Predictors of malaria vaccine uptake among children 6–24 months in the Kassena Nankana Municipality in the Upper East Region of Ghana

Community acceptance of a novel malaria intervention, Attractive Targeted Sugar Baits, in the Zambia phase III trial

BACKGROUND

Community acceptance is an important criterion to assess in community trials, particularly for new tools that require high coverage and use by a target population. Installed on exterior walls of household structures, the attractive targeted sugar bait (ATSB) is a new vector control tool designed to attract and kill mosquitoes. ATSBs were evaluated in Western Zambia during a two-year cluster randomized controlled trial to assess the efficacy of ATSBs in reducing malaria transmission. Community acceptance of ATSBs was critical for successful trial implementation.

METHODS

A community engagement strategy outlined activities and key messages to promote acceptance. Annual cross-sectional surveys, conducted during the peak transmission period, assessed households for presence of ATSBs as well as perceived benefits, concerns, and willingness to use ATSBs. Sixteen focus group discussions and 16 in-depth interviews, conducted at the end of each ATSB station deployment period, obtained a range of perceptions and household experiences with ATSB stations, as well as ITN use in the context of ATSB deployment.

RESULTS

Methods used during the study to promote acceptance and continued use of ATSBs were effective in achieving greater than 90% coverage, a high (greater than 70%) level of perceived benefits, and fewer than 10% of households reporting safety concerns. Common facilitators of acceptance included the desire for protection against malaria and reduction of mosquitoes, trust in health initiatives, and understanding of the product. Common barriers to acceptance included misconceptions of product impact on mosquitoes, continued cases of malaria, association with satanism, and damage to household structures.

DISCUSSION

Future use of the ATSB intervention will likely require activities that foster community acceptance before, during, and after the intervention is introduced. Additional research may be needed to understand the impact of different levels of community engagement on ATSB station coverage, ATSB station perception, and ITN use.

CONCLUSION

There was high acceptance of ATSB stations during the trial in Western Zambia. Continuous and intense community engagement efforts contributed to sustained ATSB coverage and trust in the product. Acceptance of ATSBs during programmatic delivery requires further research.

Malaria vaccination in Africa: A mini-review of challenges and opportunities

Malaria remains an endemic public health concern in Africa, significantly contributing to morbidity and mortality rates. The inadequacies of traditional prevention measures, like integrated vector management and antimalarial drugs, have spurred efforts to strengthen the development and deployment of malaria vaccines. In addition to existing interventions like insecticide-treated bed nets and artemisinin-based combination therapies, malaria vaccine introduction and implementation in Africa could drastically reduce the disease burden and hasten steps toward malaria elimination. The malaria vaccine rollout is imminent as optimistic results from final clinical trials are anticipated. Thus, determining potential hurdles to malaria vaccine delivery and uptake in malaria-endemic regions of sub-Saharan Africa will enhance decisions and policymakers' preparedness to facilitate efficient and equitable vaccine delivery. A multisectoral approach is recommended to increase funding and resources, active community engagement and participation, and the involvement of healthcare providers.

Hesitancy towards R21/Matrix-M malaria vaccine among Ghanaian parents and attitudes towards immunizing non-eligible children: a cross-sectional survey

BACKGROUND

The newly developed malaria vaccine called "R21/Matrix-M malaria vaccine" showed a high safety and efficacy level, and Ghana is the first country to approve this new vaccine. The present study aimed to evaluate the rate of vaccine hesitancy (VH) towards the newly developed malaria vaccine among parents who currently have children who are not eligible for the vaccine but may be eligible in the near future. Additionally, the study aimed to identify the factors that could potentially influence VH.

METHODS

A cross-sectional survey using both online-based questionnaires and face-to-face interviews was conducted in Ghana from June to August 2023. The survey specifically targeted parents of ineligible children for vaccination, including those aged less than 5 months or between 3 and 12 years. The Parent Attitudes about Childhood Vaccination (PACV) scale was used to assess parental VH.

RESULTS

A total of 765 people participated in this study. Their median age was 36.0 years with an interquartile range of 31.0-41.0 years, 67.7% were females, 41.8% completed their tertiary education, 63.3% were married, 81.6% worked in non-healthcare sectors, and 59.7% reported that their monthly income was insufficient. About one-third (34.5%) of the parents were hesitant to give their children the R21/Matrix-M malaria vaccine. The following predictors were associated with VH: working in the healthcare sector (adjusted odds ratio (AOR) = 0.50; 95% confidence interval (CI) 0.30-0.80; p = 0.005), having the other parent working in the healthcare sector (AOR = 0.54; 95% CI 0.30-0.94; p = 0.034), and not taking scheduled routine vaccinations (AOR = 1.90; 95% CI 1.27-2.84; p = 0.002).

CONCLUSIONS

Addressing VH is crucial for optimizing R21/Matrix-M vaccine coverage in Ghana's malaria control strategy. By tackling VH issues, Ghana can effectively safeguard children's health in malaria-prone areas.

Policy uptake and implementation of the RTS,S/AS01 malaria vaccine in sub-Saharan African countries: status 2 years following the WHO recommendation

In October 2021, the WHO recommended the world's first malaria vaccine-RTS,S/AS01-to prevent malaria in children living in areas with moderate-to-high transmission in sub-Saharan Africa (SSA). A second malaria vaccine, R21/Matrix-M, was recommended for use in October 2023 and added to the WHO list of prequalified vaccines in December 2023. This study analysis assessed the country status of implementation and delivery strategies for RTS,S/AS01 by searching websites for national malaria policies, guidelines and related documents. Direct contact with individuals working in malaria programmes was made to obtain documents not publicly available. 10 countries had documents with information relating to malaria vaccine implementation, 7 referencing RTS,S/AS01 and 3 (Burkina Faso, Kenya and Nigeria) referencing RTS,S/AS01 and R21/Matrix-M. Five other countries reported plans for malaria vaccine roll-out without specifying which vaccine. Ghana, Kenya and Malawi, which piloted RTS,S/AS01, have now integrated the vaccine into routine immunisation services. Cameroon and Burkina Faso are the first countries outside the pilot countries to incorporate the vaccine into national immunisation services. Uganda plans a phased RTS,S/AS01 introduction, while Guinea plans to first pilot RTS,S/AS01 in five districts. The RTS,S/AS01 schedule varied by country, with the first dose administered at 5 or 6 months in all countries but the fourth dose at either 18, 22 or 24 months. SSA countries have shown widespread interest in rolling out the malaria vaccine, the Global Alliance for Vaccines and Immunization having approved financial support for 20 of 30 countries which applied as of March 2024. Limited availability of RTS,S/AS01 means that some approved countries will not receive the required doses. Vaccine availability and equity must be addressed even as R21/Matrix-M becomes available.

Willingness to accept malaria vaccines amongst women presenting at outpatient and immunization clinics in Enugu state, Southeast Nigeria

BACKGROUND

There are giant steps taken in the introduction of the novel malaria vaccine poised towards reducing mortality and morbidity associated with malaria.

OBJECTIVES

This study aimed to determine the knowledge of malaria vaccine and factors militating against willingness to accept the vaccine among mothers presenting in nine hospitals in Enugu metropolis.

METHODS

This was a cross-sectional study carried out among 491 mothers who presented with their children in nine hospitals in Enugu metropolis, South-East Nigeria. A pre-tested and interviewer-administered questionnaire was used in this study.

RESULTS

A majority of the respondents, 72.1% were aware of malaria vaccine. A majority of the respondents, 83.1% were willing to receive malaria vaccine. Similarly, a majority of the mothers, 92.9%, were willing to vaccinate baby with the malaria vaccine, while 81.1% were willing to vaccinate self and baby with the malaria vaccine. The subjects who belong to the low socio-economic class were five times less likely to vaccinate self and baby with malaria vaccine when compared with those who were in the high socio-economic class (AOR = 0.2, 95% CI 0.1-0.5). Mothers who had good knowledge of malaria vaccination were 3.3 times more likely to vaccinate self and baby with malaria vaccine when compared with those who had poor knowledge of malaria vaccination (AOR = 3.3, 95% CI 1-6-6.8).

CONCLUSION

Although the study documented a high vaccine acceptance among the mothers, there exists a poor knowledge of the malaria vaccine among them.

Willingness to accept malaria vaccines amongst women presenting at outpatient and immunization clinics in Enugu state, Southeast Nigeria

Background

There are giant steps taken in the introduction of the novel malaria vaccine poised towards reducing mortality and morbidity associated with malaria.

Objectives

This study aimed to determine the knowledge of malaria vaccine and factors militating against willingness to accept the vaccine among mothers presenting in nine hospitals in Enugu metropolis.

Methods

This was a cross-sectional study carried out among 491 mothers who presented with their children in nine hospitals in Enugu metropolis, South-East Nigeria. A pre-tested and interviewer-administered questionnaire was used in this study.

Results

A majority of the respondents, 72.1% were aware of malaria vaccine. A majority of the respondents, 83.1% were willing to receive malaria vaccine. Similarly, a majority of the mothers, 92.9%, were willing to vaccinate baby with the malaria vaccine, while 81.1% were willing to vaccinate self and baby with the malaria vaccine. The subjects who belong to the low socio-economic class were five times less likely to vaccinate self and baby with malaria vaccine when compared with those who were in the high socio-economic class (AOR = 0.2, 95% CI 0.1–0.5). Mothers who had good knowledge of malaria vaccination were 3.3 times more likely to vaccinate self and baby with malaria vaccine when compared with those who had poor knowledge of malaria vaccination (AOR = 3.3, 95% CI 1–6–6.8).

Conclusion

Although the study documented a high vaccine acceptance among the mothers, there exists a poor knowledge of the malaria vaccine among them.

Factors associated with malaria vaccine uptake in Nsanje district, Malawi

BACKGROUND

Malaria remains a significant global health burden affecting millions of people, children under 5 years and pregnant women being most vulnerable. In 2019, the World Health Organization (WHO) endorsed the introduction of RTS,S/AS01 malaria vaccine as Phase IV implementation evaluation in three countries: Malawi, Kenya and Ghana. Acceptability and factors influencing vaccination coverage in implementing areas is relatively unknown. In Malawi, only 60% of children were fully immunized with malaria vaccine in Nsanje district in 2021, which is below 80% WHO target. This study aimed at exploring factors influencing uptake of malaria vaccine and identify approaches to increase vaccination.

METHODS

In a cross-sectional study conducted in April-May, 2023, 410 mothers/caregivers with children aged 24-36 months were selected by stratified random sampling and interviewed using a structured questionnaire. Vaccination data was collected from health passports, for those without health passports, data was collected using recall history. Regression analyses were used to test association between independent variables and full uptake of malaria vaccine.

RESULTS

Uptake of malaria vaccine was 90.5% for dose 1, but reduced to 87.6%, 69.5% and 41.2% for dose 2, 3, and 4 respectively. Children of caregivers with secondary or upper education and those who attended antenatal clinic four times or more had increased odds of full uptake of malaria vaccine [OR: 2.43, 95%CI 1.08-6.51 and OR: 1.89, 95%CI 1.18-3.02], respectively. Children who ever suffered side-effects following immunization and those who travelled long distances to reach the vaccination centre had reduced odds of full uptake of malaria vaccine [OR: 0.35, 95%CI 0.06-0.25 and OR: 0.30, 95%CI 0.03-0.39] respectively. Only 17% (n = 65) of mothers/caregivers knew the correct schedule for vaccination and 38.5% (n = 158) knew the correct number of doses a child was to receive.

CONCLUSION

Only RTS,S dose 1 and 2 uptake met WHO coverage targets. Mothers/caregivers had low level of information regarding malaria vaccine, especially on numbers of doses to be received and dosing schedule. The primary modifiable factor influencing vaccine uptake was mother/caregiver knowledge about the vaccine. Thus, to increase the uptake Nsanje District Health Directorate should strengthen communities' education about malaria vaccine. Programmes to strengthen mother/caregiver knowledge should be included in scale-up of the vaccine in Malawi and across sub-Saharan Africa.

Integration of the RTS,S/AS01 malaria vaccine into the Essential Programme on Immunisation in western Kenya: a qualitative longitudinal study from the health system perspective

BACKGROUND

Malaria accounts for over half a million child deaths annually. WHO recommends RTS,S/AS01 to prevent malaria in children living in moderate-to-high malaria transmission regions. We conducted a qualitative longitudinal study to investigate the contextual and dynamic factors shaping vaccine delivery and uptake during a pilot introduction in western Kenya.

METHODS

The study was conducted between Oct 3, 2019, and Mar 24, 2022. We conducted participant and non-participant observations and in-depth interviews with health-care providers, health managers, and national policymakers at three timepoints using an iterative approach and observations of practices and processes of malaria vaccine delivery. Transcripts were coded by content analysis using the consolidated framework for implementation research, to which emerging themes were added deductively and categorised into challenges and opportunities.

FINDINGS

We conducted 112 in-depth interviews with 60 participants (25 health-care providers, 27 managers, and eight policy makers). Health-care providers highlighted limitations in RTS,S/AS01 integration into routine immunisation services due to the concurrent pilot evaluation and temporary adaptations for health reporting. Initial challenges related to the complexity of the four-dose schedule (up to 24-months); however, self-efficacy increased over time as the health-care providers gained experience in vaccine delivery. Low uptake of the fourth dose remained a challenge. Health managers cited insufficient trained immunisation staff and inadequate funding for supervision. Confidence in the vaccine increased among all participant groups owing to reductions in malaria frequency and severity.

INTERPRETATION

Integration of RTS,S/AS01 into immunisation services in western Kenya presented substantial operational challenges most of which were overcome in the first 2 years, providing important lessons for other countries. Programme expansion is feasible with intensive staff training and retention, enhanced supervision, and defaulter-tracing to ensure uptake of all doses.

FUNDING

PATH via World Health Organization; Gavi, the Vaccine Alliance; The Global Fund; and Unitaid.

Malaria prevention in children: an update

PURPOSE OF REVIEW

Malaria cases and deaths decreased from 2000 to 2015 but remain increased since 2019. Several new developments and strategies could help reverse this trend. The purpose of this review is to discuss new World Health Organization (WHO) guidelines and recent research on malaria prevention in children.

RECENT FINDINGS

Fifteen countries have now rolled out seasonal malaria chemoprophylaxis (SMC) in children at highest risk for severe malaria, and new WHO recommendations provide more flexibility for SMC implementation in terms of target age groups, geographic region, and number of cycles. Recent studies confirm that malaria burden in school aged children, and their contribution to transmission, is high. New guidelines permit expanded chemoprevention options for these children. Two vaccines have been approved for use in malaria endemic countries, RTS,S/AS01 E and R21/Matrix-M. Additionally, pyrethroid-chlorfenapyr bed nets are being deployed to combat resistant mosquitoes.

SUMMARY

While challenges remain in malaria control towards elimination, new guidelines and recently approved vaccines offer hope. Monitoring for continued vaccine and chemoprevention effectiveness, and for possible epidemiologic shifts in severe malaria presentation and deaths as additional prevention efforts roll out will be paramount.

Assessing the Implementation Determinants of Pilot Malaria Vaccination Programs in Ghana, Kenya, and Malawi through a Complexity Lens: A Rapid Review Using a Consolidated Framework for Implementation Research

In 2019, national immunization programs in Ghana, Kenya, and Malawi commenced the implementation of RTS,S/AS01 vaccination in large-scale pilot schemes. Understanding the implementation context of this malaria vaccination in the pilot countries can provide useful insights for enhancing implementation outcomes in new countries. There has not yet been a proper synthesis of the implementation determinants of malaria vaccination programs. A rapid review was conducted to identify the implementation determinants of the pilot malaria vaccination programs in Ghana, Kenya, and Malawi, and describe the mechanism by which these determinants interact with each other. A literature search was conducted in November 2023 in PubMed and Google Scholar to identify those studies that described the factors affecting malaria vaccine implementation in Ghana, Kenya, and Malawi. Thirteen studies conducted between 2021 and 2023 were included. A total of 62 implementation determinants of malaria vaccination across all five domains of the consolidated framework for implementation research (CFIR) were identified. A causal loop diagram showed that these factors are interconnected and interrelated, identifying nine reinforcing loops and two balancing loops. As additional countries in Africa prepare for a malaria vaccine roll-out, it is pertinent to ensure that they have access to adequate information about the implementation context of countries that are already implementing malaria vaccination programs so that they understand the potential barriers and facilitators. This information can be used to inform context-specific systems enhancement to maximize implementation success. Going forward, primary implementation studies that incorporate the causal loop diagram should be integrated into the malaria vaccine implementation program to enable immunization program managers and other key stakeholders to identify and respond to emerging implementation barriers in a timely and systematic manner, to improve overall implementation performance.

A. Pienaah C, Luginaah I. Child malaria vaccine uptake in Ghana: Factors influencing parents' willingness to allow vaccination of their children under five (5) years

BACKGROUND

Malaria is a substantial health burden in Ghana, particularly among children. Despite the availability of malaria vaccines, uptake remains low. Notwithstanding, there is a paucity of nationally representative studies on the factors driving hesitance towards the new malaria vaccine. In response, this study, guided by the Theory of Planned Behaviors (TPB), seeks to understand the determinants of child malaria vaccine uptake in Ghana to inform strategies for improving coverage.

MATERIALS AND METHODS

We employed multiple regression model to examine the association between maternal awareness, socioeconomic status, ethnicity, geographical location, and vaccine uptake using data from the 2019 Ghana Malaria Indicator Survey (MIS).

RESULTS

Maternal awareness of vaccine (OR = 2.200; P<0.01) significantly predicted higher likelihood of vaccine uptake. Household wealth was associated with child vaccination as parents in middle-income households (OR = 9.342; P<0.01), and those in poorest households (OR = 9.409; P<0.05) recorded higher likelihood of allowing their children to be vaccinated. With regards to ethnicity, parents from the Mande ethnic group (OR = 0.106; P<0.05) were less likely to allow their children to be vaccinated when compared to parents from the Akan ethnic group. Knowing that malaria is covered by National Health Insurance (OR = 2.407; P<0.05) was associated with higher likelihood of allowing child vaccination compared to not knowing. More so, geographical variations were observed as parents who lived in rural areas (OR = 0.254; P<0.05) were significantly less likely to allow vaccination of their children compared to those in urban areas.

CONCLUSIONS

Enhancing awareness through education campaigns can improve child malaria vaccine coverage. Observing socioeconomic disparities in uptake and ensuring equitable access to vaccines are vital. Tailored strategies considering ethnic background and geographical location, can as well enhance acceptance of the vaccine. This study provides valuable insights for developing effective strategies to reduce the burden of malaria in children and improve coverage of uptake. This study underscores the need to improve parental awareness and the relevance of the vaccine in preventing child mortality.

Caregiver acceptance of malaria vaccination for children under 5 years of age and associated factors: cross-sectional household survey, Guinea and Sierra Leone, 2022

BACKGROUND

Malaria is a leading cause of death and reduced life span in Guinea and Sierra Leone, where plans for rolling out the malaria vaccine for children are being made. There is little evidence about caregiver acceptance rates to guide roll-out policies. To inform future vaccine implementation planning, this analysis aimed to assess potential malaria vaccine acceptance by caregivers and identify factors associated with acceptance in Guinea and Sierra Leone.

METHODS

A cross-sectional household survey using lot quality assurance sampling was conducted in three regions per country between May 2022 and August 2022. The first survey respondent in each household provided sociodemographic information. A household member responsible for childcare shared their likelihood of accepting a malaria vaccine for their children under 5 years and details about children's health. The prevalence of caregiver vaccine acceptance was calculated and associated factors were explored using multivariable logistic regression modelling calculating adjusted odds ratios (aOR) with 95% confidence intervals (CI).

RESULTS

Caregivers in 76% of 702 sampled households in Guinea and 81% of 575 households in Sierra Leone were accepting of a potential vaccine for their children. In both countries, acceptance was lower in remote areas than in urban areas (Guinea: aOR 0.22 [95%CI 0.09-0.50], Sierra Leone: 0.17 [0.06-0.47]). In Guinea, acceptance was lower among caregivers living in the richest households compared to the poorest households (0.10 [0.04-0.24]), among those whose children were tested for malaria when febrile (0.54 [0.34-0.85]) and in households adopting more preventative measures against malaria (0.39 [0.25-0.62]). Better knowledge of the cause of malaria infection was associated with increased acceptance (3.46 [1.01-11.87]). In Sierra Leone, vaccine acceptance was higher among caregivers living in households where the first respondent had higher levels of education as compared to lower levels (2.32 [1.05-5.11]).

CONCLUSION

In both countries, malaria vaccine acceptance seems promising for future vaccine roll-out programmes. Policy makers might consider regional differences, sociodemographic factors, and levels of knowledge about malaria for optimization of implementation strategies. Raising awareness about the benefits of comprehensive malaria control efforts, including vaccination and other preventive measures, requires attention in upcoming campaigns.

RTS,S/AS01E vaccine defaults in Ghana: a qualitative exploration of the perspectives of defaulters and frontline health service providers

BACKGROUND

While Ghana has a good track record in the Expanded Programme on Immunization, there are substantial challenges with regards to subsequent vaccinations, particularly after the first year of life of the child. Given that the last dose of the RTS, S/AS01E vaccine against malaria is administered at 24 months, there is a high likelihood of default. Hence, it is imperative to understand the dynamics and reasons for the defaults to enable the development of effective implementation strategies. This study explored why caregivers default on the RTS, S/AS01E vaccine from the perspective of health service providers and caregivers.

METHODS

This study employed an exploratory, descriptive approach. Using a purposive sampling technique, caregivers who defaulted and health service providers directly involved in the planning and delivery of the RTS, S/AS01E vaccine at the district level were recruited. A total of five health service providers and 30 mothers (six per FGD) participated in this study. Data analysis was done using NVivo-12 following Collaizi's thematic framework for qualitative analysis. The study relies on the Standards for Reporting Qualitative Research.

RESULTS

Reasons for defaulting included the overlap of timing of the last dose and the child starting school, disrespectful attitudes of some health service providers, concerns about adverse side effects and discomforts, travel out of the implementing district, the perception that the vaccines are too many, and lack of support from partners.

CONCLUSION

To reduce the occurrence of defaulting on the RTS, S/AS01E vaccine programme, stakeholders must reconsider the timing of the last dose of the vaccine. The schedule of the RTS, S/AS01E vaccine should be aligned with the established EPI schedule of Ghana. This will significantly limit the potential of defaults, particularly for the last dose. Also, the findings from this study underscore a need to encourage male partner involvement in the RTS, S/AS01E vaccine programme. Health promotion programmes could be implemented to raise caregivers' awareness of potential adverse reactions and discomforts-this is necessary to prepare the caregiver for the vaccine process psychologically.

Caregivers' perception and acceptance of malaria vaccine for Children

BACKGROUND

Malaria is a disease of public health concern and in endemic areas, pregnant women and children under-five years are vulnerable to the disease. The introduction of the pilot program of a malaria vaccine for children under-five years in Ghana is an intervention to further reduce the burden of the disease. However, the availability of the vaccine does not necessarily mean it will be accepted by the public. This is why the perceptions and acceptance of the vaccine among mothers of these children are worth exploring.

METHOD

A descriptive qualitative study, with the aid of a semi-structured interview guide, was utilized in collecting data from ten (10) purposively sampled mothers whose children were taking the malaria vaccine in a municipality in Ghana. Written informed consent was obtained from all participants. The audiotaped interviews were transcribed verbatim and inductively analyzed into themes describing their perceptions and acceptance.

RESULTS

Participants were aged between 22 and 40 years with eight (8) of them married. Three themes emerged from the study. "Awareness of malaria and the malaria vaccine" (1), "Insight into the malaria vaccine" (2), where participants communicated the beliefs and judgments formed on the vaccine, its benefits, and the need for vaccinating their children. With the third theme "Reaction to vaccine" (3), participants communicated their motivation to vaccinate their children and their concerns about the administration of the vaccine.

CONCLUSION

The caregivers had positive perceptions about the malaria vaccine for children, with fewer hospital admissions and saving money as some benefits. Healthworkers played a significant role in influencing the acceptance of the vaccine. However, the fear of the unknown concerning the side effects of the vaccine serve as a possible barrier to recommending the vaccine to other caregivers. Health education must also address the fears of caregivers in order to enhance recommending the malaria vaccine to other caregivers and promote uptake of the vaccination.

Community Barriers, Enablers, and Normative Embedding of Second Year of Life Vaccination in Ghana: A Qualitative Study

INTRODUCTION

Coverage rates for second year of life (2YL) vaccination still lag behind infant vaccination in most settings. We conducted a qualitative baseline study of community barriers and enablers to acceptance of 2YL vaccines in Ghana 4 years after introducing the second dose of the measles-containing vaccine.

METHODS

We conducted 26 focus group discussions in 2016 with men and women caregivers from mixed urban, peri-urban, and rural areas, as well as pastoralists, using semistructured topic guides based on the Health Belief Model theory. We conducted a thematic analysis of the discussion using NVivo software. We use Normalization Process Theory to contextualize results as a snapshot of a dynamic process of community adaptation to change to a well-established routine immunization schedule following 2YL introduction.

RESULTS

Routine immunization for infants enjoys resilient demand, grounded in strong community norms despite surprisingly low levels of vaccine literacy. Despite best practices like integration with the established 18-month "weighing visit," demand for 2YL vaccination is still conditional on individual awareness and competition for limited maternal time, household resources, and other health concerns. An embedded norm that children should be fully vaccinated by 12 months originally sustained Expanded Programme for Immunization goals but now discouraged some caregivers from seeking vaccines for children perceived to be "too old" to vaccinate. Caregivers cited greater costs and inconvenience of taking older, heavier children in for vaccination and anticipated criticism from both community members and health care providers for coming "too late."

CONCLUSION

Closing the 2YL vaccination coverage gap will ultimately require modifying embedded norms among caregivers and health care providers alike. Time is necessary but not sufficient to reach this goal. Progress can be accelerated by increasing the level of community and institutional engagement and adapting services where possible to minimize added costs to caregivers of vaccinating older children.

Perennial malaria chemoprevention with and without malaria vaccination to reduce malaria burden in young children: a modelling analysis

BACKGROUND

A recent WHO recommendation for perennial malaria chemoprevention (PMC) encourages countries to adapt dose timing and number to local conditions. However, knowledge gaps on the epidemiological impact of PMC and possible combination with the malaria vaccine RTS,S hinder informed policy decisions in countries where malaria burden in young children remains high.

METHODS

The EMOD malaria model was used to predict the impact of PMC with and without RTS,S on clinical and severe malaria cases in children under the age of two years (U2). PMC and RTS,S effect sizes were fit to trial data. PMC was simulated with three to seven doses (PMC-3-7) before the age of eighteen months and RTS,S with three doses, shown to be effective at nine months. Simulations were run for transmission intensities of one to 128 infectious bites per person per year, corresponding to incidences of < 1 to 5500 cases per 1000 population U2. Intervention coverage was either set to 80% or based on 2018 household survey data for Southern Nigeria as a sample use case. The protective efficacy (PE) for clinical and severe cases in children U2 was calculated in comparison to no PMC and no RTS,S.

RESULTS

The projected impact of PMC or RTS,S was greater at moderate to high transmission than at low or very high transmission. Across the simulated transmission levels, PE estimates of PMC-3 at 80% coverage ranged from 5.7 to 8.8% for clinical, and from 6.1 to 13.6% for severe malaria (PE of RTS,S 10-32% and 24.6-27.5% for clinical and severe malaria, respectively. In children U2, PMC with seven doses nearly averted as many cases as RTS,S, while the combination of both was more impactful than either intervention alone. When operational coverage, as seen in Southern Nigeria, increased to a hypothetical target of 80%, cases were reduced beyond the relative increase in coverage.

CONCLUSIONS

PMC can substantially reduce clinical and severe cases in the first two years of life in areas with high malaria burden and perennial transmission. A better understanding of the malaria risk profile by age in early childhood and on feasible coverage by age, is needed for selecting an appropriate PMC schedule in a given setting.