Research Update CHF 03169 MY1: Characterization of hookworm resistance in dogs with a novel diagnostic test for early intervention

The dog hookworm, Ancylostoma caninum, is the most common worm parasite of dogs in the United States. It is specific to dogs but can infect humans by entering through intact skin (zoonotic), causing cutaneous larval migrans, a painful skin condition. Treatment options in dogs include the benzimidazole (BZ) drugs. However, hookworms have recently developed resistance to BZs. This resistance has been associated with two mutations – F167Y and Q134H in a gene of the worm. We have developed a PCR to test for these two mutations in the feces of infected dogs. The PCR test tells us if the mutations causing resistance is present in the sample or not, and also at what level the mutation is present. We have currently tested the PCR on the feces of 75 dogs from the mid-western United States.

Interestingly, we found that on average 50.9% of the hookworm infected dogs that we have tested so far had hookworms that had the resistant gene. However, the amount of resistance in the samples ranged from 1% to 100%. Approximately 41% of the samples have very high resistance levels (>75% resistant gene). Knowing this information is very useful for veterinarians to make a decision on which dewormer to prescribe. Thus, by detecting resistance early in hookworms from individual dogs using this qPCR test, we are helping both veterinarians and owners avoid treatments that may not work. We are in the process of validating these results further with next generation sequencing. The results from this study have implications for parasite control measures implemented by pet owners and veterinarians.

Mid-Year-1 03169 Research Update Hookworm Resistance in Dogs