Accuplex study highlights option for canine tick-borne screening

A JAVMA report is putting fresh attention on canine tick-borne disease screening, concluding that the silicon surface multiplex immunoassay Accuplex is a robust option for detecting antibodies to Anaplasma spp. and Ehrlichia spp. in dogs. The study compared the reference-lab assay from Antech Diagnostics with IDEXX’s SNAP 4Dx Plus point-of-care test, using indirect fluorescent antibody testing as the reference method, and also assessed how Accuplex findings aligned with broader prevalence patterns reported by the Companion Animal Parasite Council, or CAPC. (2025acvimforum.eventscribe.net)

The backdrop is a diagnostic landscape that has become more complicated as tick-borne pathogens spread into new areas and as clinicians rely on both in-house screening and reference-lab testing to guide next steps. CAPC says its annual ehrlichiosis and anaplasmosis forecasts are built to predict what veterinarians and laboratories will find in dogs, and its maps are meant to support conversations about local risk, travel exposure, and prevention. CAPC also stresses an important limitation: antibody-based maps estimate the probability of a dog testing positive for current or past infection, not active disease by itself. (capcvet.org)

That distinction is central to how this study lands in practice. According to Antech, Accuplex is designed to detect antibodies to three Ehrlichia species and two Anaplasma species in dogs, alongside Lyme and heartworm targets on the broader panel. IDEXX similarly frames positive Ehrlichia results on SNAP 4Dx Plus as evidence of tick exposure and transmission of infectious agents, while recommending additional testing to determine whether active infection is present. In other words, better screening sensitivity or broader species coverage can improve case finding, but it doesn’t eliminate the need for clinical interpretation. (antechdiagnostics.com)

There’s also some context from prior work. An ACVIM Forum abstract describing field validation of updated Anaplasma and Ehrlichia peptides on the Accuplex platform reported that the assay detected higher tick-borne pathogen antibody rates in dogs than those reported through CAPC. Meanwhile, earlier published studies have shown continued efforts by IDEXX to improve acute-phase detection of Anaplasma and Ehrlichia antibodies on SNAP 4Dx Plus. Together, that suggests an active competition around assay design, peptide selection, and how well screening tools capture real-world exposure across regions with shifting tick ecology. (2025acvimforum.eventscribe.net)

Industry guidance around the assays also hints at how veterinarians may operationalize results. Antech’s Accuplex FAQ says a negative result does not fully close the book when clinical suspicion remains high, noting that if signs or lab findings still suggest ehrlichiosis, IFA or PCR should be considered. CAPC’s guidance is consistent on the prevention side, recommending year-round tick control because tick activity can occur throughout the year and pets may travel into endemic areas. CAPC also highlights the public health dimension: several Ehrlichia and Anaplasma species affecting pets are established zoonotic agents, and dogs can function as sentinels for human exposure risk. (antechdiagnostics.com)

Why it matters: For veterinary professionals, this is less a story about one test “winning” than about sharpening surveillance and interpretation. A robust multiplex assay could help clinics identify more dogs with prior or current exposure, especially in regions where pathogen risk is changing or where travel history muddies the picture. But positive serology still has to be integrated with platelet counts, chemistry changes, urinalysis, clinical signs, and, when needed, PCR or paired testing. That’s especially relevant because CAPC’s own materials emphasize that prevalence maps are educational and population-level tools, not direct measures of active disease burden in an individual patient. (capcvet.org)

The study also matters because canine screening data increasingly does double duty. It informs patient care, but it also feeds the broader surveillance picture that veterinarians use to counsel pet parents about prevention. CAPC says its forecast models have historically been more than 94% accurate in estimating true prevalence for the major diseases it tracks, and its 2026 forecast continues to warn that vector ranges and associated pathogen risks are expanding. For clinics, that means screening strategy, preventive recommendations, and client education are becoming more closely linked. (capcvet.org)

What to watch: The next step is whether the full JAVMA paper changes how practices balance in-house screening with reference-lab multiplex testing, and whether future guidance clarifies where Accuplex is most useful in annual screening, confirmatory workups, and regional disease surveillance. (antechdiagnostics.com)