Federal and local health officials continue to monitor the conditions of four U.S. travelers who developed complications from a rare strain of E. coli they apparently contracted last month during visits to Germany.
Three of the patients have been hospitalized with Hemolytic-uremic syndrome (HUS), an infection of the digestive system that can cause kidney failure and, in the most severe cases, brain damage and seizures.
Federal health officials are also monitoring potential, but still unconfirmed, cases of E. coli infection in two members of the U.S. military serving in Germany.
"We expect to see a few more cases among travelers, unfortunately," said Robert Tauxe, MD, deputy director of the Division of Foodborne, Bacterial and Mycotic Diseases at the Centers for Disease Control and Prevention in Atlanta.
"We think the risk of it spreading to other people in the United States is low. The main problem with this infection is going to be from eating contaminated food. And we're not aware that any of the suspect foods have been brought to the United States."
According to the U.S. Food and Drug Administration, the U.S. receives relatively little fresh produce from Europe. However, the FDA has stepped up surveillance and targeted inspections of agricultural products from Germany as a precaution.
"There is no reason for Americans to alter where they shop, what they buy or what they eat," said David Elder, director of the FDA Office of Regional Operations. German health officials have yet to determine the exact source of the E. coli outbreak that has now claimed at least 18 lives and sickened more than 1,800 people.
But they have found a close association between the outbreak and raw salad produce grown in the northern part of that country.
Tauxe said U.S. travelers to Germany need not cancel their plans, but should heed warnings from local authorities to avoid eating cucumbers, lettuce and tomatoes from northern Germany.