Here I recount my research journey on the coccidian protist Toxoplasma gondii (Nicolle et Manceaux, 1908), a ubiquitous parasite capable of infecting all warm-blooded animals as intermediate or secondary host, but with only members of the Felidae as its definitive host. I describe my initial studies into its epidemiology and persistence within the UK, and how this led on to a series of biologically and ethically appropriate studies into T. gondii's apparent specific manipulation of its rat intermediate host to facilitate transmission to its feline definitive host. I then describe how this prompted searches into the potential mechanisms of action behind such manipulation and what this raises in terms of behavioural changes, from the subtle to severe, across other secondary hosts including humans.

Department of Pathobiology and Population Sciences Royal Veterinary College University of London Herts United Kingdom

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