Enterobius vermicularis (pinworm) infestation mimicking acute appendicitis in two children from Palestine: a case report.

BACKGROUND: Pinworm, Enterobius vermicularis, is a common parasitic illness, particularly among children in Palestine. On rare occasions, it can cause serious consequences such as acute appendicitis, which can still present a challenging diagnosis especially in children. CASE PRESENTATION: This report describes two cases (a 9 year old male and a 11 year old female, both Palestinian children from Hebron district) of acute appendicitis referred to Queen Alia Hebron Governmental Hospital in Palestine. The clinical examination revealed a lower abdominal pain, and they were diagnosed with appendicitis. The pathological examination after appendectomy showed the presence of eggs and pinworms. Anthelminthic medication was provided, and they were followed up for 6 weeks after the operation without any incidents. CONCLUSION: These cases highlight the importance of considering Enterobius vermicularis infestation in children with abdominal pain, as the parasites can mimic appendicitis. Prompt recognition and cautious laparoscopic appendectomy are crucial to prevent unnecessary surgery and peritoneal contamination, with the infestation being easily treatable with anthelmintic medication.

Molecular diagnosis of Taenia saginata from two patients in Palestine: two case reports.

BACKGROUND: Taeniasis, is a worldwide foodborne zoonotic disease caused by two principal species; Taenia saginata and Taenia solium. The tapeworm infects the intestine causing taeniasis in humans. Taeniasis is a very rare parasitic infection in Palestine with very few annual cases of unknown species. The infection rate and the disease status are not clear due to the lack of reports about the actual number of patients. CASE PRESENTATION: Two Palestinian patients; one male of 22 years old from Hebron and the other is female of 33 years old from Ramallah were referred to Palestinian Health Services in the West Bank, Palestine, complained of weight loss, abdominal pain and presence of motile segments of creamy color in the their stool. Microscopic analysis of the stool samples from infected cases revealed Taenia eggs and proglottids, confirmed taeniasis infection. The parasite species was identified as T. saginata by polymerase chain reaction (PCR) amplification and sequencing of the cytochrome oxidase -1 (COX-1) gene. CONCLUSION: Taeniasis is an unusual parasitic infection in Palestine, there is a growing concern that the actual numbers of infected individuals are much higher and the occurrence of human taeniasis is principally due to people's eating habits in consumption of raw or undercooked beef meat. This report highlighted for the first time the existence of taeniasis infection in the country; which necessitates the need to conduct further research and surveillance to reveal the actual infection rate and the available Taenia species.

First official report of bed bug (Hemiptera, Cimicidae) infestations in Algeria.

Background: Bed bugs are hematophagous insects with a long history of presence in human communities. Over the last three decades, infestations by bed bugs in human dwellings have drastically increased, leading to a rise in bed bug concerns. Nevertheless, very little is known about the bed bug species and their population diversity in Algeria. Method: A pilot entomological inventory was performed in May 2019 in Tizi Ouzou, in northern Algeria. The gathered bed bug specimens were identified by morphological and molecular approaches, followed by neighbor-joining and network phylogenetic analyses. Results: A total of seven out of 12 requested locations were allowed to inspect for bed bug infestation. Of these, three locations were found with active bed bug infestations. A total of 145 specimens belonging to different life stages [egg (21), nymph (74), adult male (17), and female (33)] were collected and analyzed using morphological and molecular approaches. The adult specimens were identified as Cimex lectularius according to specific morphological criteria, most importantly the pronotum laterally expanded with more flattened extreme margins. Morphological identification of the adults was confirmed further by conventional PCR targeting 450 bp fragment of the COI gene. All the nymphs and eggs were also molecularly identified as C. lectularius. Neighbor-Joining phylogenetic tree reconstructed with the collected specimens provides clues on the presence of two closely phylogenetic groups. The first one gathers our samples of Algeria with previously reported COI haplotype sequences from Asian, European, and North American countries. The second group encompasses a lesser-documented haplotype reported in Europe and Central America. These findings were further confirmed by network analysis. Conclusions: These results provide evidence of established C. lectularius infestation in Algeria and its potential dispersal capacity by travelers or immigrants and will help future management of these ectoparasites.

Population structure analysis of Phlebotomus papatasi populations using transcriptome microsatellites: possible implications for leishmaniasis control and vaccine development.

BACKGROUND: Phlebotomus papatasi is considered the primary vector of Leishmania major parasites that cause zoonotic cutaneous leishmaniasis (ZCL) in the Middle East and North Africa. Phlebotomus papatasi populations have been studied extensively, revealing the existence of different genetic populations and subpopulations over its large distribution range. Genetic diversity and population structure analysis using transcriptome microsatellite markers is important to uncover the vector distribution dynamics, essential for controlling ZCL in endemic areas. METHODS: In this study, we investigated the level of genetic variation using expressed sequence tag-derived simple sequence repeats (EST-SSRs) among field and colony P. papatasi samples collected from 25 different locations in 11 countries. A total of 302 P. papatasi sand fly individuals were analyzed, including at least 10 flies from each region. RESULTS: The analysis revealed a high-level population structure expressed by five distinct populations A through E, with moderate genetic differentiation among all populations. These genetic differences in expressed genes may enable P. papatasi to adapt to different environmental conditions along its distribution range and likely affect dispersal. CONCLUSIONS: Elucidating the population structuring of P. papatasi is essential to L. major containment efforts in endemic countries. Moreover, the level of genetic variation among these populations may improve our understanding of Leishmania-sand fly interactions and contribute to the efforts of vaccine development based on P. papatasi salivary proteins.

Molecular characterization and genetic diversity of Wolbachia endosymbionts in bed bugs (Hemiptera; Cimicidae) collected in Paris.

PURPOSE: This study aimed to investigate the genetic diversity of Wolbachia in field-caught bed bug species in Paris areas. METHODS: The bed bug specimens were captured from various infested localities in Paris and surrounding cities. They belonged to diverse life stages, including egg, nymph, and adult. They were then identified using morphological and molecular approaches. Furthermore, Wolbachia was detected, and its genetic diversity was investigated by conventional PCR of 16S-rRNA and Wolbachia surface protein (wsp) genes. RESULTS: A total of 256 bed bug specimens belonging to various life stages [adult (183 specimens), nymph (48), and egg (25)] were captured from seven private apartments, five social apartments, three houses, two immigrant residences, and one retirement home situated in 10 districts of Paris and 8 surrounding cities. They were identified as Cimex lectularius (237 specimens) and C. hemipterus (19) using morphological and molecular approaches. The presence and diversity of Wolbachia were ascertained by targeting 16S-rRNA and wsp genes. Based on molecular analysis, 182 and 148 out of 256 processed specimens were positive by amplifying 16S-rRNA and wsp fragments, respectively. The inferred phylogenetic analysis with 16S-rRNA and wsp sequences displayed monophyletic Wolbachia strains clustering each one in three populations. The median-joining network, including the Wolbachia 16S-rRNA and wsp sequences of C. lectularius and C. hemipterous specimens, indicated a significant genetic differentiation among these populations in Paris areas which was consent with Neighbor-Joining analyses. A phylogenetic analysis of our heterogenic Wolbachia sequences with those reported from other arthropod species confirmed their belonging to supergroup F. Moreover, no difference between Wolbachia sequences from eggs, nymphs, and adults belonging to the same clade and between Wolbachia sequences of C. lectularius and C. hemipterus were observed after sequence alignment. Furthermore, no significant correlation was found between multiple geographical locations (or accomodation type) where bed bugs were collected and the genetic diversity of Wolbachia. CONCLUSIONS: We highlight a significant heterogeneity within Wolbachia symbionts detected in C. lectularius and C. hemipterus. No correlation between Wolbachia species and bed bug species (C. lectularius versus C. hemipterus), physiological stages (egg, nymph, and adult), and sampling location was recorded in this study.

Genomic analysis of two phlebotomine sand fly vectors of Leishmania from the New and Old World.

Phlebotomine sand flies are of global significance as important vectors of human disease, transmitting bacterial, viral, and protozoan pathogens, including the kinetoplastid parasites of the genus Leishmania, the causative agents of devastating diseases collectively termed leishmaniasis. More than 40 pathogenic Leishmania species are transmitted to humans by approximately 35 sand fly species in 98 countries with hundreds of millions of people at risk around the world. No approved efficacious vaccine exists for leishmaniasis and available therapeutic drugs are either toxic and/or expensive, or the parasites are becoming resistant to the more recently developed drugs. Therefore, sand fly and/or reservoir control are currently the most effective strategies to break transmission. To better understand the biology of sand flies, including the mechanisms involved in their vectorial capacity, insecticide resistance, and population structures we sequenced the genomes of two geographically widespread and important sand fly vector species: Phlebotomus papatasi, a vector of Leishmania parasites that cause cutaneous leishmaniasis, (distributed in Europe, the Middle East and North Africa) and Lutzomyia longipalpis, a vector of Leishmania parasites that cause visceral leishmaniasis (distributed across Central and South America). We categorized and curated genes involved in processes important to their roles as disease vectors, including chemosensation, blood feeding, circadian rhythm, immunity, and detoxification, as well as mobile genetic elements. We also defined gene orthology and observed micro-synteny among the genomes. Finally, we present the genetic diversity and population structure of these species in their respective geographical areas. These genomes will be a foundation on which to base future efforts to prevent vector-borne transmission of Leishmania parasites.

Spatiotemporal analysis of cutaneous leishmaniasis in Palestine and foresight study by projections modelling until 2060 based on climate change prediction.

BACKGROUND: Cutaneous leishmaniasis (CL) is a vector-borne parasitic diseases of public health importance that is prevalent in the West Bank but not in the Gaza Strip. The disease caused by parasitic protozoans from the genus Leishmania and it is transmitted by infected phlebotomine sand flies. The aim of our study is to investigate the eco-epidemiological parameters and spatiotemporal projections of CL in Palestine over a 30-years period from 1990 through 2020 and to explore future projections until 2060. METHODOLOGY/PRINCIPAL FINDINGS: This long-term descriptive epidemiological study includes investigation of demographic characteristics of reported patients by the Palestinian Ministry of Health (PMoH). Moreover, we explored spatiotemporal distribution of CL including future projection based on climate change scenarios. The number of CL patients reported during this period was 5855 cases, and the average annual incidence rate (AAIR) was 18.5 cases/105 population. The male to female ratio was 1.25:1. Patients-age ranged from 2 months to 89 years (mean = 22.5, std 18.67, and the median was 18 years). More than 65% of the cases came from three governates in the West Bank; Jenin 29% (1617 cases), Jericho 25% (1403), and Tubas 12% (658) with no cases reported in the Gaza Strip. Seasonal occurrence of CL starts to increase in December and peaked during March and April of the following year. Current distribution of CL indicate that Jericho, Tubas, Jenin and Nablus have the most suitable climatic settings for the sandfly vectors. Future projections until 2060 suggest an increasing incidence from northwest of Jenin down to the southwest of Ramallah, disappearance of the foci in Jericho and Tubas throughout the Jordan Vally, and possible emergence of new foci in Gaza Strip. CONCLUSIONS/SIGNIFICANCE: The future projection of CL in Palestine until 2060 show a tendency of increasing incidence in the north western parts of the West Bank, disappearance from Jericho and Tubas throughout the Jordan Vally, and emergence of new CL endemic foci in the Gaza Strip. These results should be considered to implement effective control and surveillance systems to counteract spatial expansion of CL vectors.

Recent trends in human brucellosis in the West Bank, Palestine.

OBJECTIVES: To investigate the epidemiology of human brucellosis in the West Bank over the past 20 years, with a focus on recent trends in disease incidence from 2000 to 2020. METHODS: A long-term descriptive epidemiological study was conducted, based on the Palestinian Ministry of Health records from 2000 to 2020. RESULTS: The total number of cases was 7935 and the average annual incidence rate (AAIR) was 9.4 cases per 100 000 population. The AAIR ranged from 17.9 in 2000 to 15.7 cases per 100 000 population in 2020. The AAIR decreased markedly from 17.9 in 2000, to 2.9 cases per 100 000 population in 2012. A dramatic increase in cases started from 2013 onwards, reaching a peak in 2016. Higher incidence was reported in males (57.1%) and among the age group 11-20 years (29%). A higher number of cases was reported during April, May, and June. A total of 2850 patients (62.7%) reported contact with animals, and approximately 30% had at least one infected household member. CONCLUSIONS: The dramatic increase in human brucellosis in the West Bank was linked to the impaired control and surveillance of the disease. Mass vaccination, regular screenings, raising public health awareness, and monitoring of milk and homemade dairy products represent some recommended precautionary measures for coping with the epidemic.

Bed Bugs (Hemiptera: Cimicidae) Population Diversity and First Record of Cimex hemipterus in Paris.

Cimex lectularius and C. hemipterus are blood-sucking insects with a long history of presence in human communities. We investigated the molecular diversity of the bed bug population of Paris and its suburb cities using cytochrome oxidase 1 (CO1) sequencing. A total of 1211 specimens belonging to different life stages were collected from 62 infested human dwellings in Paris (13 out of 20 arrondissements) and the surrounding cities (18 cities). Morphological determination and COI sequencing of 132 specimens demonstrated C. lectularius as the predominant species and, surprisingly, the presence of C. hemipterus in four infested areas of Paris and its suburb cities. Neighbor-joining tree and network analyses depicted the presence of two C. lectularius populations. Most samples from Paris and its suburb cities clustered in a major clade. The second population encompasses specimens from Paris (arrondissements 11 and 19) and its suburb cities (e.g., Bobigny, Pantin, and Montreuil) that clustered with Hungary, Czechia, and Finland. This is the second evidence for C. hemipterus infestation in France and the third in Europe, which challenges the classic pattern of C. hemipterus dispersion and implies sympatric occurrence of C. lectularius and C. hemipterus. Since Paris is one of the most popular tourist destinations in the world, our observations shed light on bed bugs' dispersal dynamic and may help future vector control strategies.

HIV/AIDS in Palestine: A growing concern.

According to the United Nations AIDS reports in 2018, the Middle East and North Africa region is considered an area of increasing concern for HIV infection due to high mortality associated with AIDS. The incidence of HIV/AIDS in Palestine between 1988 and 2017 as reported by the Palestinian Ministry of Health was analyzed. A total of 98 cases were reported (79 AIDS patients and 19 HIV positives). A nationwide surveillance is needed to understand the epidemiology of HIV infection in the country. Identification of the HIV risk factors and health outreach directed to the public are essentially crucial prevention measures that should be implemented by the Palestinian Ministry of Health.

Epidemiology of Parasitic Infections in the West Bank and Gaza Strip, Palestine.

Parasitic infections are a public health problem that affects all population levels in developing countries including Palestine. The current study describes the epidemiology of parasitic infections in Palestine from 2008 to 2017. Twelve prominent parasitic infections were reported: leishmaniasis (both cutaneous and visceral), malaria, hydatid disease caused by hydatid cysts, toxoplasmosis, ascariasis, oxyuriasis, strongyloidiasis, taeniasis caused by Taenia saginata, amebiasis, giardiasis, and scabies. A total of 137,106 cases were reported; among them, 92,494 (67%) in the Gaza Strip and 44,612 (33%) in the West Bank. This study provides baseline information for better understanding the status of parasitic infections in Palestine and compares their epidemiology between the West Bank and Gaza Strip. Appropriate control measures and health education directed to the public about preventive measures should be considered to raise awareness about parasitic infections to lower their incidences and burden in Palestine.

Population Genetics of Phlebotomus papatasi from Endemic and Nonendemic Areas for Zoonotic Cutaneous Leishmaniasis in Morocco, as Revealed by Cytochrome Oxidase Gene Subunit I Sequencing.

Zoonotic cutaneous leishmaniasis (ZCL) caused by Leishmania major Yakimoff & Shokhor and transmitted by Phlebotomus papatasi (Scopoli) is a public health concern in Morocco. The disease is endemic mainly in pre-Saharan regions on the southern slope of the High Atlas Mountains. The northern slope of the High Atlas Mountains and the arid plains of central Morocco remain non-endemic and are currently considered high risk for ZCL. Here we investigate and compare the population genetic structure of P. papatasi populations sampled in various habitats in historical foci and non-endemic ZCL areas. A fragment of the mtDNA cytochrome oxidase I (CO1) gene was amplified and sequenced in 59 individuals from 10 P. papatasi populations. Haplotype diversity was probed, a median-joining network was generated (FST) and molecular variance (AMOVA) were analyzed. Overall, we identified 28 haplotypes with 32 distinct segregating sites, of which seven are parsimony informative. The rate of private haplotypes was high; 20 haplotypes (71.4%) are private ones and exclusive to a single population. The phylogenetic tree and the network reconstructed highlight a genetic structuration of these populations in two well defined groups: Ouarzazate (or endemic areas) and Non-Ouarzazate (or nonendemic areas). These groups are separated by the High Atlas Mountains. Overall, our study highlights differences in terms of population genetics between ZCL endemic and non-endemic areas. To what extent such differences would impact the transmission of L. major by natural P. papatasi population remains to be investigated.

Urogenital Myiasis Caused by Psychoda albipennis in a Female Child in Libya

Urogenital myiasis is a parasitic infestation caused by larvae of Psychoda spp. and it is very rare in humans. A 10- year old female was presented with urogenital myiasis and 4th stage Larvae of Psychoda albipennis (Diptera: Psychodidae) were found in urine. The patient was complained of painful sensation, discomfort and burning while urination. Urinary tract antiseptics were prescribed for the patient and advised to drink plenty of water for hydration. Local health authorities should take proper measures to maintain hygienic conditions for the people under risk.

Improving anti-trypanosomal activity of alkamides isolated from Achillea fragrantissima.

In previous studies the aerial parts of Achillea fragrantissima were found to have substantial antileishmanial and antitrypanosomal activity. A bioassay-guided fractionation of a dichloromethane extract yielded the isolation of the essential anti-trypanosomal compounds of the plant. Seven sesquiterpene lactones (including Achillolide-A), two flavonoids, chrysosplenol-D and chrysosplenetine, and four alkamides (including pellitorine) were identified. This is the first report for the isolation of the sesquiterpene lactones 3 and 4, chrysosplenetine and the group of alkamides from this plant. Bioevaluation against Trypanosoma brucei brucei TC221 (T.b brucei) using the Alamar-Blue assay revealed the novel alkamide 13 to have an IC50 value of 40.37µM. A compound library, derived from the alkamide pellitorine (10), was synthesized and bioevaluated in order to find even more active substances. The most active compounds 26 and 27 showed activities in submicromolar concentrations and selectivity indices of 20.1 and 45.6, respectively, towards macrophage cell line J774.1. Toxicity of 26 and 27 was assessed using the greater wax moth Galleria mellonella larvae as an in vivo model. No significant toxicity was observed for the concentration range of 1.25-20mM.

A pyoderma gangrenous-like cutaneous leishmaniasis in a Libyan woman with rheumatoid arthritis: a case report.

BACKGROUND: Several case reports describe diseases presenting with skin ulcerations, which resemble pyoderma gangrenosum especially in immune-compromised patients, often proven on further workup, to have an infective or malignant etiology. However, treatment of pyoderma gangrenosum by systemic steroids or other immunosuppressive agents may worsen the condition. CASE PRESENTATION: We report here, a 45 year-old Libyan woman with rheumatoid arthritis on low dose steroids with pyoderma gangrenosum-like skin lesions and positive pathergy. Slit-smear was positive for Leishmania amastigotes and histopathological examination confirmed the diagnosis of cutaneous leishmaniasis. The lesions healed completely by parenteral sodium stibogluconate (Pentostam) 600 mg daily. CONCLUSION: We report for the first time, a rare and unusual presentation of pyoderma gangrenosum like-cutaneous leishmaniasis in a patient with rheumatoid arthritis. Atypical cutaneous leishmaniasis should not be ruled out in the differential diagnosis of unresponsive skin diseases, with slit/smear and a skin biopsy is required.

Development of polymorphic EST microsatellite markers for the sand fly, Phlebotomus papatasi (Diptera: Psychodidae).

BACKGROUND: Phlebotomus papatasi is a widely distributed sand fly species in different tropical and sub-tropical regions including the Middle East and North Africa. It is considered an important vector that transmits Leishmania major parasites, the causative agents of cutaneous leishmaniasis. The development of microsatellite markers for this sand fly vector is of high interest to understand its population structure and to monitor its geographic dispersal. RESULTS: Fourteen polymorphic microsatellite markers were developed with simple di-, tri- and tetra-nucleotide repeats. The F statistics calculated for the 14 markers revealed high genetic diversity; expected heterozygosity (He) ranged from 0.407 to 0.767, while observed heterozygosity (Ho) was lower and ranged from 0.083 to 0.514. The number of alleles sampled fall in the range of 9-29. Three out of 14 markers deviated from Hardy-Weinberg expectations, no significant linkage disequilibrium was detected and high values for inbreeding coefficient (FIS) were likely due to inbreeding. CONCLUSIONS: The development of these functional microsatellites enable a high resolution of P. papatasi populations. It opens a path for researchers to perform multi locus-based population genetic structure analyses, and comparative mapping, a part of the efforts to uncover the population dynamics of this vector, which is an important global strategy for understanding the epidemiology and control of leishmaniasis.

Population genetics analysis of Phlebotomus papatasi sand flies from Egypt and Jordan based on mitochondrial cytochrome b haplotypes.

BACKGROUND: Phlebotomus papatasi sand flies are major vectors of Leishmania major and phlebovirus infection in North Africa and across the Middle East to the Indian subcontinent. Population genetics is a valuable tool in understanding the level of genetic variability present in vector populations, vector competence, and the development of novel control strategies. This study investigated the genetic differentiation between P. papatasi populations in Egypt and Jordan that inhabit distinct ecotopes and compared this structure to P. papatasi populations from a broader geographical range. METHODS: A 461 base pair (bp) fragment from the mtDNA cytochrome b (cyt b) gene was PCR amplified and sequenced from 116 individual female sand flies from Aswan and North Sinai, Egypt, as well as Swaimeh and Malka, Jordan. Haplotypes were identified and used to generate a median-joining network, F ST values and isolation-by-distance were also evaluated. Additional sand fly individuals from Afghanistan, Iran, Israel, Jordan, Libya, Tunisia and Turkey were included as well as previously published haplotypes to provide a geographically broad genetic variation analysis. RESULTS: Thirteen haplotypes displaying nine variant sites were identified from P. papatasi collected in Egypt and Jordan. No private haplotypes were identified from samples in North Sinai, Egypt, two were observed in Aswan, Egypt, four from Swaimeh, Jordan and two in Malka, Jordan. The Jordan populations clustered separately from the Egypt populations and produced more private haplotypes than those from Egypt. Pairwise F ST values fall in the range 0.024-0.648. CONCLUSION: The clustering patterns and pairwise F ST values indicate a strong differentiation between Egyptian and Jordanian populations, although this population structure is not due to isolation-by-distance. Other factors, such as environmental influences and the genetic variability in the circulating Le. major parasites, could possibly contribute to this heterogeneity. The present study aligns with previous reports in that pockets of genetic differentiation exists between populations of this widely dispersed species but, overall, the species remains relatively homogeneous.

Spatiotemporal and molecular epidemiology of cutaneous leishmaniasis in Libya.

BACKGROUND: Cutaneous leishmaniasis (CL) is a major public health problem in Libya. In this paper, we describe the eco-epidemiological parameters of CL during the armed conflict period from January 2011 till December 2012. Current spatiotemporal distributions of CL cases were explored and projected to the future using a correlative modelling approach. In addition the present results were compared with our previous data obtained for the time period 1995-2008. METHODOLOGY/PRINCIPAL FINDINGS: We investigated 312 CL patients who presented to the Dermatology Department at the Tripoli Central Hospital and came from 81 endemic areas distributed in 10 districts. The patients presented with typical localized lesions which appeared commonly on the face, arms and legs. Molecular identification of parasites by a PCR-RFLP approach targeting the ITS1 region of the rDNA was successful for 81 patients with two causative species identified: L. major and L. tropica comprised 59 (72.8%) and 22 (27.2%) cases, respectively. Around 77.3% of L. tropica CL and 57.7% of L. major CL caused single lesions. Five CL patients among our data set were seropositive for HIV. L. tropica was found mainly in three districts, Murqub (27.3%), Jabal al Gharbi (27.3%) and Misrata (13.7%) while L. major was found in two districts, in Jabal al Gharbi (61%) and Jafara (20.3%). Seasonal occurrence of CL cases showed that most cases (74.2%) admitted to the hospital between November and March, L. major cases from November till January (69.4%), and L. tropica cases mainly in January and February (41%). Two risk factors were identified for the two species; the presence of previously infected household members, and the presence of rodents and sandflies in patient's neighborhoods. Spatiotemporal projections using correlative distribution models based on current case data and climatic conditions showed that coastal regions have a higher level of risk due to more favourable conditions for the transmitting vectors. CONCLUSION: Future projection of CL until 2060 showed a trend of increasing incidence of CL in the north-western part of Libya, a spread along the coastal region and a possible emergence of new endemics in the north-eastern districts of Libya. These results should be considered for control programs to prevent the emergence of new endemic areas taking also into consideration changes in socio-economical factors such as migration, conflicts, urbanization, land use and access to health care.

Microsatellite analysis reveals genetic structure of Leishmania tropica.

The current rapid spread of leishmaniases caused by Leishmania tropica and the complexity of its clinical spectrum call for this parasite's epidemiological and evolutionary investigation. Evaluation of its population structure by isoenzyme electrophoresis and previous molecular biological analysis has proved difficult. In this study, we used 21 microsatellite loci to type 117 strains from different African and Asian locations. Eighty-one different genotypes were found. A genetic bottleneck supported by a gradient in the number of alleles and consistent with the geographical structure of the Middle East suggests an African origin of this species. A Bayesian approach identified 10 genetic clusters that correlated predominantly with geographical origin. The strains in the 'Asia' cluster form a very heterogeneous sub-population, with a varied but inter-related genotype that is geographically very widely dispersed and consistent with anthroponotic transmission of the parasite. The other nine clusters were more homogenous. The propagation of L. tropica appears to be predominantly clonal. In Africa and the Middle East, anthroponotic and zoonotic systems of distribution may contribute to the development of overlapping, genetically distinct populations of L. tropica.