Treatment Of Malaria Infections Research Articles

Evaluation of Andrographis paniculata-supplemented Diet on the reproductive indices of Plasmodium berghei-infected mice

Ethnopharmacological relevanceThe King of Bitters (Andrographis paniculata) is a plant used to cure a wide range of infectious diseases which includes malaria, fever and others. However, there is a paucity of scientific evidence of its effect on male reproductive indices during malaria treatment. Aim of the studyThe aim of this study is to evaluate the effect of supplemented diet on antiplasmodial, hematological and male reproductive indices in mice infected with Plasmodium berghei. Materials and methodsAqueous extract of A. paniculata (King of Bitters, KGB) was prepared and the total phenol and flavonoid contents were determined. Forty-two mice, weighing 20–25 g, were distributed into 7 groups consisting of 6 mice each. The mice were innoculated with strain NK65 Plasmodium berghei (Chloroquine, CQ sensitive) and the parasitemia suppression was assessed. The mice were fed with the dietary supplementation of KGB at varying inclusions (2.5%, 5%, 7.5%, and 10%) and administered 10 mg/kg CQ (which served as the positive control) for 5 consecutive days after infection was established. The reactive malondialdeahyde (MDA), antioxidant [superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH)] and the hematological (hemoglobin, packed cell volume and red blood cell) parameters in the infected mice were determined. The reproductive indices (serum testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), sperm count, sperm motility, and sperm viability) and testis histopathology were also assessed. ResultThe result revealed that KGB had a total phenol content of 32.55 mgGAE/g and total flavonoid content of 19.71 mgQUE/g. The infected mice treated with the dietary supplementation of KGB showed significantly decreased (p < 0.05) parasitaemia and MDA levels. Furthermore, the 7.5% dietary inclusion showed significant improvement in the antioxidant, hematological and reproductive indices as well as the restoration of testis morphology as seen in the histopathology plate of the infected mice treated with KGB. Hence, this study suggests that the KGB- supplemented diet (7.5%) may be a potential alternative and complementary therapy in the treatment of malaria infection and reproductive disorders.

Analysis of complementarities between nanomedicine and phytodrugs for the treatment of malarial infection.

The use of nanocarriers in medicine, so-called nanomedicine, is one of the most innovative strategies for targeting drugs at the action site and increasing their activity index and effectiveness. Phytomedicine is the oldest traditional method used to treat human diseases and solve health problems. The recent literature on the treatment of malaria infections using nanodelivery systems and phytodrugs or supplements has been analyzed. For the first time, in the present review, a careful look at the considerable potential of nanomedicine in promoting phytotherapeutic efficacy was done, and its key role in addressing a translation through a significant reduction of the current burden of malaria in many parts of the world has been underlined.

SD-Bioline malaria rapid diagnostic test performance and time to become negative after treatment of malaria infection in Southwest Nigerian Children.

Given the challenges of microscopy, we compared its performance with SD-Bioline malaria rapid diagnostic test (MRDT) and polymerase chain reaction (PCR) and evaluated the time it took for positive results to become negative after treatment of children with acute uncomplicated malaria. We present the report of 485 participants with complete MRDT, microscopy, and PCR data out of 511 febrile children aged 3-59 months who participated in a cohort study over a 12-month period in rural and urban areas of Ibadan, Nigeria. MRDT-positive children received antimalaria and tested at every visit over 28 days. Speciation was also carried out by PCR. With microscopy as the gold standard, SD-Bioline™ had 95.2% sensitivity, 66.4% specificity, 67.5% positive predictive value (PPV), and 94.9 negative predictive value (NPV), while with PCR the findings were 84.3% sensitivity, 66.5% specificity, 72.7% PPV, and 80.1% NPV. PCR speciation of malaria parasites revealed 91.6% Plasmodium falciparum, 18.9% Plasmodium malariae, and 4.4% Plasmodium ovale. Among the 47 children with P. malariae infections, 66.0% were coinfected with P. falciparum, while 54.6% cases of P. ovale occurred as coinfections with P. falciparum. The median time to a negative MRDT was 23.2 days, while the median time to a negative malaria microscopy was 3.8 days. The two survival curves were significantly different. The SD-BiolineTM MRDT performed well, with remarkable persistence of rapid test-positive for an average of 23 days post treatment. The prevalence of P. malaria is somewhat greater than expected.

Prolonged fever and exaggerated hypercoagulopathy in malaria vivax relapse and COVID-19 co-infection: a case report

BackgroundCoronavirus disease 2019 (COVID-19) often causes atypical clinical manifestations similar to other infectious diseases. In malaria-endemic areas, the pandemic situation will very likely result in co-infection of COVID-19 and malaria, although reports to date are still few. Meanwhile, this disease will be challenging to diagnose in areas with low malaria prevalence because the symptoms closely resemble COVID-19.Case presentationA 23-year-old male patient presented to the hospital with fever, anosmia, headache, and nausea 1 week before. He was diagnosed with COVID-19 and treated for approximately 10 days, then discharged to continue self-quarantine at home. 2 weeks later, he returned to the hospital with a fever raised intermittently every 2 days and marked by a chilling-fever-sweating cycle. A laboratory test for malaria and a nasopharyngeal swab for SARS CoV-2 PCR were conducted, confirming both diagnoses. The laboratory examination showed markedly elevated D-dimer. He was treated with dihydroartemisinin-piperaquine (DHP) 4 tablets per day for 3 days and primaquine 2 tablets per day for 14 days according to Indonesian National Anti-malarial Treatment Guidelines. After 6 days of treatment, the patient had no complaints, and the results of laboratory tests had improved. This report describes the key points in considering the differential diagnosis and prompt treatment of malaria infection during the pandemic of COVID-19 in an endemic country to prevent the worse clinical outcomes. COVID-19 and malaria may also cause a hypercoagulable state, so a co-infection of those diseases may impact the prognosis of the disease.ConclusionThis case report shows that considering the possibility of a co-infection in a COVID-19 patient who presents with fever can prevent delayed treatment that can worsen the disease outcome. Paying more attention to a history of travel to malaria-endemic areas, a history of previous malaria infection, and exploring anamnesis regarding the fever patterns in patients are important points in making a differential diagnosis of malaria infection during the COVID-19 pandemic.

In Vitro Assessment of anti plasmodial activity of Albizia chevalieri extracts against Plasmodium falciparum

Medicinal plants play a key role in malaria control in Africa, especially in remote areas where health facilities are limited. This study was carried out with the aim to investigate the anti plasmodial activity of Albizia chevalieri against Plasmodium falciparum. The three aerial parts of Albizia chevalieri were extracted using methanol via maceration process. Anti plasmodial assay was carried out in duplicate in the 96-well microtitre plate. The anti Plasmodial activity of A. chevalieri methanolic extracts observed in this study may be attributed to the presence of some bioactive compounds. The effect of A. chevalieri methanolic extracts and reference drugs showed a decrease in percentage parasitaemia with increasing concentration. With regard to concentrations administered, a dose-dependent antimalarial activity was clearly shown for crude extract, isolates and the reference drugs. Artemether, the root isolate and leaf isolate exhibited a remarkable antiplasmodial activity. Root, leaf extracts and the pure isolates when compared with the standard drug that has the highest percentage inhibition shows no significance difference at (P&gt;0.05). However, when compared with the other drugs such as Chloroquine, Quinine shows a significance percentage inhibition difference at (P&gt;0.05). Considering the inhibitory effect of A. chevalieri methanol extracts on the growth of P. falciparum as reported in this study, it is concluded that the anti plasmodial activity of the plant on P. falciparum suggests its potency in the treatment of malaria infection. Further study on this plant is on-going to isolate, identify and characterize the bioactive compounds from this plant responsible for this bioactivity, and also to carry- out the drug synthesis.

Identification of 3,4-Dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine Derivatives as Novel Selective Inhibitors of Plasmodium falciparum Dihydroorotate Dehydrogenase.

Plasmodium falciparum’s resistance to available antimalarial drugs highlights the need for the development of novel drugs. Pyrimidine de novo biosynthesis is a validated drug target for the prevention and treatment of malaria infection. P. falciparum dihydroorotate dehydrogenase (PfDHODH) catalyzes the oxidation of dihydroorotate to orotate and utilize ubiquinone as an electron acceptor in the fourth step of pyrimidine de novo biosynthesis. PfDHODH is targeted by the inhibitor DSM265, which binds to a hydrophobic pocket located at the N-terminus where ubiquinone binds, which is known to be structurally divergent from the mammalian orthologue. In this study, we screened 40,400 compounds from the Kyoto University chemical library against recombinant PfDHODH. These studies led to the identification of 3,4-dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine and its derivatives as a new class of PfDHODH inhibitor. Moreover, the hit compounds identified in this study are selective for PfDHODH without inhibition of the human enzymes. Finally, this new scaffold of PfDHODH inhibitors showed growth inhibition activity against P. falciparum 3D7 with low toxicity to three human cell lines, providing a new starting point for antimalarial drug development.

Antiplasmodial Activity of compounds isolated from Albizia chevalieri against Plasmodium falciparum

Therapeutic plants play a key position in malaria control in Africa, especially in public areas where health facilities are insufficient. In order to charge their much-admired potentials, this study is aimed to determine the in-vitro antiplasmodial activity of the compound isolated from Albizia chevalieri against plasmodium falciparum. The three Arial parts of the plant was extracted with methanol via maceration method. The most active extracts were isolated for bioactive compounds using column chromatographic technique while Antiplasmodial assay for the isolated compounds was also carried out in duplicate in the 96-well microtitre plate; Exactly 100µl of culture medium was dispensed into all the wells in a 96-well microtitre plate leaving only the “A” series. Then, 100µl of the working solutions (isolated compounds and standard drugs) were pipette in to the well “A” series. Serial dilutions were then prepared by pipetting 50µl of the solutions from the “A” series well down the rows up to the” G”series wells, leaving series 12 from wells, down the rows to “H” only with the culture medium, serving as control. The extra 50 µl of test substance dilution series were discarded. Exactly 25 µl of the infected red cells was separated and were added into all the wells in the test plates using the multi-channel micropipette and were mixed by swirling with the tips to ensure homogeneity. The microtitre plates were incubated in CO2 condition at 370C in candle jar for 30 hours. The effect of A.chevalieri compounds isolates and reference drug showed a decrease in percentage parasitaemia with increasing concentration. With regard to concentrations administered, a dose-dependent antimalarial activity was clearly shown for isolates and the reference drugs. artemether, root isolate and leaf isolate exhibited a remarkable antiplasmodial activity, the pure isolates when compared with the standard drug that has the highest percentage inhibition shows no significance difference at (P>0.05), but when compared with the other drugs such as Chloroquine, Quinine shows a significance difference at (P>0.05). It is concluded that the antiplasmodial activity of the plant on P. falciparum suggests its effectiveness in the treatment of malaria infection. The work also confirms the likelihood of conducting in-vivo antiplasmodial activity of the isolated compounds from Albizia chevalier.

Pattern of anti-malarial drugs and artemether combination therapy adherence in an institution based medical centre, Nigeria

The change in policy guidelines for treating uncomplicated malaria became necessary because the therapeutic efficacy of chloroquine and SP had deteriorated. Hence compliance is a necessity to enable effective check on malaria. This work was carried out to evaluate antimalaria drug prescription and to update its usage in line with WHO guideline on Artemeter Combination therapy in a university based medical center. We utilized descriptive, cross-sectional, retrospective study of antimalaria prescriptions purposely carried out among male and female outpatients with mean age of 22.4±2.8 at a University health facility. This comprised all outpatients prescriptions that contained at least one antimalarial drug filed from October 2018 to September 2019. Systematic sampling was used to select the prescriptions. Based on the total number of 1250 prescriptions containing at least one antimalarial drug, a sampling interval of 5 was calculated and simple balloting was used for the first pick. A total number of two hundred and fifty (250) prescriptions containing at least one antimalarial drug were selected for the study. Out of 250 antimalaria prescriptions, usage of ACT class of Artemeter lumefantrine, Artemeter Amodiaquine and Artemeter Piparaqiune were recorded at 45.6%, 10.4% and 9.6% respectively. Triple combination Artemeter lumefantrine and Sulphadoxine-Pyrimethamine was recorded at 20.4% while Sulphadoxine-Pyrimethamine was recorded at 4%. Combination of antimalarial drugs with antibiotics was recorded at 31.2%. This study showed compliance with National Antimalarial Treatment Guideline for the treatment of malaria infection as it regards the use of artemisinin-based combination therapy. The frequency usage of artemeter lumefantrine was proceeding among other ACTs. The frequency in co-prescription of antibiotics with anti-malaria should be guarded to comply with WHO recommendation.

Exploration and identification of novel inhibitors against Knowpain-4 of P. knowlesi using a combinatorial 3D pharmacophore modeling approach

Papain-like cysteine protease of P. knowlesi is a significant target for the treatment of malaria infection. P. knowlesi poses a new threat to malaria eradication programs as it starts infecting humans. We have targeted P. knowlesi Knowpain-4 protein for inhibitor designing based on the molecular modeling simulations and structure-based pharmacophore modeling. In-depth sequence analysis reveals its crucial role in host hemoglobin degradation. Dihedral angles and QMEAN score analysis successfully validate the modeled structure of Knowpain4. The docking simulation leads to the prediction of E64 poses at the binding site of Knowpain4 protein. The ligand–receptor interaction information is used for generating five different pharmacophore models taking a diverse set of parameters. A combined 3D features-based, a pharmacophore model is assembled to screen in-house database. The presence of E64, along with 2,128 compounds in the output cross-confirms our screening model. Later on, top 22 screened compounds with higher relative pharmacophore score to E64 is selected for interaction study. The docking simulation experiments result in the identification of 6 compounds that occupies the functional, active site of Knowpain4 protein with high binding affinity. Further, pharmacokinetic studies showed that the identified compounds are potential bioactive molecules with unique scaffolds, and may have the potential to block the expression of Knowpain4 protease.

Effectiveness of the innovative 1,7-malaria reactive community-based testing and response (1, 7-mRCTR) approach on malaria burden reduction in Southeastern Tanzania

BackgroundIn 2015, a China-UK-Tanzania tripartite pilot project was implemented in southeastern Tanzania to explore a new model for reducing malaria burden and possibly scaling-out the approach into other malaria-endemic countries. The 1,7-malaria Reactive Community-based Testing and Response (1,7-mRCTR) which is a locally-tailored approach for reporting febrile malaria cases in endemic villages was developed to stop transmission and Plasmodium life-cycle. The (1,7-mRCTR) utilizes existing health facility data and locally trained community health workers to conduct community-level testing and treatment.MethodsThe pilot project was implemented from September 2015 to June 2018 in Rufiji District, southern Tanzania. The study took place in four wards, two with low incidence and two with a higher incidence. One ward of each type was selected for each of the control and intervention arms. The control wards implemented the existing Ministry of Health programmes. The 1,7-mRCTR activities implemented in the intervention arm included community testing and treatment of malaria infection. Malaria case-to-suspect ratios at health facilities (HF) were aggregated by villages, weekly to identify the village with the highest ratio. Community-based mobile test stations (cMTS) were used for conducting mass testing and treatment. Baseline (pre) and endline (post) household surveys were done in the control and intervention wards to assess the change in malaria prevalence measured by the interaction term of ‘time’ (post vs pre) and arm in a logistic model. A secondary analysis also studied the malaria incidence reported at the HFs during the intervention.ResultsOverall the 85 rounds of 1,7-mRCTR conducted in the intervention wards significantly reduced the odds of malaria infection by 66% (adjusted OR 0.34, 95% CI 0.26,0.44, p < 0001) beyond the effect of the standard programmes. Malaria prevalence in the intervention wards declined by 81% (from 26% (95% CI 23.7, 7.8), at baseline to 4.9% (95% CI 4.0, 5.9) at endline). In villages receiving the 1,7-mRCTR, the short-term case ratio decreased by over 15.7% (95% CI − 33, 6) compared to baseline.ConclusionThe 1,7-mRCTR approach significantly reduced the malaria burden in the areas of high transmission in rural southern Tanzania. This locally tailored approach could accelerate malaria control and elimination efforts. The results provide the impetus for further evaluation of the effectiveness and scaling up of this approach in other high malaria burden countries in Africa, including Tanzania.

Impact of Intermittent Mass Testing and Treatment on Incidence of Malaria Infection in a High Transmission Area of Western Kenya.

Progress with malaria control in western Kenya has stagnated since 2007. Additional interventions to reduce the high burden of malaria in this region are urgently needed. We conducted a two-arm, community-based, cluster-randomized, controlled trial of active case detection and treatment of malaria infections in all residents mass testing and treatment (MTaT) of 10 village clusters (intervention clusters) for two consecutive years to measure differences in the incidence of clinical malaria disease and malaria infections compared with 20 control clusters where MTaT was not implemented. All residents of intervention clusters, irrespective of history of fever or other malaria-related symptoms, were tested three times per year before the peak malaria season using malaria rapid diagnostic tests. All positive cases were treated with dihydroartemisinin-piperaquine. The incidence of clinical malaria was measured through passive surveillance, whereas the cumulative incidence of malaria infection was measured using active surveillance in a cohort comprising randomly selected residents. The incidence of clinical malaria was 0.19 cases/person-year (p-y, 95% CI: 0.13-0.28) in the intervention arm and 0.24 cases/p-y (95% CI: 0.15-0.39) in the control arm (incidence rate ratio [IRR] 0.79, 95% CI: 0.61-1.02). The cumulative incidence of malaria infections was similar between the intervention (2.08 infections/p-y, 95% CI: 1.93-2.26) and control arms (2.19 infections/p-y, 95% CI: 2.02-2.37) with a crude IRR of 0.95 (95% CI: 0.87-1.04). Six rounds of MTaT over 2 years did not have a significant impact on the incidence of clinical malaria or the cumulative incidence of malaria infection in this area of high malaria transmission.

Effectiveness of the Innovative 1,7-Malaria Reactive Community-Based Testing and Response Approach (1, 7-mRCT) on Malaria Burden Reduction in Southeastern Tanzania

Background: In 2015, a China-UK-Tanzania tripartite pilot project was implemented in south-eastern Tanzania to explore a new model to reduce the malaria burden with the aim of eventually scaling-up the approach in Africa. Chinese and Tanzanian teams have developed a locally-tailored malaria control approach screening for febrile cases in endemic villages on Day 1 followed by focal treatment of holoendemic villages within 7 days to stop transmission at the same phase of the plasmodium life-cycle. This 1,7-Reactive Community-based Testing and Response (1,7-mRCT) model can utilize existing health facility data and locally trained community-based health workers to conduct community-level testing and treatment. Methods: Matched malaria incidence pairs of control and intervention wards were chosen. The latter arm was selected for the 1,7-mRCT approach, while the control wards relied on long-lasting insecticide-treated bednets only. The 1,7-mRCT activities included community testing and treatment of malaria infection. Case-to-suspect ratios of malaria cases were aggregated at the village level weekly to identify the village with the highest ratio. Community-based mobile test stations (cMTS) were used for mass testing and treatment. The pilot project was implemented from September 2015 to June 2018 with 85 rounds of 1,7-mRCT implemented in the intervention wards. Comparing the two arms of approach we look for any change in malaria prevalence from the baseline to the endline survey. Besides we also studied the malaria incidence reported at the health facilities after interventions in the treated villages. Findings: Compared to the control wards, the 1,7-mRCT model significantly reduced the malaria infections by 66% (adjusted OR 0.34, 95%CI 0.26-0.44, p<0001) over and above the benefit of the bednets. Malaria prevalence in the intervention wards declined by 81% (from 26% (95% CI, 23.7-27.8), at the baseline to 4.9% (95% CI, 4.0-5.9) at the endline survey). In the villages receiving the 1,7-mRCT, the case ratio decreased by over 15.7% (95%CI, -33, 6) compared to pretreatment levels. Interpretation: The 1,7-mRCT approach resulted in a significant reduction of the malaria burden in the areas of moderate and high transmission in southern Tanzania. Thus, this locally tailored approach could accelerate malaria control and elimination efforts in Africa. The results provide the impetus for further evaluation of its effectiveness and scaling up of local adaptations to the 1-7mRCT approach in other high malaria burden countries including Tanzania across the African continent. Funding Statement: China-UK Global Health Support Programme (GHSP-CS-OP4-D02) funded by UK DFID. Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: The Medical Research Coordination Committee of the National Institute of Medical Research granted the permit to conduct the ethics approval for the study (NIMR/HQ/R.8a/Vol.IX/2005). Institution ethical approval was also obtained from the Ifakara Health Institute Institutional Review Board (IHI/IRB/No: 18-2015) and the Chinese Centre for Disease Control. Informed consent was obtained.

A mevalonate bypass system facilitates elucidation of plastid biology in malaria parasites.

Malaria parasites rely on a plastid organelle for survival during the blood stages of infection. However, the entire organelle is dispensable as long as the isoprenoid precursor, isopentenyl pyrophosphate (IPP), is supplemented in the culture medium. We engineered parasites to produce isoprenoid precursors from a mevalonate-dependent pathway, creating a parasite line that replicates normally after the loss of the apicoplast organelle. We show that carbon-labeled mevalonate is specifically incorporated into isoprenoid products, opening new avenues for researching this essential class of metabolites in malaria parasites. We also show that essential apicoplast proteins, such as the enzyme target of the drug fosmidomycin, can be deleted in this mevalonate bypass parasite line, providing a new method to determine the roles of other important apicoplast-resident proteins. Several antibacterial drugs kill malaria parasites by targeting basic processes, such as transcription, in the organelle. We used metabolomic and transcriptomic methods to characterize parasite metabolism after azithromycin treatment triggered loss of the apicoplast and found that parasite metabolism and the production of apicoplast proteins is largely unaltered. These results provide insight into the effects of apicoplast-disrupting drugs, several of which have been used to treat malaria infections in humans. Overall, the mevalonate bypass system provides a way to probe essential aspects of apicoplast biology and study the effects of drugs that target apicoplast processes.

An ImmunoPEGliposome for Targeted Antimalarial Combination Therapy at the Nanoscale.

Combination therapies, where two drugs acting through different mechanisms are administered simultaneously, are one of the most efficient approaches currently used to treat malaria infections. However, the different pharmacokinetic profiles often exhibited by the combined drugs tend to decrease treatment efficacy as the compounds are usually eliminated from the circulation at different rates. To circumvent this obstacle, we have engineered an immunoliposomal nanovector encapsulating hydrophilic and lipophilic compounds in its lumen and lipid bilayer, respectively. The antimalarial domiphen bromide has been encapsulated in the liposome membrane with good efficiency, although its high IC50 of ca. 1 µM for living parasites complicates its use as immunoliposomal therapy due to erythrocyte agglutination. The conjugation of antibodies against glycophorin A targeted the nanocarriers to Plasmodium-infected red blood cells and to gametocytes, the sole malaria parasite stage responsible for the transmission from the human to the mosquito vector. The antimalarials pyronaridine and atovaquone, which block the development of gametocytes, have been co-encapsulated in glycophorin A-targeted immunoliposomes. The co-immunoliposomized drugs have activities significantly higher than their free forms when tested in in vitro Plasmodium falciparum cultures: Pyronaridine and atovaquone concentrations that, when encapsulated in immunoliposomes, resulted in a 50% inhibition of parasite growth had no effect on the viability of the pathogen when used as free drugs.

Intermittent screening and treatment or intermittent preventive treatment compared to current policy of single screening and treatment for the prevention of malaria in pregnancy in Eastern Indonesia: acceptability among health providers and pregnant women

BackgroundThe control of malaria in pregnancy in much of Asia relies on screening asymptomatic women for malaria infection, followed by passive case detection and prevention with insecticide-treated nets. In 2012, Indonesia introduced screening for malaria by microscopy or rapid diagnostic tests (RDTs) at pregnant women’s first antenatal care (ANC) visit to detect and treat malaria infections regardless of the presence of symptoms. Acceptability among health providers and pregnant women of the current ‘single screen and treat’ (SSTp) strategy compared to two alternative strategies that were intermittent preventive treatment (IPTp) and intermittent screening and treatment (ISTp) was assessed in the context of a clinical trial in two malaria endemic provinces of Eastern Indonesia.MethodsQualitative data were collected through in-depth interviews with 121 health providers working in provision of antenatal care, heads of health facilities and District Health Office staff. Trial staff were also interviewed. Focus group discussions were conducted with 16 groups of pregnant women (N = 106) to discuss their experiences of each intervention in the trial.ResultsHealth providers and pregnant women were receptive to screening for malaria at every ANC visit due to the increased opportunity to detect and treat asymptomatic infections. A primary concern for providers was the accuracy and availability of RDTs used for screening in the SSTp and ISTp arms, which they considered less accurate than microscopy. Providers had reservations about giving anti-malarials presumptively as IPTp, due to concerns of causing potential harm to mother and baby and as a possible driver of drug resistance. Pregnant women were accepting of all three interventions. Women in the IPTp arm were happy to take anti-malarials presumptively to protect themselves and their babies against malaria.ConclusionsThe findings indicate that, within a trial context, malaria screening of pregnant women at every ANC visit ISTp was an acceptable strategy among both health providers and pregnant women owing to an existing culture of screening and treatment. The adoption of IPTp however would require a considerable shift in health provider attitudes and a clear communication strategy. By contrast, pregnant women welcomed the opportunity to prevent malaria infections during pregnancy.

Piloting a programme tool to evaluate malaria case investigation and reactive case detection activities: results from 3 settings in the Asia Pacific

BackgroundCase investigation and reactive case detection (RACD) activities are widely-used in low transmission settings to determine the suspected origin of infection and identify and treat malaria infections nearby to the index patient household. Case investigation and RACD activities are time and resource intensive, include methodologies that vary across eliminating settings, and have no standardized metrics or tools available to monitor and evaluate them.MethodsIn response to this gap, a simple programme tool was developed for monitoring and evaluating (M&E) RACD activities and piloted by national malaria programmes. During the development phase, four modules of the RACD M&E tool were created to assess and evaluate key case investigation and RACD activities and costs. A pilot phase was then carried out by programme implementers between 2013 and 2015, during which malaria surveillance teams in three different settings (China, Indonesia, Thailand) piloted the tool over a period of 3 months each. This study describes summary results of the pilots and feasibility and impact of the tool on programmes.ResultsAll three study areas implemented the RACD M&E tool modules, and pilot users reported the tool and evaluation process were helpful to identify gaps in RACD programme activities. In the 45 health facilities evaluated, 71.8% (97/135; min 35.3–max 100.0%) of the proper notification and reporting forms and 20.0% (27/135; min 0.0–max 100.0%) of standard operating procedures (SOPs) were available to support malaria elimination activities. The tool highlighted gaps in reporting key data indicators on the completeness for malaria case reporting (98.8%; min 93.3–max 100.0%), case investigations (65.6%; min 61.8–max 78.4%) and RACD activities (70.0%; min 64.7–max 100.0%). Evaluation of the SOPs showed that knowledge and practices of malaria personnel varied within and between study areas. Average monthly costs for conducting case investigation and RACD activities showed variation between study areas (min USD $844.80–max USD $2038.00) for the malaria personnel, commodities, services and other costs required to carry out the activities.ConclusionThe RACD M&E tool was implemented in the three pilot areas, identifying key gaps that led to impacts on programme decision making. Study findings support the need for routine M&E of malaria case reporting, case investigation and RACD activities. Scale-up of the RACD M&E tool in malaria-eliminating settings will contribute to improved programme performance to the high level that is required to reach elimination.

Artemisinin and malaria: Current understandings of drug activation, action, and resistance

Malaria is a disease that can be cured with antimalarial drugs if treated early and appropriately. However, parasites resistant to a new drug generally emerge within a few years after large-scale applications. Artemisinin (ART or Qinghaosu) combination therapies (ACTs) have become the major treatments for malaria after the emergence of parasites resistant to almost all classes of antimalarial drugs. Parasites with delayed parasite clearance (DPC) after ART or ACT therapies have also been reported in Southeast Asia, raising concerns of total failure of ART and its derivatives. Many classes of antimalarial drugs have been introduced to successfully treat malaria infections, including chloroquine, piperaquine, primaquine, mefloquine (MQ), pyrimethamine, sulfadoxine, ART and derivatives, etc. Regrettably, many of these drugs have been abandoned by many countries in malaria endemic regions due to the emergence of drug resistant parasites. According to World Health Organization, parasite responses to a drug can be classified into four categories (S, RI, RII, and RIII): Sensitivity (S) to a drug is defined as clearance of asexual parasitemia within seven days of the first day of treatment without recrudescence; Resistance RI is defined as clearance of asexual parasitemia as in sensitive parasites, followed by recrudescence; RII resistance is indicated by marked reduction of asexual parasitemia, but no clearance; and RIII resistance shows no marked reduction of asexual parasitemia. Currently, RII and RIII resistance to chloroquine, pyrimethamine, and other drugs have been widely reported; but residence to ART remains largely at R1 level. ART resistance was initially defined as parasites with half parasite clearance time (PC1/2)>5 h under a standard ART treatment regimen (three-day artesunate treatment at 2–4 mg kg - 1 d - 1). A second measurement is in vitro ring survival assay (RSA) that was developed based on the observation that the ring stages of some parasite strains could survive a short period of ART treatment. Another indicator of increasing ART tolerance is the elevated rate of recrudescence after ART or ACT treatments. The generation of highly reactive radicals via endoperoxide cleavage is critical for ART activation. Both free ferrous iron and heme have been proposed to be the predominant iron sources for ART activation. The heme required for ART activation can be derived from the parasite’s heme biosynthesis pathway at the early ring stage and/or from hemoglobin digestion at later stages. A large number of parasite molecules have been found to bind or interact with ART, most notably the Plasmodium falciparum ATPase 6 (PfATP6 or SERCA), phosphatidylinositol-3-kinase (PfPI3K), chloroquine resistance transporter (PfCRT), and multiple drug resistance 1 (PfMDR1). Recently, a gene encoding a parasite Kelch protein (“K13”) with a six-blade propeller domain was identified as a potential molecular marker of ART resistance in vivo (DPC>5 h) and in vitro (RSA). Various antimalarial drugs such as meflouine and piperaquine have been used as partner drugs in ACTs. However, parasites resistant to these partner drugs have also been reported, which may explain the reported slow parasite clearance after ACT treatment. The success of ACTs in treating malaria infections has generated optimism and proposals for malaria eradication by mass drug administration (MDA), and successes have been achieved from several studies. However, the impact of MDA on malaria transmission in the long term, especially in low- and moderate-transmission settings, and the potential consequences of developing drug resistance, requires careful evaluation. There are a large number of studies and publications on these related subjects, and it is impossible to include or cite all the publications in this review. Additionally, some of the issues discussed here are still being debated, requiring further investigation.

Antiplasmodial activity and cytotoxicity of ethanol extract of Zea mays root.

Zea mays root decoction that has been traditionally used for the treatment of malaria by various tribes in Nigeria, was evaluated for antimalarial potential against malaria parasites using in vivo and in vitro models. The root extract of Zea mays was investigated for antimalarial activity against Plasmodium berghei in mice using rodent malaria models; suppressive, prophylactic and curative tests and in vitro antiplasmodial activity against chloroquine-sensitive (Pf 3D7) and resistant (Pf INDO) strains of Plasmodium falciparum using SYBR green assay method. Median lethal dose and cytotoxic activity against HeLa and HEKS cells were assessed and phytochemical screening was also carried out using standard procedures. The LD50 value of root extract was found to be 474.34 mg/kg. The crude extract (45-135 mg/kg, p.o) showed significant (p<0.05-0.001) antimalarial activity against P. berghei infection in suppressive, prophylactic and curative tests with a prolonged survival time. The crude extract also showed moderate activity against both chloroquine-sensitive (Pf 3D7) and resistant (Pf INDO) strains of P. falciparum with an IC50 value of 71.62±3.38 μg/ml (for Pf 3D7) and 63.76±4.12 μg/ml (for Pf INDO). The crude extract was not cytotoxic to the two cell lines tested with TC50 of >100 μg/ml against both HeLa and HEKS cell lines. These results suggest that the root extract of Zea mays possesses antimalarial activity against both chloroquine-sensitive and resistant malaria and these data justify its use in ethnomedicine to treat malaria infections.

Antimalarial and antiplasmodial activity of husk extract and fractions of Zea mays

Context: Zea mays L. (Poacae) husk decoctions are traditionally used in the treatment of malaria by various tribes in Nigeria.Objective: To assess the antimalarial and antiplasmodial potentials of the husk extract and fractions on malaria parasites using in vivo and in vitro models.Materials and methods: The ethanol husk extract and fractions (187–748 mg/kg, p.o.) of Zea mays were investigated for antimalarial activity against Plasmodium berghei using rodent (mice) malaria models and in vitro activity against chloroquine sensitive (Pf 3D7) and resistant (Pf INDO) strains of Plasmodium falciparum using the SRBR green assay method. Median lethal dose and cytotoxic activities against HeLa and HEKS cells were also carried out. The GCMS analysis of the most active fraction was carried out.Results: The husk extract (187–748 mg/kg, p.o.) with LD50 of 1874.83 mg/kg was found to exert significant (p < 0.05–0.001) antimalarial activity against P. berghei infection in suppressive, prophylactive and curative tests. The crude extract and fractions also exerted prominent activity against both chloroquine sensitive (Pf 3D7) and resistant (Pf INDO) strains of P. falciparum with the ethyl acetate fraction exerting the highest activity with IC50 values of 9.31 ± 0.46 μg/mL (Pf 3D7) and 3.69 ± 0.66 μg/mL (Pf INDO). The crude extract and fractions were not cytotoxic to the two cell lines tested with IC50 values of >100 μg/mL against both HeLa and HEKS cell lines.Discussion and conclusion: These results suggest that the husk extract/fractions of Zea mays possesses antimalarial and antiplasmodial activities and these justify its use in ethnomedicine to treat malaria infections.

Antiplasmodial, antioxidant and immunomodulatory activities of ethanol extract of Vernonia amygdalina del. Leaf in Swiss mice.

Vernonia amygdalina (V. amygdalina) leaf is locally employed in the Southern region of Nigeria in the treatment of malaria infection. This study evaluated the in vivo antiplasmodial, antioxidant and immunomodulatory effect of ethanol extract of V. amygdalina leaf. The active principles of the dried leaf were extracted with ethanol. For quality validation, chemical finger-print of the extract was performed through high performance thin layer chromatography (HPTLC). The extract was assessed for antiplasmodial activity by the standard four-day suppressive test on Plasmodium berghei (ANKA) infected male Swiss mice (six weeks old) placed into five groups of six animals each. The absorption spectra from the HPTLC revealed several peaks suggesting presence of some bioactive compounds. Results from the in vivo study showed that the ethanol extract of the plant leaf was significantly active against P. berghei in a dose-dependent manner with the minimum and maximum activity observed in the mice treated orally with 100mg/kg (% inhibition of 23.7%) and 1000 mg/kg (% inhibition of 82.3 %) of the extract, respectively, on day four of the study. There was also a dose-dependent decrease (p<0.05) in some oxidative stress indices including nitric oxide and lipid peroxidation levels in the extract treated groups as against the non-treated infected group which had high levels of these parameters. The pro-inflammatory cytokines (TNF-α and IFN-ɣ) levels were also considerably low in the extract treated groups relative to the non-treated infected group. The results suggest that ethanol extract of V. amygdalina leaf was active, with some immunomodulatory effect, against P . berghei infection.