Leishmune vaccine blocks the transmission of canine visceral leishmaniasis: absence of Leishmania parasites in blood, skin and lymph nodes of vaccinated exposed dogs.
Leishmune vaccine is the first licensed vaccine against canine visceral leishmaniasis. It contains the Fucose-Mannose-ligand (FML) antigen of Leishmania donovani. The potential Leishmune vaccine effect on the interruption of the transmission of the disease, was assayed by monitoring, in untreated (n=40) and vaccinated dogs (n=32) of a Brazilian epidemic area: the kala-azar clinical signs, the FML-seropositivity and the Leishmania parasite evidence by immunohistochemistry of skin and PCR for Leishmanial DNA of lymph node and blood samples. On month 11 after vaccination, untreated controls showed: 25% of symptomatic cases, 50% of FML-seropositivity, 56.7% of lymph node PCR, 15.7% of blood PCR and 25% of immunohistochemical positive reactions. The Leishmune-vaccinated dogs showed 100% of seropositivity to FML and a complete absence of clinical signs and of parasites (0%) in skin, lymph node and blood PCR samples (p<0.01). The positivity in FML-ELISA in untreated dogs significantly correlates with the PCR in lymph node samples (p<0.001) and with the increase in number of symptoms (p=0.006) being strong markers of infectiousness. The absence of symptoms and of evidence of Leishmania DNA and parasites in Leishmune-vaccinated animals indicates the non-infectious condition of the Leishmune-vaccinated dogs.
Nogueira
F S
FS
Faculdade de Medicina Veterinária e Zootecnia, Universidade Estadual Paulista "Júlio de Mesquita Filho", UNESP-Botucatu Distrito Rubião Jr. s/n Botucatu SP CEP 18600-000, Brazil.
Moreira
M A B
MA
Borja-Cabrera
G P
GP
Santos
F N
FN
Menz
I
I
Parra
L E
LE
Xu
Z
Z
Chu
H J
HJ
Palatnik-de-Sousa
C B
CB
Luvizotto
M C R
MC
D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000276:immunology; D016054:DNA, Protozoan / Q000032:analysis; D004283:Dog Diseases / Q000276:immunology / Q000469:parasitology* / Q000517:prevention & control; D004285:Dogs; D004797:Enzyme-Linked Immunosorbent Assay; D007120:Immunochemistry; D037102:Lectins / Q000276:immunology; D007891:Leishmania / Q000276:immunology*; D007898:Leishmaniasis, Visceral / Q000517:prevention & control / Q000635:transmission / Q000662:veterinary*; D008198:Lymph Nodes / Q000469:parasitology; D016133:Polymerase Chain Reaction; D015800:Protozoan Proteins / Q000032:analysis; D016052:Protozoan Vaccines / Q000008:administration & dosage / Q000276:immunology*; D012867:Skin / Q000469:parasitology
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D016054:DNA, Protozoan; D037102:Lectins; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; C027112:fucose-binding lectin