(CNN) -- Health officials are working to find the source of an E. coli outbreak that has sickened 17 individuals in seven states over the past four weeks. Six of those infected have been hospitalized.
"The investigation is still ongoing and a specific food item, grocery store, or restaurant chain has not been identified as the source of infections," the US Centers for Disease Control and Prevention said in an outbreak investigation announcement Tuesday.
New Jersey has reported six cases, Idaho has reported four cases, Pennsylvania and Connecticut have each reported two cases, and Washington, Missouri and Ohio have each reported one illness.
Those who are ill began experiencing symptoms between March 22 and 31. They range in age from 12 to 84, and the majority of patients, 65%, are female.
Symptoms of E. coli typically begin two to eight days after consuming the bacteria. They include severe stomach cramps, diarrhea and vomiting. Most people recover in five to seven days. Some individuals may develop a severe illness called hemolytic uremic syndrome, which can be life-threatening, although most people recover in a few weeks. Those most at risk for E. coli illness include the very young, the very old and individuals with compromised immune systems.
No deaths have been reported from this outbreak, although one of the hospitalized patients developed hemolytic uremic syndrome.
"State and local public health officials are interviewing ill people to determine what they ate and other exposures in the week before their illness started," the CDC said.
The CDC and the US Food and Drug Administration are working with state and local health officials to identify the source of the outbreak.