Grade A Eggs as a Source of Salmonella enteritidis Infections-Reply

Abstract

In Reply.— Mr Thomas evidently misunderstood the epidemiologic methods that were the core of our report. We did not interview persons 1 or 2 years after their illness. Rather, state and local health departments routinely investigate food-borne disease outbreaks at the time of occurrence, recording specific epidemiologic data such as food-specific attack rates and microbiological tests of foods. The epidemiologic findings we reported from 1985 through 1987 therefore represented an analysis of the aggregate results from an extensive series of independent investigations of food-borne disease outbreaks reported to the Centers for Disease Control. Our ability to collect and analyze 65 S enteritidis outbreaks occurring in the northeastern United States testifies to the extraordinary rise of this one serotype of Salmonella as an agent of food-borne disease in recent years. Grade A eggs or foods containing such eggs were implicated in 77% of these S enteritidis outbreaks in which the vehicle