title: Leishmania detection in sand flies using a field-deployable real-time analytic system.
abstract: We describe here the development and evaluation of advanced vector surveillance analytic technologies for real-time leishmaniasis risk assessment. Leishmania genus and visceral leishmaniasis causative agent--specific dual fluorogenic-probe hydrolysis (TaqMan), thermally stable (freeze-dried) polymerase chain reaction assays were developed using field-durable analytic instrumentation. In laboratory testing with a panel of diverse Leishmania species from culture and infected sand flies, the sensitivity and specificity of both assays were 100% concordant with DNA sequencing. In specificity testing with Leishmania genetic near neighbors, clinically significant organisms, and human genomic DNA, no detectable fluorescence above background was observed. Field evaluation was conducted in southern Iraq using wild sand flies. In field testing, Leishmania genus assay was 100% sensitive and 96% specific with a single false-positive result. The visceral leishmaniasis genotype assay was 100% sensitive and 100% specific compared to DNA sequencing. Thermally stable polymerase chain reaction assays vastly simplified transportation and storage. Assay preparation and analysis required less than 2 hours.
authors.affiliation: Division of Entomology, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA.
authors.forename: James C
authors.initials: JC
authors.lastname: McAvin
authors.forename: Katherine I
authors.initials: KI
authors.lastname: Swanson
authors.forename: Adeline S T
authors.initials: AS
authors.lastname: Chan
authors.forename: Miguel
authors.initials: M
authors.lastname: Quintana
authors.forename: Russell E
authors.initials: RE
authors.lastname: Coleman
mesh_terms: D000818:Animals; D003199:Computer Systems; D016054:DNA, Protozoan / Q000302:isolation & purification; D006801:Humans; D007493:Iraq; D007891:Leishmania / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D007896:Leishmaniasis / Q000175:diagnosis / Q000235:genetics / Q000469:parasitology* / Q000635:transmission; D007898:Leishmaniasis, Visceral / Q000469:parasitology; D008887:Military Medicine; D016133:Polymerase Chain Reaction; D011159:Population Surveillance; D011237:Predictive Value of Tests; D011576:Psychodidae / Q000469:parasitology*; D018570:Risk Assessment; D012680:Sensitivity and Specificity
chemical_list: D016054:DNA, Protozoan