Household flea infestations and the risk to the immune suppressed

Household flea infestations and the risk to the immune suppressed

While much focus has been placed on the role of ticks in zoonotic pathogen transmission, fleas in the UK have been largely overlooked as vectors of zoonotic disease. The Big Flea Project, surveying flea infestations on UK cats and dogs, found fleas to be infected with both Bartonella and Rickettsia felis, both of particular concern as a cause of disease in the immune suppressed. Bartonella spp. infections are common in domestic cats and transmission is thought to arise primarily from infected fleas. Bartonellosis is a significant zoonosis with a variety of clinical presentations and can be fatal in the immune suppressed. Similarly, Rickettsia felis is flea transmitted and is an underdiagnosed cause of fever and lethargy in humans. It can also be a source of chronic debilitating disease in the immune suppressed. This article discusses Bartonella and Rickettsia felis infection in UK fleas, human infection and measures that can be taken to limit zoonotic risk while maintaining the human-animal bond.