Investigating predictors and barriers to vaccine uptake in children at Konye Health District, South West region Cameroon

Abstract

Introduction

Global immunization initiatives aim for ≥ 90% national and ≥ 80% district-level vaccine coverage; however, uptake remains low in crisis-affected settings like Konye Health District, where only 31.5% of children are completely vaccinated. This study examined socio-demographic, health service, and contextual determinants of vaccination uptake, highlighting the importance of understanding context-specific barriers in settings affected by sociopolitical instability.

Methods

A community-based cross-sectional mixed-methods study was conducted from March to May 2023 among 412 caregivers of children aged 0–59 months. Quantitative data were collected on sociodemographic characteristics, vaccination status, while qualitative data provided in-depth insights into caregiver experiences and contextual challenges. Four health areas were selected through multistage sampling, with caregivers systematically recruited. Community health workers (CHWs), healthcare providers, and facility leaders were purposively selected for qualitative interviews. Multivariable logistic regression identified independent factors associated with vaccination complete vaccination status. Qualitative data from three focus group discussions were transcribed and analyzed thematically to explain and complement quantitative findings.

Results

From 412 participants, 58% were fully immunized. Vaccination completion was significantly associated with respecting all vaccination appointments (AOR = 20.37, 95% CI: 8.63–48.12), Higher household income (AOR = 3.38, 95% CI: 1.57–7.30) and recognizing vaccine side effects (AOR = 4.54, 95% CI: 2.23–9.25). Qualitative findings explained these patterns by highlighting the role of CHW engagement, reminders, and outreach services, alongside barriers such as long travel distances, transportation difficulties, fear of side effects, and conflict-related disruptions.

Conclusion

Vaccination uptake in the Konye Health District remains low due to a complex interplay of caregiver behaviors, socioeconomic conditions, and health system factors. Addressing these interconnected challenges through strengthened community-based approaches, improved service accessibility, and resilient health system strategies is essential for enhancing immunization coverage in the district.

Supplementary Information

The online version contains supplementary material available at https://doi.org/10.1186/s12889-026-28193-4.

Highlights

Full vaccination remains low in Konye despite high initial vaccine contact.

Respecting all vaccination appointments, having a higher household income and recognizing vaccine side effects, strongly predict vaccine completion.

CHW outreach supports uptake, while conflict, distance, and fear, hinder access.

Findings inform context-specific immunization strategies in crisis settings.

Supplementary Information

The online version contains supplementary material available at https://doi.org/10.1186/s12889-026-28193-4.

Introduction

Immunization remains one of the most efficient, inexpensive, and cost-effective public health strategies for reducing childhood morbidity and mortality. Despite remarkable global progress, approximately 21.8 million infants remain unreached by routine vaccination services, and 13.8 million representing 70% of children missing DTP3 are classified as zero-dose (ZD) [1, 2]. In Sub-Saharan Africa, vaccine-preventable diseases continue to account for nearly three million childhood deaths annually, with one in five children still under-immunized despite the availability of free vaccination services [3]. To reverse these trends, the World Health Organization (WHO) has set ambitious global targets, including achieving at least 90% national vaccination coverage and 80% district-level coverage under the Global Immunization Vision and Strategy (GIVS) 2006–2015, goals reiterated in the Global Vaccine Action Plan (2011–2020) and the Immunization Agenda 2030 [4]. However, achieving and sustaining such targets remains difficult for many low- and middle-income countries due to health system constraints, inequities, and contextual barriers [5].

Evidence from low- and middle-income countries shows that vaccination uptake is influenced by a complex interplay of factors operating at multiple levels [6]. At the individual and household level, maternal education, socioeconomic status, and caregiver knowledge and perceptions of vaccines are key determinants [7]. Health service–related factors, including physical access to health facilities, vaccine availability, quality of service delivery, and interactions with healthcare providers, also play a critical role [8]. In addition, broader contextual influences such as geographic barriers, insecurity, misinformation, cultural norms, and trust in the health system significantly affect whether children initiate and complete their vaccination schedules [9].

For the purpose of this study, a child is considered “completely vaccinated” if they have received all age-appropriate vaccines according to the national Expanded Programme on Immunization (EPI) schedule [10]. Gaps in complete vaccination are often linked to barriers at multiple levels, and understanding these barriers is essential for identifying effective intervention strategies [7].

Cameroon has made considerable efforts through its Expanded Programme on Immunization (EPI), which provides free vaccines to children under two years of age. Between 2000 and 2013, national coverage for DTP1 and DTP3 increased substantially from 66% to 95% and 62% to 89%, respectively [11]. By 2019, DTP1 and DTP3 coverage had declined to 75% and 67%, and the COVID-19 pandemic further disrupted service delivery, contributing to an estimated 149,133 ZD children in 2021 [12].

The ongoing socio-political crisis in the Northwest and Southwest regions has greatly exacerbated immunization challenges [13]. The Southwest Region (SWR) now ranks among the areas with the highest ZD burden nationally [12]. Nearly one million people have been displaced, and health service delivery has been severely disrupted due to the destruction and looting of health facilities, violence against health workers, and widespread insecurity [13]. As a result, immunization coverage in some localities has dropped to as low as 34%, among the lowest nationally [12]. Beyond conflict-related barriers, demand-side issues such as caregiver misconceptions, misinformation, mistrust in the health system, and deeply rooted religious or cultural beliefs (e.g., infertility fears or concerns that vaccines contain microchips), continue to undermine vaccine uptake [14, 15]. These factors often intersect with poverty, low literacy levels, and poor physical access to services [16].

Although Cameroon implements multiple routine immunization delivery strategies including; fixed-site services, same-day outreach, multiday mobile strategies, and periodic intensification of routine immunization (PIRI), coverage gaps remain substantial in crisis-affected districts [13]. The Konye Health District (KHD) is among the hardest hit, reporting only 31.5% vaccination coverage for all six vaccine-preventable diseases [17]. This critically low coverage heightens the risk of outbreaks within the district and across other conflict-affected communities.

However, there is limited context-specific evidence on how socio-demographic, health system, and conflict-related factors interact to influence vaccination uptake in KHD, as well as on the barriers to complete vaccination and the effectiveness of existing interventions in this setting [18].

Given these gaps, there is a critical need to generate context-specific evidence on the determinants of vaccination uptake. Therefore, this study aimed to assess the socio-demographic, health service–related, and contextual factors associated with complete vaccination among children aged 0–59 months in KHD, and to explore the barriers and facilitators influencing uptake. By linking these determinants to observed coverage outcomes, the study seeks to inform targeted, evidence-based interventions to strengthen immunization delivery in conflict-affected settings.

Objective of the study

This study seeks to address these evidence gaps by providing an in-depth assessment of childhood immunization performance and barriers in the Konye Health District (KHD). Specifically, the study aimed: To assess the proportion of children aged 0–59 months who are completely vaccinated in KHD; identify the barriers to vaccination uptake at different levels in KHD; examine interventions implemented by the state and its partners to address poor vaccination uptake in KHD.

Method and material

Study design, setting and population

This study was a community-based cross-sectional mixed-methods study conducted from March 2023 to May 31, 2023, in the Konye Health District (KHD), located in the Southwest Region of Cameroon (Fig. 1). The study population comprised parents and guardians (both male and female) of children aged 0–59 months, healthcare workers (HCWs), Community health workers (CHWs) residing in KHD.

Fig. 1.

Konye health district map. Source: District Health Service Konye

Sample size determination

The required sample size was calculated using the single population proportion formula (Cochran formula) with an assumption of 95% (CI), 5% margin of error, 0.58 proportion of children vaccinated, based on a previous study carried out in West Cameroon by Russo et al. [19].

Where

n = estimated sample size

z = 1.96

p = 0.58

q = 1- p  = 1-0.58 = 0.42

e = 0.05

n = (1.96) ^ 2 (0.58) (0.42)/0.05*0.05

= 374 participants

After adding a 10% non-response rate, the final sample size was 411 caregivers of children aged 0–59 months.

Sampling technique

A multistage sampling approach was employed for this study. First, purposive sampling was used to select the Konye Health District (KHD) because it is one of the lowest-performing districts among the 21 health districts in the Southwest Region of Cameroon. From the eight health areas in KHD, four including; Wone, Mbakwasupe, Konye, and Ikiliwindi, were then selected through simple random sampling (Table 1). Probability proportional to size was subsequently applied to allocate the quantitative sample across these areas. Balloting was made to select quarters and Households were randomly selected to administer questionnaires. A mixed sampling strategy combining systematic random and purposive sampling was used within the selected health areas. For the quantitative component, caregivers of children aged 0–59 months were recruited through systematic random sampling of households, while Community Health Workers (CHWs) and facility leaders were purposively selected. For the qualitative component, healthcare workers and CHWs were also purposively recruited to participate in focus group discussions. This integrated sampling approach ensured adequate representation from both community members and health system actors, allowing for triangulation and a comprehensive understanding of the factors influencing vaccine uptake in the district.

Table 1.

Study population proportionate to the health area population

Health area	Total population	Study population
Mbakwa Supe	10,939	60
Wone	10,463	60
Konye	25,164	127
Ikiliwidi	32,863	165
Total	79,429	412

Data collection method

Data were collected using both quantitative and qualitative approaches. For the quantitative component, a structured questionnaire was administered to caregivers. The questionnaire was developed specifically for this study based on a review of relevant literature, the study objectives, and contextual factors related to vaccine uptake in conflict-affected settings. It had not been previously published. The tool comprised three sections: (i) sociodemographic characteristics of caregivers, (ii) the child’s vaccination status, and (iii) potential barriers to vaccination uptake in the Konye Health District (KHD). An English version of the questionnaire has been provided as a supplementary file (appendices-questionnaire).

For the qualitative component, a focus group discussion (FGD) guide adapted from the World Health Organization Behavioural and Social Drivers of Vaccination (BeSD) tool was used to explore underlying reasons for low vaccination coverage in the district [20].

Three data collectors were recruited and trained for one day by the principal investigator. The training covered the purpose of the study, use of data collection instruments, obtaining informed consent, household child-selection procedures, interview techniques, extraction of information from immunization cards, and overall field procedures.

FGDs were conducted with three homogenous stakeholder groups: healthcare workers, caregivers, and Community Health Workers (CHWs). Healthcare workers were engaged on missed opportunities for vaccination, health information delivery systems, and challenges encountered in providing immunization services. Caregivers were probed on their knowledge, attitudes, and perceived barriers to vaccinating their children. CHWs participated in a separate FGD to discuss mobilization challenges within their communities. Each FGD consisted of 12 participants including; a moderator, recorder, and timekeeper and lasted approximately one hour. In total, three FGDs were conducted, ensuring diversity in educational background, number of children, and socioeconomic status.

Participants for FGDs were selected based on the following characteristics:

• Chiefs of health centres involved in immunization activities and residing in the KHD for at least one year.

• Community Health Workers actively engaged in vaccination activities for at least one year.

• Men and women with children aged 0–59 months who had lived in the KHD for at least one year.

Inclusion criteria for quantitative data collection of participants (caregivers):

• Children aged 0–59 months and their parents or guardians.

• Parents or guardians aged 21 years or older.

• Ability to communicate in English, French, or Pidgin English.

• Residency in one of the health areas within the Konye Health District.

Data analysis

Data collected through the structured questionnaire were entered using the Kobo Collect application and subsequently exported to Microsoft Excel for cleaning and verification. Data quality management involved checking for completeness, consistency, and accuracy before analysis. The data was cleaned and prepared for tabulation using statistical data analysis software SPSS Version 26. Frequencies and other descriptive statistics were done. Bivariate analysis was conducted to examine association between dependent and independent variables; Odds Ratios (ORs) and their 95% CIs were calculated. Then, all variables that had a p-value less than 0.2 in the bivariate analysis was included in the multiple logistic regression analysis models to determine the factors associated with immunization coverage among children aged 0 to 59 months. Adjusted Odds Ratio (AOR) with their 95% CIs were computed to determine the true association. Data was categorized into three groups (socio-demographic characteristics, vaccination status and information on the child, knowledge of vaccine and vaccine preventable diseases) to see the association of explanatory variables with outcome variable. Then, from each of the groups, variables that had p-value of less than 0.05 were entered into the final model.

The qualitative component was designed to complement the quantitative findings by providing in-depth insights into the contextual, behavioural, and health system factors influencing vaccination uptake.

A total of three focus group discussions (FGDs) were conducted among purposively selected participants, including community health workers (CHWs), caregivers of children aged 0–59 months, and healthcare providers involved in immunization service delivery. Participants were selected based on their direct involvement in or experience with routine immunization activities in the Konye Health District (KHD). The number of FGDs was determined based on data saturation, defined as the point at which no new themes or insights emerged during discussions.

Each FGD consisted of 6–8 participants, ensuring adequate diversity of perspectives while maintaining an environment conducive to active participation and discussion. A semi-structured discussion guide was used to explore key themes, including barriers and facilitators to vaccination uptake, perceptions of immunization services, and the role of community-based strategies.

All discussions were conducted in a language familiar to participants, audio-recorded with consent, and subsequently transcribed verbatim. Transcripts were carefully reviewed and verified against the original recordings to ensure accuracy and completeness.

Data were analysed using a thematic analysis approach following Braun and Clarke’s six-phase framework. This involved familiarization with the data, generation of initial codes, searching for patterns across codes, reviewing and refining themes, defining and naming themes, and producing the final report. Coding was conducted manually using Microsoft Excel, allowing for systematic organization and comparison of data across transcripts.

The qualitative findings were used to contextualize and explain the quantitative results, particularly by elucidating how identified determinants of vaccination uptake operate within the local context. This triangulation strengthened the overall interpretation of study findings and supported a more comprehensive understanding of barriers and facilitators to complete vaccination in this conflict-affected setting.

Ethics statement

Ethical clearance was obtained from the University of Buea, Faculty of Health Sciences, Institution Review Board with reference number: 2023/316/UB/D/HOD/ PHH/FHS. Administrative clearance was obtained from the Regional Delegation of Public Health South West region, Cameroon with reference number: R11/MINSANTE /SWR/RDPH /PS/631/663. Clearance was also obtained from the Konye district health service before the study. Permission to work in the different health areas was obtained from the various chiefs of centres. Advocacy was done with traditional rulers, key informants and representatives of nonstate.

armed groups before the study could begin. Individual consent was also sought before data collection.

Results

As seen in Table 2 below, a total of 412 respondents who took part in the study (Table 1), the mean age of the participants was 30.1 ± 6.5. 392 (95.1%) were females and 331 (80.3%) were within the age group 21–35. The dominant profession 166 (40.3%) was farming and 224 (54.4%) had attended secondary education. Most of the respondents 275 (66.7%) were married and Christianity was the dominant religion. About 205 (49.8%) used public transport as their transportation means and 231 (56.1%) monthly income was less than 25,000FCFA. Among the children included in the study, 55.1% were male and 44.9% were female, indicating a slight male predominance in the sample. Most 314 (76.2%) delivered in the hospital and 189 (45.9%) distance to health facility was moderate.

Table 2.

Socio-demographic variables respondents

Variable	Category	Frequency	Percentage
Gender of the respondent	Female	392	95.1
	Male	20	4.9
Age group (years)	21–35	331	80.3
	36–50	79	19.2
	50+	2	0.5
Profession	Civil servant	12	2.9
	Farming	166	40.3
	House wife	44	10.7
	Private sector	48	11.7
	Student	75	18.2
	Unemployed	67	16.3
Education	No formal	7	1.7
	Primary	143	34.7
	Secondary	224	54.4
	Tertiary	38	9.2
Matrimonial status	Divorced	10	2.4
	Married	275	66.7
	Single	119	28.9
	Widowed	8	1.9
Religion	Christian	397	96.4
	Muslim	1	0.2
	Others	14	3.4
Means of transport	Private	17	4.1
	Public	205	49.8
	Trekking	190	46.1
Average income (x1000FCFA)	< 25	231	56.1
	100+	16	3.9
	25–50	118	28.6
	51–100	47	11.4
Gender of the respondent’s child	Female	185	44.9
	Male	227	55.1
Place of delivery	Home	98	23.8
	Hospital	314	76.2
Means of transportation	On foot	233	56.6
	Private	8	1.9
	Public	171	41.5
Distance to HF	Close to HF	106	25.7
	Far	117	28.4
	Moderate	189	45.9
	Total	412	100

Figure 2 revealed that of the total of 412 children aged 0–59 months assessed, 396 (96%) had received at least one dose of vaccine, 239 (58%) were completely vaccinated, and 16 (4%) were zero-dose children.

Fig. 2.

Proportion of children who were completely vaccinated

The bivariate logistic regression analysis on Table 3 showed that several factors were significantly associated with complete vaccination status among children aged 0–59 months. Compared with divorced caregivers, both single caregivers (COR = 5.714, 95% CI: 1.163–28.075, p = 0.032) and married caregivers (COR = 6.185, 95% CI: 1.289–29.679, p = 0.023) had higher odds of having fully vaccinated children. Children from internally displaced person (IDP) households were less likely to be completely vaccinated than those from non-IDP households (COR = 0.337, 95% CI: 0.196–0.582, p < 0.001). Transportation was also important, as caregivers who trekked to the health facility (COR = 0.187, 95% CI: 0.042–0.842, p = 0.029) or used public transport (COR = 0.164, 95% CI: 0.037–0.735, p = 0.018) were less likely to complete their children’s vaccination compared with those using private transport. Household income was positively associated with complete vaccination, with caregivers earning 25–50 thousand FCFA (COR = 1.579, 95% CI: 1.006–2.479, p = 0.047), 51–100 thousand FCFA (COR = 4.917, 95% CI: 2.202–10.979, p < 0.001), and 100 thousand FCFA or more (COR = 4.371, 95% CI: 1.213–15.746, p = 0.024) being more likely to fully vaccinate their children than those earning less than 25 thousand FCFA. Caregivers aged 31–45 years were less likely to have fully vaccinated children compared with those aged 0–15 years (COR = 0.387, 95% CI: 0.219–0.685, p = 0.001). Children delivered in hospitals were much more likely to be completely vaccinated than those delivered at home (COR = 6.249, 95% CI: 3.743–10.432, p < 0.001), and the presence of a vaccination unit in the area was also strongly associated with complete vaccination (COR = 4.711, 95% CI: 2.714–8.176, p < 0.001). In addition, caregivers living at a moderate distance (COR = 0.370, 95% CI: 0.209–0.652, p = 0.001) or far from a health facility (COR = 0.108, 95% CI: 0.058–0.201, p < 0.001) were less likely to complete vaccination than those living close to a facility.

Table 3.

Factors Associated with complete vaccination status in children aged 0–59 months using the bivariate logistic regression Analysis

Complete vaccination status			95%CI for COR
Variable	Category	COR	Lower	Upper	p-value
Matrimonial status	Single	5.714	1.163	28.075	0.032
	Married	6.185	1.289	29.679	0.023
	Divorced	1
IDP	Yes	0.337	0.196	0.582	0.000
	No	1
Means of transport	Trekking	0.187	0.042	0.842	0.029
	Public	0.164	0.037	0.735	0.018
	Private	1
Average monthly income (X1000FCFA)	51–100	4.917	2.202	10.979	0.000
	25–50	1.579	1.006	2.479	0.047
	100+	4.371	1.213	15.746	0.024
	< 25	1
Age group (years)	46+	0.649	0.311	1.354	0.249
	31–45	0.387	0.219	0.685	0.001
	16–30	0.988	0.619	1.579	0.960
	0–15	1
Place of delivery	Hospital	6.249	3.743	10.432	0.000
	Home	1
Presence of vaccination unit	Yes	4.711	2.714	8.176	0.000
	No	1
Distance to HF	Moderate	0.370	0.209	0.652	0.001
	Far	0.108	0.058	0.201	0.000
	Close	1
Means of transport	Public	0.667	0.448	0.995	0.047
	On foot	1

The multivariable logistic regression analysis on Table 4, examined the independent factors associated with complete vaccination status among children aged 0–59 months. By adjusting for potential confounders, the model identified which caregiver, socioeconomic, access, and health-related variables significantly influenced the likelihood of a child being fully vaccinated. Caregivers who did not know CHWs in their area were less likely to have completely vaccinated children than those who knew CHWs (AOR = 0.197, 95% CI: 0.041–0.938, p = 0.041). Children whose caregivers went to the health facility on foot (AOR = 0.049, 95% CI: 0.004–0.600, p = 0.018) or used public transport (AOR = 0.060, 95% CI: 0.005–0.706, p = 0.025) were less likely to be fully vaccinated compared with those using private transport. Household income was positively associated with complete vaccination: caregivers earning 25–50 thousand FCFA (AOR = 3.380, 95% CI: 1.565–7.300, p = 0.002) and 51–100 thousand FCFA (AOR = 3.695, 95% CI: 1.139–11.988, p = 0.030) had higher odds of complete vaccination than those earning less than 25 thousand FCFA, while income of 100 thousand FCFA and above was not significant (AOR = 2.510, 95% CI: 0.305–20.683, p = 0.392). Caregivers aged 36–50 years were less likely to have fully vaccinated children than those aged 21–35 years (AOR = 0.344, 95% CI: 0.160–0.737, p = 0.006). Distance to the health facility was also significant, with caregivers living at a moderate distance (AOR = 0.332, 95% CI: 0.141–0.782, p = 0.012) or far away (AOR = 0.123, 95% CI: 0.041–0.371, p < 0.001) being less likely to complete vaccination than those living close. Caregivers who sought treatment from roadside drug vendors were less likely to have fully vaccinated children than those who used health facilities (AOR = 0.292, 95% CI: 0.111–0.767, p = 0.012). In contrast, caregivers who said vaccines have side effects were more likely to have completely vaccinated children (AOR = 4.538, 95% CI: 2.227–9.246, p < 0.001), and those who respected all vaccination appointments had the highest odds of complete vaccination (AOR = 20.372, 95% CI: 8.625–48.117, p < 0.001). Receiving vaccination information from CHWs was not significantly associated with complete vaccination (AOR = 2.754, 95% CI: 0.790–9.607, p = 0.112).

Table 4.

Factors Associated with complete vaccination status in children aged 0–59 months using Multivariable Logistic Regression Analysis

Completely vaccinated			95%CI for AOR
Variable	Category	AOR	Lower	Upper	p-value
Know CHWs in my area	No	0.197	0.041	0.938	0.041
	Yes	1
Means of transport	On food	0.049	0.004	0.600	0.018
	Public	0.060	0.005	0.706	0.025
	Private	1
Average monthly income (X1000FCFA)	51–100	3.695	1.139	11.988	0.030
	25–50	3.380	1.565	7.300	0.002
	100+	2.510	0.305	20.683	0.392
	< 25	1
Age group (years)	36–50	0.344	0.160	0.737	0.006
	21–35	1
Distance to HF	Moderate	0.332	0.141	0.782	0.012
	Far	0.123	0.041	0.371	0.000
	Close	1
Attended postnatal care	Yes	0.042	0.001	1.461	0.080
	No	1
Where you take your check when sick	Road side drugs	0.292	0.111	0.767	0.012
	Health facility	1
Vaccines have side effects	Yes	4.538	2.227	9.246	0.000
	No	1
Respect all vaccination appointments	Yes	20.372	8.625	48.117	0.000
	No	1
Have received info on vaccination from the CHWs	Yes	2.754	0.790	9.607	0.112
	No	1

Economic barrier influencing vaccination uptake

FGDs indicated lack of awareness, fear of side effects, mothers giving less attention to child immunization, and very low male involvement in vaccination. A 34-year-old married woman explained:

“A friend of mine living in the rural area has five children. She didn’t give birth at the health facilities and none of her children were vaccinated because her husband didn’t have money to give her to transport the children to the health facilities for vaccination.” – Caregiver, KHD.

Fear of adverse effects following immunization

Another barrier raised was fear of adverse reactions or side effects, which often discourages mothers from returning for subsequent doses. A 30-year-old woman shared:

“Most of the children automatically develop fever and unusual discomfort for at least three days after getting vaccinated which is a frustrating situation for families till they recovered. I fear vaccination might kill my child. So, I never go again to vaccinate my child because I have seen the episode.” – Caregiver, KHD.

Poor quality and inadequacy of health information dissemination

Health workers noted that mass health education sessions were often ineffective because they did not consider the diverse literacy levels and understanding of mothers and caregivers. A 39-year-old male health facility manager stated:

“On providing quality health information, we do have problems. It is not fully understood by our clients. It doesn’t meet the expectations of the communities (specifically rural communities) in conveying the right kind information regarding immunization in casting out misconceptions. Yet, information we have provided didn’t bring the desired behavioural change.” – Health Facility Manager, KHD.

Impact of conflict and insecurity on vaccination uptake

Participants also highlighted the insecurity in the area, which frequently disrupts health services. A 40-year-old female chief of centre explained:

“Frequent lockdowns and gun battles push us to temporarily close health facilities, missing vaccination appointments. This uncertainty makes some parents not to come for appointments.” – Chief of Centre, KHD.

This underscores the detrimental impact of the crisis on vaccination uptake and the health care delivery system in KHD.

Measures already implemented to improve vaccination uptake in KHD

Role of community health workers in improving coverage

To address poor vaccination uptake, community health workers (CHWs) are actively involved in community-level mobilization. A 48-year-old CHW described:

“I was selected by my community and recruited by the state to promote health in my community. I carry out home visits, educate the parents on the importance of vaccination, remind them of their appointment dates and also search for children lost to follow up in my area.” – CHW, KHD.

CHWs also participate in planning vaccination activities and organizing outreach sessions, which help vaccinate children in distant communities through the REACH EVERY CHILD (RED) approach.

Intensification of outreach and community-based strategies

Health providers consistently mentioned outreach as a major strategy for improving vaccine uptake. A 34-year-old uneducated mother said:

“I use outreach service to vaccinate my children. I remember the date from the announcement and since the outreach site is not too far, I’m vaccinating my children regularly by using such advantage. If other health problems happen to my children, I take them to the health facility; however, in most of the cases for utilizing immunization services, I use the outreach post. I am happy that the nurses bring the vaccines to us.” – Caregiver, KHD.

Use of PIRI, SIAs, and partner-supported interventions

Additional strategies include PIRI, SIAs, and partner-supported outreach. A 40-year-old female chief of center noted:

“Periodic intensification of immunization activities (PIRI), supplementary immunization activities and the intensification of outreach activities put in place by GAVI, WHO and the state have contributed to improve the vaccination coverage in my health area.” – Chief of Centre, KHD.

These strategies allow children to be vaccinated even at home during SIAs, reducing the number of zero-dose children.

Leveraging maternal health services (ANC and PNC) to promote vaccination

Maternal health visits also create opportunities for vaccination counselling. A 30-year-old woman reported:

“When a mother took her child to health facility (to the health professionals), it is a good opportunity for getting advice and guidance on the initiation time of vaccines, when it should get completed and the importance of completing immunization for children. So, ANC and PNC follow up has helped to educate and remind us on why we need to vaccinate our children.” – Caregiver, KHD.

Door-to-door and community-based vaccination in hard-to-reach areas

Conflict and distance have been addressed through mobile and door-to-door vaccination. A 32-year-old married woman shared:

“Even if I don’t go to the health center for vaccination, the nurse brings the vaccines to my village once a month, on the last Friday of the month. Sometimes they even move from door to door to vaccinate our children.” – Caregiver, KHD.

This reflects how outreach activities, campaigns, and PIRI are sustaining vaccine uptake in conflict-affected settings.

Discussion

This study investigated barriers to vaccine uptake among children aged 0–59 months amidst ongoing civil strife in Konye Health District (KHD). Data were collected from parents and guardians responsible for the children’s healthcare decisions. The mean age of respondents was 30.1 ± 6.5 years, consistent with findings from Sudan. Most respondents were female (95.1%), aged 21–35 years (80.3%), predominantly farmers (40.3%), and had completed secondary education (54.4%). A majority were married (66.7%), practiced Christianity, and reported low monthly income (< 25,000 FCFA) [21]. Additionally, 76.2% delivered in a health facility, and 45.9% lived at a moderate distance from health facilities. Saidu et al. (2021) similarly found that married women with low monthly income were the primary caregivers responsible for child health decisions in the North West and South West regions during the sociopolitical crisis. This highlights socioeconomic vulnerabilities described by Saidu et al., who noted that crisis-related displacement and livelihood disruptions further constrain access to routine immunization services [22].

Even though 96% of children had received at least one vaccine, only 58% of children were completely vaccinated according to the vaccination schedule. This is below the WHO recommended 80% coverage threshold. This proportion is comparable to findings by Yakum et al. (2023) in conflict-affected regions of Cameroon, highlighting the impact of conflict and service disruptions on routine immunization [23].

Several child-level and caregiver-level factors were associated with vaccination completion. Male children had higher odds of being completely vaccinated than female children, reflecting gendered differences in health-seeking behaviour documented in similar contexts [24]. Place of delivery was also critical: children born in health facilities were six times more likely to be completely vaccinated than those born at home, likely due to early vaccination education and integration with other health services [25].

Maternal education emerged as a strong determinant: caregivers with secondary or higher education were twice as likely to complete child immunization compared to non-literate mothers. This finding aligns with studies in Northern Nigeria and Sudan, indicating that educated caregivers have better health literacy, enabling them to understand the importance of vaccination schedule [26]. Similarly, maternal health service utilization, including antenatal care (ANC) and postnatal care (PNC) were associated with higher vaccination completion, as visits provide opportunities for counseling and integration with child immunization services. This study’s findings are highly consistent with those of Budu et al. (2021), who analyzed 29 nationally representative surveys across sub-Saharan Africa and found out that ANC and PNC were far more likely to have children who were fully immunized, likely because these visits offer opportunities for counseling, education, and linkage to immunization services [27].

Household and contextual factors also influenced vaccination. Children from farming households or higher-income families (> 50,000 FCFA/month) were more likely to be completely vaccinated, likely reflecting access to information and resources. This study’s findings show strong similarities to that of Kundu et al. (2023) in Bangladesh, who found out that household socioeconomic status influenced vaccination outcomes, with children from farming and slightly more stable-income households more likely to be vaccinated [28]. Conversely, internally displaced persons (IDPs) faced challenges due to displacement, poverty, and lack of information, negatively affecting child vaccination coverage. Distance from health facilities remained a persistent barrier; children living further away had lower vaccination coverage, especially in conflict-affected areas where travel is risky. Similarly, this study aligns with the findings from Mogadishu et al. (2025) in Somalia, which report that internally displaced persons (IDPs) face significant challenges such as; displacement, poverty, and lack of reliable health information, that negatively affect vaccination uptake [29].

Caregivers’ knowledge about vaccines and side effects strongly correlated with vaccination status. Those aware of possible side effects were 4.5 times more likely to be completely vaccinated, suggesting that accurate and contextualized information increases caregiver confidence and vaccine uptake. In contrast, misinformation or fear of adverse effects contributed to dropouts, as confirmed by qualitative data from focus group discussions (FGDs). This finding is similar to the results of Matos et al. (2024 in South Brazil, who reported that caregivers’ perceptions and understanding of routine childhood vaccines shaped their confidence in the immunization process. In both studies, fear, misinformation, and unclear communication were major contributors to vaccine hesitancy and dropout, as mothers expressed anxiety about adverse reactions when health workers did not provide adequate explanations [30].

Interventions implemented to improve vaccine uptake in KHD

Community health workers (CHWs) played a central role in improving vaccine uptake. Awareness of CHWs and their mobilization efforts significantly increased both initiation and completion of vaccination. Our study findings align closely with Gibson et al. (2023), which highlighted the vital contribution of CHWs to improving vaccination coverage across low-resource settings. Both studies emphasize that CHWs are effective because they serve as trusted community actors, strengthen caregiver awareness, and provide culturally contextual vaccine education [31].

Supplementary immunization activities (SIAs) and periodic intensification of routine immunization (PIRI) were employed to reach children in high-risk zones. These strategies, coupled with outreach and door-to-door vaccination campaigns, mitigated the effects of geographic and transport barriers, as caregivers expressed preference for nearby posts or home-based visits. The use of SIAs and PIRI in our study is consistent with findings from Chakrabarti et al. (2019), who demonstrated that targeted SIAs significantly improve routine vaccination coverage in low-income countries [31]. Just as in KHD, SIAs helped mitigate structural barriers such as distance, transportation constraints, and irregular routine services. Both studies show that SIAs are particularly valuable where health systems are strained, whether due to conflict, geographic isolation, or resource shortages [31].

Integration of immunization with disease surveillance strengthened both vaccine coverage and monitoring. CHWs trained in surveillance contributed to better reporting and early detection of cases, such as acute flaccid paralysis (AFP), thereby supporting the Global Polio Eradication Initiative even under conditions of insecurity. This synergy between immunization and surveillance highlights how multi-sectoral interventions enhance public health outcomes. Similar to Gemechu et al. (2025), this study found that strengthening surveillance systems, particularly through CHWs enhanced vaccine delivery and monitoring [32]. In both contexts, CHWs trained in community-based surveillance contributed to improved reporting and early detection of priority conditions, supporting broader public health goals.

Functional appointment systems and consistent reminders from CHWs further supported schedule adherence. Respecting vaccination appointments emerged as one of the strongest predictors of being completely vaccinated, and qualitative insights emphasized that insecurity and poor information flow contributed to missed visits. This underscores the need for tailored, context-specific health education strategies adapted to literacy levels and local circumstances. Likewise, the emphasis on schedule adherence in this study aligns with the findings of Abor et al. (2022), who identified respecting vaccination appointments as a strong predictor of being completely vaccinated. Both studies reported that CHW-led reminders and interpersonal communication significantly reduced missed visits [33].

Fear of side effects, a barrier identified in FGDs, was countered by health education campaigns integrated into ANC, PNC, and CHW home visits. These interventions provided caregivers with clear, contextualized information about expected mild reactions, reducing anxiety and promoting vaccine completion. This finding is similar to the findings of Janik et al. (2022), who showed that providing clear, contextual information about expected side effects reduced anxiety among pregnant women, this study found that integrating health education into ANC, PNC, and CHW home visits effectively addressed caregivers’ fears about mild post-vaccination reactions [34].

Gender dynamics and household decision-making also shaped vaccine uptake. Male children were more likely to be vaccinated, reflecting paternal authority and gender norms influencing health-seeking behaviour. Gender dynamics observed in this study also mirror patterns reported in Ethiopia by Assefa et al. (2025), where decision-making power within households significantly shaped vaccine acceptance [24]. Both studies found that male authority often influenced health-seeking behaviour, and in both settings male children were more likely to be vaccinated. The present study, however, highlights that these gender norms were further complicated by conflict-related vulnerabilities, emphasizing an even stronger need for gender-responsive strategies that engage both men and women equally.

In summary, despite global progress in immunization, children in civil strife areas like KHD face multiple barriers, including socio-demographic constraints, caregiver knowledge gaps, household income limitations, gender norms, displacement, and geographic access challenges. However, CHW-led interventions, SIAs, outreach campaigns, and integration with health services have demonstrated measurable improvements in coverage. These findings highlight the importance of multi-pronged, context-specific strategies to achieve universal immunization goals.

Conclusion

This study demonstrates that while initial vaccine acceptance in Konye Health District (KHD) is high, with 96% of children aged 0–59 months receiving at least one vaccine dose, only 58% were completely vaccinated according to the vaccination schedule. This coverage falls below the WHO recommended threshold of 80% and highlights gaps in ensuring complete immunization for all children in the district. The findings provide a clear picture of the proportion of children completely vaccinated in KHD and underscore the need for sustained efforts to improve routine immunization.

The study identified multiple barriers to vaccine uptake at individual, household, community, and systemic levels. Child-level factors, such as sex and place of delivery, were associated with vaccination completion, with male children and those born in health facilities more likely to be completely vaccinated. Caregiver-level determinants—including maternal education, health-seeking behaviours, knowledge about vaccines, and attendance at antenatal and postnatal care—strongly influenced vaccination outcomes. Household and contextual factors such as income, occupation, displacement status, and distance to health facilities further impacted vaccine coverage. Qualitative data reinforced these findings, revealing how insecurity, fear of side effects, and limited access to information exacerbate under-vaccination. Collectively, these barriers illustrate the complex interplay of socio-demographic, cultural, and logistical factors in shaping vaccine uptake in a conflict-affected context.

Finally, the study highlighted interventions implemented by the state and partners to improve vaccination coverage in KHD. Strategies such as community health worker (CHW) engagement, outreach activities, supplementary immunization activities (SIAs), and periodic intensification of routine immunization (PIRI) have shown positive effects in improving both initial vaccine uptake and schedule completion. Integration of immunization with disease surveillance, appointment reminders, and caregiver mobilization through CHWs further strengthened service delivery. These measures demonstrate that multi-pronged, context-specific interventions can partially overcome the barriers posed by conflict, displacement, and geographic constraints.

In summary, despite high initial acceptance, complete vaccination coverage remains suboptimal in KHD due to a combination of child, caregiver, household, and systemic barriers. Existing interventions by the state and partners, particularly CHW-led outreach and PIRI/SIAs, have improved access and uptake but need to be scaled up and sustained. Addressing the identified barriers through continued community engagement, targeted health education, improved access to health facilities, and context-sensitive strategies is critical to achieving universal immunization and protecting children against vaccine-preventable diseases in KHD.

Abbreviations

ANC

Antenatal Care

AOR

Adjusted Odds Ratio

CHWs

Community Health Workers

CI

Confidence Interval

DHIS2

Demographic Health Information System 2

DTP

Diphtheria–Tetanus–Pertussis

EPI

Expanded Programme on Immunization

FGD

Focus Group Discussion

GIVS

Global Immunization Vision and Strategy

GVAP

Global Vaccine Action Plan

HCWs

Health Care Workers

IA2030

Immunization Agenda 2030

KHD

Konye Health District

OR

Odds Ratio

SWR

South West Region

UNHCR

United Nations High Commissioner for Refugees

WHO

World Health Organization

Authors’ contributions

R.M., S.N., and M.A.T. participated in the study design. R.M. oversaw pilot testing and data collection. R.M., S.N., M.A.T., A.C., G.J.G., and C.N.S. contributed to manuscript writing and review and approved the final version. R.M. and S.N. assisted with statistical analysis and interpretation of results. R.M. had overall responsibility for the study design, survey implementation, and oversight of data interpretation.

Funding

This work was self-sponsored by the authors.

Data availability

Data management for this study ensured participant confidentiality and secure storage. Survey responses were not accessible to participants at participating communities. Data were collected electronically and transmitted to Google Sheets linked to the project lead’s account, then securely exported to GitHub for storage. Access to the dataset was restricted to the study statistician for analysis. The datasets generated and analyzed during this study are not publicly available due to institutional regulations but can be obtained from the corresponding author upon reasonable request. All requests for access will be reviewed by the Ethics Committee of the Cameroonian Ministry of Public Health, the Regional Ethics Committee for Human Health Research for the South West Region, and the Institutional Review Board of the Faculty of Health Sciences, University of Buea, to ensure compliance with ethical and legal requirements.

Declarations

Ethics approval and consent to participate

Ethical approval for this study was obtained from the Institutional Review Board of the Faculty of Health Sciences, University of Buea (Reference: 2023/316/UB/D/HOD/PHH/FHS). Administrative authorization was also obtained from the Regional Delegation of Public Health for the South West Region (Reference: R11/MINSANTE/SWR/RDPH/PS/631/663). Written informed consent to participate was obtained from all participants prior to data collection.

For participants between than 0–59 months, written informed consent was obtained from their parents or legal guardians.

For illiterate participants, the consent form was read and explained in the appropriate local language, and consent was obtained in the presence of a legally authorized representative, who confirmed voluntary participation.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.