Fifteen-month duration of immunity for the serovar Grippotyphosa fraction of a tetravalent canine leptospirosis vaccine.

Forty-four specific pathogen-free beagles, median age 65 days, received two subcutaneous doses of either a commercially available, five-way combination vaccine or the same vaccine in combination with a tetravalent bacterin (Canicola, Grippotyphosa, Icterohaemorrhagiae, Pomona). They were subsequently challenged with a pathogenic strain serovar Grippotyphosa 470 days following completion of the vaccination protocol. Titres of agglutinating serum antibodies were determined at various time points before and after both vaccination and challenge, along with postchallenge reisolation of the challenge organisms from blood and urine, and evaluation of renal histopathology.

Development and registration of recombinant veterinary vaccines. The example of the canarypox vector platform.

The canarypox vaccine vector (ALVAC) technology has been used to develop and license several vaccines for companion animals and horses in the European Union and USA. ALVAC is a ubiquitous vector with high biosafety since it is non-replicative in mammalians, is genetically and physically stable, and able to induce both humoral and cell-mediated immune responses against the expressed transgene product. Specific rules apply for the development and registration of recombinant vector vaccines.