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Prior to 1999, Ghana was not known to be a Cutaneous Leishmaniasis (CL) endemic country. The outbreak of CL in the Volta Region in 1999 resulted in the need for urgent investigations to understand the disease transmission dynamics. Monthly entomological collections from January 2006 to May 2007 revealed 99.8% (21,980/22,016) of sand flies collected were Sergentomyia and 0.2% (36/22,016) Phlebotomus, the putative vector of CL in the Old World. The density of Phlebotomus was so low, their vectorial role is uncertain. This study was therefore aimed at determining the possible vector species in the outbreak area. We collected sand flies from homes to examine anthropophily, by testing their blood meals. The blood-meal sources of 275 (20.5%) of 1342 collected female sand flies revealed the highest proportion of animal blood source was chicken (33.8%) and goat (12.4%). Humans accounted for 32% of blood meal sources. Identified species included: Sergentomyia africana africana (26.9%), S. ingrami (34.5%) and S. simillima (38.2%), which were found to have single and mixed blood-meals, with S. simillima having the highest proportion that contained human blood (14.6%). Using molecular methods, we examined unfed flies and flies found anthropophilic for the presence of Leishmania major DNA. Poolscreening analysis revealed 3 pools of S. ingrami positive with L. major DNA, with an infection rate of 1.27% (95% confidence interval: 2.467–3.647). This study showed that some Sergentomyia species are anthropophilic, contain L. major DNA, and could be involved in the transmission of CL in Ghana. There is however the need to conclusively validate the role of S. ingrami as a vector of L. major in Ghana, by isolating the parasite and initiating experimental transmission studies.

Post-harvest losses due to insect pest infestation in storage constitute a challenge to sustainable food security and economic losses to farmers throughout the world. Use of synthetic chemicals have been the most effective means of reducing losses in storage. Unfortunately, these toxicants have adverse effects in humans and the environment. There is renewed search for safer plant products as alternatives. In this study, we assessed the potential use of Piper guineense seed oil in the control of cowpea bruchid, Callosobruchus maculatus (F.) infestation on stored cowpea seeds. Adult mortality, oviposition rate, F1 progeny emergence, cowpea seed damage and seed germinability were the indices considered in the assessment under laboratory conditions. The setup of the experiment was completely randomized design (CRD). Statistical analysis of the data was by analysis of variance (ANOVA). Adult C. maculatus mortality was dose-dependent with higher dosages inducing 100% mortality. The number of eggs laid on the treated seeds were significantly (P

Background: Bed bugs belong systematically to Order Hemiptera; Suborder Heteroptera; Family Cimicidae are of public health importance as ectoparasites of mammals and birds, however, only a few species are the putative ectoparasites of humans. Bed bugs are a wingless bloodsucking hemipterous bug (Cimex spp.) sometimes infesting houses and especially beds and feeding on human blood. Correct species identification is very important in order to design targeted strategies for surveillance and control of bed bugs in a given area. Methods: Adult bed bugs were collected from houses located in the southwest of Iran. The specimens were morphologically identified to the species level and then confirmed using molecular methods. Results: The mtDNA 16S rRNA sequences obtained from the specimens, and phylogenetic tree derived, showed that all the sequences belong to Cimex hemipterus. The Disparity Index among results showed that all the specimens were of a heterogeneous population. To the best of our knowledge, the leg structure of this species has not previously been documented and this is the first report of an open-closed rack system in the legs of C. hemipterus.Conclusions: Previous studies claimed that C. lectularius is the abundant species of Cimicids in Iran. But this investigation showed that C. hemipterus is the prevalent species in the southwest of Iran.

Leishmaniasis, caused by protozoan parasites of the Leishmania genus, represents an important health problem in many regions of the world. Lack of effective point-of-care (POC) diagnostic tests applicable in resources-limited endemic areas is a critical barrier to effective treatment and control of leishmaniasis. The development of the loop-mediated isothermal amplification (LAMP) assay has provided a new tool towards the development of a POC diagnostic test based on the amplification of pathogen DNA. LAMP does not require a thermocycler, is relatively inexpensive, and is simple to perform with high amplification sensitivity and specificity. In this review, we discuss the current technical developments, applications, diagnostic performance, challenges, and future of LAMP for molecular diagnosis and surveillance of Leishmania parasites. Studies employing the LAMP assay to diagnose human leishmaniasis have reported sensitivities of 80% to 100% and specificities of 94% to 100%. These observations suggest that LAMP offers a good molecular POC technique for the diagnosis of leishmaniasis and is also readily applicable to screening at-risk populations and vector sand flies for Leishmania infection in endemic areas., Author summary Developing sensitive point-of-care diagnostic tests is vital for enhancing Leishmania-infection control programs and treatment. This review provides information on the development of the loop-mediated isothermal amplification (LAMP) diagnostic test and highlights recent advances in the field of molecular diagnosis of leishmaniasis and the needs for future research. Furthermore, we elaborate of the future potential of LAMP as a rapid point-of-care (in-clinic and in the field) test for diagnosis and entomological monitoring of Leishmania infection, including evaluation of control programs in Leishmania-endemic areas.

Hybrid genotypes have been repeatedly described among natural isolates of Leishmania, and the recovery of experimental hybrids from sand flies co-infected with different strains or species of Leishmania has formally demonstrated that members of the genus possess the machinery for genetic exchange. As neither gamete stages nor cell fusion events have been directly observed during parasite development in the vector, we have relied on a classical genetic analysis to determine if Leishmania has a true sexual cycle. Here, we used whole genome sequencing to follow the chromosomal inheritance patterns of experimental hybrids generated within and between different strains of L. major and L. infantum. We also generated and sequenced the first experimental hybrids in L. tropica. We found that in each case the parental somy and allele contributions matched the inheritance patterns expected under meiosis 97–99% of the time. The hybrids were equivalent to F1 progeny, heterozygous throughout most of the genome for the markers that were homozygous and different between the parents. Rare, non-Mendelian patterns of chromosomal inheritance were observed, including a gain or loss of somy, and loss of heterozygosity, that likely arose during meiosis or during mitotic divisions of the progeny clones in the fly or culture. While the interspecies hybrids appeared to be sterile, the intraspecies hybrids were able to produce backcross and outcross progeny. Analysis of 5 backcross and outcross progeny clones generated from an L. major F1 hybrid, as well as 17 progeny clones generated from backcrosses involving a natural hybrid of L. tropica, revealed genome wide patterns of recombination, demonstrating that classical crossing over occurs at meiosis, and allowed us to construct the first physical and genetic maps in Leishmania. Altogether, the findings provide strong evidence for meiosis-like sexual recombination in Leishmania, presenting clear opportunities for forward genetic analysis and positional cloning of important genes.

Citrullus colocynthis (L.) Schrad seeds generally called Egusi melon are widely eaten in Nigeria, but its uses in post-harvest crop protection have not been exploited. The effects of the edible oil of C. colocynthis seeds on Callosobruchus maculatus (F.) were assessed on adult mortality, oviposition, F1 progeny emergence, cowpea seed damage and seed germinability in the laboratory. Results indicated that the oil showed some lethal effects on treated insects at above 50% mortality and very high reduction in oviposition at increased concentrations. Seeds treated with the oil showed significant (P

Leishmaniasis remains one of the world's most neglected diseases, and early detection of the infectious agent, especially in developing countries, will require a simple and rapid test. In this study, we established a quick, one-step, single-tube, highly sensitive loop-mediated isothermal amplification (LAMP) assay for rapid detection of Leishmania DNA from tissue materials spotted on an FTA card. An FTA-LAMP with pre-added malachite green was performed at 64 degrees C for 60 mm using a heating block and/or water bath and DNA amplification was detected immediately after incubation. The LAMP assay had high detection sensitivity down to a level of 0.01 parasites per mu l. The field- and clinic-applicability of the colorimetric FTA-LAMP assay was demonstrated with 122 clinical samples collected from patients suspected of having cutaneous leishmaniasis in Peru, from which 71 positives were detected. The LAMP assay in combination with an FTA card described here is rapid and sensitive, as well as simple to perform, and has great potential usefulness for diagnosis and surveillance of leishmaniasis in endemic areas. (C) 2015 Elsevier B.V. All rights reserved.

Phlebotomine sand flies are the only proven vectors of leishmaniases, a group of human and animal diseases. Accurate knowledge of sand fly species identification is essential in understanding the epidemiology of leishmaniasis and vector control in endemic areas. Classical identification of sand fly species based on morphological characteristics often remains difficult and requires taxonomic expertise. Here, we generated DNA barcodes of the cytochrome c oxidase subunit 1 (COI) gene using 159 adult specimens morphologically identified to be 19 species of sand flies, belonging to 6 subgenera/species groups circulating in Peru, including the vector species. Neighbor-joining (NJ) analysis based on Kimura 2-Parameter genetic distances formed non-overlapping clusters for all species. The levels of intraspecific genetic divergence ranged from 0 to 5.96%, whereas interspecific genetic divergence among different species ranged from 8.39 to 19.08%. The generated COI barcodes could discriminate between all the sand fly taxa. Besides its success in separating known species, we found that DNA barcoding is useful in revealing population differentiation and cryptic diversity, and thus promises to be a valuable tool for epidemiological studies of leishmaniasis. Copyright (C) 2015 Published by Elsevier B.V. All rights reserved.

Entomological monitoring of Leishmania infection in leishmaniasis endemic areas offers epidemiologic advantages for predicting the risk and expansion of the disease, as well as evaluation of the effectiveness of control programs. In this study, we developed a highly sensitive loop-mediated isothermal amplification (LAMP) method for the mass screening of sand flies for Leishmania infection based on the 18S rRNA gene. The LAMP technique could detect 0.01 parasites, which was more sensitive than classical PCR. The method was robust and could amplify the target DNA within 1 h from a crude sand fly template without DNA purification. Amplicon detection could be accomplished by the newly developed colorimetric malachite green (MG)—mediated naked eye visualization. Pre-addition of MG to the LAMP reaction solution did not inhibit amplification efficiency. The field applicability of the colorimetric MG-based LAMP assay was demonstrated with 397 field-caught samples from the endemic areas of Ecuador and eight positive sand flies were detected. The robustness, superior sensitivity, and ability to produce better visual discriminatory reaction products than existing LAMP fluorescence and turbidity assays indicated the field potential usefulness of this new method for surveillance and epidemiological studies of leishmaniasis in developing countries.