title: New Insights Into the Transmissibility of Leishmania infantum From Dogs to Sand Flies: Experimental Vector-Transmission Reveals Persistent Parasite Depots at Bite Sites.
abstract: Canine leishmaniasis (CanL) is a chronic fatal disease of dogs and a major source of human infection through propagation of parasites in vectors. Here, we infected 8 beagles through multiple experimental vector transmissions with Leishmania infantum-infected Lutzomyia longipalpis. CanL clinical signs varied, although live parasites were recovered from all dog spleens. Splenic parasite burdens correlated positively with Leishmania-specific interleukin 10 levels, negatively with Leishmania-specific interferon γ and interleukin 2 levels, and negatively with Leishmania skin test reactivity. A key finding was parasite persistence for 6 months in lesions observed at the bite sites in all dogs. These recrudesced following a second transmission performed at a distal site. Notably, sand flies efficiently acquired parasites after feeding on lesions at the primary bite site. In this study, controlled vector transmissions identify a potentially unappreciated role for skin at infectious bite sites in dogs with CanL, providing a new perspective regarding the mechanism of Leishmania transmissibility to vector sand flies.
authors.affiliation: Vector Molecular Biology Section, Laboratory of Malaria and Vector Research Faculty of Health Science, Selahaddin Eyyubi University, Diyarbakir, Turkey.
authors.forename: Hamide
authors.initials: H
authors.lastname: Aslan
authors.affiliation: Vector Molecular Biology Section, Laboratory of Malaria and Vector Research.
authors.forename: Fabiano
authors.initials: F
authors.lastname: Oliveira
authors.affiliation: Vector Molecular Biology Section, Laboratory of Malaria and Vector Research.
authors.forename: Claudio
authors.initials: C
authors.lastname: Meneses
authors.affiliation: Vector Molecular Biology Section, Laboratory of Malaria and Vector Research.
authors.forename: Philip
authors.initials: P
authors.lastname: Castrovinci
authors.affiliation: Vector Molecular Biology Section, Laboratory of Malaria and Vector Research Fundação Oswaldo Cruz, Escritório Regional da Fiocruz Piauí, Teresina, Brazil.
authors.forename: Regis
authors.initials: R
authors.lastname: Gomes
authors.affiliation: Vector Molecular Biology Section, Laboratory of Malaria and Vector Research Fundação Oswaldo Cruz, Escritório Regional da Fiocruz Piauí, Teresina, Brazil.
authors.forename: Clarissa
authors.initials: C
authors.lastname: Teixeira
authors.affiliation: Vector Molecular Biology Section, Laboratory of Malaria and Vector Research.
authors.forename: Candace A
authors.initials: CA
authors.lastname: Derenge
authors.affiliation: Comparative Medicine Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland.
authors.forename: Marlene
authors.initials: M
authors.lastname: Orandle
authors.affiliation: Unit of Vector-Borne Diseases and International Health, Istituto Superiore di Sanità, Rome.
authors.forename: Luigi
authors.initials: L
authors.lastname: Gradoni
authors.affiliation: Department of Veterinary Medicine and Animal Productions, University Federico II, Naples, Italy.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Oliva
authors.affiliation: Merial S.A.S., R&D, Laboratoire de Lyon Gerland, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Fischer
authors.affiliation: Vector Molecular Biology Section, Laboratory of Malaria and Vector Research.
authors.forename: Jesus G
authors.initials: JG
authors.lastname: Valenzuela
authors.affiliation: Vector Molecular Biology Section, Laboratory of Malaria and Vector Research.
authors.forename: Shaden
authors.initials: S
authors.lastname: Kamhawi
mesh_terms: D000818:Animals; D004197:Disease Reservoirs / Q000662:veterinary; D004283:Dog Diseases / Q000276:immunology / Q000469:parasitology* / Q000473:pathology / Q000635:transmission; D004285:Dogs; D005260:Female; D006801:Humans; D007111:Immunity, Cellular; D056724:Immunity, Humoral; D007299:Insect Bites and Stings / Q000469:parasitology / Q000473:pathology / Q000662:veterinary; D007303:Insect Vectors / Q000469:parasitology*; D007371:Interferon-gamma / Q000378:metabolism; D018314:Leishmania infantum / Q000302:isolation & purification; D007898:Leishmaniasis, Visceral / Q000469:parasitology / Q000473:pathology / Q000635:transmission / Q000662:veterinary*; D011576:Psychodidae / Q000469:parasitology*; D012867:Skin / Q000469:parasitology; D013154:Spleen / Q000469:parasitology
chemical_list: D007371:Interferon-gamma
keywords: Leishmania infantum; Lutzomyia longipalpis; bite site; canine leishmaniasis; dogs; infectivity; parasite-pickup; reservoir; skin; vector transmission