title: Vaccination with LiESP/QA-21 (CaniLeish®) reduces the intensity of infection in Phlebotomus perniciosus fed on Leishmania infantum infected dogs--a preliminary xenodiagnosis study.
abstract: Ten Beagle dogs at different stages of Leishmania infantum infection, among which 6 had received a full course of LiESP/QA-21 (CaniLeish(®); Virbac) vaccination, were exposed to the bites of reared Phlebotomus perniciosus to assesses their infectiousness potential. This was found to be negligible/nil in 2 seronegative dogs with subpatent infection. Among the 8 dogs with active infection (=positive serology, bone-marrow qualitative PCR and lymph node culture), 2/5 vaccinated (40.0%) and 2/3 nonvaccinated dogs (66.7%) were infectious to the sand flies (p=0.5). However significantly fewer of the sand flies which fed on the vaccinated dogs were infected when compared to those which fed on the control dogs (10/82 compared to 30/49) (chi-squared test, p<0.0001; mixed binomial model with the dog identity included as a random effect, p=0.03). Furthermore, there was a significant difference in the proportion of sand flies with >500 parasites in their gut (i.e. a higher risk for subsequent transmission): 3.7% for vaccinated dogs compared with 28.6% for nonvaccinated dogs (Fisher's exact test, p<0.0001; binomial mixed model, p=0.006). Although preliminary, these results suggest value in further investigations on L. infantum transmissibility parameters in LiESP/QA-21 vaccinated dogs.
authors.affiliation: Unit of Vector-borne Diseases and International Health, MIPI Department, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.
authors.forename: Gioia
authors.initials: G
authors.lastname: Bongiorno
authors.forename: Rosa
authors.initials: R
authors.lastname: Paparcone
authors.forename: Valentina
authors.initials: V
authors.lastname: Foglia Manzillo
authors.forename: Gaetano
authors.initials: G
authors.lastname: Oliva
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Cuisinier
authors.forename: Luigi
authors.initials: L
authors.lastname: Gradoni
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000469:parasitology / Q000517:prevention & control*; D004285:Dogs; D006790:Host-Parasite Interactions; D007115:Immunization Schedule; D018314:Leishmania infantum / Q000276:immunology*; D007898:Leishmaniasis, Visceral / Q000517:prevention & control / Q000662:veterinary*; D010691:Phlebotomus / Q000469:parasitology*; D014611:Vaccination
keywords: Canine leishmaniosis; Leishmania infantum; LiESP/QA-21 vaccine; Phlebotomus perniciosus; Xenodiagnosis