALYSIS

A two-arm, parallel, superiority, randomised controlled trial study will be employed. The study arms are the intervention group (text message reminders plus routine care) and the control group (routine care only). Mother-infant pairs will be randomised to one of the groups during enrolment. The trial will consider a sample size of 434 mother-infant pairs with 1:1 allocation ratio. Mothers assigned to the intervention group will receive text message reminder 1 day before the scheduled vaccination visit at 6 weeks, 10 weeks, 14 weeks and at 9 months. Initially, descriptive statistics will be computed. For the primary outcome log-binomial regression model will be used to identify associated factors, and relative risk with 95% CI will be reported. Primarily, iIntention-to-treat analysis principle will be applied. STATA V.14 software will be used for the analysis.

ETHICS AND DISSEMINATION

This study obtained ethical approval from the University of Gondar Institutional Ethical Review Board. The trial findings on the effectiveness of mobile text message reminders in improving vaccination uptake will help to inform decision makers on the use of mobile health interventions in developing countries like Ethiopia. The scientific findings of the trial will also be published in reputable journals.

TRIAL REGISTRATION NUMBER

PACTR201901533237287.

Geographical variations of the associations between health interventions and all-cause under-five mortality in Uganda

Background

To reduce the under-five mortality (U5M), fine-gained spatial assessment of the effects of health interventions is critical because national averages can obscure important sub-national disparities. In turn, sub-national estimates can guide control programmes for spatial targeting. The purpose of our study is to quantify associations of interventions with U5M rate at national and sub-national scales in Uganda and to identify interventions associated with the largest reductions in U5M rate at the sub-national scale.

Methods

Spatially explicit data on U5M, interventions and sociodemographic indicators were obtained from the 2011 Uganda Demographic and Health Survey (DHS). Climatic data were extracted from remote sensing sources. Bayesian geostatistical Weibull proportional hazards models with spatially varying effects at sub-national scales were utilized to quantify associations between all-cause U5M and interventions at national and regional levels. Bayesian variable selection was employed to select the most important determinants of U5M.

Results

At the national level, interventions associated with the highest reduction in U5M were artemisinin-based combination therapy (hazard rate ratio (HRR) = 0.60; 95% Bayesian credible interval (BCI): 0.11, 0.79), initiation of breastfeeding within 1 h of birth (HR = 0.70; 95% BCI: 0.51, 0.86), intermittent preventive treatment (IPTp) (HRR = 0.74; 95% BCI: 0.67, 0.97) and access to insecticide-treated nets (ITN) (HRR = 0.75; 95% BCI: 0.63, 0.84). In Central 2, Mid-Western and South-West, largest reduction in U5M was associated with access to ITNs. In Mid-North and West-Nile, improved source of drinking water explained most of the U5M reduction. In North-East, improved sanitation facilities were associated with the highest decline in U5M. In Kampala and Mid-Eastern, IPTp had the largest associated with U5M. In Central1 and East-Central, oral rehydration solution and postnatal care were associated with highest decreases in U5M respectively.

Conclusion

Sub-national estimates of the associations between U5M and interventions can guide control programmes for spatial targeting and accelerate progress towards mortality-related Sustainable Development Goals.

Improvements in Polio Vaccination Status and Knowledge about Polio Vaccination in the CORE Group Polio Project Implementation Areas in Pastoralist and Semi-Pastoralist Regions in Ethiopia

Strengthening routine immunization is one of the four prongs of the Global Polio Eradication Initiative. Achieving this requires improving immunization coverage in hard-to-reach areas. The objectives of this analysis were to assess levels of oral polio vaccination coverage and challenges in pastoral and semi-pastoral regions in Ethiopia. The analysis included vaccination-related data for children aged 12-23 months from the 2011 Ethiopian Demographic and Health Survey (EDHS) and from surveys carried out by the CORE Group Polio Project (CGPP) in 2013, 2015, and 2017. The EDHS data were from the entire regions (states) of Somali; Oromia; Southern Nations, Nationalities, and Peoples; Benshangul-Gumuz; and Gambella, whereas the CGPP data were for portions of these states where the CGPP was working and consisted entirely of pastoralist or semi-pastoralist populations. The overall polio immunization coverage rate showed upward trend from 39.6% in the 2011 EDHS to 72.6% for 2017 survey of children in the CGPP intervention areas. The evidence suggests that the CGPP was able to achieve increasing levels of coverage in the hardest-to-reach areas of these states and that the levels were higher than those achieved in the states as a whole. The strategies used by the CGPP/Ethiopia to increase coverage appear to have been effective. Other characteristics associated with full polio immunization included mother's religion and education, whether the mother had heard about polio, knowledge on the effect of many polio vaccine doses, and age at first polio immunization.

Development of automated text-message reminder system to improve uptake of child vaccination in Ethiopia

INTRODUCTION

Non-attendance and delay for vaccination schedules remains a big challenge to healthcare workers. Among the frequently mentioned reasons for missed vaccination in children is forgetfulness of caretakers to show up in vaccination schedules. This necessitates developing an automated reminder system with integration of mobile technologies.

OBJECTIVES

This paper aimed to develop and test an automated mobile text message reminder system in the local context of Ethiopia.

METHODS

This system is developed using iterative development process through phases of requirement analysis, design, development, testing and refinement. Requirement gathering was done before development of the system. Front end application was developed using java technologies while back end applications were developed with oracle database. Finally, pilot testing of the automated reminder system was done on 30 participants.

RESULTS

The automated system has been developed based on requirements. The text message reminder system has two components: 1. Web based application for client registration and automatic reminder scheduling; 2. SMS application for automatic SMS text messaging. In the pilot testing, all the text messages (100%) were dispatched from the automated system to the respective participants. Finally, the system has shown a notification that the text messages have been sent successfully.

CONCLUSION

Text message reminder system has been developed for routine childhood immunization program in Ethiopian context. Text message based mHealth interventions should be carefully designed, developed, tested and refined before actual implementation.

Estimation of vaccination coverage from electronic healthcare records; methods performance evaluation - A contribution of the ADVANCE-project

INTRODUCTION

The Accelerated Development of VAccine beNefit-risk Collaboration in Europe (ADVANCE) is a public private collaboration aiming to develop and test a system for rapid benefit-risk (B/R) monitoring of vaccines, using existing electronic healthcare record (eHR) databases in Europe. Part of the data in such sources is missing due to incomplete follow-up hampering the accurate estimation of vaccination coverage. We compared different methods for coverage estimation from eHR databases; naïve period prevalence, complete case period prevalence, period prevalence adjusted for follow-up time, Kaplan-Meier (KM) analysis and (adjusted) inverse probability weighing (IPW).

METHODS

We created simulation scenarios with different proportions of completeness of follow-up. Both completeness independent and dependent from vaccination date and status were considered. The root mean squared error (RMSE) and relative difference between the estimated and true coverage were used to assess the performance of the different methods for each of the scenarios. We included data examples on the vaccination coverage of human papilloma virus and pertussis component containing vaccines from the Spanish BIFAP database.

RESULTS

Under completeness independent from vaccination date or status, several methods provided estimates with bias close to zero. However, when dependence between completeness of follow-up and vaccination date or status was present, all methods generated biased estimates. The IPW/CDF methods were generally the least biased. Preference for a specific method should be based on the type of censoring and type of dependence between completeness of follow-up and vaccination. Additional insights into these aspects, might be gained by applying several methods.

Text message reminders to improve infant immunization in Guatemala: A randomized clinical trial

OBJECTIVE

Millions of infants worldwide remain under-immunized and at risk for unnecessary morbidity and mortality. Text messaging may offer a low-cost solution. We aimed to evaluate text message reminders to improve infant immunization in Guatemala.

METHODS

A randomized clinical trial was conducted at four public health clinics in rural and urban Guatemala. Infants ages six weeks to six months presenting for the first visit of the primary immunization series were randomly and equally allocated to an intervention or usual care group. Intervention participants were sent three text reminders before the second and third vaccine visits. The main outcome was timeliness of the second and third visits of the primary immunization series.

RESULTS

Of 1088 families approached for enrollment between March to November 2016, 871 were eligible and 720 (82.7%) participated; only 54 families did not own a cell phone. Due to country-wide vaccine shortages, visit completion was used as a proxy for overall immunization coverage. In intention to treat analysis, both intervention and usual care groups had high rates of visit completion, but intervention participants presented on the scheduled date more often (151 [42.2%] of 358 intervention vs. 111 [30.7%] of 362 usual care participants for visit 2, p = 0.001, and 112 [34.0%] of 329 intervention vs. 90 [27.0%] of 333 usual care participants for visit 3, p = 0.05). Intervention caregivers were significantly more likely to want to receive future text message reminders for vaccines and other appointments and were more willing to pay for these reminders.

CONCLUSION

Caregivers who were sent text message reminders in urban and rural Guatemala were less delayed for their child's immunization visits and reported high user satisfaction. Text message reminders may be an effective tool to increase infant vaccination coverage in low-income settings by reminding parents to vaccinate.

TRIAL REGISTRATION

NCT02567006 at clinicaltrials.gov.

Age-appropriate vaccination coverage and its associated factors for pentavalent 1-3 and measles vaccine doses, in northeast Ethiopia: A community-based cross-sectional study

BACKGROUND

In Ethiopia, there are limited studies on age-appropriate vaccinations that children received at the recommended specific ages. Therefore, we assessed age-appropriate vaccinations coverage and its associated factors among children 12 to 23 months of age in Menz Lalo district, northeast Ethiopia.

METHODS

A community-based cross-sectional study was conducted in Menz Lalo district from March to April/2018 among 417 mothers/caregivers with children 12 to 23 months of age using simple random sampling technique. Data were collected using a pretested structured questionnaire. Information about children's vaccination status was collected from vaccination cards. Age-appropriate vaccination coverage was measured using World Health Organization vaccination schedule recommendation. Data was entered into Epi-Info7 software and exported to SPSS-20 for analysis. Four consecutive logistic regression models were performed to identify factors associated with age-inappropriate vaccinations. A P-value of ≤ 0.05 was considered to state statistically significant associations.

RESULTS

Age-appropriate vaccination coverage was 39.1% (95% CI: 34.3 to 44) for pentavalent 1, 36.3% (95% CI: 31.6 to 41.5) for pentavalent 2, 30.3% (95% CI: 25.6 to 35) for pentavalent 3 and 26.4% (95% CI: 21.7 to 31) for measles vaccine doses. Age-inappropriate pentavalent 1-3 vaccinations was associated with being male sex (AOR: 0.47, 95% CI: 0.29-0.74), lack of telephone (AOR: 2.2, 95% CI: 1.4-3.6), lack of usual caretaker (AOR: 2.6, 95% CI: 1.3-5.2), unplanned pregnancy (AOR: 1.9, 95% CI: 1.1-3.5), missing pregnant women's conference (AOR: 2.7, 95% CI: 1.3-5.7), decreasing birth order (AOR: 0.34, 95% CI: 0.17-0.68) and insufficient knowledge (AOR: 2.7, 95% CI: 1.6-4.4).

CONCLUSION

The proportions of age-appropriate vaccination coverage were low in the study area. Modifiable factors were associated with age-inappropriate vaccinations. Vaccination interventions should consider identified modifiable factors to improve age-appropriate vaccinations coverage.

Impact of vaccination delay on deaths averted by pneumococcal conjugate vaccine: Modeled effects in 8 country scenarios

Delay in vaccination from schedule has been frequently documented and varies by vaccine, dose, and setting. Vaccination delay may result in the failure to prevent deaths that would have been averted by on-schedule vaccination.

We constructed a model to assess the impact of delay in vaccination with pneumococcal conjugate vaccine (PCV) on under-five mortality. The model accounted for the week of age-specific risk of pneumococcal mortality, direct effect of vaccination, and herd protection. For each model run, a cohort of children were exposed to the risk of mortality and protective effect of PCV for each week of age from birth to age five. The model was run with and without vaccination delay and difference in number of deaths averted was calculated. We applied the model to eight country-specific vaccination scenarios, reflecting variations in observed vaccination delay, PCV coverage, herd effect, mortality risk, and vaccination schedule. As PCV is currently being scaled up in India, we additionally evaluated the impact of vaccination delay in India under various delay scenarios and coverage levels.

We found deaths averted by PCV with and without delay to be comparable in all of the country scenarios when accounting for herd protection. In India, the greatest relative difference in deaths averted was observed at low coverage levels and greatest absolute difference was observed around 60% vaccination coverage. Under moderate delay scenarios, vaccination delay had modest impact on deaths averted by PCV in India across levels of coverage or vaccination schedule. Without accounting for herd protection, vaccination delay resulted in much greater failure to avert deaths.

Our model suggests that realistic vaccination delay has a minimal impact on the number of deaths averted by PCV when accounting for herd effect. High population coverage can largely over-ride the deleterious effect of vaccination delay through herd protection.

Vaccination timeliness and delay in low- and middle-income countries: a systematic review of the literature, 2007-2017

Background: Traditional measurements of vaccine coverage at specific ages can mask poor vaccine timeliness. However, optimal measurement of timing is unclear due to variations in countries’ recommended vaccination schedules and lack of a commonly accepted standard for “timeliness”. We conducted a systematic review of literature on vaccine timeliness and delay in low- and middle-income countries from 2007 to 2017.

Methods: A search of articles published between January 1 2007 and December 31 2017, was performed in PubMed, EBSCOhost, and Embase.

Results: 67 papers were included, of which 83% used a categorical measure of delay and 41% evaluated continuous delay. The most common age at assessment was 1 month, with earlier age benchmarks typically used with birth doses.

Conclusions: Categorical definitions of vaccination timing vary widely, with benchmarks of delay varying from days to weeks to months. Use of a continuous measure of vaccine delay may be more informative and comparable.

Vaccination coverage and factors associated with routine childhood vaccination uptake in rural Vellore, southern India, 2017

BACKGROUND

Vellore district in southern India was selected for intensified immunization efforts through India's Mission Indradhanush campaign based on 74% coverage in the National Family Health Survey in 2015. As rural households rely almost entirely on the Universal Immunization Program (UIP), we assessed routine immunization coverage and factors associated with vaccination status of children in rural Vellore.

METHODS

We conducted a cross-sectional household survey among parents or primary caretakers of children aged 12-23 months during August-September 2017 using two-stage, EPI cluster sampling. We verified vaccination histories from vaccination cards and collected data on sociodemographic and non-socio-demographic characteristics by using mobile data capture. Associations with vaccination status were examined with univariate and multivariate logistic regression models.

RESULTS

A total of 643 children were included. Coverage of BCG, third dose pentavalent/DPT, measles/MR vaccines and full vaccination (BCG, three doses of polio and pentavalent/DPT and measles/MR vaccines) among children with vaccination cards (n = 606) was 94%, 96%, 93% and 84%, respectively. Of children with vaccination cards, 70.8% had received all recommended doses according to the UIP schedule. No socio-demographic differences were identified, but parents' familiarity with the schedule (Adjusted Prevalence Odds Ratio (aPOR): 2.06, 95%CI = 1.26-3.38) and receiving information on recommended vaccinations during antenatal visits (aPOR: 2.16, 95% CI = 1.13-4.12) were significantly associated with full vaccination status of the children.

CONCLUSIONS

We found higher UIP antigen coverage and proportion of fully vaccinated children than previously reported from rural Vellore. However, adherence to the recommended schedule was still not optimal. Our study highlights the potential of improving parental awareness of vaccination schedule and targeting health education interventions at pregnant women during antenatal visits to sustain and improve routine immunization coverage.

Age appropriateness of vaccination with recommended childhood vaccines in Sri Lanka

Vaccination status is conventionally measured by up-to-date coverage. This method does not take in to account whether the vaccines were received at the correct age and interval which is essential for optimal disease protection. Sri Lanka – a lower middle-income country in the Indian Ocean, has previously presented with high vaccination coverage for all childhood vaccines. However, few studies investigating timeliness of vaccinations have until now been carried out in Sri Lanka.

Aim: This study was carried out to investigate the individual coverage and age appropriateness of vaccination, in two different demographic settings in Anuradhapura district, Sri Lanka. The study of cross-sectional descriptive design included 633 children born in 2011. Public Health Midwives kept hand-written documentation of the birth and vaccination dates on each child in her geographic area. Vaccination ages were then compared to the timelines of vaccination provided by the Epidemiology Unit of Sri Lanka.

The vaccination coverage for all antigens was 97.5% (94.2–99.7%) at age 5–6 years. Timeliness of doses was between 65.0 and 88.6 % (median 80.7%; 65.0–88.6) and significantly lower in the urban population compared to the rural. The present study shows that the vaccine coverage in both urban and rural areas in Sri Lanka was high and that the timeliness predominantly followed national recommendations.

Vaccination timeliness among newborns and infants in Ethiopia

BACKGROUND

We characterize the risk factors for delayed polio dose 1, diphtheria-tetanus-pertussis (DTP) dose 1, pentavalent dose 1, and measles dose 1 in Ethiopian infants. We also examine the interaction between institutional delivery and demographic factors on the birth doses of the BCG and polio vaccines to better understand factors influencing vaccination.

METHODS

Using the 2011 Ethiopia Demographic and Health Survey, we calculated the distribution of the study population across different demographic and vaccination characteristics. We computed acceleration factors using a multivariable accelerated failure time model with a Weibull distribution to account for left and right censoring. For the birth doses, we further specified an interaction term between institutional delivery and every other a priori specified independent variable to test whether institutional delivery modifies sociodemographic disparities in vaccination timeliness.

RESULTS

Low wealth status, home delivery, and ethnicity are risk factors for delayed vaccination of polio 1, DPT 1, pentavalent 1, and measles 1. Religion is a risk factor for measles 1 vaccination delay and rural residence are risk factors for delayed DPT1 and polio 1 doses. For birth doses of polio and BCG, institutional delivery attenuated many sociodemographic disparities in vaccination delay, except for urbanicity, which showed rural dwellers with more delay than urban dwellers with an institutional vs home birth.

CONCLUSIONS

Less delayed vaccination among children with institutional deliveries highlights the importance of perinatal care and the potential for promoting healthy behaviors to parents. Persistent disparities between urban and rural residents, even among those with institutional births, can be targeted for future interventions. Timely vaccination is key to prevention of unnecessary childhood mortality.

Vaccination timeliness and co-administration among Kenyan children

BACKGROUND

Timely administration of recommended vaccines requires children to have multiple vaccines co-administered in the first year of life. The objectives of this study were to estimate the proportion of timely vaccinations and the proportion of co-administered vaccines, and to assess the relationship between vaccine co-administration and vaccine timeliness in Kenyan children.

METHODS

Using the 2014 Kenyan Demographic and Health Survey (DHS), we calculated the proportion of children who received co-administered and timely vaccine doses. Co-administration was defined as doses administered on the same day with dates recorded on vaccination cards. Vaccines were considered timely if given within four days before to four weeks after the recommended interval for administration.

RESULTS

10,385 children aged 1-4 years in the Kenyan 2014 DHS dataset had vaccination cards which comprised the study sample. Analysis revealed wide a range for receipt of timely doses, from 90.2% for OPV0 to 56.0% for Measles. Co-administration of the 6-week dose was associated with 2.81 times higher odds of a timely Penta dose 1 (95% CI: 2.28, 3.46) and birth-dose co-administration was associated with a substantial increase in timely BCG vaccination: AOR 7.43 (95% CI: 6.31, 8.75).

CONCLUSIONS

Though vaccine coverage in Kenya was high, timely vaccination was markedly low, with resultant implications for population immunity and potential spread of communicable diseases in unvaccinated infants. Co-administration of vaccines, place of residence, wealth index, and child age were consistently related to the odds of timely vaccine receipt. These relationships reinforce the importance of dedicating resources to programs that educate low socio-economic groups about the importance of vaccine co-administration.

Coverage of childhood vaccination among children aged 12-23 months, Tamil Nadu, 2015, India

Background & objectives:

District-Level Household Survey-4 (DLHS-4) indicated that during 2012-2013, only 56 per cent of children aged 12-23 months in Tamil Nadu were fully vaccinated, which were lesser than those reported in earlier national surveys. We, therefore, conducted cluster surveys to estimate coverage of childhood vaccination in the State, and also to identify the factors associated with low coverage.

Methods:

Cross-sectional surveys were conducted in 15 strata [municipal corporation non-slum (n=1), municipal corporation slum (n=1), hilly (n=1), rural (n=6) and urban (n=6)]. From each stratum, 30 clusters were selected using probability proportional to the population size linear systematic sampling; seven children aged 12-23 months were selected from each cluster and their mothers/care-takers were interviewed to collect information about vaccination status of the child. A child was considered fully vaccinated if he/she received bacillus Calmette-Guérin (BCG), three doses of pentavalent, three doses of oral polio vaccine and one dose of measles vaccine, and appropriately vaccinated if all vaccine doses were given at right age and with right interval. Further, coverage of fully vaccinated children (FVC) as per vaccination cards or mothers’ recall, validated coverage of FVC (V-FVC) among those having cards, and coverage of appropriately vaccinated children (AVC) were estimated using survey data analysis module with appropriate sampling weights.

Results:

A total of 3150 children were surveyed, of them 2528 (80.3%) had vaccination card. The weighted coverage of FVC, V-FVC and AVC in the State was 79.9 per cent [95% confidence interval (CI): 78.2-81.5], 78.8 per cent (95% CI: 76.9-80.5) and 69.7 per cent (95% CI: 67.7-71.7), respectively. The coverage of individual vaccine ranged between 84 per cent (measles) and 99.8 per cent (BCG). About 12 per cent V-FVC were not vaccinated as per the vaccination schedule.

Interpretation & conclusions:

The coverage of FVC in Tamil Nadu was high, with about 80 per cent children completing primary vaccination. Efforts to increase vaccination coverage in the State need to focus on educating vaccinators about the need to adhere to the national vaccination schedule and strengthening supervision to ensure that children are vaccinated appropriately.

Vaccination Timeliness at Age 24 Months in Michigan Children Born 2006-2010

INTRODUCTION

Delays in vaccination can stymie the development of herd immunity, and a large proportion of children in the U.S. are known not to receive vaccines on time. This study quantifies delays in vaccination, compares vaccination timeliness to the proportion of children vaccinated, and evaluates the impact of combination vaccine use and timely administration of hepatitis B vaccine birth dose on vaccine timeliness among Michigan children.

METHODS

This retrospective cohort study used data from the Michigan Care Improvement Registry-the state immunization information system-for children born 2006-2010. Children aged 24 months as of December 31, 2012, were included. The proportion of children with timely administration of vaccine doses was calculated, and the mean days of vaccination delay with SD were reported.

RESULTS

Among 620,592 Michigan children, 42.2% had received all vaccines, but only 13.2% were vaccinated on time by age 24 months. Children's vaccinations were delayed an average of 59.2 (SD=91.2) days by age 24 months for all recommended vaccine doses. Children who received a timely hepatitis B vaccine birth dose or who received a combination vaccine had less delay in vaccination.

CONCLUSIONS

Michigan children have high vaccination coverage based on standard measures but few receive these vaccines on time. Promoting use of combination vaccines may improve parental compliance with timely vaccination of children.

Timeliness of childhood vaccination in the Federated States of Micronesia

BACKGROUND

Vaccination coverage is typically measured as the proportion of individuals who have received recommended vaccine doses by the date of assessment. This approach does not provide information about receipt of vaccines by the recommended age, which is critical for ensuring optimal protection from vaccine-preventable diseases (VPDs).

OBJECTIVE

To assess vaccination timeliness in the Federated States of Micronesia (FSM), and the projected impact of suboptimal vaccination in the event of an outbreak.

METHODS

Timeliness of the 4th dose of diphtheria, tetanus, and acellular pertussis vaccine (DTaP) and 1st dose of measles, mumps, and rubella vaccine (MMR) among children 24-35 months was assessed in FSM. Both doses are defined as on time if administered from 361 through 395 days in age. Timeliness was calculated by one-way frequency analysis, and dose delays, measured in months after recommended age, were described using inverse Kaplan-Meier analysis. A time-series susceptible-exposed-infected-recovery (TSEIR) model simulated measles outbreaks in populations with on time and late vaccination.

RESULTS

Total coverage for the 4th dose of DTaP ranged from 36.6% to 98.8%, and for the 1st dose of MMR ranged from 80.9% to 100.0% across FSM states. On time coverage for the 4th dose of DTaP ranged from 3.2% to 52.3%, and for the 1st dose of MMR ranged from 21.1% to 66.9%. Maximum and median dose delays beyond the recommended age varied by state. TSEIR models predicted 10.8-13.7% increases in measles cases during an outbreak based on these delays.

CONCLUSIONS

In each of the FSM states, a substantial proportion of children received DTaP and MMR doses outside the recommended timeframe. Children who receive vaccinations later than recommended remain susceptible to VPDs during the period they remain unvaccinated, which may have a substantial impact on health systems during an outbreak. Immunization programs should consider vaccination timeliness in addition to coverage as a measure of susceptibility to VPDs in young children.

Timeliness of Childhood Primary Immunization and Risk Factors Related with Delays: Evidence from the 2014 Zhejiang Provincial Vaccination Coverage Survey

Background: this study aimed to assess both immunization coverage and timeliness, as well as reasons for non-vaccination, and identity the risk factors of delayed immunization, for the vaccines scheduled during the first year of life, in Zhejiang province, east China. Methods: A cluster survey among children aged 24-35 months was conducted. Demographic information and socio-economic characteristics of the selected child, the mother, and the household were collected. Immunization data were transcribed from immunization cards. Timeliness was assessed with Kaplan-Meier analysis for each vaccine given before 12 months of age, based on the time frame stipulated by the expanded program on immunization of China. Cox proportional hazard regression was applied to identify risk factors of delayed immunization. Results: A total of 2772 eligible children were surveyed. The age-appropriate coverage ranged from 25.4% (95% CI: 23.7-27.0%) for Bacillus Calmette-Guerin (BCG) to 91.3% (95% CI: 90.2-92.3%) for the first dose of oral poliomyelitis vaccine (OPV1). The most frequent reason for non-vaccination was parent's fear of adverse events of immunization. Delayed immunizations were associated with mother having a lower education level, mother having a job, delivery at home, increasing number of children per household, and having a lower household income. Conclusions: Although the timeliness of immunization has improved since 2011, necessary steps are still needed to achieve further improvement. Timeliness of immunization should be considered as another important indicator of expanded program on immunization (EPI) performance. Future interventions on vaccination coverage should take into consideration demographic and socio-economic risk factors identified in this study. The importance of adhering to the recommended schedule should be explained to parents.

Risk factors for measles death: Kyegegwa District, western Uganda, February-September, 2015

BACKGROUND

On 18 August 2015, Kyegegwa District reported eight deaths during a measles outbreak to the Uganda Ministry of Health (MoH). We investigated this death cluster to verify the cause, identify risk factors, and inform public health interventions.

METHODS

We defined a probable measles case as onset of fever and generalised rash in a Kyegegwa District resident from 1 February - 15 September 2015, plus ≥1 of the following: coryza, conjunctivitis, and cough. A confirmed measles case was a probable case with measles-specific IgM positivity. A measles death was a death of a probable or confirmed case-person. We conducted an active case-finding to identify measles patients who survived or died. In a case-control study, we compared risk factors between 16 measles patients who died (cases) and 48 who survived (controls), matched by age (±4 years) and village of residence.

RESULTS

We identified 94 probable measles cases, 10 (11%) were confirmed by positive measles-specific IgM. Of the 64 probable measles patients aged <5 years, 16 died (case-fatality rate = 25%). In the case-control study, no history of vaccination against measles was found in 94% (15/16) among the case-persons (i.e., measles patients who died) and 54% (26/48) among the controls (i.e., measles patients who survived) (OR_M-H = 12; 95% CI = 1.6-104), while 56% (9/16) of case-persons and 67% (17/48) of controls (OR_M-H = 2.3; 95% CI =0.74-7.4) did not receive vitamin A supplementation during illness. 63% (10/16) among the case-persons and 6.3% (3/48) of the controls (OR_M-H = 33; 95% CI = 6.8-159) were not treated for measles illness at a health facility (a proxy for more appropriate treatment), while 38% (6/16) of the case-persons and 25% (12/48) of the controls (OR_M-H = 2.5; 95% CI = 0.67-9.1) were malnourished.

CONCLUSION

Lack of vaccination and no treatment in a health facility increased the risk for measles deaths. The one-dose measles vaccination currently in the national vaccination schedule had a protective effect against measles death. We recommended enhancing measles vaccination and adherence to measles treatment guidelines.

Vaccination coverage and immunization timeliness among children aged 12-23 months in Senegal: a Kaplan-Meier and Cox regression analysis approach

Introduction

Expanded programme on immunizations in resource-limited settings currently measure vaccination coverage defined as the proportion of children aged 12-23 months that have completed their vaccination. However, this indicator does not address the important question of when the scheduled vaccines were administered. We assessed the determinants of timely immunization to help the national EPI program manage vaccine-preventable diseases and impact positively on child survival in Senegal.

Methods

Vaccination data were obtained from the Demographic and Health Survey (DHS) carried out across the 14 regions in the country. Children were aged between 12-23 months. The assessment of vaccination coverage was done with the health card and/or by the mother’s recall of the vaccination act. For each vaccine, an assessment of delay in age-appropriate vaccination was done following WHO recommendations. Additionally, Kaplan-Meier survival function was used to estimate the proportion vaccinated by age and cox-proportional hazards models were used to examine risk factors for delays.

Results

A total of 2444 living children between 12–23 months of age were included in the analysis. The country vaccination was below the WHO recommended coverage level and, there was a gap in timeliness of children immunization. While BCG vaccine uptake was over 95%, coverage decreased with increasing number of Pentavalent vaccine doses (Penta 1: 95.6%, Penta 2: 93.5%: Penta 3: 89.2%). Median delay for BCG was 1.7 weeks. For polio at birth, the median delay was 5 days; all other vaccine doses had median delays of 2-4 weeks. For Penta 1 and Penta 3, 23.5% and 15.7% were given late respectively. A quarter of measles vaccines were not administered or were scheduled after the recommended age. Vaccinations that were not administered within the recommended age ranges were associated with mothers’ poor education level, multiple siblings, low socio-economic status and living in rural areas.

Conclusion

A significant delay in receipt of infant vaccines is found in Senegal while vaccine coverage is suboptimal. The national expanded program on immunization should consider measuring age at immunization or using seroepidemiological data to better monitor its impact.

Immunisation timeliness in a cohort of urban Aboriginal and Torres Strait Islander children

BACKGROUND

To evaluate immunisation coverage, timeliness and predictors of delayed receipt in urban Australian Indigenous children during the first 18 months of life.

METHODS

Cross-sectional retrospective analysis of data collected from 140 Australian Indigenous children aged < 5 years at the time of enrolment in a prospective cohort study on respiratory illness between 14 February 2013 and 28 January 2015. Children were recruited through an urban community primary health care centre in the Northern suburbs of Brisbane, Queensland.

RESULTS

The proportion of children with completed immunisation schedules was 50 of 105 (47.6%) at 7 months, 30 of 85 (35.3%) at 13 months and 12 of 65 (18.5%) at 19 months. Timely receipt of diphtheria-tetanus-pertussis decreased from 78.4% at 2 months of age to 63.7 and 59.3% at 4 and 6 months respectively. Amongst the 105 parents/guardians with children ≥7 months at enrolment, 71 (67.6%) incorrectly reported their child's immunisation status. Delayed vaccine receipt was significantly associated (p ≤0.05) with having multiple children in the household, mother's unemployment and premature birth.

CONCLUSIONS

Coverage and timeliness among this population is suboptimal and decreases as children age. Parent/guardian reporting of vaccination status was unreliable. Children of unemployed mothers and those with multiple siblings should be targeted to improve community immunisation timeliness due to a greater risk of vaccination delay. High quality trials, conducted in several settings to account for the diversity of Australian Indigenous communities are urgently needed to identify culturally appropriate, effective and sustainable strategies to improve immunisation targets in children.

Health in a fragile state: a five-year review of mortality patterns and trends at Somalia's Banadir Hospital

Background

The recurrent civil conflict in Somalia has impeded progress toward improving health and health care, with lack of data and poor performance of health indicators. This study aimed at making inference about Banadir region by exploring morbidity and mortality trends at Banadir Hospital. This is one of the few functional hospitals during war.

Methods

A retrospective analysis was conducted with data collected at Banadir Hospital for the period of January 2008–December 2012. The data were aggregated from patient records and summarized on a morbidity and mortality surveillance form with respect to age groups and stratified by sex. The main outcome was the number of patients that died in the hospital. Chi-square tests were used to evaluate the association between sex and hospital mortality.

Results

Conditions of infectious origin were the major presentations at the hospital. The year 2011 recorded the highest number of cases of diarrhea and mortality due to diarrhea. The stillbirth rate declined during the study period from 272 to 48 stillbirths per 1,000 live births by 2012. The sum of total cases that were attended to at the hospital by the end of 2012 was four times the number at the baseline year of the study in 2008; however, the overall mortality rate among those admitted declined between 2008 and 2012.

Conclusion

There was reduction in patient mortality at the hospital over the study period. Data from Banadir Hospital are consistent with findings from Banadir region and could give credible public health reflections for the region given the lack of data on a population level.

Vaccination Timeliness in Children Under India's Universal Immunization Program

BACKGROUND

India has the highest number of deaths among children younger than 5 years of age globally; the majority are from vaccine preventable diseases. Untimely vaccination unnecessarily prolongs susceptibility to disease and contributes to the burden of childhood morbidity and mortality, yet there is scarce literature on vaccination delays. The aim of this study is to characterize the timeliness of childhood vaccinations administered under India's routine immunization program using a novel application of an existing statistical methodology.

METHODS

This study utilized the district level household and facility survey data, 2008 from India using vaccination data from children with and without immunization cards. Turnbull estimator of the cumulative distribution function was used to estimate the probability of vaccination at each age. Timeliness of Bacille Calmette-Guerin (BCG), all 3 doses of diphtheria, pertussis and tetanus vaccine (DPT) and measles-containing vaccine (MCV) were considered for this analysis.

RESULTS

Vaccination data on 268,553 children who were 0-60 months of age were analyzed; timely administration of BCG, DPT3 and MCV occurred in 31%, 19% and 34% of children, respectively. The estimated vaccination probability plateaued for DPT and BCG around the age of 24 months, whereas MCV uptake increased another 5% after 24 months of age. The 5-year coverage of BCG, DPT3 and MCV in Indian children was 87%, 63% and 76%, respectively.

CONCLUSIONS

Lack of timely administration of key childhood vaccines, especially DPT3 and MCV, remains a major challenge in India and likely contributes to the significant burden of vaccine preventable disease-related morbidity and mortality in children.

Effects of an exclusive breastfeeding intervention for six months on growth patterns of 4-5 year old children in Uganda: the cluster-randomised PROMISE EBF trial

Background

Breastfeeding promotion is regarded as one of the most effective interventions to improve child health, and could reduce under-5-mortality by 8 % globally. Few studies have assessed the health outcomes beyond infancy of interventions promoting exclusive breastfeeding.

Methods

This study assessed growth in under-five children who participated in a cluster-randomised trial in Eastern Uganda (ClinicalTrials.gov.no.NCT00397150). In the intervention arm, peer counsellors promoted exclusive breastfeeding during the first 6 months of infancy. There were no interventions after 6 months of age. Mother-infant pairs were interviewed at visits scheduled at 3, 6, 12 and 24 weeks after birth and follow-up visits at 2 and 5 years, with 765 included in the analyses.

Results

The mean length/height-for-age and weight-for-age-z-score (HAZ, WAZ) decreased with increasing age in both the intervention and control arms. At the three weeks visit, HAZ in the intervention was −0.45 (−0.68;−0.21) and −0.32 (−0.56;−0.07) in the control arm. At the 2 year follow-up, the mean HAZ in the intervention was −1.85 (95 % CI −1.97;−1.73) compared to −1.61 (−1.87;−1.34) in the control. Similarly, at the 5 year follow-up, the mean HAZ in the intervention was −1.78 (−2.08;−1.47) compared to −1.53 (−1.79;−1.28) in the control arm. At the 2 year follow-up visit, 139 (45 %) were stunted (HAZ<−2) in the intervention compared to 109 (37 %) in the control arm, odds ratio (OR) 1.7 (1.1;2.4). Underweight (WAZ<−2) was also more common in the intervention arm than in the control at the five years follow-up (OR 1.7 (1.0;2.8)), with a mean WAZ of −1.28 (−1.47;−1.08) and −1.06 (−1.19;−0.92) in the intervention and control arm, respectively.

Conclusion

While stunting was widespread at 2 and 5 years of age in both arms, it was more common in the intervention arm. It is questionable whether community-based support from lay people with short training and focussing only on exclusive breastfeeding, is an appropriate strategy to improve child health and development.

Trial registration

ClinicalTrials.gov.no.NCT00397150. Registered 7th of November 2006.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-016-3234-3) contains supplementary material, which is available to authorized users.

Barriers to timely administration of birth dose vaccines in The Gambia, West Africa

OBJECTIVE

Although vaccine coverage in infants in sub-Saharan Africa is high, this is estimated at the age of 6-12 months. There is little information on the timely administration of birth dose vaccines. The objective of this study was to assess the timing of birth dose vaccines (hepatitis B, BCG and oral polio) and reasons for delayed administration in The Gambia.

METHODS

We used vaccination data from the Farafenni Health and Demographic Surveillance System (FHDSS) between 2004 and 2014. Coverage was calculated at birth (0-1 day), day 7, day 28, 6 months and 1 year of age. Logistic regression models were used to identify demographic and socio-economic variables associated with vaccination by day 7 in children born between 2011 and 2014.

RESULTS

Most of the 10,851 children had received the first dose of hepatitis B virus (HBV) vaccine by the age of 6 months (93.1%). Nevertheless, only 1.1% of them were vaccinated at birth, 5.4% by day 7, and 58.4% by day 28. Vaccination by day 7 was associated with living in urban areas (West rural: adjusted OR (AOR)=6.13, 95%CI: 3.20-11.75, east rural: AOR=6.72, 95%CI: 3.66-12.33) and maternal education (senior-educations: AOR=2.43, 95%CI: 1.17-5.06); and inversely associated with distance to vaccination delivery points (≧2km: AOR=0.41, 95%CI: 0.24-0.70), and Fula ethnicity (AOR=0.60, 95%CI: 0.40-0.91).

CONCLUSION

Vaccine coverage in The Gambia is high but infants are usually vaccinated after the neonatal period. Interventions to ensure the implementation of national vaccination policies are urgently needed.

Fully immunized child: coverage, timing and sequencing of routine immunization in an urban poor settlement in Nairobi, Kenya

BACKGROUND

More efforts have been put in place to increase full immunization coverage rates in the last decade. Little is known about the levels and consequences of delaying or vaccinating children in different schedules. Vaccine effectiveness depends on the timing of its administration, and it is not optimal if given early, delayed or not given as recommended. Evidence of non-specific effects of vaccines is well documented and could be linked to timing and sequencing of immunization. This paper documents the levels of coverage, timing and sequencing of routine childhood vaccines.

METHODS

The study was conducted between 2007 and 2014 in two informal urban settlements in Nairobi. A total of 3856 children, aged 12-23 months and having a vaccination card seen were included in analysis. Vaccination dates recorded from the cards seen were used to define full immunization coverage, timeliness and sequencing. Proportions, medians and Kaplan-Meier curves were used to assess and describe the levels of full immunization coverage, vaccination delays and sequencing.

RESULTS

The findings indicate that 67 % of the children were fully immunized by 12 months of age. Missing measles and third doses of polio and pentavalent vaccine were the main reason for not being fully immunized. Delays were highest for third doses of polio and pentavalent and measles. About 22 % of fully immunized children had vaccines in an out-of-sequence manner with 18 % not receiving pentavalent together with polio vaccine as recommended.

CONCLUSIONS

Results show higher levels of missed opportunities and low coverage of routine childhood vaccinations given at later ages. New strategies are needed to enable health care providers and parents/guardians to work together to increase the levels of completion of all required vaccinations. In particular, more focus is needed on vaccines given in multiple doses (polio, pentavalent and pneumococcal conjugate vaccines).

Predictors of Uptake and Timeliness of Newly Introduced Pneumococcal and Rotavirus Vaccines, and of Measles Vaccine in Rural Malawi: A Population Cohort Study

BACKGROUND

Malawi introduced pneumococcal conjugate vaccine (PCV13) and monovalent rotavirus vaccine (RV1) in 2011 and 2012 respectively, and is planning the introduction of a second-dose measles vaccine (MV). We assessed predictors of availability, uptake and timeliness of these vaccines in a rural Malawian setting.

METHODS

Commencing on the first date of PCV13 eligibility we conducted a prospective population-based birth cohort study of 2,616 children under demographic surveillance in Karonga District, northern Malawi who were eligible for PCV13, or from the date of RV1 introduction both PCV13 and RV1. Potential predictors of vaccine uptake and timeliness for PCV13, RV1 and MV were analysed respectively using robust Poisson and Cox regression.

RESULTS

Vaccine coverage was high for all vaccines, ranging from 86.9% for RV1 dose 2 to 95.4% for PCV13 dose 1. Median time delay for PCV13 dose 1 was 17 days (IQR 7-36), 19 days (IQR 8-36) for RV1 dose 1 and 20 days (IQR 3-46) for MV. Infants born to lower educated or farming mothers and those living further away from the road or clinic were at greater risk of being not fully vaccinated and being vaccinated late. Delays in vaccination were also associated with non-facility birth. Vaccine stock-outs resulted in both a delay in vaccine timeliness and in a decrease in completion of schedule.

CONCLUSION

Despite high vaccination coverage in this setting, delays in vaccination were common. We identified programmatic and socio-demographic risk factors for uptake and timeliness of vaccination. Understanding who remains most vulnerable to be unvaccinated allows for focussed delivery thereby increasing population coverage and maximising the equitable benefits of universal vaccination programmes.

Immunization Coverage Surveys and Linked Biomarker Serosurveys in Three Regions in Ethiopia

Objective

Demographic and health surveys, immunization coverage surveys and administrative data often divergently estimate vaccination coverage, which hinders pinpointing districts where immunization services require strengthening. We assayed vaccination coverage in three regions in Ethiopia by coverage surveys and linked serosurveys.

Methods

Households with children aged 12–23 (N = 300) or 6–8 months (N = 100) in each of three districts (woredas) were randomly selected for immunization coverage surveys (inspection of vaccination cards and immunization clinic records and maternal recall) and linked serosurveys. IgG-ELISA serologic biomarkers included tetanus antitoxin ≥ 0.15 IU/ml in toddlers (receipt of tetanus toxoid) and Haemophilus influenzae type b (Hib) anti-capsular titers ≥ 1.0 mcg/ml in infants (timely receipt of Hib vaccine).

Findings

Coverage surveys enrolled 1,181 children across three woredas; 1,023 (87%) also enrolled in linked serosurveys. Administrative data over-estimated coverage compared to surveys, while maternal recall was unreliable. Serologic biomarkers documented a hierarchy among the districts. Biomarker measurement in infants provided insight on timeliness of vaccination not deducible from toddler results.

Conclusion

Neither administrative projections, vaccination card or EPI register inspections, nor parental recall, substitute for objective serological biomarker measurement. Including infants in serosurveys informs on vaccination timeliness.

Do Maternal Knowledge and Attitudes towards Childhood Immunizations in Rural Uganda Correlate with Complete Childhood Vaccination?

Improving childhood vaccination coverage and timeliness is a key health policy objective in many developing countries such as Uganda. Of the many factors known to influence uptake of childhood immunizations in under resourced settings, parents' understanding and perception of childhood immunizations has largely been overlooked. The aims of this study were to survey mothers' knowledge and attitudes towards childhood immunizations and then determine if these variables correlate with the timely vaccination coverage of their children. From September to December 2013, we conducted a cross-sectional survey of 1,000 parous women in rural Sheema district in southwest Uganda. The survey collected socio-demographic data and knowledge and attitudes towards childhood immunizations. For the women with at least one child between the age of one month and five years who also had a vaccination card available for the child (N = 302), the vaccination status of this child was assessed. 88% of these children received age-appropriate, on-time immunizations. 93.5% of the women were able to state that childhood immunizations protect children from diseases. The women not able to point this out were significantly more likely to have an under-vaccinated child (PR 1.354: 95% CI 1.018-1.802). When asked why vaccination rates may be low in their community, the two most common responses were "fearful of side effects" and "ignorance/disinterest/laziness" (44% each). The factors influencing caregivers' demand for childhood immunizations vary widely between, and also within, developing countries. Research that elucidates local knowledge and attitudes, like this study, allows for decisions and policy pertaining to vaccination programs to be more effective at improving child vaccination rates.

Risk Factors of Delay Proportional Probability in Diphtheria-tetanus-pertussis Vaccination of Iranian Children; Life Table Approach Analysis

Despite success in expanded program immunization for an increase in vaccination coverage in the children of world, timeliness and schedule of vaccination remains as one of the challenges in public health. This study purposed to demonstrate the related factors of delayed diphtheria-tetanus-pertussis (DTP) vaccination using life table approach. A historical cohort study conducted in the poor areas of five large Iran cities. Totally, 3610 children with 24-47 months old age who had documented vaccination card were enrolled. Time of vaccination for the third dose of DTP vaccine was calculated. Life table survival was used to calculate the proportional probability of vaccination in each time. Wilcoxon test was used for the comparison proportional probability of delayed vaccination based on studies factors. The overall median delayed time for DTP3 was 38.52 days. The Wilcoxon test showed that city, nationality, education level of parents, birth order and being in rural areas are related to the high probability of delay time for DTP3 vaccination (P < 0. 001). Moreover, child gender and parent's job were not significant factors (P > 0.05). Being away from the capital, a high concentration of immigrants in the city borders with a low socioeconomic class leads to prolonged delay in DTP vaccination time. Special attention to these areas is needed to increase the levels of parental knowledge and to facilitate access to the health services care.

Survival Analysis for Predictive Factors of Delay Vaccination in Iranian Children

Background:

Today, beside immunization coverage the age appropriate vaccination is another helpful index in public health. Evidences have shown that high immunization coverage rates do not necessarily imply age-appropriate vaccination status. The current study aimed to show the predictive factors of delayed vaccination by survival models.

Methods:

A historical cohort study conducted on 3610 children aged between 24 and 47 months who was living in the suburbs of five big cities of Iran. Time of delay in vaccination of first dose of mumps-measles-rubella (MMR) was calculated from date of vaccination minus age appropriate time according to vaccine card. Kaplan–Maier and Log rank tests were used for comparison the median of delay time. For controlling of confounding variables, multivariate cox model was used and hazard ratio with 95% confidence interval (95%) was reported.

Results:

The mean ± standard deviation and median interquartile range of delay time was 38.34 ± 73.1 and 16 (11–31) days in delayed group. The Log rank test showed that city of living, nationality, parents’ education, and birth order are related with prolonged delay time in MMR vaccination (P < 0.05). Nevertheless, child sex, prior living place (rural or city) and parent's job are not related with delay time of vaccination (P > 0.05). Cox regression showed that city of living, mother education, and nationality are the most predictive factors of delay time duration in MMR vaccination.

Conclusions:

Delay time duration of vaccination increased by faring from capital to the east south. Moreover, concentration of foreign immigrants in big cities and low level of mother education are the most predictors of delayed vaccination. Educational intervention should focus on immigrants and mothers with low education level.

From current vaccine recommendations to everyday practices: An analysis in five sub-Saharan African countries

BACKGROUND

Estimates of WHO and UNICEF vaccination coverage may provide little insight into the extent to which vaccinations are administered on time. Yet, lack of adherence to the recommended age to receive a specific vaccination may have detrimental health consequences. For example, delays in receiving vaccination will prolong the risk of lack of protection, often when disease risk is highest, such as during early infancy. We estimated the reported age at vaccination, and vaccine coverage at different ages in children from five sub-Saharan African countries.

METHODS

We analyzed data from the latest Demographic and Health Programme databases available for Burkina Faso 2010 (n=15,044 observations), Ghana 2008 (n=2992), Kenya 2008-9 (n=6079), Senegal 2010-11 (n=12,326), and Tanzania 2010 (n=8023). We assessed, amongst vaccinees, the exact age when vaccine was administered for the three infant doses of pentavalent vaccine (DTP) and the first dose of measles-containing-vaccine (MCV), as well as the proportion of children immunized with these antigens by a certain age. Vitamin A supplementation (VAS) coverage was evaluated as a potential contact visit for vaccine introduction.

RESULTS

For all DTP doses, the median intervals between recommended and actual ages of receiving vaccination ranged from 12, 17 and 23 days in Kenya, to 22, 33 and 45 days in Senegal. MCV was mostly given during the recommended age of 9 months. In each country, there was a large discrepancy in the median age at DTP vaccination between regions. VAS coverage in young children ranged from 30.3% in Kenya to 78.4% in Senegal, with large variations observed between areas within each study country.

CONCLUSION

In the context of new vaccine introduction, age of children at vaccination should be monitored to interpret data on vaccine-preventable disease burden, vaccine effectiveness, and vaccine safety, and to adapt targeted interventions and messages.

Factors associated with delayed measles vaccination among children in Shenzhen, China: a case-control study

A delay in the first dose of measles-containing vaccine (MCV1) may contribute to outbreaks of measles, resulting in a high age-specific incidence in infants<1 y of age. To determine the factors associated with delayed MCV1 vaccinations, we used data from the China Information Management System for Immunization Programming. Additionally, the parents/guardians of 430 children whose MCV1 vaccinations were delayed, as well as the parents/guardians of 424 children who received timely vaccinations, were surveyed by telephone. Children were less likely to receive timely MCV1 vaccinations if they belonged to an immigrant group, were male, had poor health status, had a father whose occupation e.g., a manager, had a history of delays in other Expanded Programs on Immunization (EPI) vaccinations, had parents who did not believe vaccinations were important for their children, and experienced shorter travel times to and longer waiting times in EPI clinics. The children of mothers whose occupational status (technician) were more likely to receive timely MCV1 vaccinations. The timeliness of MCV1 vaccinations should be considered as an additional indicator of the quality of vaccination programs.