The Colonisation Potential of Campylobacter jejuni Strain 81116 Is Enhanced after Passage through Chickens

Abstract

Although the sources and routes of transmission of human Campylobacter jejuni infections are not yet understood, there is strong circumstantial evidence to implicate poultry as one major source; transmission being either directly through consumption of undercooked chicken or by cross-contamination of other foods in the kitchen¹. In Great Britain about 50% of broiler flocks are colonised by campylobacters (Evans, S., personal communication). An understanding of the epidemiology of campylobacters in these infected flocks is considered essential for the development of successful intervention regimens. To date the sources of infection and routes of transmission within a poultry flock are poorly investigated. In broiler houses the birds usually remain uninfected until 2–3 weeks of age, but then infection spreads rapidly through the flock (reviewed by Stern³). Recent establishment of chicken experimental models has allowed the minimal oral dose of C.jejuni strain 81116 to be determined⁴. Given this dose, the relatively slow growth rate and fragility of the organism in vitro and the constricted movement of chickens within broiler houses, such a rapid spread via the faecal-oral transmission route is questionable. However, laboratory adaptation and the human source² of C.jejuni strain 81116 may have affected its potential to colonise this chicken model.