Abstract
Disability Adjusted Life Years (DALYs) are good estimates of the effects caused by waterborne pathogens in drinking water. The illness-to-infection rate of Campylobacter jejuni is one of the most important factors for estimating DALYs. In this study, the illness-to-infection rate of Campylobacter jejuni was estimated on the basis of seroepidemiological survey. From the data of serum antibody levels against C. jejuni, the cutoff levels for asymptomatic infection were set on the basis of medical data from previous studies and using a statistical procedure. From these cutoff levels, the percentage of people with asymptomatic infection was estimated to be 7.9 - 35.0% and 12.1 - 13.6%, respectively. By using the numbers of people with symptomatic infection estimated using the number of laboratory-confirmed cases, the illness-to-infection rate of C. jejuni was estimated to be 12.1 - 53.8% and 31.3 - 35.1%, respectively.
