title: Duration of serological response to canine parvovirus-type 2, canine distemper virus, canine adenovirus type 1 and canine parainfluenza virus in client-owned dogs in Australia.
abstract: OBJECTIVE
  To determine whether client-owned dogs in Australia, last vaccinated with Canvac(®) vaccines containing canine parvovirus-type 2 (CPV-2), canine distemper virus (CDV), canine adenovirus type 2 (CAV-2) ± canine parainfluenza virus (CPiV) at least 18 months ago, were seropositive or responded serologically to revaccination.
  
  
  METHODS
  A total of 235 dogs were recruited from 23 veterinary clinics, representing a variety of breeds, ages and time since last vaccination (TSLV: range 1.5-9 years, mean 2.8 years). Dogs had a blood sample taken and were revaccinated on day 0. A second blood sample was taken 7-14 days later. Blood samples were assessed for antibody titres to CPV-2 (by haemagglutination inhibition) and CDV, CAV type 1 (CAV-1) and CPiV (by virus neutralisation). Dogs with a day 0 titre >10 or a four-fold increase in titre following revaccination were considered to be serological responders.
  
  
  RESULTS
  The overall percentage of dogs classified as serological responders was 98.7% for CPV-2, 96.6% for CDV, 99.6% for CAV-1 and 90.3% for CPiV.
  
  
  CONCLUSIONS
  These results suggest that the duration of serological response induced by modified-live vaccines against CPV-2, CDV, CAV-1 and CPiV, including Canvac(®) vaccines, is beyond 18 months and may extend up to 9 years. Accordingly, these vaccines may be considered for use in extended revaccination interval protocols as recommended by current canine vaccine guidelines.
authors.affiliation: Pfizer Animal Health, 38-42 Wharf Road, West Ryde, New South Wales 2114, Australia. sarah.mitchell@pfizer.com
authors.forename: S A
authors.initials: SA
authors.lastname: Mitchell
authors.forename: R J
authors.initials: RJ
authors.lastname: Zwijnenberg
authors.forename: J
authors.initials: J
authors.lastname: Huang
authors.forename: A
authors.initials: A
authors.lastname: Hodge
authors.forename: M J
authors.initials: MJ
authors.lastname: Day
mesh_terms: D000256:Adenoviridae / Q000276:immunology; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D001315:Australia; D004217:Distemper Virus, Canine / Q000276:immunology; D004283:Dog Diseases / Q000517:prevention & control* / Q000821:virology; D004285:Dogs; D005260:Female; D006386:Hemagglutination Tests / Q000662:veterinary; D008297:Male; D009500:Neutralization Tests / Q000662:veterinary; D017993:Parvovirus, Canine / Q000276:immunology; D018108:Respirovirus / Q000276:immunology; D016036:Seroepidemiologic Studies; D013997:Time Factors; D014765:Viral Vaccines / Q000276:immunology*; D014777:Virus Diseases / Q000517:prevention & control / Q000662:veterinary*
chemical_list: D000914:Antibodies, Viral; D014765:Viral Vaccines