Canine parvovirus infection: which diagnostic test for virus?

Five laboratory tests for diagnosis of canine parvovirus type 2 (CPV-2) infection were employed to test 89 faecal samples collected from dogs with diarrhoea. The tests analysed were immunochromatography (IC), haemagglutination (HA), virus isolation (VI), conventional and real-time PCR. IC, HA, VI and conventional or real-time PCR were able, respectively, to detect CPV-2 antigen or nucleic acid in 41, 50, 54, 68 and 73 of the samples. The best correlation was found between conventional and real-time PCR, with an overall agreement of 94.38%. Sixty-eight samples that tested positive by HA, VI or conventional PCR were subjected to antigenic and/or genetic analyses of the CPV-2 strains by monoclonal antibody (MAb), restriction fragment-length polymorphism (RFLP) and/or sequence analyses. In sum, out of the 68 strains analysed, 26 were characterised as CPV-2a, 18 as CPV-2b and 24 as a CPV-2 Glu-426 mutant recently identified in Italy.