Fleas infesting cats and dogs in Great Britain and the Isle of Man
: the drivers of infestation risk.

  • Amber-Rose Cooper

Student thesis: Master's ThesisMaster of Science (MSc)


Fleas are the most abundant and clinically important ectoparasite infesting domestic cats and dogs. In addition to the irritation, blood loss and transmission of infectious disease associated with biting, blood-feeding may trigger a severe allergic dermatitis in sensitised hosts. Here, the spatial pattern of flea infestation risk across Great Britain is considered using data collected from a national survey undertaken in 2018, with particular attention given to the effects of insecticide use on infestation risk. The data show a statistically significant geographical pattern, with flea infestation risk declining from south to north. None of the factors: pet breed, sex, neutered status, or outdoor access, showed any relationship with the underlying geographic distribution of flea infestation which therefore is most likely to be associated with climatic factors. However, overall, only 23.6% of the cats and 35% of the dogs inspected had been treated with identifiable flea products that were still ‘in date’ at the point of inspection. The percentage of owners treating their pet broadly followed that of infestation risk. The insecticide Fipronil, a common active in a wide range of flea treatments, was the commonest insecticide class applied to cats. However, 62% of cats and 45% of dogs that had been treated with a fipronil-based product that was in-date at the point of inspection still had fleas. Persistent flea infestation is likely to be due to a range of factors, including compliance and application failure, but the data presented here provide strong inferential evidence for a lack of efficacy of fipronil-based products indicating a need to monitor emerging resistance to on-host flea treatments. Given the ubiquity of flea infestation, this finding and the relatively low-level treatment compliance, highlight a clear need for greater owner education about the importance of flea management and the efficacy of different product types.
Date of Award26 Nov 2020
Original languageEnglish
Awarding Institution
  • The University of Bristol
SupervisorRichard Wall (Supervisor) & Bryony Sands (Supervisor)

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