The Centers for Disease Control and Prevention said Friday it has yet to determine the source of an E. coli outbreak that has infected 72 people in five states — an admission one expert in foodborne illness called “perplexing,” considering how many have fallen victim to the illness.
The recent spate of sickness, which began March 2, is directly linked to a strain of E. coli known as "O103,″ according to the CDC. Eight people have been hospitalized as a result of the O103 outbreak, however, no deaths have been reported. The patients ages range from 1 to 74 years old with a median age of 17.
Symptoms of E. coli infection often include severe stomach cramps, diarrhea and vomiting, typically occurring three days after consuming the bacteria. The states affected by the outbreak are Ohio, Virginia, Kentucky, Tennessee and Georgia.
Bill Marler, a food safety lawyer from Seattle with more than 25 years of experience, told The Post there's "no question" the patients in this case share one common source of infection. It's "concerning," he said, that the CDC has yet to pinpoint the source to a specific food item, grocery store or restaurant chain.
"Given the size and the number of states that are involved, what you're seeing is very unusual," Marler said. "If it was five people or 10 people, that's a little harder to figure out. But when there's 72 people and they're being interviewed by epidemiologists, it's pretty unusual you don't have a culprit."
He added: "The real question is, what do 72 people have in common over five states? It has to be something."
That something, Marler said, is likely a food or water product that people can't remember they ate. State and local health officials are required to interview ill patients and determine what they consumed in the week leading up to their symptoms, but recalling one's dietary choices is oftentimes easier said than done, he said.
Condiments, garnish, toppings, and spices can all contain traces of E. coli. But it's unlikely the patients in this outbreak were keeping track of all the additives in their recent diets, he added.
“That’s probably why it’s taking longer to figure out — because people can’t remember what was in their meal,” Marler said.
Citing a CDC data set that dates back to 1998, Marler noted outbreaks of E. coli O103 are relatively uncommon. Eighteen such cases have been reported in the United States since 2000, with the highest number of reported illnesses being 29 during a 2010 outbreak in Minnesota.
That makes this O103 outbreak by far the largest in recent memory, he said.
It's likely that number will grow. Marler said the CDC estimates that for every person reported sick, there are 5 to 10 ill people who have not been accounted for. "I would expect to see the numbers at least double in the next 10 days unless immediate action is taken this weekend," he said.
Thirty-six of the reported illnesses in this case stem from Kentucky. Last week, local health officials issued an alert for a "sudden increase in O103 cases" in the state, according to the Mercer County Health Department, which wrote in a Facebook post the illnesses were found in "children and teenagers with extensive exposure to fast food."
If that's true, Marler said, it corresponds the dietary habits of many 17-year-olds: the reported median patient age.
"It definitely does underscore it's probably some convenience, fast food consumed by kids," he said. One silver lining, he added, is that people in this age range are typically healthy and not prone to further complications from E. coli.
To avoid disease, the CDC advises that people cook foods thoroughly, wash fruits and vegetables and limit consumption of raw or unpasteurized juice and dairy products. Hand washing can also help prevent contamination.
But Marler says people fearing illness should go one step further: avoid uncooked food items entirely, at least until the CDC draws its conclusion.
"It won't kill you not to have a salad or smoothie made with fresh fruits and vegetables," Marler said. "You can live without that for a couple days as this shapes out."
- - -
The Washington Post’s Lena H. Sun contributed to this report.