Nothrus mite as a potential cause of exacerbation of pruritus in a cat

Abstract

Objectives Morphological and molecular approaches were used to identify arthropods associated with feline pruritus. The literature associated with the arthropod genus identified was reviewed. Methods On two occasions (summer 2020 and summer 2021), the owner of a cat with seasonal pruritus (commenced 2020) found the cat’s bed was substantially infested with arthropods suspected of being associated with exacerbated pruritus. The pruritus was largely itching and hair loss, particularly on the abdomen, and flaking skin patches. On the second occasion (2021), examples of the arthropods were sent to the parasitology laboratory at the Norwegian University of Life Sciences for identification. They were examined by stereomicroscopy and tentatively identified based on morphology. DNA was extracted, and identification confirmed by PCR and sequencing. The literature was reviewed to determine whether this arthropod genus has previously been considered to be associated with pruritus or the infestation of mammals. Results Based on morphological characteristics, the arthropods were tentatively identified as Nothrus species mites. This was confirmed by PCR. A literature review found no previous reports of pruritus or other clinical signs associated with Nothrus species mites, and mites were not found on the cat. However, this mite has previously been found on small mammals at densities exceeding that expected of incidental stragglers. Conclusions and relevance The large number of Nothrus species mites could have exacerbated the cat’s pruritus. By publishing this study, we hope to alert veterinarians to the possibility that Nothrus species mites may cause or exacerbate pruritus in cats.