Testing dogs for immunity against Canine Parvovirus, Canine Distemper Virus and Infectious Canine Hepatitis
Jørgen Damkjer Lund, Merete Prior and Lars Madsen
BARF – Danish Raw Feeding Center - Selsøvej 31, 4050 Skibby, Denmark
Summary
The aim of the study was 1) to describe the distributions of scores for the level of immunity against Parvovirus (CPV), Canine Distemper Virus (CDV), and Infectious Canine Hepatitis (ICH) for dogs tested in the veterinary clinic of the Danish Raw Feeding Center, 2) to describe the relationships between the levels of immunity against these diseases, and 3) to identify factors influencing the risk of insufficient immunity.
The study includes 322 dogs of which 225 were tested once, 67 were tested twice, 24 were tested three times, 5 were tested four times, and 1 was tested five times. Thus, a total of 456 tests were performed.
When tested for the first time the proportions of dogs found protected against CPV, CDV and ICH individually were 88.5 %, 87.3 % and 85.1 %, respectively, corresponding to estimated true prevalences of dogs protected against these diseases of 91.2 %, 91.9 % and 87.8 %, given the sensitivity and specificity of the tests. The proportion of dogs found protected against all diseases was 74.8 %.
Pure bred dogs had significantly lower risk of insufficient immunity against ICH as compared to dogs of mixed breeds (OR = 0.41). Additionally, pure bred dogs tended to have lower risk of insufficient immunity against CPV (OR = 0.47; p = 0.056). Male dogs had significantly higher risk of insufficient immunity against ICH as compared to females (OR = 1.94), and dogs with body weights of 0 – 10 kg had significantly higher risk of insufficient immunity against CPV as compared to dogs with body weights of more than 30 kg (OR = 3.17)
Furthermore, significant associations were found between age and immunity status. Compared to dogs more than 3 y old, dogs younger than 1 y had higher risk of insufficient immunity against CPV (OR = 5.90) and ICH (OR = 3.10), and dogs >1 to 3 y old had higher risk of insufficient immunity against CDV (OR = 3.29) and ICH (2.77). The proportions of dogs younger than 1 y found unprotected were 25.3 %, 12.6 % and 20.7 % for CPV, CDV and ICH, respectively. The corresponding estimated true prevalences of unprotected dogs were 23.0 %, 8.0 % and 19.3 %, given the sensitivity and specificity of the tests.
Our results indicate that about 3/4 of the dogs revaccinated against CPV, CDV and ICH every year will have adequate immunity against these diseases and do not need to be revaccinated. Test of dogs for immunity against CPV, CDV and ICH once a year in the clinic may help to ensure that these dogs are not over-vaccinated. Furthermore, dogs not responding adequately to vaccination may be identified, if the immunity status of vaccinated dogs is tested 1 mo after vaccination. However, to ensure that no dogs receive vaccines against diseases for which, they are already protected, monovalent vaccines against CDV and ICH are relevant.
