A multi-state cluster of at least 10 people infected with E. coli bacteria has been identified and public health officials are interviewing victims about possible foodborne sources.

As of this afternoon, patients had been identified in four states, said a spokeswoman with the Centers for Disease Control and Prevention.

“This investigation is ongoing, and we will updat the public when more information becomes available,” she said. “CDC and state and local public health partners are continuing laboratory surveillance through PulseNet to identify additional ill people and to interview those people about foods they ate before they got sick.”

With the PulseNet database of DNA patterns from pathogens and patients, investigators at CDC can identify possible outbreaks by matching what amounts to the fingerprints of specific strains of bacteria and viruses.

When foods are suspected to be the source of an outbreak, samples are tested by the Food and Drug Administration and if pathogens are found, they can be checked against the patients’ pathogen patterns in the CDC’s PulseNet database.

The current cluster of E. coli illnesses involves “Shiga toxin-producing E. coli,” or STEC, for short, according to the CDC spokeswoman.

“People of any age can become infected. Very young children are more likely than others to develop severe illness and a complication called hemolytic uremic syndrome, but even healthy older children and adults can become seriously ill,” according to the CDC’s web page on E. coli.

The symptoms of STEC infections vary for each person but often include severe stomach cramps, diarrhea that is often bloody, and vomiting. If there is fever, it usually is not very high, generally staying below 101 degrees F. Most people get better within a week, however some E. coli infections are severe or even life-threatening.

Around 5  to 10 percent of those who are diagnosed with E. coli O157 infection develop a potentially life-threatening complication known as hemolytic uremic syndrome (HUS). Clues that a person is developing HUS include decreased frequency of urination, feeling very tired, and losing pink color in cheeks and inside the lower eyelids.

People with HUS should be hospitalized because their kidneys may stop working and they may develop other serious problems. Most people with HUS recover within a few weeks, but some suffer permanent damage, require kidney transplants or die.