Malaria Morbidity Research Articles

Home fortification of foods with multiple micronutrient powders for health and nutrition in children under two years of age.

Home fortification of foods with multiple micronutrient powders for health and nutrition in children under two years of age.

Oxidative and nitrosative stresses in cerebral malaria: can we target them to avoid a bad prognosis?

There is currently a global effort to reduce malaria morbidity and mortality. However, malaria still results in the deaths of thousands of people every year. Malaria is caused by Plasmodium spp., parasites transmitted through the bite of an infected female Anopheles mosquito. Treatment timing plays a decisive role in reducing mortality and sequelae associated with the severe forms of the disease such as cerebral malaria (CM). The available antimalarial therapy is considered effective but parasite resistance to these drugs has been observed in some countries. Antimalarial drugs act by increasing parasite lysis, especially through targeting oxidative stress pathways. Here we discuss the roles of reactive oxygen species and reactive nitrogen intermediates in CM as a result of host-parasite interactions. We also present evidence of the potential contribution of oxidative and nitrosative stress-based antimalarial drugs to disease treatment and control.

The duration of chemoprophylaxis against malaria after treatment with artesunate-amodiaquine and artemether-lumefantrine and the effects of pfmdr1 86Y and pfcrt 76T: a meta-analysis of individual patient data

BackgroundThe majority of Plasmodium falciparum malaria cases in Africa are treated with the artemisinin combination therapies artemether-lumefantrine (AL) and artesunate-amodiaquine (AS-AQ), with amodiaquine being also widely used as part of seasonal malaria chemoprevention programs combined with sulfadoxine-pyrimethamine. While artemisinin derivatives have a short half-life, lumefantrine and amodiaquine may give rise to differing durations of post-treatment prophylaxis, an important additional benefit to patients in higher transmission areas.MethodsWe analyzed individual patient data from 8 clinical trials of AL versus AS-AQ in 12 sites in Africa (n = 4214 individuals). The time to PCR-confirmed reinfection after treatment was used to estimate the duration of post-treatment protection, accounting for variation in transmission intensity between settings using hidden semi-Markov models. Accelerated failure-time models were used to identify potential effects of covariates on the time to reinfection. The estimated duration of chemoprophylaxis was then used in a mathematical model of malaria transmission to determine the potential public health impact of each drug when used for first-line treatment.ResultsWe estimated a mean duration of post-treatment protection of 13.0 days (95% CI 10.7–15.7) for AL and 15.2 days (95% CI 12.8–18.4) for AS-AQ overall. However, the duration varied significantly between trial sites, from 8.7–18.6 days for AL and 10.2–18.7 days for AS-AQ. Significant predictors of time to reinfection in multivariable models were transmission intensity, age, drug, and parasite genotype. Where wild type pfmdr1 and pfcrt parasite genotypes predominated (<=20% 86Y and 76T mutants, respectively), AS-AQ provided ~ 2-fold longer protection than AL. Conversely, at a higher prevalence of 86Y and 76T mutant parasites (> 80%), AL provided up to 1.5-fold longer protection than AS-AQ. Our simulations found that these differences in the duration of protection could alter population-level clinical incidence of malaria by up to 14% in under-5-year-old children when the drugs were used as first-line treatments in areas with high, seasonal transmission.ConclusionChoosing a first-line treatment which provides optimal post-treatment prophylaxis given the local prevalence of resistance-associated markers could make a significant contribution to reducing malaria morbidity.

Analysis of trends of malaria from 2010 to 2017 in Boricha District, Southern Ethiopia

BackgroundEthiopia has made a significant progress of malaria control. Currently, the country has adopted and is implementing the World Health Organization very ambitious, but achievable, malaria elimination plan through extensive efforts. The regular evaluation of its performance is vital for plausible improvement. Thus, the aim of this study was to determine the trends of malaria infection in Boricha district, Southern Ethiopia.MethodsA retrospective study was conducted in all health facilities of the district. All malaria cases registered during 2010 to 2017 were reviewed to determine the trends of malaria morbidity. EpiData 3.1 was used for data entry and data were analysed using SPSS version 20.0.ResultsA total of 135,607 malaria suspects were diagnosed using microscopy and rapid diagnostic test over the last 8 years, of which 29,554 (21.8%) were confirmed positive cases. Plasmodium falciparum, Plasmodium vivax and mixed infections (both species) accounted for 56.3%, 38.4% and 5.2% of cases, respectively. Except in 2013 and 2014, Plasmodium falciparum was the dominant species over P. vivax. Of the total confirmed cases 51.6% were adults (≥ 15 years) followed by 24.5% of 5–14 years, and 23.9% of under 5 years. In general, malaria morbidity was significantly reduced over the last 8 years. The positivity rate declined from 54.6% to 5% during 2010 to 2017, and the case incidence rate per 1000 population at risk also declined from 18.9 to 2.2 during the same period. Malaria was reported in all months of the year, with peaks in November, followed by September and July. Malaria transmission has strong association with season (x2 = 303.955, df = 22, p < 0.0001).ConclusionIn general, a significant reduction of malaria morbidity was observed over the past 8 years. However, further investigation using advanced diagnostic tools is vital to determine the level of sub-microscopic infections to guide the elimination plan. In addition, eco-epidemiological analysis at fine-scale level is essential to devise area-specific interventions.

Prevalence of Plasmodium falciparum field isolates with deletions in histidine-rich protein 2 and 3 genes in context with sub-Saharan Africa and India: a systematic review and meta-analysis

BackgroundIn 2017, nearly 80% of malaria morbidity and mortality occurred in sub-Saharan African (SSA) countries and India. Rapid diagnostic tests (RDTs), especially those targeting histidine-rich protein 2 (PfHRP2) of Plasmodium falciparum, have become an important diagnostic tool in these malaria-endemic areas. However, the chances of RDT-oriented successful treatment are increasingly jeopardized by the appearance of mutants with deletions in pfhrp2 and pfhrp3 genes. This systematic review and meta-analysis determines the prevalence of field P. falciparum isolates with deletion in pfhrp2 and/or pfhrp3 genes and their proportion among false-negative results in the PfHRP2-based RDTs in SSA and India.MethodsEight electronic databases were used for searching potentially relevant publications for the systematic review analysis, wherein the main methodological aspects of included studies were analysed and some missing links in the included studies were identified.ResultsA total of 19 studies were included, 16 from SSA and 3 from India. The pooled prevalence of pfhrp2 deletions was 8 and 5% while 16 and 4% for pfhrp3 gene deletions in Africa and India, respectively. The pooled proportion of pfhrp2 gene deletions found among false negative PfHRP2-based RDTs results was about 27.0 and 69.0% in Africa and India, respectively.ConclusionsThis review study indicates a relatively high proportion of both pfhrp2/3 genes deletions in P. falciparum isolates and among false-negative malaria cases using PfHRP2-based RDT results in SSA and India. Recently the deletions in pfhrp2/3 genes have also been reported from two African countries (Nigeria and Sudan). This review emphasizes the importance of more extensive studies and standardization of studies addressing the pfhrp2/3 gene deletions in malarious areas.

Paediatric morbidity and mortality in Sierra Leone. Have things changed after the 2014/2015 Ebola outbreak?

Background:Sierra Leone was severely affected by the 2014/2015 Ebola outbreak which is likely to have had longer term repercussions on the health system including on paediatric morbidity and mortality. We thus assessed under-five morbidity and mortality for malaria, acute respiratory Infections (ARI)/pneumonia, watery diarrhoea and measles during the post-Ebola period in Sierra Leone and compared this with the pre- and intra-Ebola periods. Methods:This was a retrospective cross-sectional study using program data from the District Health Information system (DHIS2) and sourced from 14 districts in Sierra Leone. It included under-five children from 1,250 health facilities country-wide. Study periods included: before (June 1 st, 2013-April 30 th, 2014); during (June 1 st, 2014-April 30 th, 2015); and after Ebola (June 1 st, 2016-April 30 th, 2017). Results:Malaria, ARI/pneumonia and diarrhoea consultations declined during Ebola but recovered to pre-Ebola levels in the post-Ebola period. During the post-Ebola period, there was a highly significant reduction in case-fatality for the first three morbidities compared to the pre-Ebola period ( P<0.0001). Average number of measles cases increased from 48/month in the pre-Ebola period to 568/month (12-fold increase) post-Ebola. Although there was no difference in measles case-fatality between the pre- and post-Ebola periods, case-fatality post-Ebola was significantly lower than during Ebola (Relative Risk: 0.05, 95% confidence interval 0.02-0.15, P<0.0001). Conclusions:Consultations for under-five children at health facilities in Sierra Leone recovered to pre-Ebola levels and case-fatality for common childhood illnesses declined significantly. This is a change for the better. However, the high level of reported measles cases in the post-Ebola period indicates gaps in immune status and needs focused attention.

Effect of Free Healthcare Policy for Children under Five Years Old on the Incidence of Reported Malaria Cases in Burkina Faso by Bayesian Modelling: "Not only the Ears but also the Head of the Hippopotamus".

Burkina Faso has recently implemented an additional strategy, the free healthcare policy, to further improve maternal and child health. This policy targets children under five who bear the brunt of the malaria scourge. The effects of the free-of-charge healthcare were previously assessed in women but not in children. The present study aims at filling this gap by assessing the effect of this policy in children under five with a focus on the induced spatial and temporal changes in malaria morbidity. We used a Bayesian spatiotemporal negative binomial model to investigate the space–time variation in malaria incidence in relation to the implementation of the policy. The analysis relied on malaria routine surveillance data extracted from the national health data repository and spanning the period from January 2013 to December 2018. The model was adjusted for meteorological and contextual confounders. We found that the number of presumed and confirmed malaria cases per 1000 children per month increased between 2013 and 2018. We further found that the implementation of the free healthcare policy was significantly associated with a two-fold increase in the number of tested and confirmed malaria cases compared with the period before the policy rollout. This effect was, however, heterogeneous across the health districts. We attributed the rise in malaria incidence following the policy rollout to an increased use of health services combined with an increased availability of rapid tests and a higher compliance to the “test and treat” policy. The observed heterogeneity in the policy effect was attributed to parallel control interventions, some of which were rolled out at different paces and scales. Our findings call for a sustained and reinforced effort to test all suspected cases so that, alongside an improved case treatment, the true picture of the malaria scourge in children under five emerges clearly (see the hippopotamus almost entirely).

Feasibility of Malaria Elimination in Ethiopia.

The problem of malaria is very severe in Ethiopia where it has been the major cause of illness and death for many years. The purpose of this review article is to assess the feasibility of malaria elimination in Ethiopia. To compile this review article, different relevant research articles related to the topic from open access journals were searched using different searching engines such as Google scholar, Science direct, and Pub Med using different key words and phrases. Based on review of the literature, Ethiopia has been trying to control and eliminate malaria for more than 60 years. To assess feasibility of malaria elimination, the WHO assessment tools/recommendations for elimination of malaria were used. Based on WHO parameters, the country has achieved remarkable progress on the fight against malaria during the most recent decades. Malaria morbidity and mortality have been reduced dramatically with intensive use of insecticide residual spray, long lasting insecticide treated nets, chemotherapies, improved diagnosis and case management, improved quality of laboratories, continued support from malaria partners, and political commitment of the Ethiopian government towards malaria prevention and control. Hence, the past achievements and current activities, have led to consider the possibility of malaria elimination in Ethiopia at least by 2030 or beyond. Considering the triumphs achieved so far and the current undertaking efforts, malaria could possibly be eliminated from Ethiopia once and for all.

Advancing Malaria Prevention and Control in Africa Through the Peace Corps-US President's Malaria Initiative Partnership.

BackgroundPeace Corps is a US government volunteer service agency which provides trained Volunteers to assist host countries in addressing critical development challenges at the community level. The US President’s Malaria Initiative provides technical expertise and financial resources to reduce malaria morbidity and mortality in focus countries in sub-Saharan Africa.ObjectiveWe aim to describe the nature of the collaboration between Peace Corps and President’s Malaria Initiative (PMI) and highlight examples of the partnership in select countries.MethodsWe conducted an analysis of retrospective data obtained from Peace Corps and PMI for the years 2014–2019.ResultsVolunteers were able to learn about and work on malaria prevention and control with PMI in three key ways: a malaria-specific training program for staff and Volunteers; malaria-focused small grants; and extension of Volunteer assignments for a third year to support malaria projects. Successful Peace Corps projects supported by PMI, at the community level, were highlighted, with a focus on Rwanda, Benin, Zambia, Madagascar, and Senegal. In Fiscal Year 2019, 1408 Volunteers contributed to malaria prevention activities in 18 Peace Corps programs across Africa, of which 15 were PMI focus countries. While the majority of documented work by Volunteers has involved social and behavior change, there were many other ways to partner with PMI staff.ConclusionEach of the proven interventions that PMI supports for malaria prevention and control may have a role for Volunteer involvement. Combined with the technical expertise and the relationships that PMI staff have with national-level counterparts in PMI focus countries, the continued collaboration between Peace Corps and PMI can accelerate the fight against malaria.

Design of antimalarial agents based on pyrimidine derivatives as methionine aminopeptidase 1b inhibitor: Molecular docking, quantitative structure activity relationships, and molecular dynamics simulation studies

AbstractMalaria is a parasitic disease mainly caused by Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae, and Plasmodium ovale and rarely by animal plasmodium such as Plasmodium knowlesi. Despite the worldwide endorsement of eradicating malaria, the mortality and morbidity of malaria is still high, especially in children of resource‐poor regions of the world. In the current study, a series of 2‐pyridyl pyrimidine derivatives with P. falciparum methionine aminopeptidase 1b (MA1b) inhibitory activity were subjected to quantitative structure, relationship activities, molecular docking, and molecular dynamics simulation to identify the ideal physicochemical characteristics and the drug–receptor interactions of potential antimalarial compounds. The structures were built using HyperChem. A docking study was performed using AutoDock. The obtained quantitative structure activity relationships model has showed that the descriptors MLOGP, E2p, Mor24u, PW2, and H8m mainly affect the antimalarial activity of the series of ligands. The residues His 277, Fe 370, Asp 240, Trp 320, and Tyr 260 of MA1b play a very important role in the drug–enzyme interaction by creating hydrogen bond, π‐cation, and π‐π interactions. To give a complete impression about the pyrimidine derivatives, compound 7 was subjected to 1,000 ps molecular dynamics (MD) simulations. The best structure based on our study was suggested for a future new drug with potential antimalarial compounds.

Vector dynamics predicts transmission dynamics: a simple, realistic and sensible approach for measuring malaria endemicity.

Entomological indicators such as vector density, distribution, biology and bionomics and their vectorial attributes are important parameters for measuring the pattern and intensity of malaria transmission. Although published articles provide evidence for the existence of associations between entomological indices and malaria transmission dynamics, none of them is able to establish a strong correlation. In order to address this issue, the present study aims to assess how malaria transmission is influenced and can be predicted by local major vector dynamics. We carried out an entomological assessment of major Anopheline vector abundance, habit/habitat, resting and feeding behavior, infectivity rates, and other entomological parameters. Results suggest that malaria transmission was correlated with a vector control intervention and non-intervention scenario in a high endemic region of Kalahandi district of Odisha, India. Amongst all indices, infective anthropophagic vectors established a strong positive correlation with malaria morbidity in comparison to infective or anthropophagic vector species during both the study periods. Though other entomological parameters influenced the transmission intensity, little quantifiable association was detected among study sites. This study provides strong baseline evidence of an association between entomological indices and malaria transmission dynamics, which could be used as an early warning system for outbreak prediction.

Paediatric morbidity and mortality in Sierra Leone. Have things changed after the 2014/2015 Ebola outbreak?

Background: Sierra Leone was severely affected by the 2014/2015 Ebola outbreak which is likely to have had longer term repercussions on the health system including on paediatric morbidity and mortality. We thus assessed under-five morbidity and mortality for malaria, acute respiratory Infections (ARI)/pneumonia, watery diarrhoea and measles during the post-Ebola period in Sierra Leone and compared this with the pre- and intra-Ebola periods. Methods: This was a retrospective cross-sectional study using program data from the District Health Information system (DHIS2) and sourced from 14 districts in Sierra Leone. It included under-five children from 1,250 health facilities country-wide. Study periods included: before (June 1 st, 2013-April 30 th, 2014); during (June 1 st, 2014-April 30 th, 2015); and after Ebola (June 1 st, 2016-April 30 th, 2017). Results: Malaria, ARI/pneumonia and diarrhoea consultations declined during Ebola but recovered to pre-Ebola levels in the post-Ebola period. During the post-Ebola period, there was a highly significant reduction in case-fatality for the first three morbidities compared to the pre-Ebola period ( P<0.0001). Average number of measles cases increased from 48/month in the pre-Ebola period to 568/month (12-fold increase) post-Ebola. Although there was no difference in measles case-fatality between the pre- and post-Ebola periods, case-fatality post-Ebola was significantly lower than during Ebola (Relative Risk: 0.05, 95% confidence interval 0.02-0.15, P<0.0001). Conclusions: Consultations for under-five children at health facilities in Sierra Leone recovered to pre-Ebola levels and case-fatality for common childhood illnesses declined significantly. This is a change for the better. However, the high level of reported measles cases in the post-Ebola period indicates gaps in immune status and needs focused attention.

Rolling back malaria in Africa - challenges and opportunities to winning the elimination battle.

A high-level review was conducted of the literature pertaining to the challenges and opportunities for eliminating malaria on the African continent. Although malaria mortality and morbidity are on the decline, the disease remains one of public health importance. Africa has invariably borne the brunt of the disease, recording the highest number of cases and deaths. However, with greater emphasis being placed on the disease by the international community, partnerships have developed to boost malaria elimination efforts on the continent. One such initiative is the Roll Back Malaria (RBM) partnership which aims to facilitate malaria elimination through increasing resources and awareness. Many cross-border initiatives have been established which treat malaria as a regional problem rather than a country-specific one. Accelerated malaria control efforts have led to a 37% decrease in cases and 60% reduction in deaths. Multi-country efforts have resulted in marked reductions of transmission in the region. Although there have been noteworthy gains in curtailing the disease, new challenges have arisen. The main among these are residual malaria and outdoor biting. One of the main drivers of residual malaria is insecticide resistance. Adding to the burden of residual transmission is the discovery of new vectors that may exist at low densities. To exacerbate these issues is the challenge of malaria imported from high- to low-transmission areas. Nevertheless, compared with the historical picture, we are winning the battle against malaria. Countries in Africa are being certified malaria-free. Partnerships have been developed to take forward the RBM Global Malaria Action Plan. Elimination agendas can only be successful if funding remains sustainable, with greater reliance on domestic funding.

Strengthening Surveillance Systems for Malaria Elimination by Integrating Molecular and Genomic Data.

Unprecedented efforts in malaria control over the last 15 years have led to a substantial decrease in both morbidity and mortality in most endemic settings. However, these progresses have stalled over recent years, and resurgence may cause dramatic impact on both morbidity and mortality. Nevertheless, elimination efforts are currently going on with the objective of reducing malaria morbidity and mortality by 90% and malaria elimination in at least 35 countries by 2030. Strengthening surveillance systems is of paramount importance to reach those targets, and the integration of molecular and genomic techniques into routine surveillance could substantially improve the quality and robustness of data. Techniques such as polymerase chain reaction (PCR) and quantitative PCR (qPCR) are increasingly available in malaria endemic countries, whereas others such as sequencing are already available in a few laboratories. However, sequencing, especially next-generation sequencing (NGS), requires sophisticated infrastructure with adequate computing power and highly trained personnel for data analysis that require substantial investment. Different techniques will be required for different applications, and cost-effective planning must ensure the appropriate use of available resources. The development of national and sub-regional reference laboratories could help in minimizing the resources required in terms of equipment and trained staff. Concerted efforts from different stakeholders at national, sub-regional, and global level are needed to develop the required framework to establish and maintain these reference laboratories.

Fetal Hemoglobin Promotes P. Falciparum Growth in Sickle Cell Disease Erythrocytes

Introduction: We have demonstrated that sickle hemoglobin (HbS) polymerization in low oxygen (O2) is the main driver of sickle cell trait (AS) resistance to P.falciparum malaria. This suggests that homozygous sickle cell disease (SS) individuals should have even greater resistance to malaria. Instead SS individuals infected by P. falciparum often have increased malaria morbidity and mortality compared to individuals with normal hemoglobin (AA) or AS. The reasons for this paradox are poorly understood. We propose that fetal hemoglobin (HbF) inhibits polymerization thereby allowing parasite proliferation. To test this hypothesis the following experiments were performed. Methods: AA and SS erythrocytes were collected within two weeks of the assay date. P. falciparum 3D7 parasites were used for growth assays. Growth assays were performed at 1, 3, 5, 7.5, 10 and 16% O2 using synchronized schizonts obtained by magnet purification via the MACS system. Staging was performed via light microscopy analysis of May-Grünwald-Giemsa-stained cytospins. Parasite Multiplication Rate (PMR) was determined via flow cytometry using parasitemia at 64 and 16 hours post infection (hpi) as previously described. Results: In contrast to AS erythrocytes, SS RBCs contain varying amounts of HbF that differ by cell and by individual. In hypoxic SS RBCs with low (3.8%) HbF, P. falciparum parasites remain immature (early trophozoites) in 1, 3, and 5% O2 (Fig. 1) at 36 hpi, when they should have matured into schizonts. However, in SS RBCs with high (22.6%) HbF, 12, 16 and 27% of parasites matured into schizonts in 1, 3 and 5% O2 respectively compared to 0, 0, and 1% in the SS RBCs with 3.8% HbF. Preliminary data also demonstrate that the parasite multiplication rate (PMR), a surrogate of proliferation, in SS RBCs improves with increasing O2 and HbF. Using SS/Hereditary Persistence of Fetal Hemoglobin RBCs with 42% HbF, proliferation in 5% O2 or higher is exponential with a PMR of 2.6 or greater (Fig. 2). In RBCs isolated from SS patients treated with hydroxyurea with HbF of 26.4 or 21%, PMR is 2 or more in 7.5% O2 or greater. Conclusion: These data demonstrate that HbF promotes P. falciparum growth in SS erythrocytes. In addition, the data initiates a resolution of the malaria paradox. HbS in both hypoxic AS and SS surely inhibits P. falciparum growth due to HbS polymerization at low O2. But high levels of anti-sickling HbF observed in erythrocytes from many individuals with SS reverses this inhibition despite the increased content of HbS in SS individuals. Even small increases in P. falciparum proliferation within the broadly compromised SS host may enhance the malaria associated morbidity and mortality seen in this population. These data further suggest the importance of anti-malarial prophylaxis in patients with SS especially those treated with hydroxyurea or anti-sickling agents. Disclosures No relevant conflicts of interest to declare.

Health education through mass media announcements by loudspeakers about malaria care: prevention and practice among people living in a malaria endemic area of northern Myanmar

BackgroundInterventions to raise community awareness about malaria prevention and treatment have used various approaches with little evidence on their efficacy. This study aimed to determine the effectiveness of loudspeaker announcements regarding malaria care and prevention practices among people living in the malaria endemic villages of Banmauk Township, Sagaing Region, Myanmar.MethodsFour villages among the most malaria-burdened areas were randomly selected: two villages were assigned as the intervention group, and two as the control. Prior to the peak transmission season of malaria in June 2018, a baseline questionnaire was administered to 270 participants from randomly selected households in the control and intervention villages. The loudspeaker announcements broadcasted health messages on malaria care and prevention practices regularly at 7:00 pm every other day. The same questionnaire was administered at 6-month post intervention to both groups. Descriptive statistics, Chi-square, and the t-test were utilized to assess differences between and within groups.ResultsParticipants across the control and intervention groups showed similar socio-economic characteristics; the baseline knowledge, attitude and practice mean scores were not significantly different between the groups. Six months after the intervention, improvements in scores were observed at p-value < 0.001 in both groups, however; the increase was greater among the intervention group. The declining trend of malaria was also noticed during the study period. In addition, more than 75% of people expressed positive opinions of the intervention.ConclusionsThe loudspeaker intervention was found to be feasible and effective, as shown by the significant improvement in scores related to prevention and care-seeking practices for malaria as well as reduced malaria morbidity. Expanding the intervention to a larger population in this endemic region and evaluating its long-term effectiveness are essential in addition to replicating this in other low-resource malaria endemic regions.

Germplasm Release of Four High-artemisinin Clones of Artemisia annua L.

Malaria morbidity is currently on rise and artemisinin combination therapy (ACT) is still the only reliable line of treatment to cure quinine-resistant malaria and the only natural medicine to have a drastic impact on malaria control worldwide. However, commercial cultivars of Artemisia annua (the only commercial source of artemisinin) are only available from a couple of producers in the world and the price is steep for farmers in developing countries afflicted by malaria. Artemisia annua is the only commercial source of artemisinin and produces other compounds that are reported to enhance the antimalarial effect of artemisinin. Although China produces the most artemisinin for the manufacture of ACT, Africa has expanded the cultivation of annual wormwood since 2004. However, high-artemisinin cultivars are not easily available, and it is paramount that countries afflicted by malaria have access to high-artemisinin genotypes of A. annua. During several years, we have selected high-artemisinin genotypes of A. annua, among Brazilian and Chinese genotypes, that can produce from 1.6-2.0% artemisinin on a dry weight basis and high shoot biomass. One of the genotypes (C1) produced 2.16% artemisinin and 3.22 tons of dry leaves·ha-1, based on one plant·m2. Both shoot dry mass/ha and artemisinin can be significantly increased as more plants are used per m2, to a point. Our yield based on 1.0 plant.m2 was twice the average concentration of artemisinin currently reported for commercial cultivars and with estimated potential to produce 70.7 kg artemisinin·ha-1. Our selections were tested under field, greenhouse and tissue culture conditions, and field-selected for high artemisinin. These plants can more than double commercial artemisinin production when used as vegetatively-propagated clones and can reduce both the current market price of artemisinin and of artemisinin-derived ACT. We hereby release our high-artemisinin clones to be used as parents in breeding programs that will result in new lines with higher artemisinin concentration than the ones currently available. The high-artemisinin clones can be an asset in both breeding and research programs destined to produce elite Artemisia germplasm to be distributed among farmers engaged in producing artemisinin as the raw material for antimalaria drugs such as ACT.

KEPADATAN (MAN BITING RATE) NYAMUK ANOPHELES DI DESA RANOKETANG TUA, KECAMATAN AMURANG KABUPATEN MINAHASA SELATAN

Malaria is the most important tropical parasitic disease in the world, and is still a major health problem. South Minahasa Regency was ranked 4th in Malaria Morbidity Rate (API) in 2017. Ranoketang Tua Village was one of the highest cases of malaria, 61 cases, based on data from the 2017 health center. This study aimed to determine the diversity and density (Man Biting Rate) of Mosquitoes Anopheles in Ranoketang Tua Village, Amurang District, South Minahasa Regency. This research is a type of descriptive research. The samples in this study were Anopheles mosquitoes that were caught through the method of insider bait (UOD) and outsider bait (UOL) identified by the species and calculated the Man Bitting Rate (the number of Mosquitoes Biting per person per night). Research Results Found three species of Anopheles namely An. barbirostis, An. tesselatus and An. flavirostris. Density of Anopheles sp mosquitoes in Ranoketang Tua Village, namely An Mosquitoes. barbirostris MBR 49, An Mosquito. flavirostris MBR 3.75 and An Mosquito. tesselatus MBR 0.125. Suggestions to the public to use insecticide-treated mosquito nets, use mosquito coils or reppelant during sleep and wear long-sleeved clothing when doing outdoor activities at night. In order to avoid mosquito bites and reduce the population of Anopheles sp.

Mosquito Exposure and Malaria Morbidity: A Microlevel Analysis of Household Mosquito Populations and Malaria in a Population-Based Longitudinal Cohort in Western Kenya.

Malaria morbidity is highly overdispersed in the population. Fine-scale differences in mosquito exposure may partially explain this heterogeneity in individual malaria outcomes. In 38 households we explored the effect of household-level mosquito exposure and individual insecticide-treated net (ITN) use on relative risk (RR) of confirmed malaria. We conducted monthly active surveillance (n = 254; 2624 person-months) and weekly mosquito collection (2092 household-days of collection), and used molecular techniques to confirm human blood feeding and exposure to infectious mosquitoes. Of 1494 female Anopheles (89.8% Anopheles gambiae sensu lato), 88.3% were fed, 51.9% had a human blood meal, and 9.2% were sporozoite infected. In total, 168 laboratory-confirmed malaria episodes were reported (incidence rate 0.064 episodes per person-month at risk; 95% confidence interval [CI], .055-.074). Malaria risk was directly associated with exposure to sporozoite-infected mosquitoes (RR, 1.24; 95% CI, 1.11-1.38). No direct effect was measured between ITN use and malaria morbidity; however, ITN use did moderate the effect of mosquito exposure on morbidity. Malaria risk increases linearly with vector density and feeding success for persons with low ITN use. In contrast, malaria risk among high ITN users is consistently low and insensitive to variation in mosquito exposure.

Epidemiological Trends of Malaria in Eastern Shan State, Myanmar 2000-2016

Malaria is a priority communicable disease in Eastern Shan State (ESS) of Myanmar. This study aimed to describe the malaria situation, epidemiology and treatment services in ESS during 2000-2016. Data from township malaria monthly reports in ESS during 2000-2016 were analyzed by time, place, person, species and treatment services. Malaria morbidity, mortality and case-fatality rate decreased from 25.0 to 3.7 per 1,000 population, 15.0 to 0.2 per 100,000 population and 4.6% to 1.3%, respectively, during 2000-2016. The male to female ratio was 3:2 and those over 15 years old constituted 60% of all cases. The number of cases declined by 88% and 99% among those younger than 5 years of age and pregnant women, respectively. During 2011-2016, the case detection rate increased from 2% to 12%, and 94% of blood examinations used a rapid diagnostic test. Plasmodium vivax (63%) was the most prevalent parasite species, followed by Plasmodium falciparum (33%) while mixed parasites accounted for 4% of all infections. Non-government-controlled areas contributed more than 80% of cases between 2013 and 2016. Remarkable reductions in malaria morbidity and mortality in ESS followed improvements in early detection, appropriate treatment and effective vector control. However, the overwhelming contribution on caseload in non-government-controlled areas remain a challenge for the elimination of malaria in Myanmar.