19 research outputs found

    Geographical and temporal variation in reduction of malaria infection among children under 5 years of age throughout Nigeria.

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    INTRODUCTION: Global progress in reducing malaria has stalled since 2015. Analysis of the situation is particularly needed in Nigeria, the country with by far the largest share of the burden, where approximately a quarter of all cases in the world are estimated to occur. METHODS: We analysed data from three nationwide surveys (Malaria Indicator Surveys in 2010 and 2015 and a National Demographic and Health Survey in 2018), with malaria parasite prevalence in children under 5 years of age determined by sampling from all 36 states of Nigeria, and blood slide microscopy performed in the same accredited laboratory for all samples. Changes over time were evaluated by calculating prevalence ratio (PR) values with 95% CIs for each state, together with Mantel-Haenszel-adjusted PRs (PRadj) for each of the six major geopolitical zones of the country. RESULTS: Between 2010 and 2018, there were significant reductions in parasite prevalence in 25 states, but not in the remaining 11 states. Prevalence decreased most in southern zones of the country (South West PRadj=0.53; South East PRadj=0.59; South South PRadj=0.51) and the North Central zone (PRadj=0.36). Changes in the north were less marked, but were significant and indicated overall reductions by more than 20% (North-West PRadj=0.74; North East PRadj=0.70). Changes in the south occurred mostly between 2010 and 2015, whereas those in the north were more gradual and most continued after 2015. Recent changes were not correlated with survey-reported variation in use of preventive measures. CONCLUSION: Reductions in malaria infection in children under 5 have occurred in most individual states in Nigeria since 2010, but substantial geographical variation in the timing and extent indicate challenges to be overcome to enable global malaria reduction

    Malaria parasite density and detailed qualitative microscopy enhances large-scale profiling of infection endemicity in Nigeria

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    With global progress towards malaria reduction stalling, further analysis of epidemiology is required, particularly in countries with the highest burden. National surveys have mostly analysed infection prevalence, while large-scale data on parasite density and different developmental forms rarely available. In Nigeria, the country with the largest burden globally, blood slide microscopy of children up to 5 years of age was conducted in the 2018 National Demographic and Health Survey, and parasite prevalence previously reported. In the current study, malaria parasite density measurements are reported and analysed for 7783 of the children sampled across the 36 states within the six geopolitical zones of the country. Asexual and sexual stages, and infections with different malaria parasite species are analysed. Across all states of Nigeria, there was a positive correlation between mean asexual parasite density within infected individuals and prevalence of infection in the community (Spearman's rho = 0.39, P = 0.02). Asexual parasite densities were highest in the northern geopolitical zones (geometric means > 2000 μL-1), extending the evidence of exceptionally high infection burden in many areas. Sexual parasite prevalence in each state was highly correlated with asexual parasite prevalence (Spearman's rho = 0.70, P < 0.001), although sexual parasite densities were low (geometric means < 100 μL-1 in all zones). Infants had lower parasite densities than children above 1 year of age, but there were no differences between male and female children. Most infections were of P. falciparum, which had higher asexual densities but lower sexual parasite densities than P. malariae or P. ovale mono-infections. However, mixed species infections had the highest asexual parasite densities. It is recommended that future large surveys in high burden countries measure parasite densities as well as developmental stages and species, to improve the quality of malaria epidemiology and tracking of future changes

    Dynamics of IgG antibody response against Plasmodium antigens among Nigerian infants and young children

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    BackgroundPlasmodium falciparum malaria is a leading cause of child mortality in Nigeria. Neonates are born with maternal antibodies from placental transfer which may protect against malaria infection in the first months of life. The IgG dynamics of the transition from passively transferred antimalarial antibodies to actively acquired IgG from natural exposure have not been well elucidated.MethodsBlood samples collected during a 2018 Nigeria nationwide HIV/AIDS household survey were available for 9,443 children under 5 years of age, with a subset of infants under 2 months of age having maternal samples available (n=41). Samples were assayed for the P. falciparum HRP2 antigen and anti-malarial IgG antibodies. LOESS regression examined the dynamics in IgG response in the first 5 years of life. Correlation with maternal IgG levels was assessed for mother/child pairs.ResultsConsistent decreases were observed in median IgG levels against all Plasmodium spp. antigen targets for the first months of life. At a population level, P. falciparum apical membrane antigen-1 (AMA1) and merozoite surface protein-1 19kD (PfMSP1) IgG decreased during the first 12 months of life before reaching a nadir, whereas IgGs to other targets only declined for the first 4 months of life. Seropositivity showed a similar decline with the lowest seropositivity against AMA1 and PfMSP1 at 10-12 months, though remaining above 50% during the first 2 years of life in higher transmission areas. No protective association was observed between IgG positivity and P. falciparum infection in infants. Maternal antibody levels showed a strong positive correlation with infant antibody levels for all P. falciparum antigens from birth to 2 months of age, but this correlation was lost by 6 months of age.DiscussionMaternally transferred anti-malarial IgG antibodies rapidly decline during the first 6 months of life, with variations among specific antigens and malaria transmission intensity. From 3-23 months of age, there was a wide range in IgG levels for the blood-stage antigens indicating high individual variation in antibody production as children are infected with malaria. Non-falciparum species-specific antigens showed similar patterns in waning immunity and correlation with paired mother’s IgG levels compared to P. falciparum antigens

    Facilitators and barriers to seasonal malaria chemoprevention (SMC) uptake in Nigeria: a qualitative approach

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    BACKGROUND: SMC was adopted in Nigeria in 2014 and by 2021 was being implemented in 18 states, over four months between June and October by 143000 community drug distributors (CDDs) to a target population of 23million children. Further expansion of SMC is planned, extending to 21 states with four or five monthly cycles. In view of this massive scale-up, the National Malaria Elimination Programme undertook qualitative research in five states shortly after the 2021 campaign to understand community attitudes to SMC so that these perspectives inform future planning of SMC delivery in Nigeria. METHODS: In 20 wards representing urban and rural areas with low and high SMC coverage in five states, focus group discussions were held with caregivers, and in-depth interviews conducted with community leaders and community drug distributors. Interviews were also held with local government area and State malaria focal persons and at national level with the NMEP coordinator, and representatives of partners working on SMC in Nigeria. Interviews were recorded and transcribed, those in local languages translated into English, and transcripts analysed using NVivo software. RESULTS: In total, 84 focus groups and 106 interviews were completed. Malaria was seen as a major health concern, SMC was widely accepted as a key preventive measure, and community drug distributors (CDDs) were generally trusted. Caregivers preferred SMC delivered door-to-door to the fixed-point approach, because it allowed them to continue daily tasks, and allowed time for the CDD to answer questions. Barriers to SMC uptake included perceived side-effects of SMC drugs, a lack of understanding of the purpose of SMC, mistrust and suspicions that medicines provided free may be unsafe or ineffective, and local shortages of drugs. CONCLUSIONS: Recommendations from this study were shared with all community drug distributors and others involved in SMC campaigns during cascade training in 2022, including the need to strengthen communication about the safety and effectiveness of SMC, recruiting distributors from the local community, greater involvement of state and national level pharmacovigilance coordinators, and stricter adherence to the planned medicine allocations to avoid local shortages. The findings reinforce the importance of retaining door-to-door delivery of SMC

    A qualitative look at bed net access and use in Burkina Faso, Mozambique, Nigeria, and Rwanda following piloted distributions of dual-active ingredient insecticide-treated nets

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    Background: Universal coverage with insecticide-treated nets (ITNs) is important for malaria control and elimination. The emergence and intensification of insecticide resistance threatens progress made through the deployment of these interventions and has required the development of newer, more expensive ITN types. Understanding malaria prevention behaviour, including barriers and facilitators to net access and use, can support effective decision-making for the promotion and distribution of ITNs. Methods: In-depth interviews and focus group discussions were conducted in 3 to 4 villages per district, in 13 districts across Burkina Faso, Mozambique, Nigeria and Rwanda from 2019 to 2022. Interviews were conducted in the local language, translated and transcribed in English, French or Portuguese. Transcripts were coded and analysed using Nvivo and ATLAS.ti. Results: ITNs were obtained from mass distribution campaigns, antenatal care and immunization visits, and purchased on the private market in some locations. While there were divergent perspectives in whether the number of distributed nets were adequate, participants consistently expressed concerns of bias, discrimination, and a lack of transparency with the distribution process. ITNs were frequently used alongside other malaria prevention methods. The primary motivation for use was malaria prevention. While some participants reported using nets nightly throughout the year, other participants reported seasonal use, both due to the perceived higher density of mosquitoes and discomfort of sleeping under a net in the increased heat. Other barriers to consistent net use included activities that take place away from the home, sleeping patterns and arrangements, and sensitivity to the insecticides on the nets. Conclusions: ITNs remain an important malaria control intervention. To ensure adequate and increased net access, distribution campaigns should consider family structures, available sleeping spaces, and other bed sharing preferences when identifying the number of nets needed for distribution. In addition, campaigns should allow for multiple options for net distribution points and timing to accommodate households remote to health services. Continuous distribution channels and complimentary distribution through the private sector could help fill gaps in coverage. Solutions are needed for outdoor malaria transmission, including alternative designs for ITNs, and improving access to complementary personal protective measures

    Design and methods for a quasi-experimental pilot study to evaluate the impact of dual active ingredient insecticide-treated nets on malaria burden in five regions in sub-Saharan Africa

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    Background:Vector control tools have contributed significantly to a reduction in malaria burden since 2000, primar‑ily through insecticidal‑treated bed nets (ITNs) and indoor residual spraying. In the face of increasing insecticide resist‑ance in key malaria vector species, global progress in malaria control has stalled. Innovative tools, such as dual active ingredient (dual‑AI) ITNs that are effective at killing insecticide‑resistant mosquitoes have recently been introduced. However, large‑scale uptake has been slow for several reasons, including higher costs and limited evidence on their incremental effectiveness and cost‑effectiveness. The present report describes the design of several observational studies aimed to determine the effectiveness and cost‑effectiveness of dual‑AI ITNs, compared to standard pyre‑throid‑only ITNs, at reducing malaria transmission across a variety of transmission settings.Methods:Observational pilot studies are ongoing in Burkina Faso, Mozambique, Nigeria, and Rwanda, leveraging dual‑AI ITN rollouts nested within the 2019 and 2020 mass distribution campaigns in each country. Enhanced surveil‑lance occurring in select study districts include annual cross‑sectional surveys during peak transmission seasons, monthly entomological surveillance, passive case detection using routine health facility surveillance systems, and studies on human behaviour and ITN use patterns. Data will compare changes in malaria transmission and disease burden in districts receiving dual‑AI ITNs to similar districts receiving standard pyrethroid‑only ITNs over three years. The costs of net distribution will be calculated using the provider perspective including financial and economic costs, and a cost‑effectiveness analysis will assess incremental cost‑effectiveness ratios for Interceptor® G2, Royal Guard®, and piperonyl butoxide ITNs in comparison to standard pyrethroid‑only ITNs, based on incidence rate ratios calcu‑lated from routine data.Conclusions:Evidence of the effectiveness and cost‑effectiveness of the dual‑AI ITNs from these pilot studies will complement evidence from two contemporary cluster randomized control trials, one in Benin and one in Tanzania, to provide key information to malaria control programmes, policymakers, and donors to help guide decision‑making and planning for local malaria control and elimination strategies. Understanding the breadth of contexts where these dual‑AI ITNs are most effective and collecting robust information on factors influencing comparative effectiveness could improve uptake and availability and help maximize their impact

    The role of the Deki Reader™ in malaria diagnosis, treatment and reporting: findings from an Africare pilot project in Nigeria

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    Abstract Background The Deki Reader is a diagnostic device used with rapid diagnostic tests (RDTs) and linked to an online database for real-time uploads of patient information and results. This is in contrast to visual interpretation of malaria RDTs recorded on the District Health Information System (DHIS). This paper compares records for use of the Deki Reader with DHIS records of visual interpretation of RDTs. Results A total of 4063 patient encounters/tests were recorded on the Deki Reader database between June 1st and December 31st, 2016. These tests were for 2629 persons who presented with fever and had RDT done. In comparison, data from DHIS 2.0 for same period recorded 7201 persons presenting with fever. 2421 out of the 2629 persons (92.1%), received RDT using Deki Reader compared to 6535 out of 7201 persons (90.4%) recorded on DHIS (p = 0.04). From DHIS records, malaria positivity rate was 51.6% (3375 out of 6535 persons) compared to Deki Reader records of 23.6% (572 out of 2421 persons). The difference between these two rates was significant (p < 0.001). The odds ratio (95% CI) for the association between use of Deki Reader and having a positive malaria result was 0.29 (0.26–0.32). DHIS showed that 4008 persons received Artemisinin-based combination therapy (ACT) while 3989 persons tested positive with RDT or microscopy, compared to 691 out of 705 persons (98.0%) using Deki Reader. Finally, Deki Reader identified 618 processing and manufacturers errors with an error rate of 15.3%. Conclusion The Deki Reader is likely a useful tool for malaria diagnosis, treatment, and real-time data management. It potentially improves diagnostic quality, reduces wastage in ACT administration and improves data quality

    Assessing availability, prices, and market share of quality-assured malaria ACT and RDT in the private retail sector in Nigeria and Uganda

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    Abstract Background An estimated 50% of suspected malaria cases in sub-Saharan Africa first seek care in the private sector, especially in private medicine retail outlets. Quality of care in these outlets is generally unknown but considered poor with many patients not receiving a confirmatory diagnosis or the recommended first-line artemisinin-based combination therapy (ACT). In 2010, a subsidy pilot scheme, the Affordable Medicines Facility malaria, was introduced to crowd out the use of monotherapies in favour of WHO-pre-qualified artemisinin-based combinations (WHO-PQ-ACTs) in the private health sector. The scheme improved the availability, market share, and cost of WHO-PQ-ACTs in countries like Nigeria and Uganda, but in 2018, the subsidies were halted in Nigeria and significantly reduced in Uganda. This paper presents findings from six retail audit surveys conducted from 2014 to 2021 in Nigeria and Uganda to assess whether the impact of subsidies on the price, availability, and market share of artemisinin-based combinations has been sustained after the subsidies were reduced or discontinued. Methods Six independent retail audits were conducted in private medicine retail outlets, including pharmacies, drug shops, and clinics in Nigeria (2016, 2018, 2021), and Uganda (2014, 2019, 2020) to assess the availability, price, and market share of anti-malarials, including WHO-PQ-ACTs and non-WHO-PQ-ACTs, and malaria rapid diagnostic tests (RDTs). Results Between 2016 and 2021, there was a 57% decrease in WHO-PQ-ACT availability in Nigeria and a 9% decrease in Uganda. During the same period, non-WHO-PQ-ACT availability increased in Nigeria by 41% and by 34% in Uganda. The price of WHO-PQ-ACTs increased by 42% in Nigeria to 0.68andincreasedinUgandaby240.68 and increased in Uganda by 24% to 0.95. The price of non-WHO-PQ-ACTs decreased in Nigeria by 26% to 1.08anddecreasedinUgandaby641.08 and decreased in Uganda by 64% to 1.23. There was a 76% decrease in the market share of WHO-PQ-ACTs in Nigeria and a 17% decrease in Uganda. Malaria RDT availability remained low throughout. Conclusion With the reduction or termination of subsidies for WHO-PQ-ACTs in Uganda and Nigeria, retail prices have increased, and retail prices of non-WHO-PQ-ACTs decreased, likely contributing to a shift of higher availability and increased use of non-WHO-PQ-ACTs

    Setting a Nigeria national malaria operational research agenda: the process

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    Abstract Background Employing malaria operational research (MOR) findings in planning national malaria control programmes is gaining increased attention. The malaria control foci are diverse, resources are limited; therefore, agreeing on priority areas is critical. Hitherto, the process of prioritising MOR questions in Nigeria has been limited to few stakeholders. In support of the National Malaria Elimination Programme’s (NMEP) effort at setting a MOR agenda, the Nigeria Field Epidemiology and Laboratory Training Programme (NFELTP) in collaboration with NMEP conducted preliminary exploratory study to identify key malaria research gaps and needs, and provide data to inform setting a robust national MOR agenda. The process of generating data is presented in this paper. Methods A twelve-member task-team comprising NFELTP, university researchers and NMEP officers was commissioned. Following an inaugural meeting the task-team developed a framework of activities and held five planning meetings, conducted five-week online and self-administered paper-based surveys, key informant interview (KII), two-day desk review workshop, seven-day qualitative data analysis, ten-day result and five-day report writing workshops. Paired group members conducted the interviews across six geopolitical zones of Nigeria. Abridged study report was used for a two-day MOR setting agenda stakeholders’ workshop. Results A structured framework, study protocol and data collection instruments were developed and submitted for ethical approval. The instruments included survey questionnaire for detailed information on researchers and other stakeholders’ experience with MOR, the gaps and needs in thematic MOR areas; KII and Delphi guides. After an initial scoping review, primary data were collected from purposively selected survey participants using mixed methods: - online survey (n = 100), self-administered paper-based survey (n = 85), KII (n = 40), desk review workshop (n = 22) and Delphi interviews (n = 8). Comprehensive lists of research gaps/bottlenecks and needs were generated for each thematic area in malaria control. These were used at a two-day national MOR setting stakeholder workshop (n = 54) to guide the development of national MOR agenda document. Conclusions A systematic approach involving broad stakeholder engagement provided data and evidence-based information for development of a robust national MOR agenda. The processes involved are recommended for use in malaria endemic settings
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