Salmonella-infected eggs traceable to a large egg producer in Iowa may have caused as many as 1,200 cases of intestinal illness in at least 10 states in recent weeks, according to an investigation by state and federal epidemiologists.
Wright County Egg has voluntarily recalled 380 million eggs, some laid as long ago as May 17. The vast majority have already been consumed. The eggs went to distribution companies in 17 states, mostly west of the Mississippi River, but were then sold nationwide.
State and local health departments, assisted by the Centers for Disease Control and Prevention, are studying cases of salmonella illness in Arizona, Connecticut, Massachusetts, Maryland, North Carolina, Nevada, Oregon, Pennsylvania, Tennessee and Texas, according to the Food and Drug Administration. Officials at the Maryland Department of Health and Mental Hygiene, however, said they know of no cases appearing to be linked to the Iowa eggs.
While the sale of fresh eggs from Wright County Egg is stopped for the moment, the number of illnesses is expected to rise in the next few weeks as previous cases come to the attention of the health authorities and some new infections occur.
Tests of the company's hen houses and eggs, which are produced at five farms in the central Iowa towns of Galt and Clarion, are not yet complete, an FDA official said Thursday. Eggs can become infected by the salmonella bacterium by being laid by infected hens, or by contamination during storage or packaging.
Ironically, the outbreak occurred just as new federal regulations designed to prevent salmonella contamination of eggs took effect on July 9.
The rules, under development since 2004, require egg farms of a certain size to test for "environmental contamination" by salmonella bacteria, which is carried in the feces of many species; limit access to chicken houses; control rodents, which can contaminate chicken feed with feces; clean and disinfect poultry houses under certain circumstances, and hold and transport eggs at a cool temperature.
Many states, as well as egg-producer associations, have voluntary "egg quality assurance" programs with guidelines similar to those that are now mandatory. A spokeswoman for Wright County Egg, Hinda Mitchell, said the company has voluntarily followed the new rules "for several years."
However, in a telephone briefing, Sherri McGarry, of the FDA's Center for Food Safety and Applied Nutrition, Sherri McGarry, told reporters, "We do believe that the outbreak could have been prevented."
The bacterium causes nausea, vomiting and fever. In healthy people it rarely causes severe illness. In people with weak immune system - and especially in AIDS patients - salmonella can cause life-threatening bloodstream, blood vessel, or brain infections. In 2004, there were about 1.4 million salmonella infections from all causes (not just food consumption), with 14,264 hospitalizations and 427 deaths.
The cases found so far have been in people who became ill after eating eggs at restaurants, said Christopher Braden, the head of CDC's division of foodborne diseases. Among the earlier states to investigate such multiple-victim outbreaks were Minnesota, California and Colorado.
There are almost certainly many "sporadic" cases - single illnesses in people who ate eggs at home - that have not been reported and probably never will be. There have been no reports of death, he added, although it is likely some people have required hospital stays.
"I think we'll probably get reports of a significant number more cases," Braden said.
While some of the restaurant-linked cases occurred as long ago as May, the realization there was a national outbreak under way didn't become clear until mid-July, said McGarry, the FDA official. The egg products consumed in different restaurants were not the same.
The company said its eggs covered by the expanded recall this week are packaged under the following brand names: Albertsons, Farm Fresh, James Farms, Glenview, Mountain Dairy, Ralphs, Boomsma, Lund, Kemps and Pacific Coast. The earlier recall was for eggs sold under the brands Lucerne, Albertson, Mountain Dairy, Ralphs, Boomsma's, Sunshine, Hillandale, Trafficanda, Farm Fresh, Shoreland, Lund, Dutch Farms and Kemps.
Details about how to identify the recalled eggs are at fda.gov/safety/recalls/ucm223139.htm.