Salmonella Enteritidis; from the Chicken to the Egg
Blumenthal, Dale, FDA Consumer
White, shining, unmarred-a Grade A mystery now lies in the uncracked egg. Is it safe to eat?-9,999 times out of 10,000, yes. But ...
In May 1989, six nursing home patients in Pennsylvania died from Salmonella enteritidis poisoning after eating stuffing that contained undercooked eggs.
In July, 21 guests at a baby shower in New York became ill after eating a pasta dish made with a raw egg. One victim was 38 weeks pregnant and delivered her baby while ill. The newborn infant developed Salmonella enteritidis blood poisoning and required lengthy hospitalization.
Last August, a healthy 40-year-old man died, and 14 others were hospitalized, after eating egg-based custard pie contaminated with Salmonella enteritidis, which was served at a company party in Pennsylvania. The list goes on.
Public health officials are concerned. More than 49 outbreaks of Salmonella enteritidis poisoning took place in nine states and Puerto Rico last year, resulting in at least 13 deaths and more than 1,628 illnesses. According to the Jan. 5, 1990, issue of the Centers for Disease Control's Morbidity and Mortality Weekly Report, from January 1985 through October 1989, 189 Salmonella enteritidis outbreaks in the United States caused 6,604 illnesses and 43 deaths. Many more illnesses probably went unreported, says Joseph Madden, Ph.D., deputy director of FDA's division of microbiology.
Health investigators suspect that contaminated shell eggs caused nearly half of these outbreaks. The egg connection in these cases was determined by tracing the food eaten by the victims and taking cultures both from patients and foods.
Especially at risk for Salmonella poisoning are the elderly, the very young, pregnant women (because of risk to the fetus), and people already debilitated by serious illness, malnutrition, or weakened immune systems. Symptoms of Salmonella enteritidis infection usually include diarrhea, vomiting, abdominal pain, chills, fever, and headache. The bacteria can invade organs outside the gastrointestinal tract, causing complications that require lengthy hospitalization, even in healthy people.
Symptoms usually develop 12 to 36 hours after eating the contaminated food. The initial illness also can bring about serious chronic complications.
In 1985, in an incident in Chicago, more than 16,000 people contracted food poisoning from low-fat milk contaminated with Salmonella bacteria. Within two weeks, about 2 percent of these patients developed a chronic reactive arthritis condition linked to the infection. Although the Salmonella bacteria that made these people ill was not Salmonella enteritidis, researchers have found that rats infected with Salmonella enteritidis may develop the same arthritic condition. Researchers are concerned that Salmonella enteritidis may also cause this complication in humans.
Since 1976, says Robert Tauxe, M.D., a CDC expert on the spread of the disease, the reported rate for Salmonella enteritidis infections from food "has increased more than sixfold in the northeastern part of the United States." First noted in the New England states, the infections also appeared in the mid-Atlantic region by 1983, and now have become a problem in the south Atlantic states as well. Recently, outbreaks were reported in Minnesota, Ohio and Nevada.
The problem also has become an international egg to crack. "The U.S. Salmonella epidemic," says Tauxe, "is dwarfed by dramatic increases that have been reported from Yugoslavia, Finland, Sweden, Norway, and the United Kingdom." In Britain alone, the number of confirmed Salmonella enteritidis cases reported for January through July 1988 (4,424 cases) was more than double the number (2,000) for the same period in 1987.
Source: Intact Eggs
At first, says Tauxe, "we did not have an explanation for this striking increase." The first real clue that intact eggs were a source of the problem came in 1983, when CDC traced a large outbreak caused by Salmonella enteritidis to a commercial stuffed pasta product made with raw eggs. …