The prevalence of antibodies against B. burgdorferi, an indicator for Lyme borreliosis in dogs? A comparison of serological tests.

: Five serological tests for the detection of IgM and IgG antibodies to Borrelia burgdorferi, the causative microorganism of Lyme borreliosis (LB), were compared in 1177 sera from Dutch dogs: 401 healthy working hunting dogs, 100 healthy city pet dogs, 629 city dogs suspected of having LB with various clinical symptoms, and 47 hunting dogs with intermittent lameness. The results of the in-house species-independent enzyme immunoassay (i.e. an EIA which can be used to test serum samples from different animal species) showed a strong agreement (kappa: 0.78-0.81) with those of an experimental and a commercially available EIA (Genzyme Virotech, Russelsheim, Germany) for the detection of canine IgG antibodies to B. burgdorferi. Furthermore, the sensitivity of the in-house EIAs for the detection of antibodies to B. burgdorferi was independent of the antigenic heterogeneity, as demonstrated by the results of sera from dogs suspected of LB with various clinical symptoms: lameness (n = 60), and neurological (n = 60) and skin disorders (n = 52). Because of its high sensitivity for IgM antibodies, the indirect assay (Diagast, Pessac, France) proved to be an interesting tool for the detection of an acute Lyme infection in dogs. However, in this study a positive serological result could not be linked to any clinical symptom that has been related to LB in dogs. Results showed no difference in seroprevalence between dogs considered at high or at low risk of a B. burgdorferi infection. It was concluded that LB is an uncommon disease in the Dutch dog population despite the fact that many of Dutch dogs are infected with B. burgdorferi. Because of this low prevalence, the use of any immunoassay to support the clinical diagnosis of LB in dogs might be of limited value. Nevertheless, the species-independent EIA could be valuable in seroepidemiological studies when sera of several different animal species need to be tested.