(AP) -- Hundreds of people have been sickened in a salmonella outbreak linked to eggs in four states and possibly more, health officials said Wednesday as a company dramatically expanded a recall to 380 million eggs.
The Centers for Disease Control and Prevention is working with state health departments to investigate the illnesses. No deaths have been reported, said Dr. Christopher Braden, a CDC epidemiologist involved in the investigation.
Initially, 228 million eggs, or the equivalent of 19 million dozen-egg cartons, were recalled by the company Wright County Egg of Galt, Iowa. But that number was increased to nearly 32 million dozen-egg cartons.
Minnesota, a state with some of the best food-borne illness investigators in the country, has tied at least seven salmonella illnesses to the eggs.
Other states have seen a jump in reports of the type of salmonella. For example, California has reported 266 illnesses since June and believes many are related to the eggs. Colorado saw 28 cases in June and July, about four times the usual number. Spikes or clusters of suspicious cases have also been reported in Arizona, Illinois, Nevada, North Carolina, Texas and Wisconsin.
Salmonella is the most common bacterial form of food poisoning. And the strain involved in the outbreak is the most common strain of salmonella, accounting for roughly 20 percent of all salmonella food poisonings.
Unfortunately, current lab tests do not allow health officials to fingerprint this form of salmonella as precisely as other kinds of food-borne illness. So determining the size of a salmonella enteritidis outbreak is a little more challenging, Braden said.
The Food and Drug Administration also is investigating.
Much of the investigation so far has been centered on restaurants in California, Colorado, Minnesota and North Carolina. They are not necessarily breakfast places - it's possible some got sick from eating a salad dressing that had a raw egg in it, or eating soup with an undercooked egg dropped in, Braden said.
In North Carolina, a cluster of about 80 illnesses in April were linked to meringue-containing chocolate pie and banana pudding served at a Durham barbecue restaurant, health officials said.
Eggs from Wright County Egg were linked to illnesses in the four states. The eggs were distributed around the country and packaged under the names Lucerne, Albertson, Mountain Dairy, Ralph's, Boomsma's, Sunshine, Hillandale, Trafficanda, Farm Fresh, Shoreland, Lund, Dutch Farms and Kemp. It wasn't immediately clear when the eggs were produced and distributed.
The initial recall was issued last week. Eggs affected by the expanded recall were distributed to food wholesalers, distribution centers and food service companies in California, Colorado, Minnesota, Arkansas, Arizona, Georgia, Illinois, Iowa, Oklahoma, Oregon, Missouri, Nebraska, Nevada, Texas, Utah, Washington and Wisconsin.
"We are undertaking this additional recall to further protect the safety of consumers - this voluntary measure is consistent with our commitment to egg safety, and it is our responsibility," Wright County Egg officials said in a statement Wednesday evening.
In an earlier statement, company officials said the FDA is "on-site to review records and inspect our barns." The officials said they began the recall Aug. 13.
The most common symptoms of salmonella are diarrhea, abdominal cramps and fever within eight hours to 72 hours of eating a contaminated product. It can be life-threatening, especially to those with weakened immune systems.
This form of salmonella can be passed from chickens that appear healthy. And it grows inside eggs, not just on the shell, Braden noted.
Thoroughly cooking eggs can kill the bacteria. But health officials are recommending people throw away or return the recalled eggs.
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More information: Centers for Disease Control: http://www.cdc.gov/salmonella/enteritidis
Egg Safety Center: http://www.eggsafety.org