Malaria Endemic Countries In Africa Research Articles

Understanding the China-Tanzania Malaria Control Project: lessons learned from a multi-stakeholder qualitative study.

Tanzania is among the countries with the highest malaria cases and deaths worldwide, where vulnerable populations have been severely affected due to poverty and weakness in health system and infrastructure. The China-Tanzania Malaria Control Project (the Project) was a two-phase global health intervention project implemented between 2015 and 2021 that aimed to transfer project-designated intervention experience in malaria elimination to the Tanzanian health system. This study aims to identify the barriers and facilitators encountered during the Project and to improve our understanding of the emerging phenomenon of South-South global health collaboration. We conducted thematic analysis of qualitative data collected from a purposive sample of 14 participants from multiple stakeholders including project management office, project implementation agency, funding partners and external evaluators of the Project. A conceptual framework was developed to construct the interviews guides. The interviews were transcribed verbatim, crossover checked, translated into English, and analyzed with NVivo 12.0. We conducted the open coding followed by the axial coding based on the Grounded Theory to generate themes and subthemes, and identified key influencing factors that aided or hindered the malaria control in Tanzania. The findings suggested that malaria control strategies should largely be tailored due to varied socioeconomic contexts. The perceived enablers in practice include project-designated intervention experiences and technologies, professional and self-learning capabilities of the implementation team, sustainable financial assistance, and support from the international partners. The barriers include the shortage of global health talents, existing gaps to meet international standards, defects in internal communication mechanisms, inadequacy of intergovernmental dialogue, and limitations in logistical arrangements. A checklist and policy implications for China's future engagement in malaria control in resource-limited settings have been proposed. The initiative of Health Silk Road has generated strong global interest in promoting development assistance in health. In the hope of generalizing the evidence-based interventions to high malaria-endemic countries in Africa, the need for China to carefully face the challenges of funding gaps and the lack of support from recipient governments remains ongoing. It is recommended that China should form an institutionalized scheme and sustainable funding pool to ensure the steady progress of development assistance in health.

Changes in the associations between malaria incidence and climatic factors across malaria endemic countries in Africa and Asia-Pacific region

Empirical evidence supporting the associations between malaria incidence and climatic factors has remained controversial, buffering the progress in the Global Malaria Program that aims to eliminate 90% of the world malaria burden by 2030. This study has aimed to evaluate the nature and extent at which these relations are maintained across all the malaria endemic countries of Africa and Asia-Pacific region. We have utilized the last two decades of malaria incidence, annual minimum temperature, and annual precipitation time series data (2000–2020) for the two most malaria-impacted regions. These data were fitted in the generalized linear model and the mixed effects model. The results showed that there exists a large heterogeneity in malaria incidence across the countries, and between the regions. Last two decadal tendencies showed significant reductions in the disease burden in almost all the countries in the Asia Pacific, with several exceptions or relatively slowed reductions in the Africa. We found significant changes in the positive linear associations between malaria incidence, annual minimum temperature, and annual precipitation across African countries. Many Asia-Pacific countries namely Bangladesh, Bhutan, Indonesia, South Korea, Nepal, Thailand, Vietnam showed negative effects in the associations with the annual precipitation. This study indicates that increasing temperature within the range of 12–30 °C can generate positive effects on malaria incidence, but the nature and extent of precipitation effects vary across countries and at a large regional scale.

Multilevel logistic regression modelling to quantify variation in malaria prevalence in Ethiopia.

Ethiopia has low malaria prevalence compared to most other malaria-endemic countries in Africa. However, malaria is still a major public health problem in the country. The binary logistic regression model has been widely used to analyse malaria indicator survey (MIS) data. However, most MIS have a hierarchical structure which may result in dependent data. Since this model assumes that conditional on the covariates the malaria statuses of individuals are independent, it ignores potential intra-cluster correlation among observations within a cluster and may generate biased analysis results and conclusions. Therefore, the aim of this study was to quantify the variation in the prevalence of malaria between sample enumeration areas (SEAs) or clusters, the effects of cluster characteristics on the prevalence of malaria using the intra-class correlation coefficient as well as to identify significant factors that affect the prevalence of malaria using the multilevel logistic regression modelling in three major regions of Ethiopia, namely Amhara, Oromia and Southern Nations, Nationalities and Peoples' (SNNP). Dataset for three regional states extracted from the 2011 Ethiopian National Malaria Indicator Surveys (EMIS) national representative samples was used in this study. It contains 9272 sample individuals selected from these regions. Various multilevel models with random sample SEA effects were applied taking into account the survey design weights. These weights are scaled to address unequal probabilities of selection within clusters. The spatial clustering of malaria prevalence was assessed applying Getis-Ord statistic to best linear unbiased prediction values of model random effects. About 53.82 and 28.72 per cents of the sampled households in the study regions had no mosquito net and sprayed at least once within the last 12 months, respectively. The results of this study indicate that age, gender, household had mosquito nets, the dwelling has windows, source of drinking water, the two SEA-level variables, i.e. region and median altitude, were significantly related to the prevalence of malaria. After adjusting for these seven variables, about 45% of the residual variation in the prevalence of malaria in the study regions was due to systematic differences between SEAs, while the remaining 55% was due to unmeasured differences between persons or households. The estimated MOR, i.e. the unexplained SEA heterogeneity, was 4.784. This result suggests that there is high variation between SEAs in the prevalence of malaria. In addition, the 80% interval odds ratios (IORs) related to SEA-level variables contain one suggesting that the SEA variability is large in comparison with the effect of each of the variable. The multilevel logistic regression with random effects model used in this paper identified five individual / household and two SEA-level risk factors of malaria infection. Therefore, the public health policy makers should pay attentions to those significant factors, such as improving the availability of pure drinking water. Further, the findings of spatial clustering provide information to health policymakers to plan geographically targeted interventions to control malaria transmission.

Post-discharge morbidity and mortality in children admitted with severe anaemia and other health conditions in malaria-endemic settings in Africa: a systematic review and meta-analysis

Severe anaemia is associated with high in-hospital mortality among young children. In malaria-endemic areas, surviving children also remain at increased risk of mortality for several months after hospital discharge. We aimed to compare the risks of morbidity and mortality among children discharged from hospital after recovery from severe anaemia versus other health conditions in malaria-endemic settings in Africa. Following PRISMA guidelines, we searched PubMed, Scopus, Web of Science, and Cochrane Central from inception to Nov 30, 2021, without language restrictions, for prospective or retrospective cohort studies and randomised controlled trials that followed up children younger than 15 years for defined periods after hospital discharge in malaria-endemic countries in Africa. We excluded the intervention groups in trials and studies or subgroups involving children with sickle cell anaemia, malignancies, or surgery or trauma, or those reporting follow-up data that were combined with the in-hospital period. Two independent reviewers extracted the data and assessed the quality and risk of bias using the Newcastle Ottawa Scale or the Cochrane Collaboration's tool. The coprimary outcomes were all-cause death and all-cause readmissions 6 months after discharge. This study is registered with PROSPERO, CRD42017079282. Of 2930 articles identified in our search, 27 studies were included. For children who were recently discharged following hospital admission with severe anaemia, all-cause mortality by 6 months was higher than during the in-hospital period (n=5 studies; Mantel-Haenszel odds ratio 1·72, 95% CI 1·22-2·44; p=0·0020; I2=51·5%) and more than two times higher than children previously admitted without severe anaemia (n=4 studies; relative risk [RR] 2·69, 95% CI 1·59-4·53; p<0·0001; I2=69·2%). Readmissions within 6 months of discharge were also more common in children admitted with severe anaemia than in children admitted with other conditions (n=1 study; RR 3·05, 1·12-8·35; p<0·0001). Children admitted with severe acute malnutrition (regardless of severe anaemia) also had a higher 6-month mortality after discharge than those admitted for other reasons (n=2 studies; RR=3·12, 2·02-4·68; p<0·0001; I2=54·7%). Other predictors of mortality after discharge included discharge against medical advice, HIV, bacteraemia, and hypoxia. In malaria-endemic settings in Africa, children admitted to hospital with severe anaemia and severe acute malnutrition are at increased risk of mortality in the first 6 months after discharge compared with children admitted with other health conditions. Improved strategies are needed for the management of these high-risk groups during the period after discharge. Research Council of Norway and US Centers for Disease Control and Prevention.

Treatment Outcome of Severe Malaria and Associated Factors among Adults Admitted in Arba Minch General Hospital, Southern Nation Nationality and People's Region, Ethiopia.

Introduction Malaria is a protozoan disease transmitted by the bite of infected female Anopheles mosquitoes. Progression to severe and fatal disease is largely but not entirely confined to Plasmodium falciparum infections. Malaria is a major public health problem in Ethiopia despite relatively low malaria prevalence compared to most other malaria-endemic countries in Africa. In Ethiopia, a nationwide report during 2015 showed that the total number of deaths associated with malaria was 1561. Methods A retrospective cross-sectional study was conducted in Arba Minch General Hospital on February 2019. Data were collected from a patient record who was admitted with severe malaria in the past four years from Sept. 2015 to Aug. 2018. Results This study included a total of 387 patients with severe malaria. The mortality rate associated with severe malaria in the year between 2015 and 2018 at Arba Minch General Hospital was 5.7%. Comorbidity, impaired consciousness, and acidosis were significantly associated with mortality, at significant level of P < 0.05. Conclusions Comorbidity, impaired consciousness, and acidosis were found to be poor prognostic indicators for patients with severe malaria.

Malaria is a cause of iron deficiency in African children.

Malaria and iron deficiency (ID) are common and interrelated public health problems in African children. Observational data suggest that interrupting malaria transmission reduces the prevalence of ID1. To test the hypothesis that malaria might cause ID, we used sickle cell trait (HbAS, rs334), a genetic variant that confers specific protection against malaria2, as an instrumental variable in Mendelian randomization analyses. HbAS was associated with a 30% reduction in ID among children living in malaria-endemic countries in Africa (n =7,453), but not among individuals living in malaria-free areas (n =3,818). Genetically predicted malaria risk was associated with an odds ratio of 2.65 for ID per unit increase in the log incidence rate of malaria. This suggests that an intervention that halves the risk of malaria episodes would reduce the prevalence of ID in African children by 49%.

Estimating the Fraction of Severe Malaria among Malaria-Positive Children: Analysis of Household Surveys in 19 Malaria-Endemic Countries in Africa.

ABSTRACTTo date, the only robust estimates of severe malaria cases include children who present to the formal healthcare system. It is a challenge to use these data because of varying age ranges of reporting, different diagnosis techniques, surveillance methods, and healthcare utilization. This analysis examined data from 37 Demographic and Health Surveys and Malaria Indicator Surveys across 19 countries in sub-Saharan Africa collected between 2011 and 2018. The outcome of interest is a proxy indicator for severe malaria, defined as a proportion of children aged 6–59 months with at least one self-reported symptom of severe illness including loss of consciousness, rapid breathing, seizures, or severe anemia (hemoglobin < 5 g/dL) among those who were positive for malaria. The study includes a weighted descriptive, country-level analysis and a multilevel mixed-effects logistic regression model to assess the determinants of severe malaria. Among children positive for malaria across all surveys, 4.5% (95% CI: 4.1–4.8) had at least one sign or symptom of severe malaria, which was significantly associated with age, residence, wealth, and year of survey fieldwork at a P-value less than 0.05. This analysis presents a novel and an alternative approach of estimating the fraction of severe malaria cases among malaria-positive children younger than 5 years in malaria-endemic countries. Estimating severe malaria cases through population-based surveys allows countries to estimate severe malaria across time and to compare with other countries. Having a population-level estimate of severe malaria cases helps further our understanding of the burden and epidemiology of severe malaria.

Accessing the syndemic of COVID-19 and malaria intervention in Africa

BackgroundThe pandemic of the coronavirus disease 2019 (COVID-19) has caused substantial disruptions to health services in the low and middle-income countries with a high burden of other diseases, such as malaria in sub-Saharan Africa. The aim of this study is to assess the impact of COVID-19 pandemic on malaria transmission potential in malaria-endemic countries in Africa.MethodsWe present a data-driven method to quantify the extent to which the COVID-19 pandemic, as well as various non-pharmaceutical interventions (NPIs), could lead to the change of malaria transmission potential in 2020. First, we adopt a particle Markov Chain Monte Carlo method to estimate epidemiological parameters in each country by fitting the time series of the cumulative number of reported COVID-19 cases. Then, we simulate the epidemic dynamics of COVID-19 under two groups of NPIs: (1) contact restriction and social distancing, and (2) early identification and isolation of cases. Based on the simulated epidemic curves, we quantify the impact of COVID-19 epidemic and NPIs on the distribution of insecticide-treated nets (ITNs). Finally, by treating the total number of ITNs available in each country in 2020, we evaluate the negative effects of COVID-19 pandemic on malaria transmission potential based on the notion of vectorial capacity.ResultsWe conduct case studies in four malaria-endemic countries, Ethiopia, Nigeria, Tanzania, and Zambia, in Africa. The epidemiological parameters (i.e., the basic reproduction number R_0 and the duration of infection D_I) of COVID-19 in each country are estimated as follows: Ethiopia (R_0=1.57, D_I=5.32), Nigeria (R_0=2.18, D_I=6.58), Tanzania (R_0=2.47, D_I=6.01), and Zambia (R_0=2.12, D_I=6.96). Based on the estimated epidemiological parameters, the epidemic curves simulated under various NPIs indicated that the earlier the interventions are implemented, the better the epidemic is controlled. Moreover, the effect of combined NPIs is better than contact restriction and social distancing only. By treating the total number of ITNs available in each country in 2020 as a baseline, our results show that even with stringent NPIs, malaria transmission potential will remain higher than expected in the second half of 2020.ConclusionsBy quantifying the impact of various NPI response to the COVID-19 pandemic on malaria transmission potential, this study provides a way to jointly address the syndemic between COVID-19 and malaria in malaria-endemic countries in Africa. The results suggest that the early intervention of COVID-19 can effectively reduce the scale of the epidemic and mitigate its impact on malaria transmission potential.

Surveillance of Antimalarial Resistance Pfcrt, Pfmdr1, and Pfkelch13 Polymorphisms in African Plasmodium falciparum imported to Shandong Province, China

Antimalarial drug resistance is a major public health problem in China. From 2012 to 2015, more than 75% of malaria cases in Shandong Province were P. falciparum returned from Africa. However, molecular marker polymorphisms of drug resistance in imported P. falciparum cases have not been evaluated. In this study, we analyzed polymorphisms of the Pfcrt, Pfmdr1, and Pfkelch13 genes in 282 P. falciparum cases returned from Africa to Shandong between 2012 and 2015. Among the isolates, polymorphisms were detected in codons 74–76 of Pfcrt and 86, 184, 1246 of Pfmdr1, among which K76T (36.6%) and Y184F (60.7%) were the most prevalent, respectively. Six Pfcrt haplotypes and 11 Pfmdr1 haplotypes were identified and a comparison was made on the prevalence of haplotypes among East Africa, West Africa, Central Africa and South Africa. One synonymous and 9 nonsynonymous mutations in Pfkelch13 were detected in the isolates (4.6%), among which a candidate artemisinin (ART) resistance mutation P553L was observed. The study establishes fundamental data for detection of chloroquine resistance (CQR) and ART resistance with molecular markers of the imported P. falciparum in China, and it also enriches the genetic data of antimalarial resistance for the malaria endemic countries in Africa.

Economic burden of malaria and predictors of cost variability to rural households in south-central Ethiopia.

BackgroundWhile recognizing the recent remarkable achievement in the global malaria reduction, the disease remains a challenge to the malaria endemic countries in Africa. Beyond the huge health consequence of malaria, policymakers need to be informed about the economic burden of the disease to the households. However, evidence on the economic burden of malaria in Ethiopia is scanty. The aims of this study were to estimate the economic burden of malaria episode and to identify predictors of cost variability to the rural households.MethodsA prospective costing approach from a household perspective was employed. A total of 190 malaria patients were enrolled to the study from three health centers and nine health posts in Adami Tullu district in south-central Ethiopia, in 2015. Primary data were collected on expenditures due to malaria, forgone working days because of illness, socioeconomic and demographic situation, and households’ assets. Quantile regression was applied to predict factors associated with the cost variation. Socioeconomic related inequality was measured using concentration index and concentration curve.ResultsThe median cost of malaria per episode to the household was USD 5.06 (IQR: 2.98–8.10). The direct cost accounted for 39%, while the indirect counterpart accounted for 61%. The history of malaria in the last six months and the level of the facility visited in the health system predominantly influenced the direct cost. The indirect cost was mainly influenced by the availability of antimalarial drugs in the health facility. The concentration curve and the concentration index for direct cost indicate significant pro-rich inequality. Plasmodium falciparum is significantly more costly for households compared to Plasmodium vivax.ConclusionThe economic burden of malaria to the rural households in Ethiopia was substantial—mainly to the poor—indicating that reducing malaria burden could contribute to the poverty reduction as well.

Cerebrospinal fluid markers to distinguish bacterial meningitis from cerebral malaria in children.

Background. Few hospitals in high malaria endemic countries in Africa have the diagnostic capacity for clinically distinguishing acute bacterial meningitis (ABM) from cerebral malaria (CM). As a result, empirical use of antibiotics is necessary. A biochemical marker of ABM would facilitate precise clinical diagnosis and management of these infections and enable rational use of antibiotics. Methods. We used label-free protein quantification by mass spectrometry to identify cerebrospinal fluid (CSF) markers that distinguish ABM (n=37) from CM (n=22) in Kenyan children. Fold change (FC) and false discovery rates (FDR) were used to identify differentially expressed proteins. Subsequently, potential biomarkers were assessed for their ability to discriminate between ABM and CM using receiver operating characteristic (ROC) curves. Results. The host CSF proteome response to ABM ( Haemophilusinfluenza and Streptococcuspneumoniae) is significantly different to CM. Fifty two proteins were differentially expressed (FDR<0.01, Log FC≥2), of which 83% (43/52) were upregulated in ABM compared to CM. Myeloperoxidase and lactotransferrin were present in 37 (100%) and 36 (97%) of ABM cases, respectively, but absent in CM (n=22). Area under the ROC curve (AUC), sensitivity, and specificity were assessed for myeloperoxidase (1, 1, and 1; 95% CI, 1-1) and lactotransferrin (0.98, 0.97, and 1; 95% CI, 0.96-1). Conclusion. Myeloperoxidase and lactotransferrin have a high potential to distinguish ABM from CM and thereby improve clinical management. Their validation requires a larger cohort of samples that includes other bacterial aetiologies of ABM.

Cerebrospinal fluid markers to distinguish bacterial meningitis from cerebral malaria in children

Background . Few hospitals in high malaria endemic countries in Africa have the diagnostic capacity for clinically distinguishing acute bacterial meningitis (ABM) from cerebral malaria (CM). As a result, empirical use of antibiotics is necessary. A biochemical marker of ABM would facilitate precise clinical diagnosis and management of these infections and enable rational use of antibiotics. Methods. We used label-free protein quantification by mass spectrometry to identify cerebrospinal fluid (CSF) markers that distinguish ABM (n=37) from CM (n=22) in Kenyan children. Fold change (FC) and false discovery rates (FDR) were used to identify differentially expressed proteins. Subsequently, potential biomarkers were assessed for their ability to discriminate between ABM and CM using receiver operating characteristic (ROC) curves. Results. The host CSF proteome response to ABM ( Haemophilus influenza and Streptococcus pneumoniae) is significantly different to CM. Fifty two proteins were differentially expressed (FDR<0.01, Log FC≥2), of which 83% (43/52) were upregulated in ABM compared to CM. Myeloperoxidase and lactotransferrin were present in 37 (100%) and 36 (97%) of ABM cases, respectively, but absent in CM (n=22). Area under the ROC curve (AUC), sensitivity, and specificity were assessed for myeloperoxidase (1, 1, and 1; 95% CI, 1-1) and lactotransferrin (0.98, 0.97, and 1; 95% CI, 0.96-1). Conclusion. Myeloperoxidase and lactotransferrin have a high potential to distinguish ABM from CM and thereby improve clinical management. Their validation requires a larger cohort of samples that includes other bacterial aetiologies of ABM.

A study on the epidemiological characteristics and infectious forecast model of malaria at Guangzhou Airport among Chinese returnees from Africa

BackgroundCross-border malaria transmission in China is a major component of Chinese imported malaria cases. Such cases mostly are travellers returning from malaria endemic countries in Africa. By investigating malaria infectious status among Chinese worker in Africa, this study analysed the malaria risk factors, in order to establish infectious forecast model.MethodsChinese returnees data from Africa were collected at Guangzhou Baiyun International Airport, Guangzhou, China between August 2015 and March 2016 and were included in the cross-sectional and retrospective survey.ResultsA total of 1492 respondents were included in the study with the majority consisting of junior middle school educated male. Most of them are manual and technical workers hired by companies, with average of 37.04 years of age. Overall malaria incidence rate of the population was 8.98% (134/1492), and there were no significant differences regarding age, gender, occupation, or team. Forecast model was developed on the basis of malaria risk factors including working country, local ecological environment type, work duration and intensity of mosquito bite prevention.ConclusionsThe survey suggested that malaria incidence was high among Chinese travellers who had worked in Africa countries of heavy malaria burden. Further research on the frequency and severity of clinical episodes among Chinese travellers having worked in Africa is needed.

Cerebrospinal fluid markers to distinguish bacterial meningitis from cerebral malaria in children

Background. Few hospitals in high malaria endemic countries in Africa have the diagnostic capacity for clinically distinguishing acute bacterial meningitis (ABM) from cerebral malaria (CM). As a result, empirical use of antibiotics is necessary. A biochemical marker of ABM would facilitate precise clinical diagnosis and management of these infections and enable rational use of antibiotics. Methods. We used label-free protein quantification by mass spectrometry to identify cerebrospinal fluid (CSF) markers that distinguish ABM (n=37) from CM (n=22) in Kenyan children. Fold change (FC) and false discovery rates (FDR) were used to identify differentially expressed proteins. Subsequently, potential biomarkers were assessed for their ability to discriminate between ABM and CM using receiver operating characteristic (ROC) curves. Results. The host CSF proteome response to ABM (Haemophilus influenza and Streptococcus pneumoniae) is significantly different to CM. Fifty two proteins were differentially expressed (FDR&lt;0.01, Log FC≥2), of which 83% (43/52) were upregulated in ABM compared to CM. Myeloperoxidase and lactotransferrin were present in 37 (100%) and 36 (97%) of ABM cases, respectively, but absent in CM (n=22). Area under the ROC curve (AUC), sensitivity, and specificity were assessed for myeloperoxidase (1, 1, and 1; 95% CI, 1-1) and lactotransferrin (0.98, 0.97, and 1; 95% CI, 0.96-1). Conclusion. Myeloperoxidase and lactotransferrin have a high potential to distinguish ABM from CM and thereby improve clinical management. Their validation requires a larger cohort of samples that includes other bacterial aetiologies of ABM.

Two years post affordable medicines facility for malaria program: availability and prices of anti-malarial drugs in central Ghana

BackgroundThe Affordable Medicines Facility for malaria (AMFm) Program was a subsidy aimed at artemisinin-based combination therapies (ACTs) in order to increase availability, affordability, and market share of ACTs in 8 malaria endemic countries in Africa. The WHO supervised the manufacture of the subsidized products, named them Quality Assured ACTs (QAACT) and printed a Green Leaf Logo on all QAACT packages. Ghana began to receive the subsidized QAACTs in 2010.MethodsA cross-sectional stock survey was conducted at 63 licensed chemical shops (LCS) and private pharmacies in two districts of the Brong-Ahafo region of Ghana to determine the availability and price of all anti-malarial treatments. Drug outlets were visited over a 3-weeks period in October and November of 2014, about 2 years after the end of AMFm program.ResultsAt least one QAACT was available in 88.9% (95% CI 80.9% – 96.8%) of all drug outlets with no difference between urban and rural locations. Non-Assured ACTs (NAACT) were significantly more available in urban drug outlets [75.0% availability (95% CI 59.1% – 90.9%)] than in rural drug outlets [16.1% availability (95% CI 2.4% – 29.9%)]. The top selling product was Artemether Lumefantrine with the Green Leaf Logo, a QAACT. There was a significant difference in the mean price of a QAACT [$1.04 USD (95% CI $0.98 – $1.11)], and the mean price of a NAACT in both the urban and rural areas [$2.46 USD (95% CI $2.11 – $2.81)]. There was no significant difference in the price of any product that was available in urban and rural settingsConclusionAbout 2 years after the AMFm program, subsidized QAACTs in Ghana were widely available and more affordable than NAACTs in the Kintampo North District and Kintampo South Municipality of Ghana. The AMFm program appeared to have mostly succeeded in making QAACTs available and affordable.

Residual risk of transfusion-transmitted malaria infection in a malaria endemic sub-Saharan African setting

BackgroundIn Cameroon, as in many malaria endemic countries in Africa, blood donors are not routinely screened for Plasmodium infection that potentially could lead to severe malaria in some recipients. This study aimed at defining the prevalence of malaria among blood donors in Cameroon, and determining the risk of transfusion-transmitted malaria (TTM) following a single unit of blood transfusion.MethodsA total of 250 blood donors were recruited at the Douala General Hospital in Cameroon. Blood samples were tested for the presence of Plasmodium by using a rapid diagnostic test (RDT), and by thin and thick blood smear microscopy. A mathematical model was performed to calculate individual risk and to estimate population incidence rates of TTM per year. Different data sources were used in the sensitivity analysis prior to estimation of malaria transfusion risk.ResultsMore than half (96.8%) of all blood donors were men, and the mean age of the donors was 28.5 (SD = 8.9) years. Infected volunteer donors represented 2.80% while infected family-replacement donors comprised 97.20%. The prevalence of P. falciparum infection was 12.0%, and the population mean parasite density was 6,056 (95% CI: 4,542–8,076) parasites/μL. The individual median residual risk of TTM was 5.59 per 10,000 or 2.64 per 1,000 units of blood transfused every year in Douala or Cameroon, respectively.ConclusionsThis study confirms the presence of P. falciparum as one of the most prevalent TTIs in the region. The residual risk of TTM is high among blood recipients, urging to conduct in malaria-endemic areas a cost-benefit analysis of systematically screening blood units for malaria parasites before transfusion versus systematically treating the recipient after transfusion.

Assessing the availability of LLINs for continuous distribution through routine antenatal care and the Expanded Programme on Immunizations in sub-Saharan Africa.

BackgroundIn addition to mass distribution campaigns, the World Health Organization (WHO) recommends the continuous distribution of long-lasting insecticidal nets (LLINs) to all pregnant women attending antenatal care (ANC) and all infants attending the Expanded Programme on Immunization (EPI) services in countries implementing mosquito nets for malaria control. Countries report LLIN distribution data to the WHO annually. For this analysis, these data were used to assess policy and practice in implementing these recommendations and to compare the numbers of LLINs available through ANC and EPI services with the numbers of women and children attending these services.MethodsFor each reporting country in sub-Saharan Africa, the presence of a reported policy for LLIN distribution through ANC and EPI was reviewed. Prior to inclusion in the analysis the completeness of data was assessed in terms of the numbers of LLINs distributed through all channels (campaigns, EPI, ANC, other). For each country with adequate data, the numbers of LLINs reportedly distributed by national programmes to ANC was compared to the number of women reportedly attending ANC at least once; the ratio between these two numbers was used as an indicator of LLIN availability at ANC services. The same calculations were repeated for LLINs distributed through EPI to produce the corresponding LLIN availability through this distribution channel.ResultsAmong 48 malaria-endemic countries in Africa, 33 malaria programmes reported adopting policies of ANC-based continuous distribution of LLINs, and 25 reported adopting policies of EPI-based distribution. Over a 3-year period through 2012, distribution through ANC accounted for 9 % of LLINs distributed, and LLINs distributed through EPI accounted for 4 %. The LLIN availability ratios achieved were 55 % through ANC and 34 % through EPI. For 38 country programmes reporting on LLIN distribution, data to calculate LLIN availability through ANC and EPI was available for 17 and 16, respectively.ConclusionsThese continuous LLIN distribution channels appear to be under-utilized, especially EPI-based distribution. However, quality data from more countries are needed for consistent and reliable programme performance monitoring. A greater focus on routine data collection, monitoring and reporting on LLINs distributed through both ANC and EPI can provide insight into both strengths and weaknesses of continuous distribution, and improve the effectiveness of these delivery channels.

Assessment of the usage and effectiveness of intermittent preventive treatment and insecticide-treated nets on the indicators of malaria among pregnant women attending antenatal care in the Buea Health District, Cameroon.

BackgroundMalaria in pregnancy is an immense public health problem with at least 50 million pregnant women living in malaria endemic areas. To prevent malaria and its complications in pregnancy the World Health Organization recommends the use of intermittent preventive treatment sulfadoxine–pyrimethamine (IPTp-SP), the use of insecticide-treated nets (ITNs), and effective case management. In most malaria endemic countries in Africa, 40 % of pregnant women sleep under ITNs. In Cameroon, about 90 % of pregnant women receive the first dose of SP, while 64 % take the complete dose. Following the 2011 mass-campaign of free distribution of ITNs coupled with routine ANC distribution of ITN and adoption of IPTp in Cameroon, little has been done to assess the effectiveness of both interventions outside of Yaoundé, the capital city. This study sought to assess the usage and effectiveness of IPTp-SP and ITNs on malaria in pregnancy.MethodsThe research was a cross-sectional hospital-based study that included 410 pregnant women attending antenatal clinics in the Buea Health District. Capillary blood samples were collected to check malaria parasite by microscopy and haemoglobin levels by microhaematocrit technique.ResultsA prevalence of 13.4 and 41.7 % was detected for malaria and anaemia, respectively. The Overall coverage of ITN was 32.4 % while that of ITPp was 63.2 %. Malaria prevalence was least (7.2 %) amongst women using both IPTp-SP and ITN while those with no intervention had the highest malaria prevalence of 18.6 % (χ2 = 6.188; P = 0.103). Of the women with malaria, 12.73 % were using ITN and had taken at least one dose of SP, 38.18 % had taken at least one dose IPTp only, 10.91 % were using only ITN and 38.18 % were not using any preventive measure. There was a difference in anaemia status within the different intervention groups (χ2 = 8.673; P = 0.034). Pregnant women using both interventions were less associated to malaria (OR = 0.341, 95 % CI = 0.138–0.841) compared to those using only one control method.ConclusionRepeated doses of SP in combination with ITN use are effective in reducing malaria parasitaemia and improving haemoglobin level of pregnant women.

Culture-adapted Plasmodium falciparum isolates from UK travellers: in vitro drug sensitivity, clonality and drug resistance markers

BackgroundThe screening of lead compounds against in vitro parasite cultures is an essential step in the development of novel anti-malarial drugs, but currently relies on laboratory parasite lines established in vitro during the last century. This study sought to establish in continuous culture a series of recent Plasmodium falciparum isolates to represent the current parasite populations in Africa, all of which are now exposed to artemisinin combination therapy.MethodsPre-treatment P. falciparum isolates were obtained in EDTA, and placed into continuous culture after sampling of DNA. One post-treatment blood sample was also collected for each donor to monitor parasite clonality during clearance in vivo. IC50 estimates were obtained for 11 anti-malarial compounds for each established parasite line, clonal multiplicity measured in vivo and in vitro, and polymorphic sites implicated in parasite sensitivity to drugs were investigated at the pfmdr1, pfcrt, pfdhfr, pfdhps and pfap2mu loci before and after treatment, and in the cultured lines.ResultsPlasmodium falciparum isolates from seven malaria patients with recent travel to three West African and two East African countries were successfully established in long-term culture. One of these, HL1211, was from a patient with recrudescent parasitaemia 14 days after a full course of artemether-lumefantrine. All established culture lines were shown to be polyclonal, reflecting the in vivo isolates from which they were derived, and at least two lines reliably produce gametocytes in vitro. Two lines displayed high chloroquine IC50 estimates, and carried the CVIET haplotype at codons 72–76, whereas the remaining five lines carried the CVMNK haplotype and were sensitive in vitro. All were sensitive to the endoperoxides dihydroartemisinin and OZ277, but IC50 estimates for lumefantrine varied, with the least sensitive parasites carrying pfmdr1 alleles encoding Asn at codon 86.ConclusionsThis study describes the establishment in continuous culture, in vitro drug sensitivity testing and molecular characterization of a series of multiclonal P. falciparum isolates taken directly from UK malaria patients following recent travel to various malaria-endemic countries in Africa. These “HL” isolates are available as an open resource for studies of drug response, antigenic diversity and other aspects of parasite biology.

How Well Are Malaria Maps Used to Design and Finance Malaria Control in Africa?

IntroductionRational decision making on malaria control depends on an understanding of the epidemiological risks and control measures. National Malaria Control Programmes across Africa have access to a range of state-of-the-art malaria risk mapping products that might serve their decision-making needs. The use of cartography in planning malaria control has never been methodically reviewed.Materials and MethodsAn audit of the risk maps used by NMCPs in 47 malaria endemic countries in Africa was undertaken by examining the most recent national malaria strategies, monitoring and evaluation plans, malaria programme reviews and applications submitted to the Global Fund. The types of maps presented and how they have been used to define priorities for investment and control was investigated.Results91% of endemic countries in Africa have defined malaria risk at sub-national levels using at least one risk map. The range of risk maps varies from maps based on suitability of climate for transmission; predicted malaria seasons and temperature/altitude limitations, to representations of clinical data and modelled parasite prevalence. The choice of maps is influenced by the source of the information. Maps developed using national data through in-country research partnerships have greater utility than more readily accessible web-based options developed without inputs from national control programmes. Although almost all countries have stratification maps, only a few use them to guide decisions on the selection of interventions allocation of resources for malaria control.ConclusionThe way information on the epidemiology of malaria is presented and used needs to be addressed to ensure evidence-based added value in planning control. The science on modelled impact of interventions must be integrated into new mapping products to allow a translation of risk into rational decision making for malaria control. As overseas and domestic funding diminishes, strategic planning will be necessary to guide appropriate financing for malaria control.