By Harold McGee
Beginning around 1985, a hitherto minor bacterium called Salmonella enteritidis was identified as the culprit in growing numbers of food poisonings in continental Europe, Scandinavia, Great Britain, and North America. Salmonella can cause diarrhea or more serious chronic infection of other body organs. Most of these outbreaks were associated with the consumption of raw or lightly cooked eggs. Further investigation demonstrated that even intact, clean, Grade A eggs can harbor large numbers of salmonella. In the early 1990s, U.S. health authorities estimated that perhaps one egg in 10,000 carried this particularly virulent form of salmonella. Thanks to a variety of preventive measures, the prevalence of contaminated eggs is now much lower—but it’s not zero.