Erasmus J.H.,University of Texas Medical Branch |
Needham J.,InBios International, Inc. |
Raychaudhuri S.,InBios International, Inc. |
Diamond M.S.,University of Washington |
And 9 more authors.
PLoS Neglected Tropical Diseases | Year: 2015
In December of 2013, chikungunya virus (CHIKV), an alphavirus in the family Togaviridae, was introduced to the island of Saint Martin in the Caribbean, resulting in the first autochthonous cases reported in the Americas. As of January 2015, local and imported CHIKV has been reported in 50 American countries with over 1.1 million suspected cases. CHIKV causes a severe arthralgic disease for which there are no approved vaccines or therapeutics. Furthermore, the lack of a commercially available, sensitive, and affordable diagnostic assay limits surveillance and control efforts. To address this issue, we utilized an insect-specific alphavirus, Eilat virus (EILV), to develop a diagnostic antigen that does not require biosafety containment facilities to produce. We demonstrated that EILV/CHIKV replicates to high titers in insect cells and can be applied directly in enzyme-linked immunosorbent assays without inactivation, resulting in highly sensitive detection of recent and past CHIKV infection, and outperforming traditional antigen preparations. © 2015, Public Library of Science. All rights reserved.
Gloria-Soria A.,Yale University |
Ayala D.,CIRAD - Agricultural Research for Development |
Ayala D.,Center International Of Recherches Medicales Of Franceville |
Bheecarry A.,Ministry of Health and Quality of Life |
And 25 more authors.
Molecular Ecology | Year: 2016
Mosquitoes, especially Aedes aegypti, are becoming important models for studying invasion biology. We characterized genetic variation at 12 microsatellite loci in 79 populations of Ae. aegypti from 30 countries in six continents, and used them to infer historical and modern patterns of invasion. Our results support the two subspecies Ae. aegypti formosus and Ae. aegypti aegypti as genetically distinct units. Ae. aegypti aegypti populations outside Africa are derived from ancestral African populations and are monophyletic. The two subspecies co-occur in both East Africa (Kenya) and West Africa (Senegal). In rural/forest settings (Rabai District of Kenya), the two subspecies remain genetically distinct, whereas in urban settings, they introgress freely. Populations outside Africa are highly genetically structured likely due to a combination of recent founder effects, discrete discontinuous habitats and low migration rates. Ancestral populations in sub-Saharan Africa are less genetically structured, as are the populations in Asia. Introduction of Ae. aegypti to the New World coinciding with trans-Atlantic shipping in the 16th to 18th centuries was followed by its introduction to Asia in the late 19th century from the New World or from now extinct populations in the Mediterranean Basin. Aedes mascarensis is a genetically distinct sister species to Ae. aegypti s.l. This study provides a reference database of genetic diversity that can be used to determine the likely origin of new introductions that occur regularly for this invasive species. The genetic uniqueness of many populations and regions has important implications for attempts to control Ae. aegypti, especially for the methods using genetic modification of populations. © 2016 John Wiley & Sons Ltd
PubMed | University of Witwatersrand, Dallah Establishment, Kenya Medical Research Institute, King Saud University and 15 more.
Type: Journal Article | Journal: Molecular ecology | Year: 2016
Mosquitoes, especially Aedes aegypti, are becoming important models for studying invasion biology. We characterized genetic variation at 12 microsatellite loci in 79 populations of Ae.aegypti from 30 countries in six continents, and used them to infer historical and modern patterns of invasion. Our results support the two subspecies Ae.aegypti formosus and Ae.aegypti aegypti as genetically distinct units. Ae.aegypti aegypti populations outside Africa are derived from ancestral African populations and are monophyletic. The two subspecies co-occur in both East Africa (Kenya) and West Africa (Senegal). In rural/forest settings (Rabai District of Kenya), the two subspecies remain genetically distinct, whereas in urban settings, they introgress freely. Populations outside Africa are highly genetically structured likely due to a combination of recent founder effects, discrete discontinuous habitats and low migration rates. Ancestral populations in sub-Saharan Africa are less genetically structured, as are the populations in Asia. Introduction of Ae.aegypti to the New World coinciding with trans-Atlantic shipping in the 16th to 18th centuries was followed by its introduction to Asia in the late 19th century from the New World or from now extinct populations in the Mediterranean Basin. Aedes mascarensis is a genetically distinct sister species to Ae.aegypti s.l. This study provides a reference database of genetic diversity that can be used to determine the likely origin of new introductions that occur regularly for this invasive species. The genetic uniqueness of many populations and regions has important implications for attempts to control Ae.aegypti, especially for the methods using genetic modification of populations.
Argueta A.L.,Autonomous University of Chiapas |
Valle J.,COSUR |
Marina C.F.,Centro Regional Of Investigacion En Salud Publica Insp
Revista Colombiana de Entomologia | Year: 2011
The ovicidal and larvicidal effects of spinosad were studied in Aedes aegypti treated with concentrations of 0.1, 5 y 10 ppm spinosad (Tracer 480SC) during different periods of exposure at a constant temperature of 25±1°C. In a first experiment the ovicidal effects were low (6.6-8.2% of non-eclosion averaged over 12-96h exposure periods), whereas in a second experiment ovicidal effects were moderate (27,9 - 31,9% of non-eclosion in eggs exposed to spinosad suspension of 1-12 weeks old). Mortality of larvae increased significantly with increasing concentration and increasing duration of exposure to this product. Although spinosad has clear applications as a mosquito control product for control of vectors such as A. aegypti, it is clear that its vector control potential resides in its larvicidal effects rather than its ovicidal activity.
Barrows N.J.,University of Texas Medical Branch |
Campos R.K.,University of Texas Medical Branch |
Powell S.T.,University of Texas Medical Branch |
Prasanth K.R.,University of Texas Medical Branch |
And 15 more authors.
Cell Host and Microbe | Year: 2016
Currently there are no approved vaccines or specific therapies to prevent or treat Zika virus (ZIKV) infection. We interrogated a library of FDA-approved drugs for their ability to block infection of human HuH-7 cells by a newly isolated ZIKV strain (ZIKV MEX_I_7). More than 20 out of 774 tested compounds decreased ZIKV infection in our in vitro screening assay. Selected compounds were further validated for inhibition of ZIKV infection in human cervical, placental, and neural stem cell lines, as well as primary human amnion cells. Established anti-flaviviral drugs (e.g., bortezomib and mycophenolic acid) and others that had no previously known antiviral activity (e.g., daptomycin) were identified as inhibitors of ZIKV infection. Several drugs reduced ZIKV infection across multiple cell types. This study identifies drugs that could be tested in clinical studies of ZIKV infection and provides a resource of small molecules to study ZIKV pathogenesis. Currently there is no approved therapy to treat Zika virus (ZIKV) infection. Barrows et al. present a screen of FDA-approved drugs for anti-ZIKV activity in a hepatoma cell line. Selected compounds from the more than 20 identified candidates were validated in human neural stem cells and primary amnion cells. © 2016 Elsevier Inc.
May-Concha I.,CONICET |
May-Concha I.,Centro Regional Of Investigacion En Salud Publica Insp |
Guerenstein P.G.,CONICET |
Ramsey J.M.,Centro Regional Of Investigacion En Salud Publica Insp |
And 2 more authors.
Infection, Genetics and Evolution | Year: 2016
Triatoma dimidiata (Latreille) is a species complex that spans North, Central, and South America and which is a key vector of all known discrete typing units (DTU) of Trypanosoma cruzi, the etiologic agent of Chagas disease. Morphological and genetic studies indicate that T. dimidiata is a species complex with three principal haplogroups (hg) in Mexico. Different markers and traits are still inconclusive regarding if other morphological differentiation may indicate probable behavioral and vectorial divergences within this complex. In this paper we compared the antennae of three Mexican haplogroups (previously verified by molecular markers ND4 and ITS-2) and discussed possible relationships with their capacity to disperse and colonized new habitats. The abundance of each type of sensillum (bristles, basiconics, thick- and thin-walled trichoids) on the antennae of the three haplogroups, were measured under light microscopy and compared using Kruskal-Wallis non-parametric and multivariate non-parametric analyses. Discriminant analyses indicate significant differences among the antennal phenotype of haplogroups either for adults and some nymphal stages, indicating consistency of the character to analyze intraspecific variability within the complex. The present study shows that the adult antennal pedicel of the T. dimidiata complex have abundant chemosensory sensilla, according with good capacity for dispersal and invasion of different habitats also related to their high capacity to adapt to conserved as well as modified habitats. However, the numerical differences among the haplogroups are suggesting variations in that capacity. The results here presented support the evidence of T. dimidiata as a species complex but show females and males in a different way. Given the close link between the bug's sensory system and its habitat and host-seeking behavior, AP characterization could be useful to complement genetic, neurological and ethological studies of the closely related Dimidiata Complex haplogroups for a better knowledge of their vectorial capacity and a more robust species differentiation. © 2016.
Pech-May A.,Centro Regional Of Investigacion En Salud Publica Insp |
Pech-May A.,National Autonomous University of Mexico |
Marina C.F.,Centro Regional Of Investigacion En Salud Publica Insp |
Vazquez-Dominguez E.,National Autonomous University of Mexico |
And 7 more authors.
Infection, Genetics and Evolution | Year: 2013
The low dispersal capacity of sand flies could lead to population isolation due to geographic barriers, climate variation, or to population fragmentation associated with specific local habitats due to landscape modification. The phlebotomine sand fly Lutzomyia cruciata has a wide distribution throughout Mexico and is a vector of Leishmania mexicana in the southeast. The aim of this study was to evaluate the genetic diversity, structure, and divergence within and among populations of Lu. cruciata in the state of Chiapas, and to infer the intra-specific phylogeny using the 3' end of the mitochondrial cytochrome b gene. We analyzed 62 sequences from four Lu. cruciata populations and found 26 haplotypes, high genetic differentiation and restricted gene flow among populations (Fst= 0.416, Nm= 0.701, p< 0.001). The highest diversity values were recorded in populations from Loma Bonita and Guadalupe Miramar. Three lineages (100% bootstrap and 7% overall divergence) were identified using a maximum likelihood phylogenetic analysis which showed high genetic divergence (17.2-22.7%). A minimum spanning haplotype network also supported separation into three lineages. Genetic structure and divergence within and among Lu. cruciata populations are hence affected by geographic heterogeneity and evolutionary background. Data obtained in the present study suggest that Lu. cruciata in the state of Chiapas consists of at least three lineages. Such findings may have implications for vector capacity and hence for vector control strategies. © 2013 Elsevier B.V..
PubMed | University of Kansas and Centro Regional Of Investigacion En Salud Publica Insp
Type: Journal Article | Journal: Philosophical transactions of the Royal Society of London. Series B, Biological sciences | Year: 2015
Numerous recent studies have illuminated global distributions of human cases of dengue and other mosquito-transmitted diseases, yet the potential distributions of key vector species have not been incorporated integrally into those mapping efforts. Projections onto future conditions to illuminate potential distributional shifts in coming decades are similarly lacking, at least outside Europe. This study examined the global potential distributions of Aedes aegypti and Aedes albopictus in relation to climatic variation worldwide to develop ecological niche models that, in turn, allowed anticipation of possible changes in distributional patterns into the future. Results indicated complex global rearrangements of potential distributional areas, which--given the impressive dispersal abilities of these two species--are likely to translate into actual distributional shifts. This exercise also signalled a crucial priority: digitization and sharing of existing distributional data so that models of this sort can be developed more rigorously, as present availability of such data is fragmentary and woefully incomplete.
Bond J.G.,Centro Regional Of Investigacion En Salud Publica Insp |
Casas-Martinez M.,Centro Regional Of Investigacion En Salud Publica Insp |
Quiroz-Martinez H.,Autonomous University of Nuevo León |
Novelo-Gutierrez R.,Institute Ecologia AC |
And 5 more authors.
Parasites and Vectors | Year: 2014
Background: The abundance, richness and diversity of mosquitoes and aquatic insects associated with their oviposition sites were surveyed along eight states of the Pacific coast of Mexico. Diversity was estimated using the Shannon index (H'), similarity measures and cluster analysis. Methods. Oviposition sites were sampled during 2-3 months per year, over a three year period. Field collected larvae and pupae were reared and identified to species following adult emergence. Aquatic insects present at oviposition sites were also collected, counted and identified to species or genus. Results: In total, 15 genera and 74 species of mosquitoes were identified: Anopheles pseudopunctipennis, An. albimanus and Aedes aegypti were the most abundant and widely-distributed species, representing 47% of total mosquito individuals sampled. New species records for certain states are reported. Anopheline diversity was lowest in Sinaloa state (H' = 0.54) and highest in Chiapas (H' = 1.61) and Michoacán (H' = 1.56), whereas culicid diversity was lowest in Michoacán (H' = 1.93), Colima (H' = 1.95), Sinaloa (H' = 1.99) and Jalisco (H' = 2.01) and highest in Chiapas (H' = 2.66). In total, 10 orders, 57 families, 166 genera and 247 species of aquatic insects were identified in samples. Aquatic insect diversity was highest in Chiapas, Oaxaca and Michoacán (H' = 3.60-3.75). Mosquito larval/pupal abundance was not correlated with that of predatory Coleoptera and Hemiptera. Conclusion: This represents the first update on the diversity and geographic distribution of the mosquitoes and aquatic insects of Mexico in over five decades. This information has been cataloged in Mexico's National Biodiversity Information System (SNIB-CONABIO) for public inspection. © 2014 Bond et al.; licensee BioMed Central Ltd.