Research
Background
Canine parvovirus type 2 (CPV2) is an important pathogen for domestic dogs. It causes severe acute gastroenteritis and, more rarely, fatal myocarditis in young dogs. CPV2 was first isolated in 1978 and was found to spread rapidly throughout the world.1 Since the early 1980s, several mutations have taken place in CPV2 resulting in the more recent antigenic types CPV2a, CPV2b and CPV2c.2 It is thought that improved receptor binding led to the selection of those mutants.3 The original CPV2 strain now appears to be extinct in the field.4 Vanguard® 7, a multivalent dog vaccine that is sold in the EU contains, amongst other antigens, live attenuated CPV2. The vaccine was developed in the late 1970s, and has been shown to help prevent clinical signs and reduce fecal excretion due to CPV2 infection.5 The aim of this study was to demonstrate that the live attenuated CPV2 strain NL-35-D in Vanguard® 7 is able to help protect young dogs against a challenge with a more recent virulent CPV2c field strain.6
1. Appel MJG, Scott FW, Carmichael LE. Isolation and immunization studies of canine parvo-like virus from dogs with hemorrhagic enteritis. Vet Rec 1979;105:156-159.
2. Truyen U. Evolution of canine parvovirus – A need for new vaccines? Vet Microbiol 2006;117:9 13.
3. Hueffer K, Parish CR. Parvovirus host range, celltropism and evolution. Curr Opin Microbiol 2003;6:392-398.
4. Battilani M, Ciulli S, Tisato E, Prosperi S. Genetic analysis of canine parvovirus isolates (CPV-2) from dogs in Italy. Virus Res 2002;83:149 157.
5. Data on file, Study Report No. V7E6, Pfizer Inc.
6. Data on file, Study Report No. 9161R-10-06-209, Pfizer Inc.
