https://orcid.org/0000-0001-9780-4109
ABSTRACT
Rotavirus is the most common cause of diarrhea in children worldwide. In 2016, rotavirus infection resulted in 258 173 300 episodes of diarrhea and 128 500 child deaths in the globe. The study aimed to assess the magnitude of Rotavirus vaccine dose-two dropout and associated factors among children who received rotavirus vaccine dose-one in sub-Saharan African countries. The appended and most recent demographic and health survey (DHS) dataset of 17 sub-Saharan African countries was used for data analysis. A total of 73,396 weighted samples were used. Factors associated with the outcome variable were considered significant if their p-values were ≤ .05 in the multilevel mixed-effect logistic regression model. The overall Rotavirus vaccine dose-two dropouts was 10.77% (95% CI 10.55%, 11.00%), which ranged from 2.77% in Rwanda to 37.67% in Uganda. Being younger, late birth order, having difficulty accessing health facilities, having no media exposure, having no work, having home delivery, having no antenatal follow-up, and having no postnatal checkup were factors significantly associated with the outcome variable. The overall Rotavirus vaccine dose-two dropout was higher in sub-Saharan African countries which implies that vaccine dropout is still a great issue in the region. Special attention should be given to those mothers who are young, who have no work, who give birth at home, who experienced difficulty in accessing health facilities, and late birth orders. Furthermore, targeted interventions should be considered for improving access and utilization of media, antenatal care, and postnatal care services.
Introduction
Diarrhea is a major public health problem and the second leading cause of mortality in children.Citation1 Based on recent evidence, 2 billion diarrheal diseases and 1.9 million deaths were reported among children under the age of five years every year globally.Citation2 Rotavirus is the most common cause of diarrhea in children worldwide.Citation3,Citation4 If rotavirus-induced diarrhea is left untreated can result in severe watery diarrhea, vomiting, fever, severe dehydration, and hospitalization.Citation5,Citation6 In 2016, rotavirus infection resulted in 258 173 300 episodes of diarrhea and 128 500 deaths around the globe.Citation7 The majority (90%) of hospitalizations and deaths caused by rotavirus in young children occur in low-income nations in Asia and Africa, particularly in the sub-Saharan region. Low-income or marginalized communities, as well as areas with limited access to safe water, sanitation, and health care, are excessively affected by diarrheal diseases.Citation8
One of the most efficient public health initiatives to lower childhood morbidity and mortality is childhood vaccination.Citation9 More than 28,000 deaths among children are thought to have been prevented by vaccination, especially in sub-Saharan Africa, about 20% of all deaths related to diarrhea can be prevented.Citation7 Good personal hygiene like cleanliness and hand washing are important but are not sufficient to prevent the spread of the rotavirus disease. The Rotavirus vaccine is the best way to protect children from rotavirus infection which attributes 9 out of 10 children protection against rotavirus disease.Citation6 WHO reaffirms that the use of rotavirus vaccines should be a part of a comprehensive strategy to control diarrheal diseases, along with increased use of treatment packages (which include zinc and ORS) and prevention measures (such as encouraging early and exclusive breastfeeding, handwashing with soap, and improved water and sanitation).Citation10
The rate difference between the first and last vaccination is known as the vaccination dropout.Citation11 The findings of the prior studies revealed that the prevalence of rotavirus vaccine dose dose-two out of rotavirus vaccine dose dose-one was 1.9% to 6% in Ethiopia,Citation12,Citation13 and 11.7% to 17.1%in Kenya,Citation14 Previous studies revealed that distance from health institution,Citation12,Citation15–21 antenatal care,Citation15–17,Citation19,Citation22,Citation23 place of delivery,Citation15,Citation22,Citation24,Citation25 postnatal care,Citation9,Citation11,Citation12 respondents working status,Citation17 birth orderCitation23 and tetanus toxoid vaccination statusCitation11 were factors significantly associated with Rotavirus vaccine dose-two dropout.
Even though, complete immunization with the rotavirus vaccine prevents rotavirus-induced diarrheal disease and deaths, vaccine dropout is still a great concern in sub-Saharan African countries. Thus, this study aimed to assess the magnitude of Rotavirus vaccine dose two dropout and associated factors among children who received rotavirus vaccine dose one in sub-Saharan African countries using the recent DHS. This could help the concerned bodies to take appropriate measures at the country and regional levels.
Methods
Data source, study setting, period, and design
The study used the recent and appended demographic and health survey dataset from 21 sub-Saharan African countries conducted from 2015 to 2022. DHS is a community-based cross-sectional study conducted every five years to examine health and health-related indicators.
Study population, sampling technique, and analysis
The most recent (from 2015 to 2022) data set of 17 sub-Saharan African countries (Ethiopia, Angola, Burundi, Cameron, Kenya, Senegal, Gambia, Malawi, Liberia, Mali, Sera Leone, Rwanda, Zimbabwe, South Africa, Tanzania, Uganda, and Zambia) was downloaded from the Demographic Health Survey (DHS) program website and appended to have a single data set. Data availability and having recent DHS data (2015 to 2022) were the selection criteria of the study. The cleaned and recorded data were analyzed using STATA (version 14) statistical software. Missing data for the outcome variable were dropped. The weighting sample (v005/1000000) was applied to address under or over-sampling. Variance inflation factor (VIF) was tested to check multi-collinearity between variables with a mean VIF value of 2.56. To determine factors associated with the outcome variable multi-level mixed-effect logistic regression was applied. Four models model I, model II, model III, and model IV, were used to assess the variability of Rota vaccine dropout across the cluster, the association of individual-level variables with the outcome variable, the association of community-level variables with the outcome variable, and association of both individual and community variables with outcome variable respectively. Variables with a p-value of < .025, were candidates for the multivariable analysis in univariate analysis at 95% confidence intervals and variables with a p-value of ≤ .05 were considered as significantly associated with the outcome variable in the final analysis. The weighted total sample participants for the study were 73,396 ().
Table 1. Sample size for rotavirus vaccine dose-two dropouts in the Sub-Saharan African countries.
Study variables
Dependent variable
The outcome variable of this study was the Rotavirus vaccine (Rotarix) dose-two dropouts, in which the child received Rotavirus vaccine dose one but not Rotavirus vaccine dose two. The RV2 dropout was calculated by the number of children who received Rotavirus vaccine dose-one minus the number of children who received Rotavirus vaccine dose-two divided by the number of children who received Rotavirus vaccine dose-one multiplied by 100% from the Kids Record (KR) data set; (Rotavirus vaccine dose-one – Rotavirus vaccine dose-two)/Rotavirus vaccine dose-one × 100%.
Independent variables
The independent variables of this study were individual level (maternal age, maternal education, birth order, household wealth, maternal working status, distance from health institution, husband educational level, place of delivery, media exposure, ANC follow-up, PNC checkup, maternal tetanus toxoid injection before birth, child gender), and community level (residence, community media exposure, community ANC utilization, community literacy level, and community poverty level) variables
Result
Sociodemographic characteristics
A total of weighted samples of 73,396 participants were used for the study. Two-thirds of 49,133 (66.94%) of the participants were rural dwellers. More than Two-thirds 49,317 (67.19%) of the study participants had media exposure. More than two-thirds 50,670 (69.04%) of the respondents were married. Nearly two-thirds 42,688 (62.61%) of the participants didn’t experience difficulty in accessing the health facility. The majority 62,943 (94.39%) of the participants had ANC follow-up ().
Table 2. Sociodemographic characteristics.
Prevalence of rotavirus vaccine dose-two dropouts among children who received rotavirus vaccine dose-one in Sub-Saharan African countries
The overall RV2 dropout among children who received rotavirus vaccine dose-one in Sub-Saharan African countries was 10.77% (95% CI 10.55%, 11.00%). It ranged from 2.77% in Rwanda to 37.67% in Uganda ().
Figure 1. Rotavirus vaccine dose-two dropouts among children who received rotavirus vaccine dose-one in Sub-Saharan African countries.
Model fitness and random effect analysis
There was about 10.83% variability in RV2 dropout due to the difference between communities/clusters as the ICC value showed. The final model (model III), attributed approximately 39.78% of the variation in the likelihood of RV2 dropout to both individual and community-level variables. The lowest deviance, which was 33,730.16 in model III revealed that model III was the best fit for the data ()
Table 3. Model comparison and random effect analysis for rotavirus vaccine dose-two dropout in the Sub-Saharan African countries.
Factors associated with rotavirus vaccine dose-two dropouts in the Sub-Saharan African countries
From the overall variables, in the final fitted model of multivariable logistic regression, being a younger mother, having no media exposure, late birth order, having home delivery, having no PNC checkup, having no ANC follow-up, difficulty in accessing health facility, and had no work were factors significantly associated with the outcome variable ().
Table 4. Multivariable multilevel logistic regression analysis of individual-level and community-level factors associated with rotavirus vaccine dose-two dropouts in the Sub-Saharan African countries.
The odds of RV2 dropout were 1.23 (AOR = 1.23, 95%CI: 1.11, 1.36), 1.18 (AOR = 1.18, 95%CI: 1.06, 1.31), and 1.30 (AOR = 1.30, 95%CI: 1.18, 1.44) times higher among second, third, and fourth birth order respectively as compared with first birth order. The likelihood of RV2 dropout was 1.08 (AOR = 1.08, 95%CI: 1.02, 1.15) times higher among mothers who experienced difficulty in accessing health facilities as compared to their counterparts. Rotavirus vaccine dose-two dropouts were 1.08 (AOR = 1.08, 95%CI: 1.01, 1.16) times higher among mothers who had no media exposure as compared to those mothers who had media exposure. The odds of RV2 dropout was 1.23 (AOR = 1.23, 95%CI: 1.16, 1.31) times higher among mother who had worked as compared with their counterparts. The odds of RV2 dropout was 1.43 (AOR = 1.43, 95%CI: 1.32, 1.54) times higher among mothers who give birth at home compared with mothers who give birth at a health institution. Rotavirus vaccine dose-two dropouts were 1.38 (AOR = 1.38, 95%CI: 1.23, 1.54) times higher among mothers who had no ANC follow-up as compared with mothers who had ANC follow-up. The odds of RV2 dropout was 1.25 (AOR = 1.25, 95%CI: 1.17, 1.33) times higher among mothers who had no PNC checkup as compared with mothers who had PNC checkup.
Discussion
This study aimed to assess Rotavirus vaccine dropout and associated factors among children who received the first dose in sub-Saharan African countries. The overall Rotavirus vaccine dose-two dropouts among children who received rotavirus vaccine dose-one in Sub-Saharan African countries was 10.77% (95% CI 10.55%, 11.00%). It ranged from 2.77% in Rwanda to 37.67% in Uganda. The finding of this study is lower than the prior study conducted in KenyaCitation14 and higher than the study conducted in Ethiopia.Citation12,Citation13 The variation might be because of the difference in sample size, study population, study period, and socioeconomic status. The WHO and UNICEF collaborate to estimate national immunization coverage for various vaccines including RotaC (Second or third dose of rotavirus vaccine, depending on the national schedule).Citation26 By comparing the dropout rates for the Rotavirus vaccine with the WUENIC estimates, we can assess the effectiveness of vaccination programs. High dropout rates, such as the 37.67% in Uganda, indicate challenges in ensuring complete vaccination coverage.
Being a younger mother, having no media exposure, late birth order, having home delivery, having no PNC checkup, having no ANC follow-up, having difficulty accessing health facilities, and having no work were factors associated with Rotavirus vaccine dose-two dropouts. The study at hand revealed that maternal age was associated with Rotavirus vaccine dose-two dropouts. Mothers aged 35 years and above were more likely than mothers aged 15 to 35 to vaccinate rotavirus vaccine dose-two to their children. The findings of this study are in agreement with the previous studies.Citation27–29 It could be because youngers relied on their elder family members’ decisions or approval. Furthermore, it could be because of improvements in maternal and child health care services like ANC follow-up, giving birth at health facilities, and PNC checkups as the maternal age rises.
The odds of Rotavirus vaccine dose-two dropouts were higher among mothers who had no PNC checkup as compared with those who had the PNC checkup. This finding is consistent with the previous studies.Citation9,Citation11,Citation12 It could be because of a lack of access to medical advice from health professionals during the postnatal period. Furthermore, it could be due to the loss of the entry point for child vaccination which is PNC checkup. The odds of Rotavirus vaccine dose-two dropouts were higher among mother who had no ANC follow-up as compared with their counterparts. The finding of this study is supported by the previous studies.Citation15–17,Citation19,Citation22,Citation23 It could be because attending antenatal care may enable them to acquire health and health-related information including complete child immunization from health professionals. As a result, the tendency to vaccinate the child completely increases.
According to the findings of our study, place of delivery is another significant factor for the Rotavirus vaccine dose-two dropouts. The likelihood of Rotavirus vaccine dose-two dropouts was higher among mothers who give birth at home as compared with those mothers who give birth at health institutions. This finding is consistent with earlier studies.Citation15,Citation22,Citation24,Citation25 The possible justification might be that mothers who give birth at home may not have information about immunization schedules.
The characteristics of the children are another predicting factor for the Rotavirus vaccine dose-two dropouts. The likelihood of Rotavirus vaccine dose-two dropouts was higher among late birth orders as compared with the first birth order. This finding is supported by the previous studies.Citation23,Citation30,Citation31 It could be because of the mother’s diminished interest in immunization uptake for late birth orders. Furthermore, it could be as the number of children in the family increases, family resources, including attention and time, are shared among the children which in turn results in vaccine dropout.
The odds of vaccine dropout were higher among mothers who experienced difficulty in accessing health facilities nearby their districts. One of the biggest obstacles to completing a child’s immunizations is the geographical inaccessibility of healthcare facilities in rural areas.Citation32 This finding is consistent with the prior studies.Citation12,Citation15–21 It could be because mothers who didn’t access the health institution nearby their district, may cost their time and money. As a result, they may lost their interest in bringing their child to health institutions for immunization.
Media exposure is another factor associated with the outcome variable of the study. Rotavirus vaccine dose-two dropouts were lower among mothers who had media exposure as compared to those mothers who had no media exposure. The finding of this study is supported by the previous study.Citation15 It could be because mass media has the potential to share messages from the concerned bodies for the target population. Thus, it helps the mother to acquire health-related knowledge including immunization schedules.
The study also revealed that having no work was associated with higher odds of Rotavirus vaccine dose-two dropouts. This is in agreement with the previous study.Citation17 This could be because women who had work exhibit higher levels of financial independence and tend to go to the health facility, which in turn can minimize vaccine dropout.
This study uses nationally representative data from multiple sub-Saharan countries and appropriate statistical analysis which is multilevel analysis. Hence policymakers and the international community can use it as evidence to undertake necessary measures. However, the study has limitations, important factors that could have a big impact on vaccine dropout, like behavior, beliefs, and social norms, are not included in the dataset. Additionally, to measure the vaccine dropout a recall and response bias may have been present.
Conclusion
The overall Rotavirus vaccine dose-two dropout was higher in sub-Saharan African countries which implies that vaccine dropout is still a great issue in sub-Saharan African countries. Being a younger mother, having no media exposure, late birth order, giving birth at home, having no PNC checkup, having no ANC follow-up, having difficulty in accessing health facilities, and having no work were factors significantly associated with the outcome variable. Therefore, special attention should be given to those mothers who are young, who have no work, who give birth at home, who experienced difficulty in accessing health facilities, and late birth orders. Furthermore, targeted interventions should be considered for improving access and utilization of media, antenatal care, and postnatal care service
Author’s contribution
Belayneh Shetie Workneh: involved in designing the study, data extraction, data analysis, interpretation, report writing, and manuscript writing. Enyew Getaneh Mekonen: involved in data curation, and methodology. Alebachew Ferede Zegeye: involved in designing the study, interpretation, analysis, report, and manuscript writing. Almaz Tefera Gonete: involved in software, supervision, and data validation. Tewodros Getaneh Alemu: involved in conceptualization and validation. Tadesse Tarik Tamir: involved in review and editing, validation, and visualization. Berhan Tekeba: involved in conceptualization and methodology. Mulugeta Wassie: involved in software and validation. Alemneh Tadesse Kassie: involved in conceptualization, validation, and writing the original draft. Mohammed Seid Ali: involved in interpretation and manuscript writing.
Availability of data and materials
The datasets generated and/or analyzed during the current study are available in the most recent data of the Demographic and Health Survey and it is publicly available online at (https://www.dhsprogram.com).
Ethical approval and consent to participate
This study was based on an analysis of existing survey datasets in the public domain that are freely available online with all the identifier information anonymized, no ethical approval was required.
Acknowledgments
The authors of the study are grateful to DHS programs for letting us to use the relevant data.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Additional information
Funding
References
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