High Second-Year Immunisation Coverage Alongside Persistent Newer Vaccine Hesitancy: A Mixed-Methods Study in Three Districts of Malawi

Abstract

Background/Objectives: Vaccines delivered after infancy remain vulnerable to missed uptake. Less is known about the determinants of second-year-of-life vaccine uptake in Malawi. This study assessed the completion of vaccines due after 12 months of age, caregiver confidence in newer vaccines, and associated factors in three districts of Malawi. Methods: A mixed-methods cross-sectional study surveyed 1177 caregivers. Logistic regression examined factors associated with caregiver-reported completion of vaccines due after 12 months among age-eligible children. Focus group discussions with caregivers and key-informant interviews with community volunteers and leaders were then analysed thematically to explain the survey findings. Results: Among 1287 age-eligible children, 94.2% completed second-year vaccines, although coverage of the Human papillomavirus (HPV) vaccine was lower. Distance over 5 kilometres from a facility was associated with lower odds of completion, while health worker reminders were associated with higher odds of vaccine completion (adjusted odds ratio 3.03, 95% confidence interval 1.61 to 5.88). Qualitative accounts highlighted defaulter tracing and infertility concerns about HPV (22.2%). Conclusions: Second-year coverage was high among caregivers reached by immunisation services, but distance and lower uptake of newer vaccines remained important gaps. Strengthening geographical access, communication about newer vaccines, and adequately resourced health-worker follow-up may improve completion.

1. Introduction

Despite the benefits, global uptake of new and second-year-of-life vaccines: human papillomavirus (HPV), typhoid conjugate vaccine (TCV), inactivated polio vaccine second dose (IPV2), and measles–rubella second dose (MR2) has encountered challenges [1]. In 2025, the World Health Organization (WHO) and United Nations Children’s Fund (UNICEF) estimated that only 33% of eligible girls aged 9–14 had received a first dose of the HPV vaccine, against a coverage target of 90%, and just 31% received the final HPV dose [2,3]. Likewise, the global second-dose measles coverage (MCV2) stood at 77%, well below the 95% required to interrupt transmission [3]. Malawi faces the same difficulties in reaching international vaccine goals. The 2024 Malawi Demographic and Health Survey (MDHS) estimated two-dose HPV coverage at 31% among women aged 15–17 years and MR2 coverage at 73% among children aged 24–35 months [4]. By contrast, the single dose of IPV1 captured by the survey reached 88% among children aged 12–23 months [4]. The two most recently introduced antigens are not yet reflected in national survey estimates: TCV, introduced in 2023, and IPV2, introduced in 2024 [4]. These figures indicate that the newer vaccines and the doses given beyond infancy remain the weakest points in the immunisation schedule.

These coverage deficiencies illustrate a well-documented vulnerability of the second year of life (2YL) and adolescent service delivery systems in sub-Saharan Africa [5,6]. Historically, routine immunisation has been structured around the first year of life, and in regions where the second-year visit is poorly implemented, children are significantly less likely to return for subsequent doses [5,6]. Recurring factors encompass carers’ lack of awareness regarding the necessity and timing of subsequent doses, coupled with a significant deficiency in defaulter-tracing and reminder mechanisms [7]. Other countries in the region have attributed these gaps to interruptions in vaccine supply, failures in cold-chain management, and inadequately trained healthcare personnel, as well as socio-economic and urban-rural disparities affecting the probability of follow-up visits [8,9]. Newly introduced adolescent vaccines present additional challenges. For instance, school-centred HPV administration consistently overlooks out-of-school girls and, even among those who are reached, inadequate follow-up, apprehensions regarding injections, safety rumours, and scepticism towards a new vaccine result in second-dose dropout.

The consequences of these discrepancies are significant. In 2024, the regional measles second-dose coverage in Africa was merely 55%, potentially leading to a disproportionate incidence of recent outbreaks, with an estimated 22.4 million children worldwide remaining unvaccinated for MCV2 [10,11]. Measles infection diminishes previously established immunity and increases vulnerability to other pathogens. Similarly, insufficient HPV vaccination sustains the risk of cervical cancer in a nation with some of the highest age-standardised incidence and mortality rates globally (around 75.9 and 49.8 per 100,000), directly hindering the WHO’s strategy for cervical cancer elimination [12,13]. In addition, inadequate or postponed TCV adoption perpetuates the prevalence of typhoid fever and, importantly, drug-resistant Salmonella Typhi, for which vaccination serves as a primary control strategy in conjunction with water and sanitation interventions [14]. Collectively, these trends suggest that the significant advancements made at birth and during early infancy are not being sustained into the second year of life and adolescence.

Malawi exemplifies this challenge and offers an informative setting in which to examine it. The country sustains comparatively high coverage for the vaccines delivered in the first months of life and maintains an extensive delivery infrastructure, including a dense network of health facilities and a longstanding cadre of community-based disease control and surveillance assistants (DCSAs), formerly known as health surveillance assistants. It has also introduced several newer antigens in rapid succession: HPV vaccine in 2019, typhoid conjugate vaccine in 2023, and a second dose of IPV in December 2024, alongside the phased roll-out of the malaria vaccine. Yet coverage of the doses scheduled beyond early infancy remains substantially lower, and the country continues to experience measles outbreaks despite this infrastructure: a prolonged epidemic that began in October 2024 produced 653 confirmed cases and one death across six districts and prompted a reactive MR campaign in mid-2025 [15]. This combination of strong early-infancy performance and delivery systems alongside persistent later-dose shortfalls and recurrent outbreaks makes Malawi a particularly instructive setting in which to ask why vaccines due after infancy are not completed [15].

Despite the policy relevance of these gaps, the determinants of low uptake of new and second-year-of-life vaccines in Malawi remain poorly understood. The existing evidence rests largely on secondary analysis of national household surveys, typically focuses on a single antigen or on the composite of “fully immunised” infant coverage, and is almost exclusively quantitative in design [16,17]. Much less is known from primary data that consider the several newer vaccines scheduled beyond infancy together. Caregiver confidence and community-level concerns about these newer antigens have rarely been documented directly. How such confidence intersects with structural determinants such as socioeconomic position, food insecurity and the frequency of contact with health workers is likewise under-explored. Establishing these determinants is a prerequisite for designing delivery and demand-generation strategies that sustain coverage across the full schedule rather than only in early infancy.

This study therefore examined the completion of, and confidence in, new vaccines and vaccines due after infancy among caregivers in three districts of Malawi, using primary data. The objectives were threefold: first, to estimate the completion of vaccinations due after 12 months of age among children in the three districts; second, to describe caregiver confidence in the newer vaccines and the concerns present in their communities; and third, to identify the factors associated with completion, with particular attention to socioeconomic position, food insecurity, and contact with health workers.

2. Materials and Methods

2.1. Study Design and Setting

This study used a mixed-methods cross-sectional design. It took place from September to October 2025 in three districts of Malawi, namely Chikwawa in the Southern Region, Kasungu in the Central Region, and Mangochi in the Eastern Zone of the Southern Region. The districts were selected to represent variation in geography, density of facilities, and the history of partner support. The quantitative component is reported in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology guidance (STROBE) [18]. The qualitative component is reported in accordance with the Consolidated Criteria for Reporting Qualitative Research (COREQ) [19], with the completed COREQ checklist provided in Table S1.

2.2. Participants and Sampling

We calculated the sample size using Cochran’s formula. We assumed that 85% of children had received the third dose of pentavalent vaccine [4]. This served as the proxy coverage indicator. We used a 95% confidence level and a 5% margin of error. We applied a design effect of 2 and a 5% allowance for non-response. This gave a target of 412 caregivers per district. The total target sample across the three districts was 1236.

We selected study communities in two steps. First, we obtained a list of all 129 health facilities providing immunisation services in the three districts. We also listed the villages in each facility’s catchment area. We randomly selected a total of 30 facilities (23% of the sampling frame) across the three districts. Second, we purposively selected villages within each selected catchment area based on accessibility and logistical feasibility.

In each selected village, we worked with the disease control and surveillance assistants (DCSAs) to identify households with at least one child under five years of age. We used DCSAs’ household registers for this purpose. Enumerators visited eligible households consecutively until the sample size was complete. Teams identified a central point or landmark in the village and walked in different directions. The house closest to the landmark was the first to be interviewed. Households where the caregiver was absent were not revisited and were replaced immediately.

A caregiver was defined as the adult primarily responsible for the health decisions of the child or children. Caregivers were eligible if they had lived in the study area for at least six months. All children under five in the household who were age-eligible for the vaccines assessed were included. Where a caregiver had more than one eligible child, each child was included. Standard errors were adjusted for clustering of children within households. We excluded caregivers with severe cognitive or communication difficulties that prevented an interview.

Trained enumerators administered a structured questionnaire in Chichewa. The research team translated the questionnaire into Chichewa. It was then back-translated to check accuracy. The questionnaire was piloted before data collection in Lilongwe. Interviews took place at household level within the catchment areas of the selected facilities.

2.3. Measures

The questionnaire captured caregiver and household characteristics, ownership of household assets, household food security, contact with immunisation services, confidence in the newer vaccines, and community concerns about those vaccines. Caregiver-reported vaccination status for vaccines due after 12 months was recorded for each eligible child, with reference to the child health passport where it was available.

A household wealth index was constructed from 15 asset indicators through principal components analysis, following the standard approach for asset-based measures of socioeconomic position [20]. The first principal component was retained as the wealth score. Households were then grouped into tertiles, labelled poorest, middle, and least poor.

Household food insecurity was measured using the Household Food Insecurity Access Scale, which records the occurrence and frequency of nine experiences of food access over the previous four weeks [21]. A summary score was calculated across the nine items. Households were then classified as food secure, moderately food insecure, or severely food insecure.

Distance to the nearest facility or outreach site was recorded in three bands, namely under two kilometres, two to five kilometres, and over five kilometres. Contact with services was captured through two items, namely whether the caregiver had received any reminder or follow-up communication, and whether a disease control and surveillance assistant or volunteer had reminded or followed up the caregiver about the child. Confidence in the safety of the newer vaccines was recorded on a three-level scale, namely very confident, slightly confident, and not confident. Community concerns were recorded from a list that included the belief that the HPV vaccine causes infertility.

2.4. Outcome Definition

The primary outcome was completion of all second-year-of-life vaccines (receipt of MR2) and newly introduced vaccines (IPV2). Analysis of the outcome was restricted to children aged 18 months or older, because younger children were not yet due for the second-year doses. Children whose caregiver could not state the vaccination status were excluded from the outcome analysis. This restriction produced an analytic sample of 1287 children for the outcome model. Descriptive measures of confidence and community concern were reported for the full sample of 1177 caregivers, because these measures did not depend on the age of the child.

2.5. Statistical Analysis

We summarised categorical variables using frequencies and percentages. Continuous variables were summarised using medians and interquartile ranges. Vaccine completion was described overall and by district. Associations between vaccine completion and each independent variable were first examined using univariable logistic regression models. Variables identified a priori based on their relevance from previous literature and the study objectives were entered simultaneously into a multivariable logistic regression model to estimate adjusted odds ratios with 95% confidence intervals. Covariates included district, household wealth tertile, household food insecurity, distance to the nearest health facility, caregiver literacy, caregiver confidence in newer vaccines, receipt of a health worker reminder, previous experience of vaccine stock-outs, and experiences of discouragement during vaccination visits. For categorical predictors, reference categories were specified in the regression models and are clearly reported in the tables. Odds ratios were estimated using logistic regression, with p-values obtained from Wald tests based on standard errors adjusted for clustering at the household level, because some caregivers contributed data for more than one child. The corresponding 95% confidence intervals were calculated using the Wald test method and the household-clustered robust standard errors. Missing data were handled using complete-case analysis. All participating caregivers were female; consequently, caregiver sex was not included in the regression analysis because the variable had no variation. Crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were reported. A two-sided p-value < 0.05 was considered statistically significant. Analyses were conducted using R version 4.5.2.

2.6. Qualitative Data Collection and Analysis

The qualitative component was designed to explain the survey findings, with particular attention to the completion gap and the concerns about the newer vaccines. Focus group discussions and key-informant interviews were conducted across the three districts. Focus group discussions were held with caregivers. Key-informant interviews were held with DCSAs, community immunisation volunteers, facility in-charges, nurses, teachers, community leaders, and religious leaders. Trained interviewers used semi-structured guides in the local language. Discussions were audio-recorded, transcribed, and translated into English where necessary.

The focus group discussions and key-informant interviews were conducted by trained research assistants. Data collectors had a minimum of a Malawi School Certificate of Education. The team was experienced in community data collection and had worked with the research team for four years. The research team trained and supervised the data collectors in the study objectives, the semi-structured guides and qualitative interviewing before fieldwork began. Pilot testing of data collection tools was conducted. The data collectors had no prior relationship with the participants. Participants were informed of the purpose of the study and the role of the data collectors at the point of consent.

Participants were sampled purposively. Recruitment continued until thematic saturation, defined as the point at which further discussions yielded no new codes. Six focus group discussions and 15 key-informant interviews were conducted across the three districts. Each focus group included six to eight caregivers.

Focus group discussions with caregivers were held face to face in community venues, including community meeting places and schools. Key-informant interviews were held at a location convenient to each informant. Only the participants and the data collectors were present. Each focus group lasted about 45 min. Field notes were taken during and after each session. Repeat interviews were not conducted. However, data were triangulated with health care workers at a data validation workshop.

Coding was carried out by two coders. Transcripts were hand-coded in Excel. Transcripts were not returned to participants. Participants did not provide feedback on the findings.

Transcripts were analysed thematically following the approach described by Braun and Clarke [22]. A deductive framework was first applied, organised around the quantitative findings, namely the role of reminders and follow-up, the concerns about the newer vaccines, and the channels of trusted communication. Inductive codes were then added for themes that arose from the data. Codes were grouped into themes, and illustrative quotations were selected to represent each theme. Integration of the two components was achieved through a joint display, in which each quantitative finding was placed alongside the qualitative evidence that helped to explain it.

2.7. Ethical Considerations

Ethical approval was obtained from the College of Medicine Research Ethics Committee (COMREC) (approval reference P.06/25-1638). All caregivers were provided with a participant information sheet and gave written informed consent in the local language before the interview. Data were anonymised at the point of collection.

3. Results

3.1. Caregiver and Household Characteristics

A total of 1177 caregivers were enrolled, comprising 527 in Chikwawa, 502 in Kasungu, and 148 in Mangochi. The median age of caregivers was 30 years, with an interquartile range of 24–37 years. Most caregivers lived in rural areas. Just over three quarters of caregivers were able to read or write. Food insecurity was widespread. Severe food insecurity was reported by 751 households (64 per cent), moderate food insecurity by 199 households (17 per cent), mild food insecurity by 53 households (4.5 per cent), and food security by 174 households (15 per cent). The full characteristics of the sample are presented in Table 1.

Table 1. Characteristics of caregivers and households (N = 1177).

Characteristic	Category	N (%)
District	Chikwawa	527 (44.8)
	Kasungu	502 (42.7)
	Mangochi	148 (12.6)
Caregiver literacy	Able to read or write	921 (78.3)
Marital status	Married, monogamous	808 (68.6)
	Married, polygamous	117 (9.9)
	Divorced	140 (11.9)
	Widowed	47 (4.0)
	Not married	65 (5.5)
Religion	Christian	955 (81.1)
	Muslim	159 (13.5)
	Other or none	63 (5.4)
Residence	Rural	1145 (97.0)
Wealth tertile	Poorest	393 (33.4)
	Middle	392 (33.3)
	Least poor	392 (33.3)
Food insecurity	Food secure	174 (15)
	Mild food insecure	53 (4.5)
	Moderately insecure	199 (17)
	Severely insecure	751 (64)
Distance to facility	≤5 km	924 (79)
	>5 km	253 (21)

Note. Percentages are of the full sample. Small numbers of missing values are not shown. Median household size was five persons.

3.2. Coverage of Second-Year and Newer Vaccines

Coverage differed markedly by antigen. Among children aged 18 months or older (N = 1087), caregiver-reported receipt of the second dose of measles–rubella vaccine was 95.9 per cent. For new vaccines, receipt of the second dose of inactivated polio vaccine was 93.1 per cent. Receipt of the typhoid conjugate vaccine, among children aged 9 months or older, was 74.6 per cent (958). Reported receipt of the HPV vaccine, among girls aged 9 to 14 years, was 63 per cent (17). A single composite measure of completion of all vaccines due after 12 months was 89.7 per cent. This composite is not a recognised coverage indicator. It is reported here only to allow comparison with the individual antigens. Completion did not differ significantly across the three districts.

The reported percentage for the HPV vaccine should be read as indicative rather than exact. HPV vaccination in Malawi is delivered mainly through schools rather than through the immunisation contacts from which caregivers were sampled. Receipt was therefore reported at second hand. It could not be verified against the child health passport. The school-based delivery was confirmed by a teacher in Chikwawa, who described vaccine promotion for girls aged 9 to 14 as taking place mainly in schools.

“Yes, especially to children of 9 to 14 years which is mostly done in schools.”

(Teacher, key-informant interview, Chikwawa)

The reasons that caregivers gave for a child not receiving a newer vaccine were recorded. The most common response was that the child was not yet the right age, which reflects children who were not yet due. Once that group was set aside, the leading reason was a lack of awareness of the vaccine, reported by 321 caregivers. Smaller numbers reported that they did not consider the vaccine necessary, that they did not know the schedule, or that the vaccine was unavailable at the facility. Refusal of the vaccine was rarely given as a reason. Fear of side effects was reported by 12 caregivers, partner refusal by two, and religious or cultural belief by one.

A sensitivity analysis compared caregivers whose reports were verified against the child health passport with those who reported from memory. Among the 335 children in the analytic sample with health-passport verification, completion was 93.1 per cent. Among those reported from memory, completion was 87.9 per cent. The verified estimate was therefore slightly higher, which does not suggest that recall inflated the coverage figure.

3.3. Confidence and Community Concerns

Caregiver confidence in the safety of the newer vaccines was high but not universal. Very high confidence was reported by 816 caregivers (69.3 per cent). A further 321 caregivers (27.3 per cent) were only slightly confident. A small group of 40 caregivers (3.4 per cent) were not confident. Trust in the information provided by health workers was almost universal at 99 per cent. Most caregivers, at 94 per cent, believed that vaccines remain important after the first birthday.

Community concerns about the newer vaccines were present in a substantial minority of caregivers. The belief that the HPV vaccine causes infertility was the most frequently reported concern, mentioned by 254 caregivers (22.2 per cent). Concern about side effects was reported by 197 caregivers (17.2 per cent). Discouragement from accepting the newer vaccines had been experienced by 270 caregivers (23 per cent). Among those who had been discouraged, the most common source was a friend, followed by a family member. A stockout that turned the caregiver away had been experienced by 291 caregivers (25.0 per cent). Health workers identified the same pattern. A nurse in Chikwawa named HPV as the vaccine that caregivers most often resisted, and attributed the resistance to misinformation. Table 2 presents these findings.

Table 2. Confidence in the newer vaccines and community concerns (N = 1177).

Measure	Category	N (%)
Confidence in safety	Very confident	816 (69.3)
	Slightly confident	321 (27.3)
	Not confident	40 (3.4)
Received reminder or follow-up communication	Yes	1008 (86)
Reminded or followed up by a health worker	Yes	1063 (91)
Trust health worker information	Yes	1156 (99)
Believe vaccines important after age one	Yes	1098 (94)
Turned away by a stockout	Yes	291 (25.0)
Discouraged from accepting a newer vaccine	Yes	270 (23)
Community concern reported	HPV vaccine causes infertility	254 (22.2)
	Side effects	197 (17.2)
	Too many vaccines	150 (13.1)
	Not safe or not well tested	117 (10.2)
	Causes disability or long-term illness	100 (8.7)
	Causes death	89 (7.8)

Note. Percentages are of respondents with a valid response to each item. Denominators therefore vary slightly below 1177 where data were missing. Concern categories are not mutually exclusive.

The qualitative accounts gave content to the infertility concern. Caregivers described a specific belief that the HPV vaccine damages the reproductive organs. A caregiver in a Kasungu focus group reported the community message in the following way.

“They say it removes the womb so that one should not give birth.”

(Caregiver, focus group discussion, Kasungu)

The concern was often paired with a decision to vaccinate in any case. This pattern is consistent with the high coverage observed in the survey. Another caregiver in the same discussion described her own response.

“You should not go and meet health workers because your children will become infertile, but we just follow the health workers.”

(Caregiver, focus group discussion, Kasungu)

The same belief was expressed in Mangochi. A DCSA there reported a fear that some of the newer vaccines were “contraceptives which are given to children so that they should not give birth in the future.” The concern therefore appeared in the qualitative accounts from Kasungu and Mangochi.

3.4. Factors Associated with Completion

Table 3 presents factors associated with completion of the second-year vaccination schedule, accounting for clustering of children within households using cluster-robust standard errors. Overall, there was limited evidence that socioeconomic characteristics were associated with second-year vaccine completion. After adjustment for other factors, neither household wealth, food insecurity, caregiver literacy, nor district was significantly associated with second-year vaccine completion. Compared with Chikwawa, the odds of completion were higher in Mangochi (AOR = 2.15, 95% CI: 0.82–5.65) and slightly higher in Kasungu (AOR = 1.12, 95% CI: 0.66–1.90), but neither association reached statistical significance.

Table 3. Unadjusted and adjusted associations with completion of second-year and new vaccination (n = 1287 from 1177 households).

Factor	Category	Crude OR (95% CI)	p-Value	Adjusted OR (95% CI)	p-Value
District	Chikwawa	-		-
	Kasungu	0.78 (0.48–1.27)	0.31	1.12 (0.66–1.90)	0.68
	Mangochi	1.95 (0.75–5.05)	0.17	2.15 (0.82–5.65)	0.12
Wealth tertile	Poorest	-		-
	Least poor	0.81 (0.45–1.48)	0.49	0.67 (0.35–1.30)	0.24
	Middle	0.79 (0.43–1.43)	0.43	0.66 (0.36–1.22)	0.18
Food insecurity	Food secure	-		-
	Mild insecure	0.84 (0.26–2.78)	0.78	1.07 (0.34–3.38)	0.91
	Moderately insecure	1.45 (0.56–3.76)	0.44	1.52 (0.58–4.01)	0.39
	Severely insecure	0.84 (0.42–1.68)	0.61	0.72 (0.34–1.52)	0.39
Distance	≤5 km	-		-
	>5 km	0.47 (0.28–0.77)	0.003	0.51 (0.30–0.88)	0.01
Caregiver literacy	Able to read or write	1.21 (0.67–2.19)	0.52	1.20 (0.65–2.22)	0.55
Confidence	Slightly confident	0.74 (0.22–2.48)	0.62	0.62 (0.16–2.38)	0.49
	Very confident	1.55 (0.47–5.12)	0.47	1.29 (0.35–4.75)	0.71
Health worker reminder	Received	3.33 (1.85–5.88)	<0.001	3.03 (1.61–5.88)	<0.001
Stockout	Turned away	0.82 (0.47–1.45)	0.49	0.93 (0.52–1.66)	0.82
Discouragement	Experienced	1.12 (0.65–1.92)	0.68	1.09 (0.61–1.93)	0.77

Note. OR denotes odds ratio. CI denotes confidence interval. The outcome is completion of vaccines due after 12 months. The adjusted model included all listed factors. Standard errors are cluster-robust, accounting for clustering of children within households.

Distance from the health facility remained significantly associated with vaccination completion after accounting for clustering. Children whose caregivers lived more than 5 km from a health facility had approximately half the odds of completing the second-year vaccination schedule compared with those living within 5 km (AOR = 0.51, 95% CI: 0.30–0.88, p = 0.01). This suggests that geographical access to vaccination services may be an important barrier to completing vaccinations, even after accounting for other caregiver and household characteristics.

Receipt of a health-worker reminder was also significantly associated with vaccine completion. Caregivers who reported receiving a reminder had higher odds of reporting completion compared with those who did not report receiving a reminder (AOR = 3.03, 95% CI: 1.61–5.88, p < 0.001). There was no evidence of an independent association between confidence in vaccines, being turned away because of stockouts, or reported discouragement from accepting newer vaccines and second-year vaccine completion. The associations remained non-significant after adjustment for other covariates and accounting for the clustering of children within households.

The qualitative accounts explained how reminders and follow-up operate in practice. Volunteers described a routine of checking the child health passport during household visits. They then returned to the caregivers of children who had missed a dose. A volunteer in Kasungu described the follow-up in the following way.

“During door to door visits we check health passports and know whether he or she has been vaccinated or not.”

(Community volunteer, key-informant interview, Kasungu)

A volunteer in Mangochi described the same register-based routine, in which the village health committee divided the tracing of missed children between its members.

“We check in the register for those who have come to receive vaccine and how many failed to come. So, we follow up on those who failed, because we split the work among us.”

(Community volunteer, key-informant interview, Mangochi)

A caregiver in Chikwawa confirmed the same contact from the other side. She named follow-up from DCSAs as the main reason for completing vaccines after 12 months. Volunteers also reported that the drop-off in demand begins early in the second year.

“Caregivers stop taking vaccines seriously after the age of 9 months.”

(Community volunteer, key-informant interview, Chikwawa)

DCSAs attributed this drop-off to a specific belief among caregivers. A DCSA in Chikwawa described the belief in the following way.

“The belief that when a child reaches 9 months is done with vaccines.”

(DCSA, key-informant interview, Chikwawa)

A facility in-charge in the same district described the same pattern from the service side. This informant reported that caregivers were willing to vaccinate during the first year. Caregivers then became negligent about the doses that fell due after the first birthday. A DCSA in Mangochi described the same drop-off, noting that some caregivers “stop after receiving measles at 9 months.” The pattern was therefore consistent across the three districts.

Two accounts placed the follow-up function under strain. A volunteer in Chikwawa reported that defaulter tracing had weakened for want of resources.

“Yes, they are functional but not as they used to, because of lack of funds.”

(Community volunteer, key-informant interview, Chikwawa)

Volunteers across the districts described shortages of transport and delayed allowances. Volunteers reported that these shortages limited household visits.

The functioning of defaulter tracing varied between facilities within the same district. A DCSA at one facility reported that the system was not functional. The same worker identified fuel for the motorcycle as the constraint on the household visits.

“The availability of a motorcycle has helped us, but the challenge is fuel.”

(DCSA, key-informant interview, Chikwawa)

A DCSA at a second facility in the same district described a system that was working, in which volunteers reminded caregivers of due dates and missed children were traced within days.

“We track them through registers and volunteers. We make sure that a child who has missed vaccines should be vaccinated within the next three days.”

(DCSA, key-informant interview, Chikwawa)

The contrast between a functioning system at one facility and a stalled system at another in the same district suggests that follow-up may depend on local resourcing rather than on uniform national provision.

3.5. Integration of Quantitative and Qualitative Findings

The two components were brought together in a joint display, shown in Table 4. The display sets each survey finding alongside the qualitative evidence that helps to explain it. The reminder result gained a plausible explanation, namely the household visit and the health-passport check. The infertility results gained content and social meaning. The high coverage gained context, because caregivers described vaccinating despite the concerns they had heard.

Table 4. Joint display of quantitative findings and qualitative evidence.

Quantitative Finding	Qualitative Evidence	Integrated Interpretation
Health worker reminder was associated with completion (aOR 3.03)	Volunteers described health-passport checks, door-to-door follow-up, and monthly defaulter tracing. Caregivers named follow-up by DCSAs as their reason for completing later doses.	Active human follow-up may help sustain completion.
Completion did not vary with wealth, food insecurity, or literacy, but did vary by distance	Caregivers across wealth levels described the same reliance on health worker contact and community channels.	No socioeconomic gradient was detected, but distance remained a barrier; the qualitative data could not directly explain this association.
Coverage is high but drops after infancy	Volunteers reported that caregivers stop attending after about 9 months of age.	Declining attendance after nine months may contribute to lower uptake of later doses. Follow-up is most needed after the first year.
Infertility was the most common concern (22.2 per cent)	Caregivers and volunteers described beliefs that the HPV vaccine removes the womb or reduces the population.	A latent demand-side vulnerability sits beneath high coverage and centres on the adolescent vaccine. Infertility concerns were common but rarely led to refusal.
Trust in health worker information was near universal (99 per cent)	Belief was reinforced by radio messages, by the example of other mothers, and by chiefs, churches, and mother groups.	Trusted health workers and community channels are available vehicles for proactive communication. They may help prevent concerns from becoming refusals.
Reminder or follow-up was reported by 86 to 91 per cent of caregivers	Volunteers reported that defaulter tracing had weakened for want of funds, transport, and timely allowances.	Reported contact was high, but volunteers described strain on household tracing. The follow-up function may be fragile and may require protected resourcing.

Note. aOR denotes adjusted odds ratio.

4. Discussion

4.1. Principal Findings

This mixed-methods study of 1177 caregivers across three Malawian districts found that vaccination continues to work well into the second year of life. Coverage of the two routine second-year antigens was high for the second doses of MR and IPV. The completion of all doses due after 12 months reached 89.7%. This performance was largely equitable among the caregivers reached: completion did not vary with household wealth, food insecurity or literacy, despite severe food insecurity in almost two in three households. Distance was the exception. Caregivers living more than 5 km from a facility had about half the odds of completion. The other factor associated with completion was contact with a health worker through a reminder or follow-up, a low-technology function already embedded in the community health system. Confidence in the newer vaccines was high and trust in health workers near-universal, and although a belief that HPV vaccine causes infertility was present in all three districts, it did not translate into refusal. However, coverage of the newest (TCV 74.6%) and off-routine antigens was markedly lower (HPV 63%), and the follow-up function associated with completion was reported to be fragile.

4.2. Interpreting Vaccine Coverage Rates and Persistent Vulnerabilities

Coverage of vaccines targeting young children was uneven. Coverage for routine second-year antigens was high, reaching 95.9% for the second dose of MR and 93.1% for the second dose of IPV. These estimates exceeded the most recent WHO and UNICEF national estimates of approximately 77% [23]. Although IPV itself is not new in Malawi, the second dose was introduced less than a year before this survey; the high coverage of a new second dose is consistent with other evidence that also found high coverage soon after introduction [6]. By contrast, coverage of TCV, which is given earlier in childhood at nine months of age, was substantially lower. This difference may reflect both the newer status of TCV and the way caregiver awareness and follow-up are organised around later routine contacts. The qualitative data suggest that active household follow-up and defaulter tracing may help sustain coverage into the second year of life, particularly for vaccines embedded in established follow-up systems. HPV vaccination should be interpreted separately from the early-childhood and second-year vaccines because it targets older girls and is delivered mainly through school-based campaigns rather than routinely at health facilities.

The high MR and IPV estimates should also be interpreted in light of the study design and delivery context. Our estimates are caregiver-reported and come from three purposively selected districts, whereas the WHO and UNICEF comparators are administrative and modelled national estimates. This difference in methods and geography may have produced higher coverage estimates than would be expected in a nationally representative estimate. Malawi also conducted repeated MR and oral polio campaigns during the period in which the sampled children were born and became eligible for these doses, e.g., MR campaigns in Mangochi and Kasungu in June 2025 [24,25]. Some reported coverage may therefore reflect campaign delivery rather than routine second-year services, warranting caution, particularly for MR. Nonetheless, the qualitative accounts offer a complementary explanation beyond campaign delivery: caregivers, volunteers, and health workers described active household follow-up, health-passport checks and defaulter tracing as mechanisms for identifying children who had missed doses. These strategies may have contributed to the high reported coverage, while the lower uptake of TCV and HPV suggests that vaccines delivered in the first year of life or outside of established pathways remain more vulnerable to missed opportunities.

Vaccine uptake completion did not vary with household wealth, food insecurity or caregiver literacy, indicating no socioeconomic gradient among the caregivers surveyed. This pattern departs from much of the regional literature: studies of second-year and adolescent vaccination in sub-Saharan Africa have repeatedly found that wealth, maternal education and distance predict uptake, with drop-out concentrated among the poorest households [13,23]. Our distance finding, by contrast, is consistent with that literature. We found no wealth gradient in a sample where 64% of households were severely food insecure. This may reflect features of the EPI programme that equalise access since immunisation is free, and outreach delivery reduces the transport and time costs that typically disadvantage the poorest households. Earlier Malawian evidence similarly concluded that the EPI serves rich and poor alike, an outcome attributed to outreach clinics and community health workers [26]. Outreach has been shown elsewhere to reduce or eliminate socioeconomic differentials in vaccine receipt [27].

Two further explanations are consistent with our data. First, completion was high and near-uniform at 89.7%, compressing the room for any gradient to appear. This supports earlier evidence that wealth-related inequality in vaccination narrows as overall coverage rises [27]. Second, follow-up reached caregivers across all wealth tertiles, so active human contact may have substituted for the socioeconomic advantage that ordinarily drives gradients. However, as we did not examine whether reminder receipt itself varied by wealth, this remains an interpretation rather than a demonstrated mechanism. The equity observed here is therefore best read as equity among service users: an encouraging finding for those who reach services, but one that cannot speak to caregivers who never attend, who are absent from the sample by design and are typically poorer.

Receipt of a health worker reminder was one of two factors associated with completion. In the adjusted model, reminded caregivers had more than three times the odds of completing the schedule, and the association held after accounting for clustering of children within households. Because completion was common, the odds ratio overstates the size of the effect. Reminder and follow-up were themselves common, reported by most caregivers. The qualitative accounts show how this contact works in practice. Volunteers described checking the child health passport during household visits and returning to caregivers whose children had missed a dose. In some areas the defaulter tracing was shared among volunteers to ensure that missed children were vaccinated within a few days, and a caregiver in Chikwawa mentioned this follow-up from DCSAs as her own reason for completing the later doses. The result is consistent with the wider evidence that reminder and recall improve uptake, where a Cochrane review reported an average gain of about eight percentage points and found telephone reminders the most effective type [28]. It also echoes reports from elsewhere in the region that home visits and defaulter tracing by community health workers improve schedule completion [29]. The distinctive feature in this setting is that the function is carried by people rather than by digital tools.

The same accounts describe this follow-up function as fragile and unevenly resourced. This fragility sits alongside high reported contact. In the survey, 86 per cent of caregivers reported a reminder and 91 per cent reported follow-up by a health worker. These findings are not necessarily in conflict. Reminders may often be given at facility or outreach sessions rather than through home visits. The strain on household tracing may also be recent. The survey did not record the channel or timing of reminders, so this cannot be tested. One volunteer in Chikwawa reported that defaulter tracing was functional but limited by funding constraints. Volunteers across the districts described shortages of transport and delayed allowances that limited household visits. The strain differed even within a single district. At one facility the system had stalled on a practical constraint, a worker noting fuel challenges, despite the availability of a motorcycle. At another facility in the same district the tracing ran to a clear standard, with missed children vaccinated in less than a week. This contrast suggests that follow-up may depend on local resourcing rather than on uniform national provision. It also mirrors reports from other parts of Malawi and neighbouring countries that reductions in partner funding weaken outreach, supervision and training [30]. Where the function weakens, the children who are due for later doses are the first to be missed.

4.3. Confidence in Vaccines and Community Concerns

Confidence in the newer vaccines was high but not universal. The caregivers’ trust in the information given by health workers was almost universal, and most of them believed that vaccines remain important after the first birthday. Beneath this confidence sat a specific concern. More than one in five caregivers reported a community belief that the HPV vaccine causes infertility, and health workers named HPV as the vaccine most often resisted. The qualitative accounts in Kasungu gave the belief its content, with caregivers linking the vaccine to birth control practices, and volunteers linking it to population control. The same belief appeared in Mangochi, where a DCSA reported a fear that some newer vaccines were contraceptives given to prevent future childbearing. Almost a quarter of caregivers had been actively discouraged from taking a newer vaccine, most often by a friend. This pattern matches evidence from across sub-Saharan Africa, where fear of infertility is among the most salient drivers of HPV hesitancy [31].

4.4. Concern Without Refusal: The Possible Role of Health Worker Trust

The community concerns did not translate into refusal of vaccines. Refusal was rare in the survey, given by only 12 caregivers due to fear of side effects, two due to partner refusal and one due to religious or cultural belief; caregivers described vaccinating in spite of the rumours they had heard. One caregiver in Kasungu explained that although people warned her that the vaccine would cause infertility in her children, she and others opted to trust the health workers. This gap between a held concern and the decision to vaccinate reflects the pattern reported in comparable studies of caregivers, where motivation to vaccinate coexists with social and practical barriers [32,33]. In this setting, the near-universal trust in health workers may have carried caregivers past the rumour. Two cautions temper the reassurance. This pattern may depend on trust, which is the same asset that the fragility of the follow-up system puts at risk. The outcome also captured the early childhood doses more fully than the school-delivered HPV dose, so the effect of the belief on adolescent vaccination may be underestimated rather than absent. The concern is therefore best read as a latent vulnerability that could reduce HPV uptake as those programmes expand.

The infertility narrative should be understood not simply as a deficit in knowledge, but as a culturally meaningful expression of uncertainty about a vaccine introduced for adolescent girls and linked to future reproductive health. In settings where fertility and future childbearing carry strong social significance, claims that vaccination could impair reproduction may be especially persuasive. Such concerns can also draw strength from broader historical experiences of externally supported health programmes, rapid vaccine introductions, and limited opportunities for communities to ask questions before implementation. This further indicates that hesitancy can be socially produced and reinforced beyond individual attitudes. In this study, such concerns rarely became refusal, suggesting that trust in health workers may offset uncertainty. Early, respectful dialogue through trusted health workers, teachers, community leaders, and caregivers may therefore help prevent hesitancy from reducing uptake.

4.5. Implications for Programme Delivery

The study findings point to some practical programme priorities. First, stockouts should be treated as missed opportunities even where they do not appear to reduce final completion. Caregivers who are turned away must make additional journeys to be vaccinated, and repeated futile visits risk eroding confidence in the service. Stronger vaccine forecasting, routine stock monitoring, inter-facility redistribution, and clear communication with caregivers when vaccines are unavailable would help ensure that a return visit reliably ends in vaccination rather than another deferral.

Second, follow-up should begin before the second year of life, and the nine-month contact is the critical point of intervention. Because MR1, TCV and IPV2 are all delivered at this single visit, caregivers may reasonably assume the schedule is complete once these doses have been given. The visit should therefore be used deliberately to explain that MR2 remains due in the second year, to verify entries in the health passport, and to flag children at risk of defaulting before they are lost to the system. Additionally, every contact with caregivers should be used as an opportunity to educate them about the HPV vaccine, which, despite not being due for the child, might be relevant for older siblings or relatives.

Third, the sustainability of household follow-up activities associated with completion requires protected, predictable resourcing: fuel, transport, registers, supervision, and volunteer allowances paid on time. Where these inputs depend on discretionary or intermittent funding, defaulter tracing becomes the first activity to lapse. Sustaining high coverage beyond infancy will therefore depend not only on caregiver demand, but on reliable vaccine supply and a funded community follow-up system capable of finding and returning children who miss scheduled doses.

4.6. Strengths and Limitations

The study’s strengths include a large sample across three districts, socioeconomic position measured in two ways, a focus on the under-studied second year of life, and the integration of a coverage survey with provider and caregiver accounts in a joint display, which allowed the patterns to be explained rather than only described. A sensitivity analysis strengthens confidence in the headline estimate: completion among health-passport-verified reports was higher than among reports from memory, indicating that recall did not inflate coverage.

Several limitations qualify the findings. Most vaccination reports were provided by caregivers rather than verified against health records; consequently, the coverage estimates may be affected by recall error and are not directly comparable with administrative figures. The school-delivered HPV doses were particularly difficult to verify; therefore, it was not possible to determine whether participants had received one or both doses. This limitation precluded analysis of factors associated with completion of the two-dose HPV vaccination schedule. The high, near-uniform completion outcome also reduced statistical power to detect associations, meaning that null findings for the socioeconomic factors indicate no detectable gradient in this sample rather than evidence that no gradient exists. The design was cross-sectional, so the association between reminders and completion cannot establish causality and may reflect targeted follow-up of caregivers whose children had already missed doses. Confidence and community concerns were self-reported and may have been influenced by social desirability. The study did not collect data on the relationship of the caregiver to the child; therefore, this potentially relevant covariate could not be included in the regression analysis to examine whether vaccine uptake or hesitancy differed between mothers and other female caregivers.

The three study districts were selected to capture contextual variation but were not intended to provide nationally representative estimates. Most importantly, recruitment was linked to health-facility catchment areas and included caregivers who had attended immunisation services. Caregivers who never attended services, including those who may face the greatest geographical, socioeconomic, informational, or trust-related barriers, were therefore under-represented. This selection may have contributed to the high coverage estimates and the absence of pronounced socioeconomic gradients, and the findings should consequently be interpreted as describing equity among caregivers reached by the immunisation system rather than equity across the entire eligible population. Nonetheless, the observed importance of distance, health-worker follow-up, and concerns about newer vaccines may be transferable to other Malawian districts with similar rural populations and community-based immunisation systems. These mechanisms may also be relevant in other low-resource countries that rely on community health workers and outreach services, although their applicability will vary based on vaccine schedules, delivery platforms, health-system capacity, and local social contexts.

Future research should use population-based sampling and purposive strategies to identify non-attenders, zero-dose children, out-of-school girls, mobile households, and communities distant from fixed or outreach services. Longitudinal or prospective studies could establish the temporal relationship between reminders and vaccine completion; implementation studies or cluster-randomised trials could compare reminder and recall approaches, including household visits, register-based tracing, mobile-phone communication, and community-led follow-up.

Research should also assess how reminder exposure and effectiveness vary by wealth, distance, gender, district, and service-delivery platform, and should incorporate routine records or electronic registries to strengthen vaccination-status verification. Qualitative work focused specifically on non-attenders would clarify whether their barriers differ from those reported by service users and would support the design of interventions that extend beyond populations already connected to immunisation services.

5. Conclusions

Second-year immunisation in these three districts of Malawi was high, equitable across wealth, food security and literacy among the caregivers reached, and associated with a low-technology function such as human reminders and follow-up delivered by community health workers. Confidence was high and trust in health workers strong enough that a widespread infertility concern did not translate into refusal. The principal risks were identifiable: distance over 5 km reduced completion; the newest antigens, delivered outside the follow-up routine, lagged; and the follow-up function itself was fragile and unevenly resourced. The central message is therefore an encouraging one with a clear condition attached. A trusted, human follow-up system may help carry vaccination through the second year of life even in a very poor setting, provided that system is protected, and provided proactive communication reaches caregivers before latent concern and off-routine delivery undermine what has been achieved.