https://orcid.org/0009-0009-1491-1044
Figures
Abstract
Background
Vitamin A supplementation (VAS) and deworming (DW) are proven, cost-effective interventions that protect children against preventable morbidity, mortality, and the burden of micronutrient deficiencies and parasitic infections. Nevertheless, many children fail to receive both interventions simultaneously, limiting the potential health gains. Assessing co-coverage and its determinants is crucial for guiding integrated child health strategies and closing persistent gaps across Sub-Saharan Africa.
Methods
We analyzed DHS data from 15 Sub-Saharan African countries, including 107,725 children aged 12–59 months. The primary outcome was co-coverage of vitamin A supplementation and deworming within six months. Weighted descriptive statistics and mixed-effects logistic regression assessed determinants at individual, household, community, and country levels, accounting for survey design and clustering. Variables with p < 0.20 or deemed theoretically relevant were included in the multilevel model (p < 0.05, 95% CI).
Results
The pooled co-coverage of vitamin A supplementation (VAS) and deworming (DW) among children aged 12–59 months was 44.0% (95% CI: 43.4–44.6%), despite individual coverage of 57.1% for each intervention. Approximately 13% of children received either Vitamin A or deworming as a single intervention. Nearly 30% of children received neither intervention. Co-coverage was lowest in Sierra Leone (10.3%) and Gabon (13.2%), moderate in Burkina Faso (28.6%), Côte d’Ivoire (31.0%), Mozambique (44.0%), and Tanzania (44.7%), and highest in Lesotho (58.4%) and Rwanda (84.7%). Vitamin A supplementation coverage was lowest in Gabon (15.7%), Sierra Leone (16.5%) and highest in Rwanda (89.1%) and Lesotho (73.6%), while deworming alone was lowest in Sierra Leone (30.3%) and Burkina Faso (36.7%) and highest in Rwanda (89.4%) and Lesotho (62.4%). Co-coverage of vitamin A supplementation and deworming was higher among children aged 24–47 months (AOR = 1.07), fully immunized children (AOR = 1.41), and those with older, educated mothers who attended antenatal care (AORs 1.14–1.59) or had media exposure (AOR = 1.13). Household wealth also increased the likelihood (AORs 1.27–1.64), while urban residence reduced it (AOR = 0.84). At the country level, compared with Burkina Faso, Rwanda (AOR = 20.05), Mauritania (AOR = 4.30), and Lesotho (AOR = 3.92) had the highest odds, whereas Gabon (AOR = 0.36) and Sierra Leone (AOR = 0.22) had the lowest inter-country disparities in integrated child health coverage. The intraclass correlation coefficient (ICC) indicated that approximately 21.6% of the variance in concurrent coverage was attributable to between-country differences.
Conclusion
Co-coverage of vitamin A supplementation and deworming in 15 sub-Saharan Africa countries is low, with only 44% of children aged 12–59 months receiving both interventions, far below the WHO 80% target. Coverage varied widely, with Rwanda leading and Sierra Leone and Gabon lagging. Strengthened harmonized campaigns, routine service integration, and targeted outreach are essential to improve equitable child health outcomes.
Citation: Yewodiaw TK, Bitewa MD, Tareke AA (2026) Concurrent coverage and determinants of vitamin A supplementation and deworming among children aged 12–59 months in 15 Sub-Saharan African countries. PLoS One 21(1): e0339759. https://doi.org/10.1371/journal.pone.0339759
Editor: Susan Horton, University of Waterloo, CANADA
Received: August 31, 2025; Accepted: December 11, 2025; Published: January 15, 2026
Copyright: © 2026 Yewodiaw et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: This study is based on publicly available Demographic and Health Survey (DHS) data. The datasets analyzed are available from the DHS Program website (https://dhsprogram.com/data/ ) upon reasonable request after registration and approval of data access.
Funding: The author(s) received no specific funding for this work.
Competing interests: No competing interest.
Introduction
Vitamin A deficiency (VAD) and soil-transmitted helminths (STH) remain co-endemic among children aged 12–59 months in Sub-Saharan Africa (SSA), causing morbidity, mortality, and the burden of micronutrient deficiencies and parasitic infections [1,2]. The World Health Organization (WHO) recommends giving vitamin A twice a year, together with yearly deworming (DW). Doing both at the same time rather than separately helps boost children’s immunity, reduce parasite infections, and make programs more efficient [3–5]. VAD and infections caused by STH remain major global health problems, affecting approximately 190 million and 1.5 billion children worldwide, respectively [2,6]. In Sub-Saharan Africa (SSA), vitamin A deficiency remains a major public health concern, affecting approximately one-third to nearly half of preschool-aged children. Similarly, STH infections, particularly Ascaris lumbricoides, are highly prevalent [7,8], with an estimated 28–30% of children infected. These conditions contribute substantially to adverse health outcomes, including anemia, impaired immunity, and growth retardation [9]. Despite longstanding policies, coverage remains heterogeneous within SSA countries, with gaps driven by socioeconomic inequities, geographic access, variable campaign performance, and service fragmentation [10–12]. Concurrently delivering vitamin A and deworming via Child Health Days or EPI touchpoints boosts coverage and cuts costs, but success hinges on coordination, supply reliability, and community engagement [4,7,10]. Looking at the proportion of children who receive both vitamin A supplementation and deworming on schedule gives a clearer picture of how well programs are working and highlights gaps in integrated delivery [11–13]. Co-coverage determinants operate across levels: child age, maternal (age, education, media exposure, employment), household wealth, and community factors (rurality, region, outreach intensity, facility access [11–14]. The DHS offers standardized, nationally representative data that let us track how many children receive both interventions and explore the factors behind it across countries. This helps identify gaps in equity and guide policies for more effective integrated delivery [13,15]. Accordingly, this study combines recent DHS data from sub-Saharan Africa to measure how many children aged 12–59 months receive both VAS and DW, and to identify individual, household, and community factors that can help improve integrated child health programs.
Methods
Study design and data sources
We used data from the most recent DHS conducted between 2019 and 2024 in 15 sub-Saharan Africa (SSA) countries. The DHS employs a stratified two-stage cluster sampling design that yields nationally representative data on women, children, and households. The analysis focused on 107,725 children aged 12–59 months living with their mothers at the time of the survey. Although VAS is recommended beginning at 6 months of age, DW is administered starting at 12 months; therefore, children younger than 12 months were excluded to ensure comparability of co-coverage for both interventions. For this analysis, we drew on the Kids Recode files, which provide information on children under five years of age and their mothers. We restricted the sample to children aged 12–59 months, as this age group is eligible for both VAS and DW interventions according to WHO guidelines. Delivery Platform Profiles: To contextualize VAS and DW co-coverage, we collected information on each country’s delivery platform during the DHS survey year, drawing from UNICEF program reports, Ministry of Health guidelines, and published literature. Delivery mechanisms were categorized as routine facility-based delivery, campaign-based delivery (e.g., biannual Child Health Days), or mixed platforms combining routine services with community outreach or periodic campaigns [16–21]. These profiles were compiled into a Supplementary Table (Table 2) and used to interpret cross-country differences in co-coverage. For example, Mozambique and Kenya primarily used routine delivery with active community health worker outreach, while Tanzania relied on biannual Child Health Days with limited routine VAS. Incorporating delivery platform data allowed us to better understand structural drivers of low, moderate, and high co-coverage patterns.
Study population.
The analytic sample consisted of 107,725, 12–59-month-old children who had valid information on VAS and DW in the six months preceding the survey. Children with missing or “don’t know” responses were excluded from the analysis. Pooling across countries provided adequate statistical power to assess both individual- and community-level determinants while capturing cross-country variations.
Outcome variable.
The primary outcome was co-coverage, defined as receipt of both VAS and DW within the six months preceding the survey, based on maternal recall and verified with child health cards when available. Children who received both interventions were classified as having concurrent coverage. VAS and DW captured by DHS variables, each recoded as binary (1 = received, 0 = not received). A composite variable was created: 0 = neither VAS nor DW received, 1 = received either VAS or DW only, and 2 = received both (full co-coverage). For regression, the outcome was further binary (1 = co-coverage, 0 = not co-coverage) [22,23].
Independent variables.
We examined factors influencing co-coverage at three interconnected levels: individual, household, and community. At the individual level, we considered the child’s age, sex, birth order, immunization status, and maternal characteristics, including age, education, employment status, antenatal care (ANC) visits, and exposure to media [3,24–34]. At the household level, we assessed the family’s wealth index, household size, and place of residence (urban or rural) [35,36]. At the community level, we aggregated data on maternal education, household wealth, and media exposure within each cluster, categorizing them as “low” or “high” based on national medians. This approach aligns with methodologies used in previous research to understand community-level influences on child health [33,37].
Statistical analysis
All analyses accounted for the complex survey design by applying DHS sampling weights, primary sampling units, and strata using the svy commands in Stata. In bringing together data from the 15 countries, we wanted to look at the results from two different angles. The first was by using population-proportionate weights, which keep each country’s share of the data in line with its actual population size. This way, larger countries naturally contribute more to the overall estimate, making the pooled result closer to the true picture of the whole region. The second approach was to use equal-country weights, where every country counts the same, no matter its population. This method gives smaller countries an equal voice in the analysis, making comparisons across countries fairer and not dominated by the bigger ones. Similar strategies have been used in past multi-country DHS studies to balance representativeness with comparability. Descriptive statistics were used to summarize background characteristics and the coverage of VAS, DW, and their co-coverage. Bivariate associations were tested using chi-square statistics.
To examine determinants of co-coverage, we fitted multilevel mixed-effects logistic regression models (melogit in Stata), recognizing the hierarchical nature of the data (children nested within clusters, and clusters nested within countries). The fixed effects estimated associations between predictors and co-coverage, while random effects captured between-cluster and between-country variability. Adjusted odds ratios (AOR) with 95% confidence intervals (CI) were reported. Model fit was assessed using the intraclass coefficient (ICC), Akaike information criterion (AIC), and Bayesian Information Criterion (BIC).
Ethical considerations
This study is a secondary analysis of publicly available data from the most recent DHS conducted between 2019 and 2024 across multiple Sub-Saharan Africa (SSA) countries. The original DHS surveys obtained ethical approval from the ICF Institutional Review Board and the respective national ethics committees of each participating country. Written informed consent was obtained from all respondents during the survey interviews. The datasets contain no personal identifiers, thereby ensuring participant confidentiality. Access to the data was granted by the DHS Program under their standard data use agreement (https://dhsprogram.com).
Results
Characteristics of the study population
The analysis included 107,725 children aged 12–59 months, with a fairly even distribution across age groups: 27,687 (25.7%) were 12–23 months, 26,120 (24.5%) were 24–35 months, 27,409 (25.4%) were 36–47 months, and 26,509 (24.3%) were 48–59 months. Slightly more children were female (54,473; 50.4%) than male (53,252; 49.6%). About two-thirds of children were second-born or higher: 39,996 (38.5%) were second- or third-born, and 42,326 (35.5%) were fourth-born or higher.
Most mothers were aged 25–34 years (50,746; 47.4%), with 27,199 (24.9%) aged 15–24 years and 29,780 (27.8%) aged 35–49 years. Regarding maternal education, 41,277 (29.5%) had no formal education, 34,366 (33.9%) had primary education, 27,462 (30.1%) had secondary education or higher, and 4,620 (6.5%) had tertiary education. Children were from households across all wealth levels: 30,350 (22.9%) in the poorest quintile and 14,612 (18.0%) in the richest quintile. Most children lived in rural areas (70,904; 59.6%) compared to urban areas (36,821; 40.4%). The sample spanned 15 Sub-Saharan countries, with Kenya (14,679; 18.2%), Mauritania (8,569; 12.8%), Madagascar (9,071; 7.0%), Tanzania (7,998; 6.8%), and Ghana (7,052; 6.6%) contributing the largest shares. Other countries each accounted for smaller proportions ranging from 3.0% to 6.0% of the sample (Table 1).
Comparative coverage of Vitamin A supplementation, deworming, and co-coverage of 15 sub-Saharan Africa countries
Overall, pooled concurrent coverage of VAS and DW among 107,725 children aged 12–59 months was 44.0% (47,599 children; 95% CI: 43.4–44.6). Individually, 57.1% of children (61,503; 95% CI: 56.4–57.7) received vitamin A, and the same proportion received deworming (61,503; 95% CI: 56.5–57.7). Notably, 13.1% of children (14,106) received only one of the interventions, while 55.9% (60,126 children; 95% CI: 55.4–56.6) received either one or neither, highlighting substantial gaps in integrated service delivery and missed opportunities for maximizing child health benefits.
Co-coverage of both interventions, which means the proportion of children who received vitamin A and deworming concurrently, was highest in Rwanda (84.7%), followed by Lesotho (58.4%), Senegal (56.6%), and Mauritania (54.5%). In contrast, the lowest co-coverage was reported in Sierra Leone (10.3%) and Gabon (13.2%), reflecting differences delivery of the two interventions. Countries such as Mozambique (44%), Tanzania (44.7%), and Kenya (49.5%) showed moderate co-coverage, while Ghana, despite its high vitamin A coverage, showed lower co-coverage (37.7%) due to modest deworming uptake.
The coverage of VAS and DW among children aged 12–59 months varied widely across the 15 Sub-Saharan Africa countries. VAS ranged from as low as 15.7% in Gabon and 16.5% in Sierra Leone to as high as 89.1% in Rwanda. Other countries with relatively high VAS coverage included Ghana (74.3%), Lesotho (73.6%), and Senegal (68.4%). In contrast, Burkina Faso (41.5%), Madagascar (39.2%), and Côte d’Ivoire (46.1%) revealed moderate uptake.
DW coverage showed a similar heterogeneity, with the highest levels observed in Rwanda (89.4%), Gabon (67.9%), and Senegal (69.2%). Conversely, the lowest coverage was documented in Sierra Leone (30.3%), Burkina Faso (36.7%), and Côte d’Ivoire (46.9%). Some countries, such as Ghana (44.6%) and Mozambique (47.5%), recorded moderate uptake despite having relatively strong VAS. These findings show substantial cross-country variation, with some countries achieving strong and balanced delivery of both interventions (Rwanda, Senegal, and Lesotho), while others show programmatic gaps where one intervention far outpaces the other (Gabon with deworming, Ghana with vitamin A) (Fig 1).
Co-coverage of vitamin A supplementation and deworming delivery platforms by Country
Co-coverage of VAS and DW varies widely across the 15 countries, reflecting differences in delivery platforms and program coordination. Rwanda achieved the highest co-coverage (84.7%), followed by Lesotho (58.4%) and Tanzania (44.7%), illustrating the effectiveness of well-coordinated campaigns combined with routine delivery. Countries with mixed platforms, such as Kenya, Senegal, Mozambique, Ghana, and The Gambia, attained moderate co-coverage (37–56%), where routine and campaign approaches improved access, but inconsistencies in timing or targeting limited simultaneous uptake. Conversely, Sierra Leone, Gabon, Burkina Faso, Côte d’Ivoire, and Madagascar exhibited low co-coverage (10–31%) due to fragmented, poorly documented, or unsynchronized delivery systems. These findings underscore that high individual coverage of either intervention does not automatically translate into high co-coverage; achieving optimal simultaneous uptake requires careful integration, timing coordination, and alignment of delivery platforms (Table 2) [18,20,21,38–44].
Determinants of vitamin A supplementation and deworming, and co-coverage in sub-Saharan Africa countries
Compared with children aged 12–23 months, those aged 24–35 months (AOR = 1.07; 95% CI: 1.03–1.12) and 36–47 months (AOR = 1.07; 95% CI: 1.02–1.13) had significantly higher odds, while children aged 48–59 months were less likely to be covered (AOR = 0.92; 95% CI: 0.88–0.97). Child’s sex and birth order showed no consistent associations.
Children of mothers aged 25–34 (AOR = 1.14; 95% CI: 1.09–1.19) and 35–49 (AOR = 1.25; 95% CI: 1.18–1.33) were more likely to receive the intervention compared to younger mothers (15–24 years). Education showed a clear gradient: primary (AOR = 1.18; 95% CI: 1.13–1.23), secondary (AOR = 1.34; 95% CI: 1.27–1.40), and higher (AOR = 1.48; 95% CI: 1.36–1.62) all increased odds compared with no schooling.
Compared with the poorest households, children in poorer (AOR = 1.14; 95% CI: 1.08–1.20), middle (AOR = 1.27; 95% CI: 1.20–1.34), richer (AOR = 1.42; 95% CI: 1.33–1.52), and richest (AOR = 1.64; 95% CI: 1.51–1.78) households had progressively higher odds. Media exposure was also significant (AOR = 1.13; 95% CI: 1.07–1.19).
Fully immunized children were more likely to receive co-coverage (AOR = 1.41; 95% CI: 1.35–1.48). Antenatal care visits also mattered to mothers with 1–3 visits (AOR = 1.50; 95% CI: 1.34–1.68) and 4 + visits (AOR = 1.59; 95% CI: 1.43–1.77) had greater odds than those with no ANC.
Children from medium (AOR = 1.26; 95% CI: 1.17–1.36) and high (AOR = 1.33; 95% CI: 1.21–1.47) cluster wealth areas were more likely to be covered. Higher cluster education was also beneficial, with medium (AOR = 1.22; 95% CI: 1.14–1.30) and high (AOR = 1.29; 95% CI: 1.19–1.40) levels increasing odds compared with low-education clusters. Urban residence was associated with reduced odds (AOR = 0.84; 95% CI: 0.78–0.91).
Finally, relative to Burkina Faso, countries such as Côte d’Ivoire (AOR = 1.37), Gambia (AOR = 2.02), Kenya (AOR = 2.53), Lesotho (AOR = 3.92), Mauritania (AOR = 4.30), Mozambique (AOR = 2.20), Rwanda (AOR = 20.05), Senegal (AOR = 4.70), Tanzania (AOR = 2.13), and Liberia (AOR = 2.16) had significantly higher odds of co-coverage. In contrast, Gabon (AOR = 0.36) and Sierra Leone (AOR = 0.22) had markedly lower odds. Stepwise inclusion of individual, community, and country-level factors reduced clustering from ICC 37.3% (MOR 3.79) in the null model to 21.6% (MOR 2.48) in the full model, explaining 53.7% of the between-cluster variance (PCV). The final model showing the best fit (lowest AIC/BIC) (Table 3).
Discussion
Pooled concurrent coverage of vitamin A supplementation and deworming among children in 15 sub-Saharan Africa countries
In this study, only 44.0% of children aged 12–59 months received VAS and DW concurrently, highlighting a substantial gap in co-coverage despite relatively high individual intervention rates. This gap indicates missed opportunities for integrated service delivery, which is essential to maximize child health benefits and program efficiency [32,45]. Ensuring co-coverage is particularly important because concurrent delivery can have synergistic effects on nutritional status, immunity, and growth outcomes [27,32]. Individual coverage of VAS and DW was higher, at 57.1% for each intervention, suggesting that delivery platforms successfully reach a majority of children with at least one service [45]. However, the difference between individual coverage and co-coverage underscores the limitations of current delivery strategies in achieving synchronized uptake [27,32,45]. Evidence from several countries highlights the advantages of integrating VAS with DW. Studies from Bangladesh and Indonesia show that children who received both β-carotene (a precursor of vitamin A) and deworming experienced greater improvements in serum retinol and growth outcomes than those who received either intervention alone [45–47]. Similarly, research from Zaire reported that VAS improved growth among vitamin A-deficient children, whereas deworming alone offered minimal benefits [46,47]. These findings support the potential of combined interventions to enhance child health [27,32,46,47]. Yet, the evidence is not entirely consistent. Systematic reviews and meta-analyses, including Cochrane reviews, indicate that deworming alone often yields variable effects on growth, cognition, and nutritional outcomes [48,49]. In Uttar Pradesh, India, twice-yearly deworming among lightly infected children did not significantly improve weight gain or reduce mortality [27]. Some studies suggest that gains in growth and survival are largely driven by VAS rather than deworming, particularly in areas with low infection intensity [46–48]. These mixed results may explain the persistently low co-coverage, highlighting that the impact of integrated delivery depends on context-specific factors such as nutritional status, infection burden, and intervention timing [48,50]. Targeting combined delivery to high-impact settings is key to maximizing child health benefits.
Programmatically, co-delivery of vitamin A and deworming is safe and feasible, with no adverse interactions reported between vitamin A and albendazole [51]. Yet, operational challenges often limit coverage. In Siaya Country, Kenya, VAS reached over 80% of children, while deworming reached only 50% [52]. Similarly, in South Africa, many children missed both interventions despite high vaccination coverage [53]. Supply chain issues, differing campaign schedules, and workforce constraints are likely key contributors to these gaps [52,53].
Overall, VAS and DW are widely recognized as safe, essential, and compatible interventions [27,45,52]. They can offer added benefits, particularly in areas where vitamin A deficiency and helminth infections overlap [27,46–48]. Yet, evidence shows that deworming alone often has a limited impact, and the success of combined delivery can vary depending on context [45,48]. Efforts to improve co-coverage should focus on integrated planning, coordinated delivery, and targeted outreach to high-risk populations, taking local epidemiology and health system capacity into account [32,50,51].
Comparative analysis of co-coverage of vitamin A supplementation and deworming across sub-Saharan Africa countries
High co-coverage countries, including Rwanda (84.7%), Lesotho (58.4%), Senegal (56.6%), and Mauritania (54.5%), demonstrate successful integration of VAS and DW programs. Rwanda stands out with VAS and DW coverage above 89%, reflecting strong health systems, well-trained community health workers, and coordinated campaigns. Lesotho and Senegal have also achieved co-coverage above 50% through national coordination and effective community engagement [50,53]. These findings align with global evidence that well-planned, integrated campaigns enhance simultaneous uptake, maximize health benefits, and improve cost-effectiveness [50,54]. These countries could achieve Sub-Saharan Africa (SSA) substantial co-coverage through campaign-based approaches, such as biannual Child Health Days, allowing simultaneous provision of VAS and DW with strong partner coordination [55,56].
Moderate co-coverage countries, such as Mozambique (44.0%), Tanzania (44.7%), Kenya (49.5%), and Ghana (37.7%), show partial success. In Mozambique, VAS and deworming reach children through routine, outreach, and occasional campaigns, but poor coordination means many children miss receiving both. Kenya demonstrates better synchronization, while Tanzania shows high VAS but lower deworming coverage. These patterns reflect partial integration, often caused by staggered campaign schedules, workforce limitations, and regional inequities [34,51,52]. This pattern aligns with evidence that partial integration usually occurs when one intervention reaches children effectively while the other lags behind [48,51]. Programmatic strategies such as synchronized delivery, stronger community engagement, and better resource allocation have been shown to improve co-coverage in such contexts [34]. Moderate co-coverage highlights room for improvement, with operational gaps in synchronized campaigns, monitoring, and community outreach [48,51]. Those countries rely on routine facility-based delivery supplemented by community health worker outreach, which provides continuous access but is constrained by supply-chain challenges and inconsistent campaign alignment [17,55].
Low co-coverage countries, including Sierra Leone (10.3%) and Gabon (13.2%), highlight persistent delivery challenges. In Gabon, VAS coverage was only 15.7% despite 67.9% deworming coverage, while Sierra Leone had moderate deworming (30.3%) but very low VAS uptake (16.5%. These low rates are consistent with studies identifying logistical constraints, unsynchronized campaigns, weak community mobilization, and supply chain interruptions as major barriers [27,45,48]. Systematic planning, aligned campaigns, and strengthened health systems are essential to improve co-coverage [45,48]. Overall, co-coverage varies widely, with high-performing countries benefiting from strong governance and coordinated campaigns, while moderate and low performers face operational and systemic barriers. Targeted strategies focusing on synchronized delivery, high-risk populations, and health system strengthening are critical to maximize child health outcomes across Sub-Saharan Africa [34,45–54]. Low co-coverage countries face systemic barriers, while high performers offer models of effective integration. Strengthening co-coverage will require adopting best practices such as coordinated campaigns, robust supply chains, and active community engagement [53]. Categorizing countries by co-coverage allows targeted strategies to optimize child health outcomes across Sub-Saharan Africa. Low-coverage countries often have fragmented delivery systems, with VAS and DW delivered separately through vertical programs or irregular campaigns, resulting in poor simultaneous uptake [52,56]. Differences in co-coverage were closely aligned with the underlying delivery platforms. Countries relying predominantly on campaign-based delivery, such as Tanzania, often achieved higher peak coverage but showed variability between rounds. In contrast, settings where routine delivery with community outreach is the primary platform (Mozambique, Kenya) demonstrated more stable but moderate coverage, often constrained by health worker shortages and geographic access challenges. These platform differences highlight that co-coverage performance cannot be interpreted solely from DHS data without considering operational delivery models.
Determinants of integrated vitamin A supplementation and deworming coverage in children
Child age showed a mixed pattern: children between 24–47 months were more likely to receive both interventions, while those aged 48–59 months were less likely. This suggests that coverage is higher in early childhood but declines as children grow older, likely due to fewer contact opportunities with health services. Similar trends have been noted in programmatic evaluations of Child Health Days and routine service platforms [3,30]. Maternal age showed a clear positive gradient, with older mothers more likely to ensure their children received both interventions. Similar findings have been reported elsewhere, linking maternal maturity with better care-seeking behaviors and greater ability to navigate health services [28,29]. Maternal education was also one of the strongest predictors, showing a dose–response effect from primary through higher education. This aligns with extensive evidence that maternal literacy improves uptake of immunization, supplementation, and other preventive child health practices [22,26]. Household wealth showed a clear gradient, with children from the richest households nearly twice as likely to receive both interventions compared to those from the poorest. This reflects the persistent pro-rich inequalities seen in the use of preventive child health services across Sub-Saharan Africa [31,57]. Media exposure also played an important role, as mothers with access to radio or television were more likely to ensure their children received both interventions. This supports earlier evidence that information exposure through mass media improves maternal health service use and uptake of child health interventions [24,33]. Children who were fully immunized had substantially higher odds of co-coverage, underlining the importance of integrated service delivery platforms such as routine immunization and campaign contacts [57,58]. Antenatal care (ANC) utilization proved to be a strong predictor of co-coverage. Mothers who attended 1–3 visits, and particularly those with four or more, were more likely to have their children receive both interventions. This aligns with the continuum of care framework, which emphasizes how maternal engagement with health services directly supports the uptake of preventive child health interventions [25,28,29]. Community wealth and education were positively associated with co-coverage, even after adjusting for individual factors, though the effect was reduced in the full model. In contrast, community-level media exposure was not significant once household media access was accounted for, highlighting the stronger influence of direct information exposure on child health service uptake [31,35]. Unexpectedly, children living in urban areas were less likely to receive both interventions. This contrasts with the usual urban advantage. In many countries, this pattern aligns with existing evidence showing that rural outreach campaigns and Child Health Days often target hard-to-reach communities, resulting in relatively higher coverage in rural areas. More consistent community health worker (CHW) outreach in rural settings, congestion within urban health systems, and variability in the reach of campaign-based platforms may also contribute to these differences [30]. This study’s main strengths are the use of large, nationally representative DHS data from 15 Sub-Saharan Africa countries and the focus on concurrent coverage of VAS and DW, which provides multi-country insights into overlapping child health interventions. The cross-sectional design limits causal inference, and supplementation and DW data relied on maternal recall, partially mitigated by verification with health cards. DHS surveys do not capture supply-chain conditions; while VAS capsules are generally well supplied through global programs, DW tablets are often scarce, and unmeasured stock-outs may have influenced DW and co-coverage estimates. Additionally, programmatic variables such as campaign timing and input availability were not captured, limiting the assessment of operational factors affecting coverage.
Conclusions
Less than half of children aged 12–59 months in Sub-Saharan Africa receive both vitamin A supplementation and deworming, well below the WHO-recommended 80% target, despite higher individual coverage. High-performing countries, such as Rwanda and Lesotho, have exceeded targets through coordinated campaigns, while moderate and low-coverage countries, including Mozambique, Sierra Leone, and Gabon, face operational and systemic barriers. Uptake is strongly influenced by maternal age, education, household wealth, antenatal care attendance, and child immunization. Low-coverage countries require strengthened routine delivery and reliable deworming supply chains; moderate-coverage settings need improved supervision, microplanning, and community–facility linkages; and high-coverage countries demonstrate the effectiveness of synchronized platforms. Enhancing coordination, supply chains, and integration with routine services can improve efficiency, equity, and child health outcomes across the region.
References
- 1.
Organization WH. Global prevalence of vitamin A deficiency in populations at risk 1995-2005: WHO global database on vitamin A deficiency; 2009.
- 2. Pullan RL, Brooker SJ. The global limits and population at risk of soil-transmitted helminth infections in 2010. Parasit Vectors. 2012;5:81. pmid:22537799
- 3.
Guideline W. Vitamin A supplementation in infants and children 6–59 months of age, vol. 269. Geneva: World Health Organization; 2011. 16 p.
- 4.
Organization WH. Guideline: preventive chemotherapy to control soil-transmitted helminth infections in at-risk population groups; 2017.
- 5. Imdad A, Mayo-Wilson E, Haykal MR, Regan A, Sidhu J, Smith A, et al. Vitamin A supplementation for preventing morbidity and mortality in children from six months to five years of age. Cochrane Database Syst Rev. 2022;3(3):CD008524. pmid:35294044
- 6. Stevens GA, Bennett JE, Hennocq Q, Lu Y, De-Regil LM, Rogers L, et al. Trends and mortality effects of vitamin A deficiency in children in 138 low-income and middle-income countries between 1991 and 2013: a pooled analysis of population-based surveys. Lancet Glob Health. 2015;3(9):e528-36. pmid:26275329
- 7.
Organization WH. Ending the neglect to attain the sustainable development goals: a road map for neglected tropical diseases 2021–2030: overview; 2020.
- 8. Ahmed T, Hossain M, Sanin KI. Global burden of maternal and child undernutrition and micronutrient deficiencies. Ann Nutr Metab. 2012;61 Suppl 1:8–17. pmid:23343943
- 9. Gotine AREM, Xavier SP, Vasco MD, Alfane NWA, Victor A. Prevalence and predictors of anemia in children under 5 years of age in sub-Saharan Africa: a systematic review and meta-analysis. medRxiv. 2024:2024.12.18.24319278.
- 10. Palmer AC, Diaz T, Noordam AC, Dalmiya N. Evolution of the child health day strategy for the integrated delivery of child health and nutrition services. Food Nutr Bull. 2013;34(4):412–9. pmid:24605691
- 11.
Croft N, Marshall A, Allen C. Guide to DHS statistics. Rockville (MD): ICF International; 2018. p. 33–2.
- 12. Victora C, Requejo J, Boerma T, Amouzou A, Bhutta ZA, Black RE, et al. Countdown to 2030 for reproductive, maternal, newborn, child, and adolescent health and nutrition. Lancet Glob Health. 2016;4(11):e775–6. pmid:27650656
- 13. Requejo J, Diaz T, Park L, Chou D, Choudhury A, Guthold R, et al. Assessing coverage of interventions for reproductive, maternal, newborn, child, and adolescent health and nutrition. BMJ. 2020;368:l6915. pmid:31983681
- 14. Barros AJD, Ronsmans C, Axelson H, Loaiza E, Bertoldi AD, França GVA, et al. Equity in maternal, newborn, and child health interventions in countdown to 2015: a retrospective review of survey data from 54 countries. Lancet. 2012;379(9822):1225–33. pmid:22464386
- 15.
Demographic I. Health survey sampling and household listing manual. Calverton: Measure DHS; 2012.
- 16. Chimoyi L, Chikovore J, Musenge E, Mabuto T, Chetty-Makkan CM, Munyai R, et al. Understanding factors influencing utilization of HIV prevention and treatment services among patients and providers in a heterogeneous setting: a qualitative study from South Africa. PLOS Glob Public Health. 2022;2(2):e0000132. pmid:36962320
- 17. Ezezika O, Quibrantar S, Okolie A, Ariyo O, Marson A. Barriers and facilitators to the implementation of vitamin A supplementation programs in Africa: a systematic review. Nutr Health. 2025;31(2):383–94. pmid:39584721
- 18. Fauveau V, UNFPA--AMDD Working Group on Indicators. Program note: using UN process indicators to assess needs in emergency obstetric services: Gabon, Guinea-Bissau, and The Gambia. Int J Gynaecol Obstet. 2007;96(3):233–40. pmid:17291505
- 19. Fenta SM, Fenta HM. Individual and community-level determinants of childhood vaccination in Ethiopia. Arch Public Health. 2021;79(1):53. pmid:33879269
- 20.
Hayford D. Acceptability of school-based de-worming exercise for the control of schistosomiasis in the Biakoye District of Ghana. University of Ghana; 2021.
- 21. Horton S, Blum LS, Diouf M, Ndiaye B, Ndoye F, Niang K, et al. Delivering vitamin A supplements to children aged 6-59 months: comparing delivery through campaigns and through routine health services in Senegal. Curr Dev Nutr. 2018;2(4):nzy006. pmid:30019030
- 22. Janmohamed A, Klemm RD, Doledec D. Determinants of successful vitamin A supplementation coverage among children aged 6-59 months in thirteen sub-Saharan African countries. Public Health Nutr. 2017;20(11):2016–22. pmid:28532531
- 23. Janmohamed A, Doledec D, Dissieka R, Jalloh UH, Juneja S, Beye M, et al. Vitamin A supplementation coverage and associated factors for children aged 6 to 59 months in integrated and campaign-based delivery systems in four sub-Saharan African countries. BMC Public Health. 2024;24(1):1189. pmid:38678255
- 24. Aboagye RG, Seidu A-A, Ahinkorah BO, Cadri A, Frimpong JB, Hagan JE, et al. Association between frequency of mass media exposure and maternal health care service utilization among women in sub-Saharan Africa: implications for tailored health communication and education. PLoS One. 2022;17(9):e0275202. pmid:36174071
- 25. Alem AZ, Shitu K, Alamneh TS. Coverage and factors associated with completion of continuum of care for maternal health in sub-Saharan Africa: a multicountry analysis. BMC Pregnancy Childbirth. 2022;22(1):422. pmid:35590260
- 26. Anwar M, Faisal A, Jawed K, Yousuf A, Shaikh I. Association between maternal literacy and child immunization according to the expanded program on immunization schedule in a primary health care center of a squatter settlement in Karachi. Cureus. 2023;15(8).
- 27. Awasthi S, Pande VK, Fletcher RH. Effectiveness and cost-effectiveness of albendazole in improving nutritional status of pre-school children in urban slums. Indian Pediatr. 2000;37(1):19–29. pmid:10745385
- 28. Budu E, Ahinkorah BO, Aboagye RG, Armah-Ansah EK, Seidu A-A, Adu C, et al. Maternal healthcare utilsation and complete childhood vaccination in sub-Saharan Africa: a cross-sectional study of 29 nationally representative surveys. BMJ Open. 2021;11(5):e045992. pmid:33986059
- 29. Budu E, Seidu A-A, Agbaglo E, Armah-Ansah EK, Dickson KS, Hormenu T, et al. Maternal healthcare utilization and full immunization coverage among 12-23 months children in Benin: a cross sectional study using population-based data. Arch Public Health. 2021;79(1):34. pmid:33726859
- 30. Clohossey PC, Katcher HI, Mogonchi GO, Nyagoha N, Isidro MC, Kikechi E, et al. Coverage of vitamin A supplementation and deworming during Malezi Bora in Kenya. J Epidemiol Glob Health. 2014;4(3):169–76. pmid:25107652
- 31. Debie A, Amare G, Handebo S, Mekonnen ME, Tesema GA. Individual- and community-level determinants for complete vaccination among children aged 12-23 months in Ethiopia: a multilevel analysis. Biomed Res Int. 2020;2020:6907395. pmid:33062691
- 32. Dickson R, Awasthi S, Williamson P, Demellweek C, Garner P. Effects of treatment for intestinal helminth infection on growth and cognitive performance in children: systematic review of randomised trials. BMJ. 2000;320(7251):1697–701. pmid:10864543
- 33. Fatema K, Lariscy JT. Mass media exposure and maternal healthcare utilization in South Asia. SSM Popul Health. 2020;11:100614. pmid:32596437
- 34. Gebrekidan AY, Asgedom YS, Woldegeorgis BZ, Kassie GA, Haile KE, Damtew SA, et al. Vitamin A supplementation status and associated factors among children aged 6-59 months in Tanzania: a multi-level analysis. Front Nutr. 2024;11:1422805. pmid:39166133
- 35. Liyew B, Tarekegn GE, Kassew T, Tsegaye N, Asfaw MG, Tilahun AD, et al. Individual and community-level factors of treatment-seeking behaviour among caregivers with febrile children in Ethiopia: a multilevel analysis. PLoS One. 2022;17(3):e0264707. pmid:35298490
- 36. Wallace AS, Ryman TK, Dietz V. Experiences integrating delivery of maternal and child health services with childhood immunization programs: systematic review update. J Infect Dis. 2012;205 Suppl 1:S6-19. pmid:22315388
- 37. Belay DG, Asratie MH, Gashaw M, Tsega NT, Endalew M, Aragaw FM. Community and individual level determinants and spatial distribution of deworming among preschool age children in Ethiopia: spatial and multi-level analysis. BMC Public Health. 2022;22(1):872. pmid:35501790
- 38. Afolabi MO, Sow D, Ndiaye JLA, Greenwood B. Safety and effectiveness of delivering mass drug administration for helminths through the seasonal malaria chemoprevention platform among Senegalese children: study protocol for a randomised controlled trial. Trials. 2022;23(1):627. pmid:35922819
- 39.
Jarju AA. Factors associated with diarrhoea among children less than 5 years old in the Gambia: analysis of the 2019/2020 demographic and health survey. 2023.
- 40.
Kollie KK. Factors hindering or promoting the integration of neglected tropical diseases requiring case management into the Liberian health system. University of Liverpool; 2024.
- 41.
Makhupane T. Evaluating the effectiveness of the rubella vaccination program in Lesotho using measels and rubella case-based surveillance data. South Africa: University of South Africa; 2023.
- 42. Ouédraogo CT, Becquey E, Wilson SE, Prince L, Ouédraogo A, Rouamba N, et al. Factors affecting the validity of coverage survey reports of receipt of vitamin a supplements during child health days in southwestern Burkina Faso. Food Nutr Bull. 2016;37(4):529–43. pmid:27604622
- 43. Shibre G, Zegeye B, Lemma G, Abebe B, Woldeamanuel GG. Socioeconomic, sex and area related inequalities in childhood stunting in Mauritania: Evidence from the Mauritania Multiple Indicator Cluster Surveys (2007–2015). PLoS One. 2021;16(10):e0258461.
- 44. Terefe B, Jembere MM, Assimamaw NT, Chekole B. Deworming coverage and its determinants among 12-59 months old children in East Africa: a population-based study. PLoS One. 2024;19(2):e0297377. pmid:38300907
- 45. Hall A, Hewitt G, Tuffrey V, de Silva N. A review and meta-analysis of the impact of intestinal worms on child growth and nutrition. Matern Child Nutr. 2008;4 Suppl 1(Suppl 1):118–236. pmid:18289159
- 46. West KP, LeClerq SC, Shrestha SR, Wu LS, Pradhan EK, Khatry SK, et al. Effects of vitamin A on growth of vitamin A-deficient children: field studies in Nepal. J Nutr. 1997;127(10):1957–65. pmid:9311951
- 47. West KP Jr, Djunaedi E, Pandji A, Kusdiono, Tarwotjo I, Sommer A. Vitamin A supplementation and growth: a randomized community trial. Am J Clin Nutr. 1988;48(5):1257–64. pmid:3189214
- 48. Taylor-Robinson DC, Maayan N, Soares-Weiser K, Donegan S, Garner P. Deworming drugs for soil-transmitted intestinal worms in children: effects on nutritional indicators, haemoglobin, and school performance. Cochrane Database Syst Rev. 2015;2015(7):CD000371. pmid:26202783
- 49. Jullien S, Sinclair D, Garner P. The impact of mass deworming programmes on schooling and economic development: an appraisal of long-term studies. Int J Epidemiol. 2016;45(6):2140–53. pmid:28161712
- 50. Welch VA, Ghogomu E, Hossain A, Awasthi S, Bhutta Z, Cumberbatch C, et al. Deworming and adjuvant interventions for improving the developmental health and well‐being of children in low‐ and middle‐income countries: a systematic review and network meta‐analysis. Campbell Syst Rev. 2016;12(1):1–383.
- 51. Strunz EC, Suchdev PS, Addiss DG. Soil-transmitted helminthiasis and vitamin A deficiency: two problems, one policy. Trends Parasitol. 2016;32(1):10–8. pmid:26724966
- 52. Ochola S, Lelei A, Korir J, Ombati C, Chebet C, Doledec D, et al. Feasibility of delivering vitamin A supplementation (VAS) and deworming through routine community health services in Siaya County, Kenya: a cross-sectional study. Matern Child Nutr. 2024;20(2):e13626. pmid:38311791
- 53. McLaren S, Steenkamp L. Coverage of vitamin A supplementation, deworming and immunisations: associations with nutritional status among urban children younger than 5 years in Nelson Mandela Bay, Eastern Cape Province, South Africa. S Afr J Child Health. 2022;16(4):220–4.
- 54. Haque R, Ahmed T, Wahed MA, Mondal D, Rahman ASMH, Albert MJ. Low-dose beta-carotene supplementation and deworming improve serum vitamin A and beta-carotene concentrations in preschool children of Bangladesh. J Health Popul Nutr. 2010;28(3):230–7. pmid:20635633
- 55. Wirth JP, Petry N, Tanumihardjo SA, Rogers LM, McLean E, Greig A, et al. Vitamin A supplementation programs and country-level evidence of vitamin a deficiency. Nutrients. 2017;9(3):190. pmid:28245571
- 56. Zembe-Mkabile W. Social protection as a nutrition-sensitive instrument to address malnutrition in sub-Saharan Africa: examining the utility of the UNICEF conceptual model of care for maternal and child nutrition. J Int Comp Soc Policy. 2023;39(3):295–305.
- 57. Xavier SP, Mahoche M, Rondó PH, da Silva AM, Flores-Ortiz R, Victor A. Addressing inequalities in vaccination coverage among children aged 12 to 23 months in ten Sub-Saharan African countries: Insights from DHS and MIS Data (2017-2022). MedRxiv. 2024:2024.12.13.24318976.
- 58. Wallace AS, Ryman TK, Dietz V. Experiences integrating delivery of maternal and child health services with childhood immunization programs: systematic review update. J Infect Dis. 2012;205 Suppl 1:S6-19. pmid:22315388