My experience with a peer that deeply affected me

A casual phone call in September 1989 changed my life dramatically. It was from a Townsville gastroenterologist John Croese, asking if I’d heard of eosinophilic enteritis (EE), and whether infection with a canine hookworm, Ancylostoma caninum, could be a cause in humans.

I was, at that very point, in the process of expediting my return to the clinical world, having elucidated a fascinating parasite life-cycle (of Toxocara pteropodis, a nematode in Flying Foxes), explained the cause of the Palm Island “mystery disease” (copper sulphate poisoning), and been awarded my PhD and gained academic promotion.

The interlude from clinical life had turned out far more protracted than originally planned, and I’d never intended to become an academic, but John Croese's query, and its underlying rationale, proved tantalisingly irresistible.

While accepting that some zoonotic parasite was the most likely agent in the EE epidemic he’d been documenting in northern Queensland, I doubted the dog hookworm was involved. He arranged for me to visit Townsville and meet various clinicians, followed up by detailed field investigations of many of his patients.

Our initial findings changed my scepticism, sealed by his recovery of a hookworm at colonoscopy from a typical patient (case report published in The Lancet). This experience compelled me to stay in the academic world, opening up a multitude of investigations into hookworm and other infections, thus directing the rest of my working life, including research projects and collaborations.

It also triggered John’s investigations of parasites as potential immunological modulators in the pathogenesis of IBD.