title: Comparison of two commercial vaccines against visceral leishmaniasis in dogs from endemic areas: IgG, and subclasses, parasitism, and parasite transmission by xenodiagnosis.
abstract: BACKGROUND
  The incidence of zoonotic canine visceral leishmaniasis (CVL) would decrease if dogs were effectively vaccinated; however, additional data on the efficacy of canine vaccines are required for their approved preventative use.
  
  
  OBJECTIVE
  To prospectively evaluate vaccination outcomes using two products commercially available in Brazil, with respect to adverse reactions (reactogenicity), humoral response, disease signs, parasitism, and parasite infectiousness in naturally exposed pet dogs in an endemic area of visceral leishmaniasis (VL).
  
  
  METHODS
  From 2010 to 2012, healthy dogs were vaccinated with Leishmune(®) (50 animals) or Leish-Tec(®) (50 animals). Each dog was examined to identify clinical signs during peri- and post-vaccination procedures every 2 months for 11 months to identify the presence of parasites or parasite DNA in splenic samples using culturing or PCR, respectively. Levels of anti-Leishmania IgG, IgG1, and IgG2 were quantified in sera by ELISA and infectiousness was assessed by xenodiagnosis.
  
  
  RESULTS
  Adverse effects occurred in 2.2% (1/45) and 13.0% (6/46) of the animals in the Leishmune(®) and Leish-Tec(®) groups, respectively. IgG levels peaked on the 21st day following the first dose of Leishmune(®) and on the 21st day after the second dose of Leish-Tec(®). The final seropositivity rate for IgG was 32.5% (13/40) and 30.9% (13/42) in the Leishmune(®) and Leish-Tec(®) groups, respectively. The Leishmune(®) group presented higher levels of IgG1 and IgG2 compared to the Leish-Tec(®) group (p<0.001), and ELISA reactivity in both vaccinated groups was significantly lower (p<0.001) than in infected positive control dogs. Parasitism was observed in 12.2% (5/41) of the Leishmune(®) group, and 7.9% (3/38) of the Leish-Tec(®) group, with xenodiagnostic transmission rates of Leishmania to Lutzomyia longipalpis of 5.1% (2/39), and 5.4% (2/37), respectively.
  
  
  CONCLUSIONS
  No significant differences were observed in dogs vaccinated with Leishmune(®) or Leish-Tec(®), with respect to LVC clinical aspects, parasitism, IgG seropositivity, or dog infectiousness. The Leishmune(®)-vaccinated animals presented higher levels of IgG, IgG1, and IgG2. The animals vaccinated with Leish-Tec(®) exhibited adverse reactions with greater frequency and severity.
authors.affiliation: Laboratory of Veterinary Infectious Diseases, Hospital of Veterinary Medicine (HOSPMEV), Federal University of Bahia (UFBA), Salvador, BA, Brazil.
authors.forename: Consuelo Barreto
authors.initials: CB
authors.lastname: Fernandes
authors.affiliation: Laboratory of Veterinary Infectious Diseases, Hospital of Veterinary Medicine (HOSPMEV), Federal University of Bahia (UFBA), Salvador, BA, Brazil.
authors.forename: Jairo Torres Magalhães
authors.initials: JT
authors.lastname: Junior
authors.affiliation: Laboratory of Veterinary Infectious Diseases, Hospital of Veterinary Medicine (HOSPMEV), Federal University of Bahia (UFBA), Salvador, BA, Brazil.
authors.forename: Clauceane
authors.initials: C
authors.lastname: de Jesus
authors.affiliation: Laboratory of Cellular and Molecular Biology, HOSPMEV, UFBA, Salvador, BA, Brazil.
authors.forename: Bárbara Maria Paraná da Silva
authors.initials: BM
authors.lastname: Souza
authors.affiliation: Laboratory of Veterinary Infectious Diseases, Hospital of Veterinary Medicine (HOSPMEV), Federal University of Bahia (UFBA), Salvador, BA, Brazil; Departament of Veterinary Anatomy, Pathology and Clinics of the School of Veterinary Medicine and Zootechny, UFBA, Salvador, BA, Brazil.
authors.forename: Daniela Farias
authors.initials: DF
authors.lastname: Larangeira
authors.affiliation: Departament of Preventive Veterinary Medicine and Animal Production of the School of Veterinary Medicine and Zootechny, UFBA, Salvador, BA, Brazil; Laboratory of Pathology and Bio-Intervention, Gonçalo Moniz Research Center-Oswaldo Cruz Foundation-FIOCRUZ/BA, Salvador, BA, Brazil.
authors.forename: Deborah Bittencourt Mothé
authors.initials: DB
authors.lastname: Fraga
authors.affiliation: Laboratory of Pathology and Bio-Intervention, Gonçalo Moniz Research Center-Oswaldo Cruz Foundation-FIOCRUZ/BA, Salvador, BA, Brazil.
authors.forename: Patricia Sampaio
authors.initials: PS
authors.lastname: Tavares Veras
authors.affiliation: Laboratory of Veterinary Infectious Diseases, Hospital of Veterinary Medicine (HOSPMEV), Federal University of Bahia (UFBA), Salvador, BA, Brazil; Departament of Veterinary Anatomy, Pathology and Clinics of the School of Veterinary Medicine and Zootechny, UFBA, Salvador, BA, Brazil. Electronic address: barrouin@ufba.br.
authors.forename: Stella Maria
authors.initials: SM
authors.lastname: Barrouin-Melo
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D001938:Brazil; D004283:Dog Diseases / Q000469:parasitology / Q000517:prevention & control*; D004285:Dogs; D005260:Female; D056724:Immunity, Humoral; D007074:Immunoglobulin G / Q000097:blood; D054332:Leishmaniasis Vaccines / Q000009:adverse effects / Q000627:therapeutic use*; D007898:Leishmaniasis, Visceral / Q000175:diagnosis / Q000517:prevention & control* / Q000662:veterinary; D008297:Male; D011446:Prospective Studies; D014611:Vaccination / Q000662:veterinary; D020525:Xenodiagnosis
chemical_list: D000913:Antibodies, Protozoan; D007074:Immunoglobulin G; D054332:Leishmaniasis Vaccines
keywords: Canine immunization; Leishmania infantum; Leishmune(®) and Leish-Tec(®); Lutzomyia longipalpis; Reactogenicity; Xenodiagnosis