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Background: Recently, the essential oil (EO) of Ammodaucus leucotrichus has attracted particular attention in hemi-synthesis due to the reactivity of its main monoterpenes. Objective: In vitro cytotoxic and antileishmanial activities of the EO and hemi-synthesized compounds were evaluated, and an in-silico simulation was conducted. Methods: The EO was characterized by GC-MS. Two benzodiazepines (C1, C2), benzimidazole (C3), and Schiff base (C4) were hemi-synthesized by an in situ condensation of its major monoterpenes (perillaldehyde) with different amine derivatives. Synthesized compounds and the EO were evaluated for their cytotoxic activity against laryngeal carcinoma-Hep2 and rhabdomyosarcoma-RD cell lines and for their antileishmanial activity against Leishmania (L) major. Molecular docking was performed to pin the binding interactions of active molecules. Results: A significant cytotoxic effect of benzodiazepines C1 and C2 was noted against Hep2 cells (IC50/C1 = 39.48 ±0.7 μM, IC50/C2 = 48.82±1.33 μM) and RD (IC50/C1 = 15.96±1.99 μM; IC50/C2 = 74.3±2.44 μM), while the EO highly inhibited Hep2 cell lines (IC50/EO = 17.3±0.85 μg/mL). C4 strongly inhibited L. major growth with an IC50 value of 8.00±1.37 Μμ. The docking scores of ligand-C4 on L. major pteridine reductase and L. major methionyl-tRNA synthetase and ligands-(C1, C2) on the human protein kinase and epidermal growth factor kinase presented significant affinity to the receptor active sites (ΔG from -7.7 to -8.8 kcal/mol). Conclusion: The cytotoxic effect of derivatives C1, C2, and EO, as well as the anti-parasitic effect of C4, may suggest them as effective bioactive agents or pharmaceutical probes.

Leishmania (L.) infantum strains, isolated from varying hosts and clinical manifestations (cutaneous, visceral and canine leishmaniasis), were investigated in order to understand the genetic polymorphisms within this species in Algeria and Tunisia. Two DNA-based typing methods were tested in order to evaluate their effectiveness against Multilocus enzyme electrophoresis (MLEE), widely considered as the reference method for Leishmania parasite typing. On the other hand, MLEE is cumbersome, high-cost, time consuming and frequently does not detect intra-species genetic polymorphisms. In this work, we used two molecular target regions to discriminate L. infantum strains, Internal transcribed spacer 1 (ITS1) and the cysteine proteinase B (cpb). The ITS1 region offers good resolution for Leishmania discrimination but does not spotlight intra-species polymorphisms. In contrast, cpbE and cpbF PCR-Sequencing demonstrated a certain variability within CL and VL Algerian and Tunisian L. infantum isolates. Following phylogenetic analyses of 44 L. infantum isolates, two main groups were identified, a group with 39 bp deletion in the cpb sequence, composed of cutaneous, visceral and canine isolates from both countries with no significant clinical or geographic distribution; these samples were typed as MON-1, MON-24, and MON-80 zymodemes. A second group which presents a clear clusterization of Tunisian cutaneous strains belonging to the L. infantum MON-24. This group, with no deletion in the mature domain of the cpb gene sequence, should be further explored with a higher number of samples.

Background Dipeptidyl peptidase III (DPPIII) member of M49 peptidase family is a zinc-dependent metallopeptidase that cleaves dipeptides sequentially from the N-terminus of its substrates. In Leishmania, DPPIII, was reported with other peptidases to play a significant role in parasites’ growth and survival. In a previous study, we used a coding sequence annotated as DPPIII to develop and evaluate a PCR assay that is specific to dermotropic Old World (OW) Leishmania species. Thus, our objective was to further assess use of this gene for Leishmania species identification and for phylogeny, and thus for diagnostic and molecular epidemiology studies of Old World Leishmania species. Methodology Orthologous DDPIII genes were searched in all Leishmania genomes and aligned to design PCR primers and identify relevant restriction enzymes. A PCR assays was developed and seventy-two Leishmania fragment sequences were analyzed using MEGA X genetics software to infer evolution and phylogenetic relationships of studied species and strains. A PCR-RFLP scheme was also designed and tested on 58 OW Leishmania strains belonging to 8 Leishmania species and evaluated on 75 human clinical skin samples. Findings Sequence analysis showed 478 variable sites (302 being parsimony informative). Test of natural selection (dN-dS) (-0.164, SE = 0.013) inferred a negative selection, characteristic of essential genes, corroborating the DPPIII importance for parasite survival. Inter- and intra-specific genetic diversity was used to develop universal amplification of a 662bp fragment. Sequence analyses and phylogenies confirmed occurrence of 6 clusters congruent to L. major, L. tropica, L. aethiopica, L. arabica, L. turanica, L. tarentolae species, and one to the L. infantum and L. donovani species complex. A PCR-RFLP algorithm for Leishmania species identification was designed using double digestions with HaeIII and KpnI and with SacI and PvuII endonucleases. Overall, this PCR-RFLP yielded distinct profiles for each of the species L. major, L. tropica, L. aethiopica, L. arabica and L. turanica and the L. (Sauroleishmania) L. tarentolae. The species L. donovani, and L. infantum shared the same profile except for strains of Indian origin. When tested on clinical samples, the DPPIII PCR showed sensitivities of 82.22% when compared to direct examination and was able to identify 84.78% of the positive samples. Conclusion The study demonstrates that DPPIII gene is suitable to detect and identify Leishmania species and to complement other molecular methods for leishmaniases diagnosis and epidemiology. Thus, it can contribute to evidence-based disease control and surveillance., Author summary Leishmaniases correspond to a group of neglected tropical diseases caused by protozoan parasites members of more than 20 Leishmania species. Leishmaniases are epidemiologically complex diseases. Their complexity relates to the diversity of species and transmission cycle components, often poorly elucidated. Risk factors for changing eco-epidemiological profiles include environmental and climate changes, migrations and conflicts, contributing to leishmaniases emergence in disease-free areas, leading to co-sympatry of the major pathogens in the same transmission areas and even foci. Taxonomical identification of the parasites is a central issue for patient management, molecular epidemiology and thus disease control and surveillance. Thus, development of adequate specific and sensitive DNA tools to identify and classify Leishmania parasites for surveillance and control remains a research priority. The DPPIII gene is an essential gene conserved in all Leishmania species. By comparative sequence analyses of the DPPIII gene fragments and the development of DPPIII-based PCR RFLP assays, we showed its potential for molecular diagnosis, epidemiology and taxonomy. We conclude that this molecular marker can be used to complement other molecular methods for OW Leishmania species identification and discrimination and can contribute to evidence- based disease control and surveillance.

Introduction: Leishmaniasis is a severe disease that presents a real public health problem worldwide. Antileishmanial therapy remains expensive with intolerable side effects; therefore, it is essential to develop tolerable antileishmanial medications with a selective efficacy. Methods: In this study, the leishmanicidal activities of seven Algerian plant extracts, selected based on either ethnobotanical or chemotaxonomical data, were screened for their antileishmanial activity against promastigotes and amastigotes of cutaneous leishmaniasis agent Leishmania major (MON 25), and visceral leishmaniasis agent Leishmania infantum (MON 1). The cytotoxic activity against human monocytes THP1 was also determined. Results: In both species, amastigotes showed more sensitivity to the extracts than promastigotes. Erica arborea flower (IC50=43,98 𝜇g/mL), Marrubium vulgare leaves (IC50=45,84 𝜇g/mL) and Artemisia herba-alba Asso aerial parts (IC50=55,21 𝜇g/mL) had an almost similar inhibitory effect on L. major promastigote. Marrubium vulgare leaves (IC50=35,63 𝜇g/mL) was most effective against L. infantum promastigotes. Besides, these extracts exhibited low selectivity indices. The best results were obtained with M. vulgare on both L. major and L. infantum promastigotes (IC50s of 45,84 µg/ml and 35,63 µg/ml), and amastigotes (IC50s of 32,15 µg/ml and 18,64 µg/ml). The selectivity index was above two (2.34 for L. major and 3.01 for L. infantum), calculated based on the acceptable cytotoxic effect of M. vulgare on human macrophage cell line (CC50=107,45 µg/ml). Conclusion: Out of the seven methanol extracts tested against promastigotes of L. major and L. infantum, three showed promising activity with potent leishmanicidal effect and acceptable selectivity indices on L. major and L. infantum.

International audience; AbstractPurposeSurra is a zoonotic disease caused by Trypanosoma evansi (Trypanozoon), a salivary trypanosome native to Africa which affects a wide range of mammals worldwide and causes mortality and significant economic loss. The present study was devoted to the molecular characterization of T. evansi derived from naturally infected dromedary camels in Algeria.MethodsA total of 148 blood samples were collected from mixed age camels living in one of four geographic regions (Ouargla, El Oued, Biskra and Ghardaia) of Algeria. Samples underwent PCR amplification and sequencing of the internal transcribed spacer 1 (ITS1) complete sequence.ResultsDNA of Trypanosoma spp. was found in 19 camels (12.84%). Trypanosoma spp. molecular positivity was not affected by sex (p = 0.50), age (p = 0.08), or geographic location (p = 0.12). Based on multiple sequence alignment of the obtained DNA sequences with representative T. evansi ITS1 sequences available globally, the Algerian sequences were grouped within four different haplotypes including two which were original.ConclusionResults of this study provide preliminary data on which future studies of genetic diversity and molecular epidemiology of T. evansi can be based.

Algeria is one of the most endemic countries for cutaneous and visceral forms of leishmaniosis. Strikingly, with more than 21,000 annual cases of cutaneous leishmaniosis recorded in 2010, the disease has a major public health impact.

La PCR nichee a ete utilisee pour evaluer son apport et ses limites dans le diagnostic du paludisme et pour evaluer la performance des microscopistes dans la surveillance de la maladie dans le Sud de l’Algerie. Durant la periode de 2010-2015, 112 patients dont 93 febriles et 19 asymptomatiques originaires d’Afrique subsaharienne ont ete adresses au laboratoire de l’hopital de la wilaya de Tamanrasset pour le diagnostic du paludisme. Une partie du sang preleve a la pulpe du doigt a servi pour la confection de frottis et de goutte epaisse et l’autre partie a ete absorbee dans du papier filtre pour le diagnostic moleculaire. La PCR nichee a permis de detecter le parasite dans 63 echantillons contre 53 a l’examen microscopique, de mettre en evidence 11 infections mixtes et de diagnostiquer 6 cas positifs non detectes a la microscopie. Deux echantillons negatifs a la PCR nichee avaient ete declares positifs a l’examen direct. La PCR nichee est plus sensible que l’examen direct dans la detection des parasitemies infra microscopiques et les infections mixtes.

Background: Based on the reporting of the presence of stripped mosquitoes by a citizen in the Algiers residential neighborhood of Bir-Khadem, where residents experienced huge daytime mosquito nuisance an entomological inves-tigation was carried out in July 2016. Methods: Ovitraps and BG sentinel traps baited with Lure were used during three consecutive days to collect adult mosquitoes. Eighteen residential houses of the Bir-Khadem neighborhood were also inspected to search larvae breed-ing sites such as water fountains, baskets and flowerpots. Results: A total of 57 Aedes albopictus specimens were collected in five villas, consisting of 21 eggs, 20 larvae and 16 adults. Conclusion: This is the first record of this invasive species in Algiers.

BackgroundThe Mediterranean Basin is historically a hotspot for trade, transport, and migration. As a result, countries surrounding the Mediterranean Sea share common public health threats. Among them are vector-borne diseases, and in particular, mosquito-borne viral diseases are prime candidates as (re)emerging diseases and are likely to spread across the area. Improving preparedness and response capacities to these threats at the regional level is therefore a major issue. The implementation of entomological surveillance is, in particular, of utmost importance. Guidance in designing entomological surveillance systems is critical, and these systems may pursue different specific objectives depending on the disease. The purpose of the proposed review is to draw up guidelines for designing effective and sustainable entomological surveillance systems in order to improve preparedness and response. However, we make it clear that there is no universal surveillance system, so the thinking behind harmonisation is to define evidence-based standards in order to promote best practises, identify the most appropriate surveillance activities, and optimise the use of resources. Such guidance is aimed at policymakers and diverse stakeholders and is intended to be used as a framework for the implementation of entomological surveillance programmes. It will also be useful to collaborate and share information with health professionals involved in other areas of disease surveillance. Medical entomologists and vector control professionals will be able to refer to this report to advocate for tailored entomological surveillance strategies. The main threats targeted in this review are the vectors of dengue virus, chikungunya virus, Zika virus, West Nile virus, and Rift Valley fever virus. The vectors of all these arboviruses are mosquitoes.MethodsCurrent knowledge on vector surveillance in the Mediterranean area is reviewed. The analysis was carried out by a collaboration of the medical entomology experts in the region, all of whom belong to the MediLabSecure network, which is currently funded by the European Union and represents an international effort encompassing 19 countries in the Mediterranean and Black Sea region.FindingsRobust surveillance systems are required to address the globalisation of emerging arboviruses. The prevention and management of mosquito-borne viral diseases must be addressed in the prism of a One Health strategy that includes entomological surveillance as an integral part of the policy. Entomological surveillance systems should be designed according to the entomological and epidemiological context and must have well-defined objectives in order to effect a tailored and graduated response. We therefore rely on different scenarios according to different entomological and epidemiological contexts and set out detailed objectives of surveillance. The development of multidisciplinary networks involving both academics and public authorities will provide resources to address these health challenges by promoting good practises in surveillance (identification of surveillance aims, design of surveillance systems, data collection, dissemination of surveillance results, evaluation of surveillance activities) and through the sharing of effective knowledge and information. These networks will also contribute to capacity building and stronger collaborations between sectors at both the local and regional levels. Finally, concrete guidance is offered on the vector of the main arbovirus based on the current situation in the area.

International audience; Antimicrobial resistance (AMR) threatens the prevention and treatment of infections caused by a large range of microorganisms. Leishmania is not an exception and treatment failure due to drug-resistant organisms is increasingly reported. Currently, no molecular methods and marker are validated to track drug-resistant organism and antimicrobial susceptibility tests are roughly not amenable to a clinical setting. Taking these facts into account, it is essential to reflect on ways to translate basic knowledge into methodologies aimed to diagnose leishmania drug resistance. As a matter of fact, a meta-analysis of the literature discloses the reliability of the promastigotes antimicrobial susceptibility tests (AST) to predict intracellular amastigotes susceptibility status. Promastigote cultures that are easy to perform, typically inexpensive and amenable to standardization should represent a candidate to diagnose resistance. Using AST performed on promastigote, we propose a way to improve leishmania drug resistance diagnosis in the framework of guidance and guideline of the bacterial drug resistance diagnosis. In this review, we highlight challenges that remained and discuss the definition of clinical breakpoints, including the epidemiological cutoff (ECOFF), to track drug-resistant isolates. Our analysis paves the ways to standardize and analyze anti-leishmania susceptibility tests output in order to guide the characterization of drug-resistant isolates, the clinical decision during treatment and the search for new molecular markers.

Protozoan parasites of the genus Leishmania cause severe human and veterinary diseases worldwide, termed leishmaniases. A hallmark of Leishmania biology is its capacity to adapt to a variety of unpredictable fluctuations inside its human host, notably pharmacological interventions, thus, causing drug resistance. Here we investigated mechanisms of environmental adaptation using a comparative genomics approach by sequencing 10 new clinical isolates of the L. donovani, L. major, and L. tropica complexes that were sampled across eight distinct geographical regions. Our data provide new evidence that parasites adapt to environmental change in the field and in culture through a combination of chromosome and gene amplification that likely causes phenotypic variation and drives parasite fitness gains in response to environmental constraints. This novel form of gene expression regulation through genomic change compensates for the absence of classical transcriptional control in these early-branching eukaryotes and opens new venues for biomarker discovery., Protozoan parasites of the genus Leishmania adapt to environmental change through chromosome and gene copy number variations. Only little is known about external or intrinsic factors that govern Leishmania genomic adaptation. Here, by conducting longitudinal genome analyses of 10 new Leishmania clinical isolates, we uncovered important differences in gene copy number among genetically highly related strains and revealed gain and loss of gene copies as potential drivers of long-term environmental adaptation in the field. In contrast, chromosome rather than gene amplification was associated with short-term environmental adaptation to in vitro culture. Karyotypic solutions were highly reproducible but unique for a given strain, suggesting that chromosome amplification is under positive selection and dependent on species- and strain-specific intrinsic factors. We revealed a progressive increase in read depth towards the chromosome ends for various Leishmania isolates, which may represent a nonclassical mechanism of telomere maintenance that can preserve integrity of chromosome ends during selection for fast in vitro growth. Together our data draw a complex picture of Leishmania genomic adaptation in the field and in culture, which is driven by a combination of intrinsic genetic factors that generate strain-specific phenotypic variations, which are under environmental selection and allow for fitness gain.

The increasing globalisation of trades, human movements and environmental changes facilitate the introduction and the establishment of the invasive Asian tiger mosquito Aedes albopictus outside its native geographical area. Alerted by the complaints about mosquito biting which occurred daytime for the inhabitants of the seaside town Ain Turk (West of Algeria), an entomological survey was conducted in December 2015 to determine the origin of this nuisance. Among the collected mosquitoes, specimens of Ae. albopictus (2 males, 3 females and 3 pupae) were collected. This is the first observation of that invasive mosquito in the west of Algeria which confirms its presence and establishment in Mediterranean Africa.

International audience; Investigating new antimicrobial and antiparasitic components from Viperidae venoms represents an alternative therapeutic strategy. In this study, we report the characterization of a disintegrin isolated from Cerastes cerastes venom, exhibiting antiparasitic activity on Leishmania infantum promastigotes. Indeed, isolated disintegrin, referred to Disintegrin_Cc, induced 84.75% of parasiticidal activity and deep morphological alterations on the parasites. SDS-PAGE analysis indicated that this disintegrin was homogenous. This dimeric disintegrin of 14,193.97 Da contains an RGD domain and four intramolecular disulfide bridges. It presents a high percentage of identity with other related snake disintegrins. Predicted 3D structure indicated that this peptide shares partial homology with well-known active antimicrobial peptides. Disintegrin_Cc inhibited 80% of arachidonic acid-induced platelet aggregation. The obtained results suggest that the isolated molecule plays a dual role as a disintegrin and as an anti-leishmanial compound. This component could be useful as a drug in the treatment of leishmaniasis.

La leishmaniose viscerale (LV) constitue un probleme de sante publique en Tunisie. L’objectif de ce travail est d’actualiser les aspects epidemiologiques, cliniques et biologiques. L’etude a concerne tous les cas de LV enregistres a l’hopital de Kairouan entre 2004 et 2013. Les donnees suivantes ont ete recueillies chaque fois qu’elles etaient disponibles : sexe, âge, origine geographique, signes cliniques, parametres biologiques, resultats des examens specifiques de confirmation (myelogramme, serologie, culture, PCR) et identification iso-enzymatique des isolats. Deux cent quarante cas de LV ont ete recenses. La majorite des cas etaient d’origine rurale (87,1 %). La mediane de l’âge etait de 18 mois. Le sex-ratio etait de 1,03. La mediane du delai de diagnostic etait de 15 jours. Les signes cliniques a l’admission etaient domines par la splenomegalie (97,9 %), la fievre (79,9 %) et l’hepatomegalie (47,3 %). L’anemie (91,7 %), la thrombopenie (83,9 %) et la leucopenie (56,1 %) ont ete frequemment notees. La PCR etait la technique biologique la plus sensible (100 %) parmi celles utilisees pour la confirmation du diagnostic. Leishmania (L.) infantum MON-1 a ete le zymodeme le plus identifie des 43 isolats types (62,8 %). Les zymodemes MON-24 et MON-80, ont ete mis en evidence chez un nombre non negligeable de malades (25,6 % et 11,6 % respectivement). Notre etude a permis d’actualiser le profil epidemio-clinique et biologique de la LV infantile en Tunisie. Elle a montre un raccourcissement des delais de diagnostic. L’amelioration du pronostic de la maladie necessite cependant un diagnostic encore plus precoce. La PCR en temps reel s’avere une innovation d’un grand apport pour la prise en charge de la LV.

Human leishmaniases are widespread diseases with different clinical forms caused by about 20 species within the Leishmania genus. Leishmania species identification is relevant for therapeutic management and prognosis, especially for cutaneous and mucocutaneous forms. Several methods are available to identify Leishmania species from culture, but they have not been standardized for the majority of the currently described species, with the exception of multilocus enzyme electrophoresis. Moreover, these techniques are expensive, time-consuming, and not available in all laboratories. Within the last decade, mass spectrometry (MS) has been adapted for the identification of microorganisms, including Leishmania . However, no commercial reference mass-spectral database is available. In this study, a reference mass-spectral library (MSL) for Leishmania isolates, accessible through a free Web-based application (mass-spectral identification [MSI]), was constructed and tested. It includes mass-spectral data for 33 different Leishmania species, including species that infect humans, animals, and phlebotomine vectors. Four laboratories on two continents evaluated the performance of MSI using 268 samples, 231 of which were Leishmania strains. All Leishmania strains, but one, were correctly identified at least to the complex level. A risk of species misidentification within the Leishmania donovani , L. guyanensis , and L. braziliensis complexes was observed, as previously reported for other techniques. The tested application was reliable, with identification results being comparable to those obtained with reference methods but with a more favorable cost-efficiency ratio. This free online identification system relies on a scalable database and can be implemented directly in users' computers.

Les leishmanioses, maladies à transmission vectorielle liée au genre Phlebotomus, constituent un problème de santé publique en Algérie, essentiellement dans leur forme cutanée. Dans la région de Draa El Mizan (Kabylie), coexistent depuis long-temps laleishmaniose viscérale, et la forme cutanée liée àLeishmania infantum.Durant l’été 2013, une enquête entomologique a été menée à Draa El-Mizan, dans le but de réaliser un inventairefaunistique des phlébotomes à l’aide de pièges lumineux type CDC.Sur un total de 22.998 spécimens récoltés, un échantillon représentatif de 1500 individus a fait l’objet d’une identificationmorphologique par microscope optique.Le genre Phlebotomus est prédominant avec 97,41% des individus représentant 5 taxons où prévalent Phlebotomus perfiliewi (4,63%) et Phlebotomus perniciosus (19,4%). Le sex-ratio M/F global est de 1,39, mais en faveur des individus femelles pour l’espèce Phlebotomus perfiliewi (sex-ratio M/F=0,82).A Draa El Mizan, les conditions climatiques associées aux activités humaines de type pastorales entretiennent la prolifération du genre Phlebotomus inféodé à L. Infan-tum. Par ailleurs, l’utilisation des pièges lumineux type CDC a montré son intérêt dans la surveillance entomologique des maladies vectorielles.

Background: Leishmaniasis represents a serious public health problem in Algeria. The parasite, in the promastigote form, upon transfer by the infected vector to the vertebrate host, invades mononuclear macrophages and causes substantial human morbidity and mortality. Investigating new antimicrobial and antiparasitic components from Viperidae venoms represents an alternative therapeutic strategy for leishmaniasis treatment. Objective: In the present study, we report the characterization of a disintegrin, isolated from Cerastes cerastes venom, exhibiting antiparasitic activity on Leishmania infantum promastigotes. Methods: The active biomolecule, referred to as Disintegrin_Cc, was isolated by RP-HPLC chromatography. The in vitro antiparasitic activity of this molecule was evaluated on Leishmania infantum promastigotes. The isolated disintegrin was analyzed by SDS-PAGE for homogeneity and molecular weight determination and then subjected to MALDI-TOF MS/MS analysis. A 3D structure was predicted in silico using SWISS-Model. Results: Isolated Disintegrin_Cc induced deep morphological alterations on the parasites and a strong anti-leishmanial activity estimated to 84.75% of mortality. SDS-PAGE analysis indicated that this disintegrin was homogenous. This dimeric disintegrin of 14,193.97 Da contains an RGD domain and four intramolecular disulfide bridges. This biomolecule presents a high percentage of identity with other related types of snake disintegrin. Predicted 3D structure indicated that this peptide shares partial homology with well-known active antimicrobial peptides. Conclusion: This study demonstrated the leishmanicidal activity of Disintegrin_Cc. This molecule may be useful to design a new therapy against leishmaniasis.

Visceral and cutaneous leishmaniasis are the main endemic vector born diseases in Algeria. In the Hoggar region (extreme south of the country) human visceral leishmaniasis (HVL) is known to be sporadic but during the last decade the number of cases has increased significantly. In 2010, a peak of HVL cases was registered mostly among children. Therefore an entomological survey and a retrospective study on HVL cases were carried out in order to explore the transmission of the disease. Among the sand fly caught Phlebotomus bergeroti was the most frequent species (68%) followed by Sergentomyia schwetzi (22%). In this work we describe the presence of Phlebotomus (Paraphlebotomus) kazeruni for the first time in the Hoggar region.

En Algerie, la leishmaniose cutanee zoonotique a Leishmania major constitue un lourd fardeau pour la sante publique. On denombre en moyenne 10 000 nouveaux cas parmi les 15 millions de personnes exposees vivant en zone d’endemie. Le foyer de M’Sila, avec une incidence annuelle de 561,8 pour 100 000 habitants, est le plus important en Algerie apres le foyer historique de Biskra. Le reservoir principal de la maladie est Psamommys obesus, rongeur gerbillide, qui se nourrit exclusivement de plantes salees, les chenopodiacees, sous lesquelles ce dernier construit son terrier. Un des moyens de lutte contre la leishmaniose dans les regions sahariennes et pre-sahariennes, celui que l’etude atteste, est d’eliminer ces plantes autour des habitations sur un rayon de 300 metres. Dans le cadre d’un programme social de travaux d’utilite publique employant 396 jeunes chomeurs, cette experience pilote a ete menee en 2003 dans cinq communes les plus touchees dans la wilaya de M’Sila. 3 600 hectares ont ete traites avant la saison de transmission de la maladie qui debute au mois de mai. Une reduction de 31 % du nombre de cas de leishmaniose cutanee a ete notee, passant de 1 391 cas en 2003 contre 965 cas en 2004. Cette experience merite d’etre elargie a l’ensemble du territoire, pour mieux evaluer l’impact de cette methode de lutte dans la prevention de la maladie.

In Algeria,Leishmania infantum,Leishmania major, andLeishmania killicki(Leishmania tropica) are responsible for cutaneous leishmaniosis. We established a murine model ofL. killickiinfection to investigate its infective capacity, some immunophysiopathological aspects, and its suitability for pharmacological purposes. Following the injection ofL. majororL. killickimetacyclic promastigotes in the ear dermis of BALB/c mice, the course of infection was followed. The infection withL. killickicaused slower lesion formation than withL. major. The presence ofL. killickiorL. majorDNA and parasites was detected in the ear dermis and in lymph nodes, spleen, and liver. Lesions induced byL. killickiwere nonulcerative in their aspect, whereas those caused byL. majorwere highly ulcerative and necrotic, which matches well with the lesion phenotype reported in humans forL. killickiandL. major, respectively. The treatment ofL. killickilesions by injection of Glucantime® significantly reduced the lesion thickness and parasite burden. Ear dermal injection of BALB/c mice constitutes a model to study lesions physiopathology caused byL. killickiand presents interest forin vivoscreening of new compounds against this pathogen, emerging in Algeria.

Leishmania (L.) killicki (syn. L. tropica), which causes cutaneous leishmaniasis in Maghreb, was recently described in this region and identified as a subpopulation of L. tropica. The present genetic analysis was conducted to explore the spatio-temporal distribution of L. killicki (syn. L. tropica) and its transmission dynamics. To better understand the evolution of this parasite, its population structure was then compared with that of L. tropica populations from Morocco. In total 198 samples including 85 L. killicki (syn. L. tropica) (from Tunisia, Algeria and Libya) and 113 L. tropica specimens (all from Morocco) were tested. Theses samples were composed of 168 Leishmania strains isolated from human skin lesions, 27 DNA samples from human skin lesion biopsies, two DNA samples from Ctenodactylus gundi bone marrow and one DNA sample from a Phlebotomus sergenti female. The sample was analyzed by using MultiLocus Enzyme Electrophoresis (MLEE) and MultiLocus Microsatellite Typing (MLMT) approaches. Analysis of the MLMT data support the hypothesis that L. killicki (syn. L. tropica) belongs to the L. tropica complex, despite its strong genetic differentiation, and that it emerged from this taxon by a founder effect. Moreover, it revealed a strong structuring in L. killicki (syn. L. tropica) between Tunisia and Algeria and within the different Tunisian regions, suggesting low dispersion of L. killicki (syn. L. tropica) in space and time. Comparison of the L. tropica (exclusively from Morocco) and L. killicki (syn. L. tropica) population structures revealed distinct genetic organizations, reflecting different epidemiological cycles., Author Summary Leishmania killicki (syn. L. tropica) was discovered in 1986. Few studies have been conducted on this parasite exclusively described in Maghreb. Consequently, many elements on its epidemiology, transmission, population structure and dynamics remain unknown. To better understand the evolution of this parasite, its population structure has been compared with that of L. tropica populations from Morocco using Multilocus Enzyme Electrophoresis (MLEE) and MultiLocus Microsatellite Typing (MLMT) typing. MLMT data support the hypothesis that L. killicki (syn. L. tropica) belongs to the L. tropica complex despite the strong genetic differentiation between them. Despite the probable recent divergence between L. killicki (syn. L. tropica) and L. tropica, they seem to evolve differently. Indeed, L. killicki (syn. L. tropica) appears slightly polymorphic and highly structured in space and time, while L. tropica was genetically heterogeneous, slightly structured geographically and temporally. The different population structures revealed distinct genetic organizations, reflecting different epidemiological cycles. Several parameters could explain these opposite epidemiological and genetic patterns such as ecosystems, vectors and reservoirs.

Since a long time, Leishmania major and L. infantum foci in Algeria were geographically separated by the mountains of the Tell Atlas which represent a natural barrier. Recently, a new focus of cutaneous leishmaniasis (CL) has emerged in the village of El M’hir, located on the north side of the chain of the Tell Atlas, in the basin of the Soummam. During the period 2004–2010, 152 CL cases have been registered and 12 isolates were obtained from patients who declared never having been outside the village the last years. The identification of the parasites showed that all strains belonged to L major MON-25. Investigations on the reservoir hosts showed the presence of the sand rat (Psammomys obesus), for the first time, in this locality. Five strains isolated from this rodent belonged to L. major MON-25. The sand rat, which is usually observed around the chotts in the Saharan and steppe areas, acts as the main reservoir of L. major in Algeria. Its presence in the new focus of El M’hir is reported for the first time. Entomological surveys carried out in 2009 showed the predominance of two sandfly species: Phlebotomus papatasi and P. perniciosus. The first one is known as a vector of L major in the Algerian Sahara. This study highlights the spread of L. major from the arid zones towards the semi arid areas, particularly in the Soummam valley. Climate changes and desertification observed in the steppe area northern Sahara could play a role in the extension of the disease.

This bibliographic review reports the isoenzyme polymorphism of 1023 Leishmania infantum strains isolated from dogs that have been characterized by multilocus enzyme electrophoresis in the Leishmania Reference Centre of Montpellier, or in other laboratories, to which this typification technique has already been transferred. Between 1981 and 2010, a total of 12 zymodemes were identified around the Mediterranean basin: MON-1, MON-24, MON-34, MON-72, MON-77, MON-80, MON-98, MON-105, MON-108, MON-199, MON-199 var NP1130 and MON-281, of which 6 were present in Algeria. The zymodeme MON-1 was predominant (86.5% of the strains). The dog was confirmed as the main reservoir of L. infantum MON-1, while the reservoir of the other zymodemes has not yet been identified. The enzymatic polymorphism is relatively high in Algeria and in Spain in contrast to other Mediterranean countries. The reasons for this polymorphism are discussed.

Anopheles labranchiae Falleroni is the only member of the Maculipennis Group known to occur in northern Africa; however, confusion exists as to the taxonomic status of its junior synonym, An. sicaulti Roubaud (type locality: near Rabat, Morocco). Based on morphological and behavioural distinctions, it has been suggested that Moroccan populations have been isolated from other North African populations by the Atlas Mountains, and that Moroccan populations may represent An. sicaulti , originally described as a variety of An. maculipennis Meigen. DNA barcodes (658 bp of the mitochondrial COI gene) obtained from 89 An. maculipennis s.l . collected in Morocco ( n = 79) and Algeria ( n = 10) in 2007 and 2008 were used to determine if Moroccan populations are genetically isolated from those east of the Atlas Mountains (Algeria), and whether there is molecular evidence to support the presence of more than one member of the Maculipennis Group in the region. No evidence for speciation was found between Moroccan and Algerian populations, or within populations in northern Morocco. Moreover shared COI haplotypes between Algeria and Morocco indicate ongoing gene flow between populations in these countries, suggesting that the Atlas Mountains are not a boundary to gene flow in An. labranchiae . The synonymy of An. sicaulti with An. labranchiae is confirmed. That An. labranchiae comprises the same species in these North African countries is important for malaria control.