Two people have died and 58 have become ill in the US and Canada over the past seven weeks from E. coli bacteria likely found in romaine lettuce. Food safety experts are urging consumers to choose a substitute vegetable.
The bacteria has been identified as E. coli O157, a strain which can be deadly for the elderly, infants, pregnant women and people with weak immune systems.
Cases have been documented in California, Connecticut, Illinois, Indiana, Michigan, Nebraska, New Hampshire, New York, Ohio, Pennsylvania, Virginia, Vermont, and Washington state. Canada is investigating 41 cases in the provinces of Ontario, Quebec, New Brunswick, Nova Scotia, Newfoundland and Labrador.
“The Public Health Agency of Canada has identified romaine lettuce as the source of the outbreak in Canada,” the Centers for Disease Control (CDC) said in a statement. The CDC investigation in the US has yet to conclude. However, several of the US cases were determined to have been caused by genetically similar bacterium.
“Based on the Canada investigation, romaine lettuce seems like the most likely source there,” said Ian Williams, chief of the CDC's Outbreak Response and Prevention Branch, according to CNN. “We're very hopeful that things are wrapping up, but we don't have enough data to say that.”
While Canadian officials have identified lettuce as the culprit, they have yet to figure out which brands consumers should avoid.
"Unfortunately, we have not been able to find common lettuce brands or common stores," Williams said. "The trace-back information is always challenging too, because contamination can happen any place from the farm to the processing facility to the store.”
It is virtually impossible for consumers to know if they are consuming E. coli because it is invisible, odorless and tasteless. People infected with E. coli can suffer from a wide range of symptoms. Some may experience minor effects such as an upset stomach, while others may become extremely ill and require hospitalization. Symptoms may appear within one to ten days of contact with the bacteria, including nausea, vomiting, headache, mild fever, severe stomach cramps and watery or bloody diarrhea.
There is no treatment for E. coli infections beyond preventing dehydration through proper water intake and nutrition. Even washing the lettuce does not help.
"This bacteria can actually get inside the lettuce leaf," Williams said. "Washing it doesn't make it safe."