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Abstract The need for evidence-based data, to inform policy decisions on malaria vector control interventions in Nigeria, necessitated the establishment of mosquito surveillance sites in a few States in Nigeria. In order to make evidence-based-decisions, predictive studies using available data becomes imperative. We therefore predict the distribution of the major members of the Anopheles gambiae s.l. in Nigeria. Immature stages of Anopheles were collected from 72 study locations which span throughout the year 2020 resulted in the identification of over 60,000 Anopheline mosquitoes. Of these, 716 breeding sites were identified with the presence of one or more vector species from the An. gambiae complex and were subsequently used for modelling the potential geographical distribution of these important malaria vectors. Maximum Entropy (MaxEnt) distribution modeling was used to predict their potentially suitable vector habitats across Nigeria. A total of 23 environmental variables (19 bioclimatic and four topographic) were used in the model resulting in maps of the potential geographical distribution of three dominant vector species under current climatic conditions. Members of the An. gambiae complex dominated the collections (98%) with Anopheles stephensi, Anopheles coustani, Anopheles funestus, Anopheles moucheti, Anopheles nilli also present. An almost equal distribution of the two efficient vectors of malaria, An. gambiae and Anopheles coluzzii, were observed across the 12 states included in the survey. Anopheles gambiae and Anopheles coluzzii had almost equal, well distributed habitat suitability patterns with the latter having a slight range expansion. However, the central part of Nigeria (Abuja) and some highly elevated areas (Jos) in the savannah appear not suitable for the proliferation of these species. The most suitable habitat for Anopheles arabiensis was mainly in the South-west and North-east. The results of this study provide a baseline allowing decision makers to monitor the distribution of these species and establish a management plan for future national mosquito surveillance and control programs in Nigeria.

Abstract Background Resistance monitoring is essential in ensuring the success of insecticide based vector control programmes. This study was carried out to assess the susceptibility status of urban populations of Anopheles gambiae to carbamate insecticide being considered for vector control in mosquito populations previously reported to be resistant to DDT and permethrin. Methods Two – three day old adult female Anopheles mosquitoes reared from larval collections in 11 study sites from Local Government Areas of Lagos were exposed to test papers impregnated with DDT 4%, deltamethrin 0.05% and propoxur 0.1% insecticides. Additional tests were carried out to determine the susceptibility status of the Anopheles gambiae population to bendiocarb insecticide. Members of the A. gambiae complex, the molecular forms, were identified by PCR assays. The involvement of metabolic enzymes in carbamate resistance was assessed using Piperonyl butoxide (PBO) synergist assays. The presence of kdr-w/e and ace-1R point mutations responsible for DDT-pyrethroid and carbamate resistance mechanisms was also investigated by PCR. Results Propoxur resistance was found in 10 out of the 11 study sites. Resistance to three classes of insecticides was observed in five urban localities. Mortality rates in mosquitoes exposed to deltamethrin and propoxur did not show any significant difference (P > 0.05) but was significantly higher (P A. gambiae s.s (M form). The kdr -w point mutation at allelic frequencies between 45%-77% was identified as one of the resistant mechanisms responsible for DDT and pyrethroid resistance. Ace-1R point mutation was absent in the carbamate resistant population. However, the possible involvement of metabolic resistance was confirmed by synergistic assays conducted. Conclusion Evidence of carbamate resistance in A. gambiae populations already harbouring resistance to DDT and permethrin is a clear indication that calls for the implementation of insecticide resistance management strategies to combat the multiple resistance identified.

Abstract Background Mefloquine-artesunate is a formulation of artemisinin based combination therapy (ACT) recommended by the World Health Organization and historically the first ACT used clinically. The use of ACT demands constant monitoring of therapeutic efficacies and drug levels, in order to ensure that optimum drug exposure is achieved and detect reduced susceptibility to these drugs. Quantification of anti-malarial drugs in biological fluids other than blood would provide a more readily applicable method of therapeutic drug monitoring in developing endemic countries. Efforts in this study were devoted to the development of a simple, field applicable, non-invasive method for assay of mefloquine in saliva. Methods A high performance liquid chromatographic method with UV detection at 220 nm for assaying mefloquine in saliva was developed and validated by comparing mefloquine concentrations in saliva and plasma samples from four healthy volunteers who received single oral dose of mefloquine. Verapamil was used as internal standard. Chromatographic separation was achieved using a Hypersil ODS column. Results Extraction recoveries of mefloquine in plasma or saliva were 76-86% or 83-93% respectively. Limit of quantification of mefloquine was 20 ng/ml. Agreement between salivary and plasma mefloquine concentrations was satisfactory (r = 0.88, p < 0.001). Saliva:plasma concentrations ratio was 0.42. Conclusion Disposition of mefloquine in saliva paralleled that in plasma, making salivary quantification of mefloquine potentially useful in therapeutic drug monitoring.

Abstract Background Combination treatments, preferably containing an artemisinin derivative, are recommended to improve efficacy and prevent Plasmodium falciparum drug resistance. Artemether-lumefantrine (AL) and artesunate-amodiaquine (AA) are efficacious regimens that have been widely adopted in sub-Saharan Africa. However, most study designs ignore the effects of these regimens on peripheral parasitaemia in the first 24 hours of therapy. The study protocol was designed to evaluate more closely the early effects and the standard measures of efficacies of these two regimens. Methods In an open label, randomized controlled clinical trial, children aged 12 months to 132 months were randomized to receive AL (5-14 kg, one tablet; 15-24 kg, two tablets and 25-34 kg, three tablets twice daily) or artesunate (4 mg/kg daily) plus amodiaquine (10 mg/kg daily) for three days. Peripheral blood smears were made hourly in the first 4 hours, 8 h, 16 h, 24 h, and daily on days 2-7, and on days 7, 14, 21, 28, 35, and 42 for microscopic identification and quantification of Plasmodium falciparum. Results A total of 193 children were randomized to receive either AL (97) or AA (96). In children that received both medications, early response of peripheral parasitaemia showed that 42% of children who received AL and 36.7% of those who received AA had an immediate rise in peripheral parasitaemia (0-4 h after treatment) followed by a rapid fall. The rise in parasitaemia was significant and seems to suggest a mobilization of asexual parasites from the deep tissues to the periphery. Days 3, 7, 14, 28, and 42 cure rates in the per protocol (PP) population were > 90% in both groups of children. Both drug combinations were well tolerated with minimal side effects. Conclusion The study showed the high efficacy of AL and AA in Nigerian children. In addition the study demonstrated the mobilisation of asexual parasites from the deep to the periphery in the early hours of commencing ACT treatment in a subset of patients in both study groups. It is unclear whether the early parasite dynamics discovered in this study play any role in the development of drug resistance and thus it is important to further evaluate this discovery. It may be useful for studies investigating delay in parasite clearance of artemisinin derivatives as a way of monitoring the development of resistance to artemisinin to assess the early effects of the drugs on the parasites.

Abstract Background Prescription practices have been shown to influence the emergence of anti-malarial drug resistance. Thus efforts in this study were devoted to evaluating the prescribing practices prior to introduction of the artemisinin based combination therapy (ACT) in Nigeria and its potential contribution to emergence of chloroquine resistant malaria in south-west Nigeria, in order to forestall a similar situation with the ACT. Methods A retrospective quantitative study was designed to examine case records of patients treated for malaria in either a government or a private hospital in Ibadan, south-west Nigeria, over a 20-year period, cutting across three phases of resistance to chloroquine in Nigeria: pre-resistance, emerging resistance and dissemination of resistance. Patient prescriptions were examined for use of anti-malarial drugs, sub-therapeutic doses of chloroquine, co-administration of anti-histamines with chloroquine. Descriptive statistics of frequency and percentage were used to describe trends in the parameters assessed using EPI-info. Results Case record files of 2,529 patients were examined. Chloroquine was the main drug used in treatment of malaria throughout the periods studied, with frequency of prescription at both sites ranging from 91.4% to 98.3% during the pre-resistance years. It was administered as standard doses during the pre resistance years. Anti-histamines, especially promethazine, were routinely co-administered with chloroquine at this period too. However, the practice of prescribing sub-therapeutic doses of chloroquine at the private health care facility coincided with the latter phase of emerging resistance and phase of dissemination of resistance. Frequency of prescription of sub-therapeutic doses increased from 6.7% in 1983 (pre-resistance years) to 43.6% in 1997 (dissemination of resistance phase) at the private health care facility. Frequency of co-administration of anti-histamines with chloroquine also reduced during the period of dissemination of resistance. Conclusion The results from this study describe a lack of adherence to national treatment guidelines, especially in the private sector, and a relationship between prescription practices and dissemination of drug resistant falciparum malaria. As Nigeria adopts the use of ACT, there is an urgent need to improve malaria treatment practices in Nigeria in order to prolong the clinical shelf-life of the combination.

Abstract Background Artesunate plus sulphadoxine-pyrimethamine is one of the four artemisinin-based combination therapies currently recommended by WHO as first-line treatment for falciparum malaria. Sulphadoxine-pyrimethamine is also used for intermittent preventive treatment for malaria in pregnancy. Drug use patterns and drug pharmacokinetics are important factors impacting the spread of drug resistant parasites hence it is imperative to monitor the effect of pharmacokinetic variability on therapeutic efficacy. Unfortunately, information on the pharmacokinetics of sulphadoxine in children and pregnant women with malaria is very limited. Methods for the assay of sulphadoxine-pyrimethamine have been previously reported, but they are not cost-effective and practicable in analytical laboratories in low resource areas where malaria is endemic. Efforts in this study were thus devoted to development and evaluation of a simple, cost-effective and sensitive method for quantification of sulphadoxine in small capillary samples of whole blood dried on filter paper. Methods Sulphadoxine was determined in whole blood by reversed-phase high performance liquid chromatography with UV detection at 340 nm. Sulisoxazole (SLX) was used as internal standard. Chromatographic separation was achieved using a Beckman Coulter ODS C18 and a mobile phase consisting of 0.05 M phosphate buffer-methanol-acetonitrile (70:17:13 V/V/V) containing 1% triethylamine solution. Results Standard curves from sulphadoxine-spiked blood added to filter paper were linear over the concentration range studied. Linear regression analysis yielded correlation coefficient r2 > 0.99 (n = 6). Extraction recoveries were about 82-85%. The limit of quantification was 120 ng/ml while the within and between assay coefficient of variations were < 10%. The inter-day precision was < 5.8% and inter-day accuracy ranged from 4.1 to 5.3%. There was no interference from endogenous compounds or any of the commonly used anti-malarial, analgesic and anti-infective drugs with the peaks of SDX or the internal standard. Conclusion The recovery and accuracy of determination of SDX from whole blood filter paper samples using the method described in this study is satisfactory, thus making the method a valuable tool in epidemiological studies and therapeutic drug monitoring in developing endemic countries. Furthermore, the applicability of the method in studying the pharmacokinetic disposition of SDX in a patient suggests that the method is suitable in malaria endemic areas.

Abstract Background The six-dose regimen of artemether-lumefantrine (AL) is now considered the gold standard for the treatment of uncomplicated Plasmodium falciparum malaria. There are few reports evaluating co-artemether in very young Nigerian infants and children. Results of the evaluation of the six-dose regimen in very young infants and children in Nigeria are presented in this report. Methods As part of a larger African study, this open label, non-comparative trial, assessed the efficacy and safety of six-dose regimen of AL tablets in 103 Nigerian infants and children weighing between five and 25 kg suffering from acute uncomplicated malaria. Treatment was administered under supervision over three days with children as in-patients. 12-lead ECG tracings were taken pre-treatment and at day 3. Results Ninety-three infants and children completed the study as stipulated by the protocol. Mean fever and parasite clearance times for the intent to treat population (ITT) were 24.9 h ± (1.28) and 26 h ± (4.14) and the corresponding figures for the per-protocol population (PP) were 19.24 h ± 13.9 and 25.62 h ± 11.25 respectively. Day 14 cure rates for the ITT and PP were 95.1% and 100% respectively while day 28 cure rates were 91.3% and 95.7% respectively. The overall PCR corrected day 28 cure rate was 95.1% for the ITT. The six-dose regimen of AL was well tolerated with no drug-related serious adverse events. Although six patients recorded a QTc prolongation of > 60 ms on D3 over D0 recording, no patient recorded a QTc interval > 500 ms. Conclusion The six-dose regimen of AL tablets is safe and effective for the treatment of acute uncomplicated malaria in Nigerian infants and children weighing between five and 25 kg. Trial registration NCT00709969

Abstract Background Many Nigerian children with malaria are treated at home. Treatments are mostly incorrect, due to caregivers' poor knowledge of appropriate and correct dose of drugs. A comparative study was carried out in two rural health districts in southwest Nigeria to determine the effectiveness of a guideline targeted at caregivers, in the treatment of febrile children using chloroquine. Methods Baseline and post intervention knowledge, attitude and practice household surveys were conducted. The intervention strategy consisted of training a core group of mothers ("mother trainers") in selected communities on the correct treatment of malaria and distributing a newly developed treatment guideline to each household. "Mother trainers" disseminated the educational messages about malaria and the use of the guideline to their communities. Results Knowledge of cause, prevention and treatment of malaria increased with the one-year intervention. Many, (70.4%) of the respondents stated that they used the guideline each time a child was treated for malaria. There was a significant increase in the correct use of chloroquine from 2.6% at baseline to 52.3% after intervention among those who treated children at home in the intervention arm compared with 4.2% to 12.7% in the control arm. The correctness of use was significantly associated with use of the guideline. The timeliness of commencing treatment was significantly earlier in those who treated febrile children at home using chloroquine than those who took their children to the chemist or health facility (p < 0.005). Mothers considered the guideline to be explicit and useful. Mother trainers were also considered to be effective and acceptable. Conclusion The use of the guideline with adequate training significantly improved correctness of malaria treatment with chloroquine at home. Adoption of this mode of intervention is recommended to improve compliance with drug use at home. The applicability for deploying artemisinin-based combination therapy at the community level needs to be investigated.

Abstract Background In vitro and in vivo resistance of Plasmodium falciparum to atovaquone or atovaquone-proguanil hydrochloride combination has been associated to two point mutations in the parasite cytochrome b (cytb) gene (Tyr268Ser and Tyr268Asn). However, little is known about the prevalence of codon-268 mutations in natural populations of P. falciparum without previous exposure to the drug in Africa. Methods The prevalence of codon-268 mutations in the cytb gene of African P. falciparum isolates from Nigeria, Malawi and Senegal, where atovaquone-proguanil has not been introduced for treatment of malaria was assessed. Genotyping of the cytb gene in isolates of P. falciparum was performed by PCR-restriction fragment length polymorphism and confirmed by sequencing. Results 295 samples from Nigeria (111), Malawi (91) and Senegal (93) were successfully analyzed for detection of either mutant Tyr268Ser or Tyr268Asn. No case of Ser268 or Asn268 was detected in cytb gene of parasites from Malawi or Senegal. However, Asn268 was detected in five out of 111 (4.5%) unexposed P. falciparum isolates from Nigeria. In addition, one out of these five mutant Asn268 isolates showed an additional cytb mutation leading to a Pro266Thr substitution inside the ubiquinone reduction site. Conclusion No Tyr268Ser mutation is found in cytb of P. falciparum isolates from Nigeria, Malawi or Senegal. This study reports for the first time cytb Tyr268Asn mutation in unexposed P. falciparum isolates from Nigeria. The emergence in Africa of P. falciparum isolates with cytb Tyr268Asn mutation is a matter of serious concern. Continuous monitoring of atovaquone-proguanil resistant P. falciparum in Africa is warranted for the rational use of this new antimalarial drug, especially in non-immune travelers.

Abstract Background People with severe mental illnesses (SMI) such as schizophrenia die on average 15 to 20 years earlier than everyone else. Two thirds of these deaths are from preventable physical illnesses such as hypertension, cardiovascular disease, and diabetes, which are worsened by weight gain. Antipsychotics are associated with significant weight gain. In REalist Synthesis Of non-pharmacologicaL interVEntions (RESOLVE), a realist synthesis, combining primary and secondary data, will be used to understand and explain how, why, for whom, and in what contexts non-pharmacological interventions can help service users to manage antipsychotic-induced weight gain. Methods A five-step approach will be used to develop guidance: 1. Developing the initial programme theory An initial (candidate) programme theory, which sets out how and why outcomes occur within an intervention, will be developed. 2. Developing the search The initial programme theory will be refined using academic and grey literature. The proposed initial sampling frame are as follows: Context: people living with SMI, taking antipsychotics, different types of SMI. Intervention: non-pharmacological interventions. Mechanisms: triggered by the intervention. Outcomes e.g. weight, metabolic adverse events, quality of life, adherence, burden, economic. Searching for relevant documents will continue until sufficient data is found to conclude that the refined programme theory is coherent and plausible. Lived experience (service users) and stakeholder (practitioners) groups will provide feedback. 3. Selection, appraisal and data extraction Documents will be screened against inclusion and exclusion criteria. The text extracted from these documents will be coded as contexts, mechanisms and their relationships to outcomes. 4. Primary data collection Realist interviews with up to 30 service users and informal carers, and 20 practitioners will gather data to support, refute or refine the programme theory. 5. Data analysis A realist logic of analysis will be used to develop and refine the programme theory from secondary and primary data. The analysis will aim to identify practical intervention strategies to change contexts so that key mechanisms are triggered to produce desired outcomes. Guidance will be produced based on these strategies. Discussion This realist synthesis aims to develop guidance for service users and practitioners on the most appropriate interventional strategies to manage and limit antipsychotic weight gain. Systematic review registration PROSPERO: CRD42021268697

Sickle cell anaemia (SCA) is a form of haemolytic anaemia caused by an abnormal composition of the globin chains of haemoglobin. When the mutated haemoglobin is exposed to low-oxygen concentration, it polymerizes into long crystals of red blood cells giving the cell an abnormal sickled shape with extreme fragility, and less flexible erythrocytes with a reduced lifespan and various complications including inflammation and oxidative stress which has been implicated in SCD patients. This study investigated the relationship between markers of inflammatory and oxidative stress in alloimmunized sickle cell patients. Hundred participants were involved in the study; fifty SCD aged 18 to 48 from Obafemi Awolowo University Health Centre, and a control group of fifty individuals without the disease. This is a cross-sectional study undertaken at the Department of Haematology and Immunology, Obafemi Awolowo University Teaching Hospital, Ile-Ife Osun State, Nigeria. The samples were analysed for inflammatory and oxidative biomarkers as well as liver and kidney function tests following the manufacturer's instructions. Biochemical parameters and inflammatory markers show a statistically significant increase (p=0.003) in the means of test groups compared to the means of the control groups for the following: SOD (pg/mL)=284.2, AST (µ/L)=46.94, ALT (µ/L)=37.0, CREAT (µmoI/L)=56.71, and Urea (µmoI/L)=3.4. A significant difference (p=0.003) between the means of CRP (ng/mL)=3.9 and TNF (pg/mL)=8.1 in the test groups compared to the control groups. Frequent transfusions in SCD serve to prevent and alleviate microcirculatory complications and the breakdown of red cells that incite inflammation and oxidative stress, potentially mimicking alloimmunization, and reducing the risk of organ damage. Oxidative and Inflammatory markers should be included in the proper monitoring of SCD patients. [ABSTRACT FROM AUTHOR]

Abstract Background Decision making process for Official Development Assistance (ODA) for healthcare sector in low-income and middle-income countries involves multiple agencies, each with their unique power, priorities and funding mechanisms. This process at country level has not been well studied. Methods This paper developed and applied a new framework to analyze decision-making process for priority setting in Ethiopia, Nigeria, and Tanzania, and collected primary data to validate and refine the model. The framework was developed following a scoping review of published literature. Interviews were then conducted using a pre-determined interview guide developed by the research team. Transcripts were reviewed and coded based on the framework to identify what principles, players, processes, and products were considered during priority setting. Those elements were further used to identify where the potential capacity of local decision-makers could be harnessed. Results A framework was developed based on 40 articles selected from 6860 distinct search records. Twenty-one interviews were conducted in three case countries from 12 institutions. Transcripts or meeting notes were analyzed to identify common practices and specific challenges faced by each country. We found that multiple stakeholders working around one national plan was the preferred approach used for priority setting in the countries studied. Conclusions Priority setting process can be further strengthened through better use of analytical tools, such as the one described in our study, to enhance local ownership of priority setting for ODA and improve aid effectiveness.

Background: Current research has identified how ethnic minority women experience poorer health outcomes during the perinatal period. In the United Kingdom, specialist perinatal mental health services provide mental health treatment for women throughout the perinatal period. Service users have previously highlighted that perinatal services are hard to access and lack cultural sensitivity, whereas healthcare professionals have described limited opportunities and resources for developing cultural competency. Objectives: We explored the experiences of ethnic minority women with National Health Service (NHS) specialist perinatal teams and identified what culturally sensitive perinatal mental health care means to this group. Design: Individual semi‐structured interviews were conducted, and an interpretative phenomenological analysis framework was used to analyse the interview transcripts. Setting and Participants: Participants were recruited from NHS specialist perinatal teams and online via social media. Results: Six women were interviewed. Four group experiential themes central to the experiences of participants emerged: (1) strengthening community networks and peer support; (2) valuing cultural curiosity; (3) making sense of how culture, ethnicity, race and racism impact mental health; and (4) tailoring interventions to ethnic minority women and their families. Discussion and Conclusions: The findings capture how ethnic minority women experience specialist perinatal teams and offer insights into practising culturally sensitive care. Perinatal mental health professionals can support ethnic minority women by strengthening their access to community resources and peer support; being curious about their culture; helping them to make sense of how culture, ethnicity, race and mental health interact; and applying cultural and practical adaptations to interventions. Patient or Public Contribution: A Lived Experience Advisory Group (LEAG) of women from ethnic minority groups contributed to the design and conduct of this study. The LEAG had lived experience of perinatal mental health conditions and accessing specialist perinatal teams. The LEAG chose to co‐produce specific aspects of the research they felt fit with their skills and available time throughout five group sessions. These aspects included developing the interview topic guide, a structure for debriefing participants and advising on the social media recruitment strategy. [ABSTRACT FROM AUTHOR]

The study was motivated by increased carbon emissions and high inequality in many of the countries in sub-Saharan Africa (SSA). In this study, we examine whether income inequality in SSA countries increases CO2 emissions, and also investigate empirically whether financial inclusion and institutional quality moderate this connection from the period 2000–2018. For the purpose of examining these links, two proxies for financial inclusion (FI) and an index of institutional quality (IQX) are used. Advanced econometric techniques such as cross-sectional augmented autoregressive distributed lags (CS-ARDL) and augmented mean group (AMG) techniques were used to account for robust, cross-sectional dependence and heterogeneity. The CD-ARDL results demonstrate that the inequalities in the short and long runs are essentially positive, indicating that environmental pollution would rise progressively as the wealth difference widened in the 32 selected SSA nations. The square of income disparity has a negative impact on CO2 emissions, albeit the magnitude varies in the short and long run. Income disparity continues to have a positive impact on CO2 emissions after interacting with financial inclusion in both the short and long run. The results of the interaction term (INEQ*IQX) show that institutional quality has a considerable negative effect on CO2, implying that institutional quality has a major impact on the inequality-CO2 nexus. The robustness of the models is tested using AMG, and the results are congruent with the CS-ARDL estimated results. Hence, based on our findings, we recommend several measures to reduce CO2 emissions in SSA countries. [ABSTRACT FROM AUTHOR]