Plasmodium falciparum Recrudescence Two Years after Treatment of an Uncomplicated Infection without Return to an Area Where Malaria Is Endemic.

We report evidence, confirmed by the lack of travel activity outside of France and genetic diversity analysis using polymorphic microsatellite markers, that Plasmodium falciparum malaria infection effectively treated with an artemisinin-based combination can remain dormant and relapse during pregnancy at least 2 years after treatment.

Introducing the concept of a new pre-referral treatment for severely ill febrile children at community level: a sociological approach in Guinea-Bissau.

BACKGROUND: Innovative strategies are needed to tackle childhood mortality in the rural tropics. Artesunate suppositories were developed to bring emergency treatment closer to severely ill children with malaria in rural areas where injectable treatment is not possible for several hours. Adding an antibacterial rectal drug would extend this strategy to treat non-malarial febrile illness as well. The objective of these studies was to assess acceptability of such a new pre-referral strategy by healthcare providers and likely uptake by the population. METHODS: Two qualitative studies were conducted between May and July 2009. Study 1 investigated the acceptability of introducing a combined antimalarial-antibacterial suppository by interviewing 27 representatives of the three administrative levels (central government, regional, local) of the health sector; Study 2 investigated treatment-seeking behaviour and acceptability of this intervention at community level by interviewing 74 mothers in 2 villages. RESULTS AND CONCLUSIONS: Up to 92% of health representatives were in favour of introducing a new pre-referral strategy to tackle both malaria and non-malaria related severe illnesses in Guinea-Bissau, provided it was endorsed by international health authorities. The main obstacles to implementation were the very limited human and financial resources. In the two villages surveyed, 44% of the mothers associated severe illness with fever only, or fever plus one additional symptom. Mothers' judgement of severity and ensuing decisions were not specific for serious illness, indicating that initial training to recognize signs of severe disease and treatment availability for non-severe, fever-associated symptoms will be required to prevent overuse of a new intervention designed as a pre-referral treatment for severely ill children. Level C health centres were the first resort in both villages (50% and 87% of respondents respectively). This information is encouraging for the implementation of a pre-referral treatment.

A public private partnership to fight against malaria along the Chad-Cameroon pipeline corridor: I. Baseline data on socio-anthropological aspects, knowledge, attitudes and practices of the population concerning malaria.

BACKGROUND: Malaria is ranked as the major public health problem in Cameroon, representing 50% of illness in less than five year old children, 40-45% of medical consultation and 40% of the annual home income spent on health. The Cameroon Oil Transportation Company (COTCO) that exploits the Chad-Cameroon pipeline in Cameroon territory, initiated in 2010, a public private partnership project to control malaria along the pipeline corridor. A research component was included in the project so as to guide and evaluate the control measures applied in this pipeline corridor. This study presents the baseline socio-anthropological data as well as the knowledge, attitudes and practices of the local population concerning malaria, its transmission, management and prevention. METHODS: A descriptive cross-sectional survey was undertaken in four sentinel sites (one site per ecological zone) along the Chad-Cameroon pipeline corridor. Three structured questionnaires were used for the survey. Two of them were addressed to the heads of households (one for census and the other to collect information concerning the characteristics of houses and living conditions in households as well as their knowledge, attitudes and practices concerning malaria). The last questionnaire was used to collect information on malaria management and prevention. It was addressed to women who had delivered a living child within the past three years. Interviewers were recruited from each village and trained for two consecutive days on how to fill the different questionnaires. All data were analysed at 5% significant level using Epi-Info, SPSS and Cs PRO 4.0 STATA. Values of p ≤ 0.05 were considered statistically significant. RESULTS: Interviews were conducted in 2597 households (Bipindi 399, Bélabo 835, in Meidougou 820 and Dompta 543). Whatever the study site, 50% of the heads of household were workers of the agro-pastoral sector. Most of the heads of household were men (average 77.4% for men and 22.6% for females). The walls of households were mostly made-up of earth blocks and access to media was low. There were significant differences between mean ages and educational level of the heads of household. Significant differences were also observed between the characteristics of houses and the sites located in the southern regions (Bipindi and Bélabo) and those located in the northern regions (Meidougou and Dompta). The later household heads were younger and less educated than those in the other regions.In most of the study sites, paracetamol was cited as the first intention drug for malaria treatment, followed by chloroquine, a banned drug. More than half of the households studied had a correct knowledge of malaria and its mode of transmission: 120/155 (77.1%) in Bipindi, 244/323 (74.5%) in Bélabo, 171/235 (72.8%) in Meidougou and 118/218 (54.1%) in Dompta. Fever and headache were the malaria signs/symptoms most often cited by the households. An important percentage of pregnant women did not take any malaria prophylaxis during their last pregnancy (up to 43.4% in Bélabo). CONCLUSION: In all the study sites, there were conditions that indicated the all year round transmission of malaria (characteristics of houses and limited access to media making sensitization campaigns difficult). In general, most households had a good knowledge of malaria and its mode of transmission. However, malaria treatment drugs were most often inappropriate. In this study, recommendations were made in order to guide the implementation of control measures.

Management of uncomplicated malaria in febrile under five-year-old children by community health workers in Madagascar: reliability of malaria rapid diagnostic tests.

BACKGROUND: Early diagnosis, as well as prompt and effective treatment of uncomplicated malaria, are essential components of the anti-malaria strategy in Madagascar to prevent severe malaria, reduce mortality and limit malaria transmission. The purpose of this study was to assess the performance of the malaria rapid diagnostic tests (RDTs) used by community health workers (CHWs) by comparing RDT results with two reference methods (microscopy and Polymerase Chain Reaction, PCR). METHODS: Eight CHWs in two districts, each with a different level of endemic malaria transmission, were trained to use RDTs in the management of febrile children under five years of age. RDTs were performed by CHWs in all febrile children who consulted for fever. In parallel, retrospective parasitological diagnoses were made by microscopy and PCR. The results of these different diagnostic methods were analysed to evaluate the diagnostic performance of the RDTs administered by the CHWs. The stability of the RDTs stored by CHWs was also evaluated. RESULTS: Among 190 febrile children with suspected malaria who visited CHWs between February 2009 and February 2010, 89.5% were found to be positive for malaria parasites by PCR, 51.6% were positive by microscopy and 55.8% were positive by RDT. The performance accuracy of the RDTs used by CHWs in terms of sensitivity, specificity, positive and negative predictive values was greater than 85%. Concordance between microscopy and RDT, estimated by the Kappa value was 0.83 (95% CI: 0.75-0.91). RDTs stored by CHWs for 24 months were capable of detecting Plasmodium falciparum in blood at a level of 200 parasites/µl. CONCLUSION: Introduction of easy-to-use diagnostic tools, such as RDTs, at the community level appears to be an effective strategy for improving febrile patient management and for reducing excessive use of anti-malarial drugs.

[Chronicle of a death foretold: the fateful fate of french tropical medicine disciplines and its consequences in the fight against health inequalities in Africa]. / Chronique d'une mort annoncée : le destin funeste des disciplines de médecine tropicale françaises et ses conséquences dans la lutte contre les inégalités sanitaires en Afrique.

Since the end of the 1990s, we have witnessed a slow evolution in France leading to the disappearance of disciplines related to tropical diseases. At the hospital level, this is reflected by the progressive inclusion of clinical services dedicated to the treatment of infectious and tropical diseases within an infectious diseases or internal medicine pole, and, in medical biology, by the replacement of parasitological biologists having acquired a specialization in mycology, by mycological biologists having acquired a specialization in parasitology. This orientation may seem normal, the reduction of skills in parasitological and clinical diagnosis being linked to the success of hygiene and food control measures, which have led to the virtual disappearance, in our country, of autochthonous parasitic diseases such as fasciolosis, taeniasis, or amoebiasis. Priority is therefore given to mycology, especially respiratory infections, which are predominant in protected and aging populations. However, should this be done at the expense of diagnostic and treatment skills for diseases affecting populations in countries with limited resources?

Unusual transmission of Plasmodium falciparum, Bordeaux, France, 2009.

Plasmodium falciparum malaria is usually transmitted by mosquitoes. We report 2 cases in France transmitted by other modes: occupational blood exposure and blood transfusion. Even where malaria is not endemic, it should be considered as a cause of unexplained acute fever.

The initial pharmaceutical development of an artesunate/amodiaquine oral formulation for the treatment of malaria: a public-private partnership.

BACKGROUND: Artemisinin-based combination therapy is currently recommended worldwide for the treatment of uncomplicated malaria. Fixed-dose combinations are preferred as they favour compliance. This paper reports on the initial phases of the pharmaceutical development of an artesunate-amodiaquine (ASAQ) bilayer co-formulation tablet, undertaken following pre-formulation studies by a network of scientists and industrials from institutions of both industrialized and low income countries. METHODS: Pharmaceutical development was performed by a research laboratory at the University Bordeaux Segalen, School of Pharmacy, for feasibility and early stability studies of various drug formulations, further transferred to a company specialized in pharmaceutical development, and then provided to another company for clinical batch manufacturing. The work was conducted by a regional public-private not-for-profit network (TropiVal) within a larger Public Private partnership (the FACT project), set up by WHO/TDR, Médecins Sans Frontières and the Drugs for Neglected Disease initiative (DNDi). RESULTS: The main pharmaceutical goal was to combine in a solid oral form two incompatible active principles while preventing artesunate degradation under tropical conditions. Several options were attempted and failed to provide satisfactory stability results: incorporating artesunate in the external phase of the tablets, adding a pH regulator, alcoholic wet granulation, dry granulation, addition of an hydrophobic agent, tablet manufacturing in controlled conditions. However, long-term stability could be achieved, in experimental batches under GMP conditions, by physical separation of artesunate and amodiaquine in a bilayer co-formulation tablet in alu-alu blisters. Conduction of the workplan was monitored by DNDi. CONCLUSIONS: Collaborations between research and industrial groups greatly accelerated the process of development of the bi-layered ASAQ tablet. Lack of public funding was the main obstacle hampering the development process, and no intellectual property right was claimed. This approach resulted in a rapid technology transfer to the drug company Sanofi-Aventis, finalizing the process of development, registration and WHO pre-qualification of the fixed-dose co-formulation together with DNDi. The bi-layered tablet is made available under the names of Coarsucam® and Artesunate amodiaquine Winthrop®, Sanofi-Aventis. The issue related to the difficulty of public institutions to valorise their participation in such initiative by lack of priority and funding of applied research is discussed.

Diagnostics and the neglected tropical diseases roadmap: setting the agenda for 2030.

Accurate and reliable diagnostic tools are an essential requirement for neglected tropical diseases (NTDs) programmes. However, the NTD community has historically underinvested in the development and improvement of diagnostic tools, potentially undermining the successes achieved over the last 2 decades. Recognizing this, the WHO, in its newly released draft roadmap for NTD 2021-2030, has identified diagnostics as one of four priority areas requiring concerted action to reach the 2030 targets. As a result, WHO established a Diagnostics Technical Advisory Group (DTAG) to serve as the collaborative mechanism to drive progress in this area. Here, the purpose and role of the DTAG are described in the context of the challenges facing NTD programmes.

Quinine-resistant malaria in traveler returning from Senegal, 2007.

We describe clinical and parasitologic features of in vivo and in vitro Plasmodium falciparum resistance to quinine in a nonimmune traveler who returned to France from Senegal in 2007 with severe imported malaria. Clinical quinine failure was associated with a 50% inhibitory concentration of 829 nmol/L. Increased vigilance is required during treatment follow-up.

The Influence of Vitamin D on Neurodegeneration and Neurological Disorders: A Rationale for its Physio-pathological Actions.

Vitamin D is a steroid hormone implicated in the regulation of neuronal integrity and many brain functions. Its influence, as a nutrient and a hormone, on the physiopathology of the most common neurodegenerative diseases is continuously emphasized by new studies. This review addresses what is currently known about the action of vitamin D on the nervous system and neurodegenerative diseases such as Multiple Sclerosis, Alzheimer's disease, Parkinson's disease and Amyotrophic Lateral Sclerosis. Further vitamin D research is necessary to understand how the action of this "neuroactive" steroid can help to optimize the prevention and treatment of several neurological diseases.

Treatment of malaria from monotherapy to artemisinin-based combination therapy by health professionals in rural health facilities in southern Cameroon.

BACKGROUND: One year after the adoption of artesunate-amodiaquine (AS/AQ) as first-line therapy for the treatment of uncomplicated malaria, this study was designed to assess the treatment practices regarding anti-malarial drugs at health facilities in four rural areas in southern Cameroon. METHODS: Between April and August 2005, information was collected by interviewing fifty-two health professionals from twelve rural health facilities, using a structured questionnaire. RESULTS: In 2005, only three anti-malarial drugs were used in rural health facilities, including: amodiaquine, quinine and sulphadoxine-pyrimethamine. Only 2.0% of the health professionals prescribed the recommended AS/AQ combination. After reading the treatment guidelines, 75.0% were in favour of the treatment protocol with the following limitations: lack of paediatric formulations, high cost and large number of tablets per day. Up to 21.0% of professionals did not prescribe AS/AQ because of the level of adverse events attributed to the use of amodiaquine as monotherapy. CONCLUSION: The present study indicates that AS/AQ was not available in the public health facilities at the time of the study, and health practitioners were not informed about the new treatment guidelines. Results of qualitative analysis suggest that prescribers should be involved as soon as possible in projects related to the optimization of treatment guidelines and comply with new drugs. Adapted formulations should be made available at the international level and implemented locally before new drugs and treatments are proposed through a national control programme. This baseline information will be useful to monitor progresses in the implementation of artemisinin-based combination therapy in Cameroon.

Treatment of malaria from monotherapy to artemisinin-based combination therapy by health professionals in urban health facilities in Yaoundé, central province, Cameroon.

BACKGROUND: After adoption of artesunate-amodiaquine (AS/AQ) as first-line therapy for the treatment of uncomplicated malaria by the malaria control programme, this study was designed to assess the availability of anti-malarial drugs, treatment practices and acceptability of the new protocol by health professionals, in the urban health facilities and drugstores of Yaoundé city, Cameroon. METHODS: Between April and August 2005, retrospective and current information was collected by consulting registers and interviewing health practitioners in urban health facilities using a structured questionnaire. RESULTS: In 2005, twenty-seven trade-named drugs have been identified in drugstores; quinine tablets (300 mg) were the most affordable anti-malarial drugs. Chloroquine was restricted to food market places and no generic artemisinin derivative was available in public health centres. In public health facilities, 13.6% of health professionals were informed about the new guidelines; 73.5% supported the use of AS-AQ as first-line therapy. However, 38.6% apprehended its use due to adverse events attributed to amodiaquine. Malaria treatment was mainly based on the diagnosis of fever. Quinine (300 mg tablets) was the most commonly prescribed first-line anti-malarial drug in adults (44.5%) and pregnant women (52.5%). Artequin was the most cited artemsinin-based combination therapy (ACT) (9.9%). Medical sales representatives were the main sources of information on anti-malarials. CONCLUSION: The use of AS/AQ was not implemented in 2005 in Yaoundé, despite the wide range of anti-malarials and trade-named artemisinin derivatives available. Nevertheless, medical practitioners will support the use of this combination, when it is available in a paediatric formulation, at an affordable price. Training, information and participation of health professionals in decision-making is one of the key elements to improve adherence to new protocol guidelines. This baseline information will be useful to monitor progress in ACT implementation in Cameroon.

Determination of artesunate using reversed-phase HPLC at increased temperature and ELSD detection.

Artesunate (ART) determination can be performed by evaporative light scattering detection with mobile phase composed of CH(3)CN/HCOOH 0.01 M (40:60 v/v; pH 2.85). Evaporative light scattering detection instead of UV detection allowed to improve the sensitivity and the LOD. However, the evaporative light scattering detection response of dihydro-artemisinin appears weaker than for ART, whereas with UV detection the response of ART and dihydroartemisinin seemed similar. Constant analysis time was obtained on using the mobile phase with a flow rate of 0.5 mL/min and column temperature at 60 degrees C instead of 0.7 mL/min at room temperature. This led to less solvent consumption. Moreover, decrease in the flow rate and increase in the column temperature were advantageous for higher sensitivity with both evaporative light scattering detection and UV detection. ART determination in rectal gel and suppositories were compared with these different detection modes and similar results were obtained.

Nucleoside-lipid-based nanocarriers for methylene blue delivery: potential application as anti-malarial drug.

Nucleolipid supramolecular assemblies are promising Drug Delivery Systems (DDS), particularly for nucleic acids. Studies based on negatively and positively charged nucleolipids (diC16dT and DOTAU, respectively) demonstrated appropriate stability, safety, and purity profile to be used as DDS. Methylene Blue (MB) remains a good antimalarial drug candidate, and could be considered for the treatment of uncomplicated or severe malaria. However, the development of MB as an antimalarial drug has been hampered by a high dose regimen required to obtain a proper effect, and a short plasmatic half life. We demonstrated that nanoparticles formed by nucleolipid encapsulation of MB using diC16dT and DOTAU (MB-NPs) is an interesting approach to improve drug stability and delivery. MB-NPs displayed sizes, PDI, zeta values, and colloidal stability allowing a possible use in intravenous formulations. Nanoparticles partially protected MB from oxido-reduction reactions, thus preventing early degradation during storage, and allowing prolongated pharmacokinetic in plasma. MB-NPs' efficacy, tested in vitro on sensitive or multidrug resistant strains of Plasmodium falciparum, was statistically similar to MB alone, with a slightly lower IC50. This nucleolipid-based approach to protect drugs against degradation represents a new alternative tool to be considered for malaria treatment.

A role of IgE and CD23/NO immune pathway in age-related resistance of Lewis rats to Plasmodium berghei Anka?

In contrast to young rats, adult rats given i.p. Plasmodium berghei Anka (PbA) control the parasitaemia and repair their anaemia. Here, we investigated whether IgE and CD23/NO immune pathway could be implicated in this age-related resistance of adult rats to PbA. Eight-week-old rats displayed significantly higher levels of plasma total IgE (p=0.01) and soluble CD23 (p=0.003) during the peak of parasitaemia, compared to 4-week-old rats. IgE Fc-binding antibody or aminoguanidine administration to parasitized 8-week-old rats slightly delayed blood parasite clearance or exacerbated anaemia. These data suggest that IgE and CD23/NO could play an important role in the resistance of adult rats experiencing PbA primary intraerythrocytic development.

Transition metal-free addition of ketones or nitriles to 1,3-dienes.

The simpler the better (or going green): The first examples of the catalytic addition of 1,3-dienes to simple ketones or nitriles are described. These reactions can be effected on a kilogram scale, representing the shortest access featuring a perfect atom economy to molecules of interest in the perfume industry.

Evaluation of FRET real-time PCR assay for rapid detection and differentiation of Plasmodium species in returning travellers and migrants.

BACKGROUND: A simple real-time PCR assay using one set of primer and probe for rapid, sensitive and quantitative detection of Plasmodium species, with simultaneous differentiation of Plasmodium falciparum from the three other Plasmodium species (Plasmodium vivax, Plasmodium ovale and Plasmodium malariae) in febrile returning travellers and migrants was developed and evaluated. METHODS: Consensus primers were used to amplify a species-specific region of the multicopy 18S rRNA gene, and fluorescence resonance energy transfer hybridization probes were used for detection in a LightCycler platform (Roche). The anchor probe sequence was designed to be perfect matches to the 18S rRNA gene of the fourth Plasmodium species, while the acceptor probe sequence was designed for P. falciparum over a region containing one mismatched, which allowed differentiation of the three other Plasmodium species. The performance characteristics of the real-time PCR assay were compared with those of conventional PCR and microscopy-based diagnosis from 119 individuals with a suspected clinical diagnostic of imported malaria. RESULTS: Blood samples with parasite densities less than 0.01% were all detected, and analytical sensitivity was 0.5 parasite per PCR reaction. The melt curve means Tms (standard deviation) in clinical isolates were 60.5 degrees C (0.6 degrees C) for P. falciparum infection and 64.6 degrees C (1.8 degrees C) for non-P. falciparum species. These Tms values of the P. falciparum or non-P. falciparum species did not vary with the geographic origin of the parasite. The real-time PCR results correlated with conventional PCR using both genus-specific (Kappa coefficient: 0.95, 95% confidence interval: 0.9 - 1) or P. falciparum-specific (0.91, 0.8 - 1) primers, or with the microscopy results (0.70, 0.6 - 0.8). The real-time assay was 100% sensitive and specific for differentiation of P. falciparum to non-P. falciparum species, compared with conventional PCR or microscopy. The real-time PCR assay can also detect individuals with mixed infections (P. falciparum and non-P. falciparum sp.) in the same sample. CONCLUSION: This real-time PCR assay with melting curve analysis is rapid, and specific for the detection and differentiation of P. falciparum to other Plasmodium species. The suitability for routine use of this assay in clinical diagnostic laboratories is discussed.

New ferrocenic pyrrolo[1,2-a]quinoxaline derivatives: synthesis, and in vitro antimalarial activity.

Following our search for antimalarial compounds, novel series of ferrocenic pyrrolo[1,2-a]quinoxaline derivatives 1-2 were synthesized from various substituted nitroanilines and tested for in vitro activity upon the erythrocytic development of Plasmodiumfalciparum strains with different chloroquine-resistance status. The pyrrolo[1,2-a]quinoxalines 1 were prepared in 6-8 steps through a regioselective palladium-catalyzed monoamination by coupling 4-chloropyrrolo[1,2-a]quinoxalines with 1,3-bis(aminopropyl)piperazine or -methylamine using Xantphos as the ligand. The ferrocenic bispyrrolo[1,2-a]quinoxalines 2 were prepared by reductive amination of previously described bispyrrolo[1,2-a]quinoxalines 9 with ferrocene-carboxaldehyde, by treatment with NaHB(OAc)(3). The best results were observed with ferrocenic pyrrolo[1,2-a]quinoxalines linked by a bis(3-aminopropyl)piperazine. Moreover, it was observed that a methoxy group on the pyrrolo[1,2-a]quinoxaline nucleus and no substitution on the terminal N-ferrocenylmethylamine function enhanced the pharmacological activity. Selected compounds 1b, 1f-h, 1l and 2a were tested for their ability to inhibit beta-haematin formation, the synthetic equivalent of hemozoin, by using the HPIA (heme polymerization inhibitory activity) assay. Of the tested compounds, only 2a showed a beta-haematin formation inhibition, but no inhibition of haem polymerization was observed with the other selected ferrocenic monopyrrolo[1,2-a]quinoxaline derivatives 1b, 1f-h and 1l, as the IC(50) values were superior to 10 equivalents.

In vitro release and stability of an artesunate rectal gel suitable for pediatric use.

The rectal route is indicated to treat patients with rapidly evolving malaria who cannot take oral medication to prevent progression to severe forms of the disease. Improvement can be made in terms of rectal bioavailability and stability of current formulations. We studied a new two-compartment, muco-adhesive gel formulation of artesunate which is adapted for use in children and storage in tropical climates. The formulation contains 50mg of artesunate per gram of gel. Because of its instability in aqueous solutions, artesunate is in the dry component of the gel with Carbopol and separate from the liquid phase until reconstitution. Artesunate is stable in the dry blend for 6 months at 45 degrees C and 60% RH. The gel should be used between 1 and 72 h after being reconstituted. Artesunate release was measured by with a rapid, simple and reliable HPLC-UV which allowed the analysis of artesunate and dihydroartemisinin with an analysis time at 3 min. The amount of artesunate released over 6h was 56 +/- 0.97%. Compared to the reference suspension, total release and dissolution efficiency were lower and rate of release was slower (time to 50% dissolution 271 +/- 21 min), probably because of the higher viscosity of the gel, but the drug release profiles were similar. The calculated in vitro release exponent (n) value suggested that artesunate is released from the gel by non-Fickian transport.