To describe dogs with detected Ancylostoma caninum anthelmintic treatment resistance markers in Canada.
11 client-owned dogs with fecal quantitative PCR (qPCR) assay detected A caninum with benzimidazole (BZ) resistance genotypic markers.
Signalment, presenting concern, duration of clinical signs, fecal testing, treatment, and outcomes were obtained. Where available, follow-up data were collected via telephone or email with the primary veterinarian.
Ancylostoma spp was detected from 184/32,205 dog fecal samples by reference laboratory qPCR surveillance, between May 15, 2022, and April 26, 2023. 11 of these 184 samples had A caninum with genetic BZ F167Y resistance marker detection. 4 dogs had not traveled outside Canada, 6 had been imported from the US, and the travel history was unclear in 1 dog.
7 of the dogs had gastro-intestinal signs (diarrhea or soft stool) on initial presentation. Clinical improvement was reported in 6 of these dogs (resolution of diarrhea and soft stool), with 1 dog lost to follow-up. All 11 dogs received anthelmintic treatment (varied drugs and duration).
Identification of genetic markers of BZ resistance raises concerns about the potential animal and human impacts of resistant hookworms. 4 dogs lacked an origin from or travel history to the US, indicating true emergence and/or novel spread within Canada, not just importation from an area where resistance has been reported. Fecal surveillance was performed with a qPCR test incorporating treatment (BZ) resistance markers. There is a need to raise clinician awareness around treatment-resistant hookworm in dogs and the capability of fecal surveillance for genotypic and phenotypic resistance.
To describe the novel PCR diagnosis and outcome of intestinal Echinococcus multilocularis in a dog.
A 13-month-old female intact dog with naturally occurring intestinal E multilocularis.
CLINICAL PRESENTATION, PROGRESSION, AND PROCEDURES
The 13-month-old dog initially presented with a reduced appetite and weight loss and then developed hematochezia. The clinical history included a lack of endoparasite preventive care (fecal testing, deworming), exposure to coyotes, fox, sheep, and rodents and the dog had intermittently been fed a raw food diet. Physical examination revealed a thin dog, with a 2/9 body condition score, that was otherwise clinically unremarkable. A fecal sample was submitted for screening for gastrointestinal parasites as part of an infectious disease assessment. The fecal PCR test reported detection of E multilocularis. This result was sequenced as the European haplotype E3/E4. Centrifugal flotation (same sample) did not detect taeniid eggs.
TREATMENT AND OUTCOME
The dog was treated with metronidazole, maropitant, and milbemycin oxime/praziquantel. Clinical improvement was noted within 48 hours. No DNA of E multilocularis was detected in a fecal sample collected approximately 10 days after treatment. The dog’s owner was advised to provide monthly deworming (praziquantel) for all dogs on the property and to contact their human health-care provider due to potential zoonotic exposure risk.
Increasing detection of E multilocularis is occurring in dogs in Canada and the US. Alveolar echinococcosis can cause severe disease in dogs and humans. Fecal PCR detection and surveillance may alert practitioners to canine intestinal cases and allow dogs to serve as sentinels for human exposure risk.