Multilocus microsatellite typing (MLMT) of strains from Turkey and Cyprus reveals a novel monophyletic L. donovani sensu lato group

Background

New foci of human CL caused by strains of the Leishmania donovani (L. donovani) complex have been recently described in Cyprus and the Çukurova region in Turkey (L. infantum) situated 150 km north of Cyprus. Cypriot strains were typed by Multilocus Enzyme Electrophoresis (MLEE) using the Montpellier (MON) system as L. donovani zymodeme MON-37. However, multilocus microsatellite typing (MLMT) has shown that this zymodeme is paraphyletic; composed of distantly related genetic subgroups of different geographical origin. Consequently the origin of the Cypriot strains remained enigmatic.

Methodology/Principal Findings

The Cypriot strains were compared with a set of Turkish isolates obtained from a CL patient and sand fly vectors in south-east Turkey (Çukurova region; CUK strains) and from a VL patient in the south-west (Kuşadasi; EP59 strain). These Turkish strains were initially analyzed using the K26-PCR assay that discriminates MON-1 strains by their amplicon size. In line with previous DNA-based data, the strains were inferred to the L. donovani complex and characterized as non MON-1. For these strains MLEE typing revealed two novel zymodemes; L. donovani MON-309 (CUK strains) and MON-308 (EP59). A population genetic analysis of the Turkish isolates was performed using 14 hyper-variable microsatellite loci. The genotypic profiles of 68 previously analyzed L. donovani complex strains from major endemic regions were included for comparison. Population structures were inferred by combination of Bayesian model-based and distance-based approaches. MLMT placed the Turkish and Cypriot strains in a subclade of a newly discovered, genetically distinct L. infantum monophyletic group, suggesting that the Cypriot strains may originate from Turkey.

Conclusion

The discovery of a genetically distinct L. infantum monophyletic group in the south-eastern Mediterranean stresses the importance of species genetic characterization towards better understanding, monitoring and controlling the spread of leishmaniasis in this region.     

Sand fly (Diptera: Psychodidae) distribution in the endemic and non‐endemic foci of visceral leishmaniasis in northwestern Iran

An entomological study was conducted from June to September, 2010 in rural regions of Azarbayjan‐e‐sharqi, Azarbayjan‐e‐qarbi, and Ardabil provinces in northwestern Iran to determine sand fly fauna, diversity, and distribution in different habitats and altitudes using both sticky papers and light traps. Geographical distribution of sand flies and the similarity of populations in different locations were analyzed ecologically based on the Shannon‐Wiener Index and Jacard Coefficient, respectively. A total of 3,982 specimens was collected and sixteen species recorded. They belonged to the genera Phlebotomus [subgenus Phlebotomus (P. papatasi), Paraphlebotomus (P. sergenti, P. mongolensis, P. caucasicus, P. jacusieli), Larroussius (P. major s.l., P. tobbi, P. perfiliewi transcaucasicus, P. kandelakii) and Adlerius (P. halepensis, P. brevis, P. longiductus, P. balcanicus)], and Sergentomyia [subgenus Sergentomyia (S. sintoni, S. dentata and S. theodori)]. P. papatasi was the predominant species in all the locations except Bileh Savar, Macu, and Meshkin Shahr, followed by P. perfiliewi transcaucasicus and P. kandelakii. The latter species were caught from different habitats and altitudes with higher frequency than other species of the subgenus Larroussius. The lowest abundance belonged to P. jacusieli. The predominant species of subgenus Adlerius was P. halepensis. Data analysis showed that Meshkin Shahr and Bileh Savar had high and low diversities of sand fly distribution, respectively. Meshkin Shahr and Sarab districts had the highest similarity. Both are located in the foothills of Sabalan Mountain, with high diversity and richness.     

Morphometric and morphological variation between two different populations of Phlebotomus major s.l. from endemic and non‐endemic foci of visceral leishmaniasis in Iran

Populations of Phlebotomus major were examined in two endemic and nonendemic foci of visceral leishmaniasis in Iran. Based on the shape of the aedeagus and ventrally located hairs of coxite and pharyngeal armatures, two morphotypes were found sympatrically in the endemic area of Borazjan. Significant differences in morphometric survey were observed in at least 11 measured characters. The aedeagus of the non‐endemic Miyandoab morphotype, and also of a few specimens from Borazjan, is completely parallel throughout its length with a slightly expanded end. Ventrally located hairs of the middle coxite were longer and more compact. It is close morphologically to P. major neglectus (P. neglectus), which was recently recorded from Iran. It is also morphologically similar to P. notus, which has not yet been reported from Iran and needs further investigation. The aedeagus of the morphotype occurring only in Borazjan is narrower in the middle and the hairs are closer to the base of the coxite and are shorter and more outspread, which makes it similar to P. major krimensis or P. neglectus. The two morphotypes occurring sympatrically in Borazjan do not appear to be subspecies and it may be premature to propose them as separate species. Further investigation is needed to clarify the actual status of P. major s. l. in Iran.     

Genetic variation within and among populations of the narrow endemic,delphinium viridescens (Ranunculaceae)

Delphinium viridescens Leiberg (Ranunculaceae) is a narrow endemic, known from only 17 populations in the Wenatchee Mountains of central Washington. Electrophoretic data for ten loci and approximately 50 plants from each of the 17 populations indicate high levels of variability both within and among populations. High levels of heterozygosity, coupled with a general conformance of genotype frequencies to Hardy-Weinberg expectations, suggest that D. viridescens is an outcrossing species, and outcrossing rates range from 0.391 to 1.454. Although all populations share a suite of common alleles, interpopulational differences in allele frequency were detected. Nei's genetic identities range from 0.883 to 1.000, with a mean of 0.964, suggesting only slight differentiation among populations and at least moderate levels of interpopulational gene flow. However, F_ST values indicate greater interpopulational heterogeneity. The data from this study are intended for use in developing a management plan for D. viridescens, to maintain the viability of this species, and to assess the need for its listing as threatened or endangered.     

Multilocus sequence typing system (MLST) reveals a significant association of Entamoeba histolytica genetic patterns with disease outcome

The relationship between parasite genotypes and outcome of amoebic infection is still a paradox and needed to be explored. Proper identification and genetic characterization of Entamoeba histolytica clinical isolates is an effective tool for exploring this relation. Along with conventional polymorphic marker (Chitinase), tRNA linked short tandem repeat (STR) loci has been employed as multilocus genotyping tool due to its better resolution and evolutionary significance. Some common as well as exclusive repeat patterns showing significant relation with disease outcome have been identified. Phylogenetic analysis revealed that repeat patterns exclusively found in asymptomatic and amoebic liver abscess derived isolates are placed in a common lineage and has similar association pattern with the disease outcome. Assumption can be made that isolates of E. histolytica remaining asymptomatic is genetically closer siblings of those causing liver abscess rather than the diarrheal isolates.     

Microsatellite analysis reveals genetically distinct populations of red pine (Pinus resinosa, Pinaceae)

Red pine (Pinus resinosa Ait.) is an ecologically and economically important forest tree species of northeastern North America and is considered one of the most genetically depauperate conifer species in the region. We have isolated and characterized 13 nuclear microsatellite loci by screening a partial genomic library with di-, tri-, and tetranucleotide repeat oligonucleotide probes. In an analysis of over 500 individuals representing 17 red pine populations from Manitoba through Newfoundland, five polymorphic microsatellite loci with an average of nine alleles per locus were identified. The mean expected and observed heterozygosity values were 0.508 and 0.185, respectively. Significant departures from Hardy-Weinberg equilibrium with excess homozygosity indicating high levels of inbreeding were evident in all populations studied. The population differentiation was high with 28-35% of genetic variation partitioned among populations. The genetic distance analysis showed that three northeastern (two Newfoundland and one New Brunswick) populations are genetically distinct from the remaining populations. The coalescence-based analysis suggests that "northeastern" and "main" populations likely became isolated during the most recent Pleistocene glacial period, and severe population bottlenecks may have led to the evolution of a highly selfing mating system in red pine.     

Comparative microsatellite typing of new world leishmania infantum reveals low heterogeneity among populations and its recent old world origin

Leishmania infantum (syn. L. chagasi) is the causative agent of visceral leishmaniasis (VL) in the New World (NW) with endemic regions extending from southern USA to northern Argentina. The two hypotheses about the origin of VL in the NW suggest (1) recent importation of L. infantum from the Old World (OW), or (2) an indigenous origin and a distinct taxonomic rank for the NW parasite. Multilocus microsatellite typing was applied in a survey of 98 L. infantum isolates from different NW foci. The microsatellite profiles obtained were compared to those of 308 L. infantum and 20 L. donovani strains from OW countries previously assigned to well-defined populations. Two main populations were identified for both NW and OW L. infantum. Most of the NW strains belonged to population 1, which corresponded to the OW MON-1 population. However, the NW population was much more homogeneous. A second, more heterogeneous, population comprised most Caribbean strains and corresponded to the OW non-MON-1 population. All Brazilian L. infantum strains belonged to population 1, although they represented 61% of the sample and originated from 9 states. Population analysis including the OW L. infantum populations indicated that the NW strains were more similar to MON-1 and non-MON-1 sub-populations of L. infantum from southwest Europe, than to any other OW sub-population. Moreover, similarity between NW and Southwest European L. infantum was higher than between OW L. infantum from distinct parts of the Mediterranean region, Middle East and Central Asia. No correlation was found between NW L. infantum genotypes and clinical picture or host background. This study represents the first continent-wide analysis of NW L. infantum population structure. It confirmed that the agent of VL in the NW is L. infantum and that the parasite has been recently imported multiple times to the NW from southwest Europe.     

Allozyme variation within and between populations inLolium (Poaceae)

Isozyme analysis was used to determine genetic variation within and between populations of sevenLolium species. All populations from the inbreeding species (L. temulentum, L. remotum, L. loliaceum, andL. persicum) were completely fixed for all enzymes scored. They also contained, for four of the five enzyme systems studied, exactly the same allelic variant. The three cross-breeding species showed large within-population variation and much less between-population variation. The great similarity of the allozymic variants found in all species, made the division of the genusLolium into species on basis of allozymic data difficult. It was not possible to separate the different inbreeding species from each other. Within the cross-breeding groupL. multiflorum andL. rigidum could be distinguished fromL. perenne. L. multiflorum, andL. rigidum could, with more difficulty, also be separated from each other. Allelic variation could have more relation with the provenance of the populations than with taxonomic classification.Genetic variation inLolium spp. II. For first part see Pl. Syst. Evol. 188: 87–99.     

Multilocus phylogeny and systematics of Iberian endemic Squalius (Actinopterygii,Leuciscidae)

Inferring the evolutionary history of a group of species can be challenging given the many factors involved. In recent years, the increased availability of sequences of multiple genes per species has spurred the development of new methodologies to analyse multilocus data sets. Two approaches that analyse such data are concatenated supermatrix and coalescent-based species-tree analyses. In this study, we used both of these methods to infer the phylogenetic relationships of Iberian species of the genus Squalius from one mitochondrial and six nuclear genes. We found mitonuclear discordance in the phylogenetic relationships of the group. According to the mitochondrial gene analysis, all species were recovered as monophyletic except S. pyrenaicus; besides, in the concatenated supermatrix analysis of the nuclear markers, this species resolved as polyphyletic with three divergent evolutionary lineages. The coalescent-based nuclear species-tree analysis rendered a well-resolved phylogeny compared with the supermatrix analysis, which was unable to discern between S. carolitertii, S. castellanus and one of the evolutionary lineages of S. pyrenaicus. This result is likely due to the better integration of population uncertainty in the coalescent approach. Furthermore, Bayesian multilocus species delimitation analyses based on a BPP approach strongly supported the distinct nuclear lineages as different species. Nevertheless, the supermatrix analysis was able to obtain well-supported relationships in the divergent lineages with low numbers of individuals. Our study highlights the usefulness of different analytical methodologies to obtain a more complete picture of the evolutionary history of taxa, especially when discordant patterns among genes are found.     

Insecticide susceptibility of Phlebotomus argentipes in visceral leishmaniasis endemic districts in India and Nepal

Objectives

To investigate the DDT and deltamethrin susceptibility of Phlebotomus argentipes, the vector of Leishmania donovani, responsible for visceral leishmaniasis (VL), in two countries (India and Nepal) with different histories of insecticide exposure.

Methods

Standard WHO testing procedures were applied using 4% DDT and 0.05% deltamethrin impregnated papers. The effect of the physiological status (fed and unfed) of females on the outcome of the bioassays was assessed and the optimal time of exposure for deltamethrin was evaluated on a colony population. Field populations from both countries were tested.

Results

Fed and unfed females responded in a similar way. For exposure time on field samples 60 min was adopted for both DDT and deltamethrin. In Bihar, knockdown and mortality with DDT was respectively 20 and 43%. In Nepal almost all sand flies were killed, except at the border with Bihar (mortality 62%). With 0.05% deltamethrin, between 96 and 100% of the sand flies were killed in both regions.

Conclusions

Based on literature and present data 4% DDT and 0.05% deltamethrin seem to be acceptable discriminating concentrations to separate resistant from susceptible populations. Resistance to DDT was confirmed in Bihar and in a border village of Nepal, but the sand flies were still susceptible in villages more inside Nepal where only synthetic pyrethroids are used for indoor spraying. The low effectiveness of indoor spraying with DDT in Bihar to control VL can be partially explained by this resistance hence other classes of insecticides should be tested. In both countries P. argentipes sand flies were susceptible to deltamethrin.     

Genetic diversity and differentiation of masu salmon (Oncorhynchus masou masou) between and within cultured populations inferred from microsatellite DNA analysis

Masu salmon, Oncorhynchus masou masou, is one of the most valuable fishery species that has been introduced to China, though to date no studies on the genetic diversity and genetic relationship among hatchery populations has been performed with molecular markers. We undertook such a study and sampled 120 individuals from three hatchery stocks and analyzed 20 microsatellite loci. All loci were polymorphic and a total of 91 alleles were detected. A relatively low level of genetic diversity was revealed with effective number of allele of 3.1094, 3.3299 and 3.1894 and expected heterozygosity of 0.6600, 0.6648 and 0.6638 in the three stocks, respectively. Deviations from Hardy-Weinberg equilibrium were found due to heterozygote deficit. Accordingly, evidence of genetic bottlenecks were found in the three stocks. An individual assignment test demonstrated that 85% of individuals were correctly assigned into their original stocks. Pairwise Fst revealed that significant differentiation occurred between these three stocks. The results of the study indicated that disequilibrium of genetic structure and differentiation has occurred in all three stocks. This information collectively provides a basis for measures to avoid of loss of genetic diversity and introgression in Chinese aquaculture.     

Genetic diversity and differentiation of masu salmon (Oncorhynchus masou masou) between and within cultured populations inferred from microsatellite DNA analysis

Masu salmon,Oncorhynchus masou masou,is one of the most valuable fishery species that has been introduced to China,though to date no studies on the genetic diversity and genetic relationship among hatchery populations has been performed with molecular markers.We undertook such a study and sampled 120 individuals from three hatchery stocks and analyzed 20 microsatellite loci.All loci were polymorphic and a total of 91 alleles were detected.A relatively low level of genetic diversity was revealed with effective number of allele of 3.1094,3.3299 and 3.1894 and expected heterozygosity of 0.6600,0.6648 and 0.6638 in the three stocks,respectively.Deviations from Hardy-Weinberg equilibrium were found due to heterozygote deficit.Accordingly,evidence of genetic bottlenecks were found in the three stocks.An individual assignment test demonstrated that 85% of individuals were correctly assigned into their original stocks.Pairwise Fst revealed that significant differentiation occurred between these three stocks.The results of the study indicated that disequilibrium of genetic structure and differentiation has occurred in all three stocks.This information collectively provides a basis for measures to avoid of loss of genetic diversity and introgression in Chinese aquaculture.     

Molecular characterization and toxigenic profile of Aspergillus section Nigri populations isolated from the main grape-growing regions in Argentina

Aims: The objective of this study was to evaluate the biodiversity of Aspergillus section Nigri populations from Argentinean vineyards by morphological, toxigenic and AFLP analysis. Materials and methods: Five hundred and thirty‐eight strains were isolated from grapes during 2006/07 and 2007/08 vintages. The morphological identification and toxigenic profile for all strains isolated were performed. Eighty‐eight strains were selected for characterization at species level by AFLP markers. Cluster analysis showed a clear separation into four main groups: A. carbonarius, A. tubingensis, A. niger‘aggregate’ and Aspergillus‘uniseriate’. A. carbonarius strains constituted a homogeneous group, while a high degree of genetic diversity was found within the A. niger‘aggregate’ and ‘A. uniseriate’ clusters. The A. tubingensis cluster was the most prevalent group and was clearly separated from A. niger‘aggregate’. Ten strains showed 45% homology with A. tubingensis FRR 5720 ex‐type strain and were considered as ‘atypical’ or a closely related species. AFLP results indicate that no genotypical differences can be established between ochratoxigenic and nonochratoxigenic strains. Conclusions: Aspergillus section Nigri populations on grapes were represented mainly by four groups. A. tubingensis species were separated from A. niger‘aggregate’ group and some of their strains produced OTA. Significance and Impact of the Study: This study provides new data on molecular characterization of Aspergillus section Nigri populations in Argentina.     

Multilocus sequence typing supports the hypothesis that cow- and human-associated Salmonella isolates represent distinct and overlapping populations

A collection of 179 human and 156 bovine clinical Salmonella isolates obtained from across New York state over the course of 1 year was characterized using serotyping and a multilocus sequence typing (MLST) scheme based on the sequencing of three genes (fimA, manB, and mdh). The 335 isolates were differentiated into 52 serotypes and 72 sequence types (STs). Analyses of bovine isolates collected on different farms over time indicated that specific subtypes can persist over time on a given farm; in particular, a number of farms showed evidence for the persistence of a specific Salmonella enterica serotype Newport sequence type. Serotypes and STs were not randomly distributed among human and bovine isolates, and selected serotypes and STs were associated exclusively with either human or bovine sources. A number of common STs were geographically widespread. For example, ST6, which includes isolates representing serotype Typhimurium as well as the emerging serotype 4,5,12:i:-, was found among human and bovine isolates in a number of counties in New York state. Phylogenetic analyses supported the possibility that serotype 4,5,12:i:- is closely related to Salmonella serotype Typhimurium. Salmonella serotype Newport was found to represent two distinct evolutionary lineages that differ in their frequencies among human and bovine isolates. A number of Salmonella isolates carried two copies of manB (33 isolates) or showed small deletion events in fimA (nine isolates); these duplication and deletion events may provide mechanisms for the rapid diversification of Salmonella surface molecules. We conclude that the combined use of an economical three-gene MLST scheme and serotyping can provide considerable new insights into the evolution and transmission of Salmonella.     

Multilocus sequence typing (MLST) for the infra-generic taxonomic classification of entomopathogenic Rickettsiella bacteria

The genus Rickettsiella comprises intracellular bacterial pathogens of a wide range of arthropods that are currently classified in four recognized species and numerous further pathotypes. However, both the delineation of and the synonymization of pathotypes with species are highly problematic. In the sequel of a previous phylogenomic study at the supra-generic level, nine selected genes - the 16S and 23S rRNA genes and the protein-encoding genes dnaG, ftsY, gidA, ksgA, rpoB, rpsA, and sucB - were evaluated for their potential as markers for the generic and infra-generic taxonomic classification of Rickettsiella-like bacteria. A methodological approach combining phylogenetic reconstruction with likelihood-based significance testing was employed on the basis of sequence data from the species Rickettsiella grylli and Rickettsiella popilliae, pathotypes 'Rickettsiella melolonthae' and 'Rickettsiella tipulae'. This study provides the first multilocus sequence typing (MLST) data for the genus Rickettsiella and identifies two new genetic markers, gidA and sucB, for the infra-generic classification within this taxon. In particular, aforesaid genes were found more reliable and informative markers than the corresponding 16S rRNA-encoding sequences that failed to produce strictly significant infra-generic taxonomic assignments. However, gidA- and sucB-based phylogenies were consistent with the currently accepted view of species delineation and species-pathotype synonymization within the genus Rickettsiella.     

Multilocus microsatellite typing revealed high genetic variability of Leishmania donovani strains isolated during and after a Kala-azar epidemic in Libo Kemkem district, northwest Ethiopia

In 2004, an outbreak of kala-azar (KA) occurred for the first time in Libo Kemkem district, in the highland area of northwest Ethiopia. In order to track the possible origins of the outbreak parasites, we have investigated 19 strains of Leishmania donovani that were collected during (n = 6) and after (n = 13) the outbreak by using 14 highly polymorphic microsatellite markers. Unique microsatellite profiles were obtained for all strains from Libo Kemkem. When compared to those of L. donovani strains from different Ethiopian, Kenyan and Sudanese foci, by genetic distance and Bayesian clustering model analyses, most strains from Libo Kemkem grouped with strains from: (i) Humera and Metema in the lowlands and Belessa in the highland of Ethiopia, and (ii) Sudan, at different hierarchal levels. The strains from Libo Kemkem district were assigned at least to three genetically distinct clusters (A, B1 and B2) of which only one, cluster B2, consisted exclusively of strains from Libo Kemkem. The fact that most of the outbreak strains were found to be related to strains from well-known KA foci in northwest Ethiopia and Sudan might suggest multiple introductions of L. donovani strains from these foci into Libo Kemkem district.     

Multilocus coalescent analysis of haemoglobin differentiation between low- and high-altitude populations of crested ducks (Lophonetta specularioides)

Hypoxia is a key factor determining survival, and haemoglobins are targets of selection in species native to high-altitude regions. We studied population genetic structure and evaluated evidence for local adaptation in the crested duck (Lophonetta specularioides). Differentiation, gene flow and time since divergence between highland and lowland populations were assessed for three haemoglobin genes (α(A) , α(D) , β(A) ) and compared to seven reference loci (six autosomal introns and mtDNA). Four derived amino acid replacements were found in the globin genes that had elevated Φ(ST) values between the Andean highlands and Patagonian lowlands. A single β(A) -globin polymorphism at a site known to influence O(2) affinity was fixed for different alleles in the two populations, whereas three α(A) - and α(D) -globin polymorphisms exhibited high heterozygosity in the highlands but not in the lowlands. Coalescent analyses supported restricted gene flow for haemoglobin alleles and mitochondrial DNA but nonzero gene flow for the introns. Simulating genetic data under a drift-migration model of selective neutrality, the β(A) -globin fell outside the 95% confidence limit of simulated data, suggesting that directional selection is maintaining different variants in the contrasting elevational environments, thereby restricting migration of β(A) -globin alleles. The α(A) - and α(D) -globins, by contrast, did not differ from the simulated values, suggesting that variants in these genes are either selectively neutral, or that the effects of selection could not be differentiated from background levels of population structure and linkage disequilibrium. This study illustrates the combined effects of selection and population history on inferring levels of population divergence for a species distributed across an altitudinal gradient in which selection for hypoxia resistance has likely played an important role.     

Coeficient of relationship (RI) within and between four black venezuelan populations

The coefficient of relationship by isonymy R_i was obteined using paternal and maternal surnames of individuals in four black Venezuelan populations. The analysis of eight R_i values obtained from different combinations of surnames within each population and between population in two periods of time (1900–1920 and 1944–1967) show that: 1) Higher values of R_i are those that include combinations of maternal surnames, 2) R_i values of the second period are higher than those shown in the first, 3) No correlation was observed between R_i values and geographic distance. These results indicate that there is a tendency towards matrilocal behavior and show agreement with the degree of isolation of each population. The use of four surnames for estimating the coefficient of relationship by isonymy R_i, permits better comparisons of the relationship between and within groups and gives detailed information of the population structure.     

Genetic diversity and differentiation of the Korean starry flounder (Platichthys stellatus) between and within cultured stocks and wild populations inferred from microsatellite DNA analysis

The Korean starry flounder, Platichthys stellatus, is economically valuable coastal resident fish species. However, the annual catch of this fish has fluctuated and suffered major declines in Korea. We examined the genetic diversity and population structure for four wild populations and three hatchery stocks of Korean starry flounder to protect its genetic integrity using nine microsatellites. A group of 339 genotypes belonging to seven populations were screened. High degrees of polymorphism at the microsatellite loci were observed within both the wild and hatchery populations. Compared to the wild populations, genetic changes, including reduced genetic diversity and highly significant differentiation, have occurred in cultured stocks. Significant population differentiation was also observed in wild starry flounder populations. Similar degrees of inbreeding and significant Hardy–Weinberg equilibrium deviations were detected in both the wild and the hatchery populations. The genetic connectivity pattern identified four distinct metapopulations of starry flounder in Korea by clustering in the phylogenetic tree, Bayesian analyses, molecular variance analysis, PCA and multidimensional scaling analysis. A pattern of isolation-by-distance was not significant. This genetic differentiation may be the result of the co-effects of various factors, such as historic dispersal, local environment or anthropogenic activities. These results provide useful information for the genetic monitoring of P. stellatus hatchery stocks, for the genetic improvement of this species by selective breeding and for designing suitable management guidelines for the conservation of this species.     

Distribution of phlebotomine fauna (Diptera: Psychodidae) across an urban-rural gradient in an area of endemic visceral leishmaniasis in northern Brazil

The number of visceral leishmaniasis (VL) cases has increased over the past 10 years in Brazil, especially in the North and Northeast regions of the country. The aim of this study was to evaluate the urbanisation of VL vectors in Barcarena, Pará, an area in northern Brazil where VL is endemic. Sandflies were captured using Centers for Disease Control (CDC) light traps along an urban-rural gradient. The CDC traps were installed inside hen houses at a height of 150 cm. A total of 5,089 sandflies were collected and 11 species were identified. The predominant species was Lutzomyia longipalpis (rate of 95.15%), which suggests its participation in the transmission of VL. A total of 1,451 Lu. longipalpis females were dissected and no Leishmania infections were detected. Most of the sandflies were captured at the border of a forest (88.25%) and no flies were captured in the urban area, which suggests that transmission is still restricted to rural sites. However, the fact that a specimen was collected in an intermediate area indicates that urbanisation is a real possibility and that vector monitoring is important.