Canine vector-borne diseases (CVBDs) are caused by a diverse range of pathogens with variable biological behaviours that result in a wide spectrum of clinical presentations and laboratory abnormalities. For many reasons, the diagnosis of canine vector-borne infectious diseases can be challenging for clinicians. The objective of the present study was to compare serological and molecular tests for CVBD as the two most common methodologies used for the detection of healthy dogs or the diagnosis of sick dogs in which a vector-borne disease is suspected.
We used serological assays (Anaplasma spp., Babesia canis, Bartonella henselae, Bartonella vinsonii subsp. berkhoffii, Borrelia burgdorferi, Ehrlichia Canis, and SFG Rickettsia) and molecular assays to assess exposure or infection with 10 genera of CVBD-causing organisms (Anaplasma, Babesia, Bartonella, Borrelia, Ehrlichia, Francisella, Hemotropic Mycoplasma, Neorickettsia, Rickettsia, and Dirofilaria). Paired EDTA blood and serum samples from 30 clinically healthy dogs (Group I) and from 69 sick dogs suspected of having one or more canine vector-borne diseases (Groups II-IV) were tested in parallel to establish exposure or infection. with the specific CVBD targeted by this study.
Among all dogs tested (Groups I-IV), the molecular prevalences of individual CVBD pathogens ranged from 23.3 to 39.1%. Similarly, pathogen-specific seroprevalences ranged from 43.3% to 59.4% between healthy and diseased dogs (Groups I-IV). Among these representative sample sets, a panel combining serological and molecular assays run in parallel resulted in a 4-58% increase in recognition of CVBD exposure or infection.
We conclude that serological and PCR assays should be used in parallel to maximize CVBD diagnosis.
Keywords: Vector-borne canine diseases, Serology, Molecular tests, Diagnostic panel