Global emergence of Rickettsia felis infections: the hidden threat in pets and their fleas
Lucas G. Huggins A * and Vito Colella AA
Dr Lucas Huggins is a postdoctoral research fellow specialising in molecular techniques at The University of Melbourne Veterinary School. His current research focus is on the development of pan-pathogen molecular tools for humans and animals of veterinary importance that can aid us in understanding parasite diversity and epidemiology, particularly in some of the most neglected regions of the world. |
Dr Vito Colella is a senior research fellow and senior lecturer in the Department of Veterinary Biosciences at The University of Melbourne. His current research focuses on the development of novel diagnostics for neglected tropical diseases and intervention strategies to mitigate the impact of zoonotic parasites on animal and human populations in the Asia-Pacific region. |
Abstract
The globally emerging pathogen Rickettsia felis uses the cat flea as a biological vector and can cause serious infections in humans. Rickettsia felis can be transmitted to numerous mammalian hosts, but to date, only dogs have been demonstrated as an amplifier host that is infectious to naïve cat fleas. When infected, canines typically do not show clinical signs making them ideal pathogen reservoirs through which fleas can silently transmit R. felis from pets to co-habiting humans. Once infected, humans develop the multi-systemic disease flea-borne spotted fever with symptoms ranging from mild fevers, rashes and muscle aches through to severe disease. Given the close associations between fleas, pets and humans, it is not surprising that serosurveys of R. felis in people have found high levels of exposure, particularly in at-risk demographics, such as veterinarians. Nonetheless, although sensitive diagnostic tools for the detection of R. felis exist, a deep understanding of R. felis epidemiology and transmission remains lacking. A greater research focus must be placed on using such diagnostic tools to resolve outstanding questions surrounding R. felis pathophysiology and biology, including the role of companion animals in pathogen transmission.
Keywords: canine, companion animals, Ctenocephalides felis, domestic dog, flea-borne spotted fever, metabarcoding, rickettsiosis, zoonosis.
Dr Lucas Huggins is a postdoctoral research fellow specialising in molecular techniques at The University of Melbourne Veterinary School. His current research focus is on the development of pan-pathogen molecular tools for humans and animals of veterinary importance that can aid us in understanding parasite diversity and epidemiology, particularly in some of the most neglected regions of the world. |
Dr Vito Colella is a senior research fellow and senior lecturer in the Department of Veterinary Biosciences at The University of Melbourne. His current research focuses on the development of novel diagnostics for neglected tropical diseases and intervention strategies to mitigate the impact of zoonotic parasites on animal and human populations in the Asia-Pacific region. |
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