Lab tests indicate there might be more than one source behind the 22 Escherichia coli infections reported across Northeast Tennessee and Southwest Virginia over the past two months. Virginia Department of Health Spokesman Robert Parker said the tests revealed two different DNA fingerprints in the bacteria that has caused the recent rash of illnesses. One type was found in three of the six E. coli infections reported in western Virginia. Another type was found in a majority of the 16 E. coli cases in Northeast Tennessee. Other test results are still pending.

“The three cases match each other, but they don’t match any of the cases from Tennessee,” Parker said of the Virginia cases, explaining that the test results “make it less likely” the 22 cases in the region all came from the same source. Still, Parker conceded, it is possible for more than one type of bacteria to come from the same source – a fact that complicates the public health investigation of the outbreak in both states.

“This is all just part of the puzzle,” Parker said as he delivered this week’s E. coli update. “It just means it’s the same type of bug and we still have no evidence that it came from a common source.”

Eighteen people in the region were diagnosed with E. coli infections between May 8 and June 11 – including a 2-year-old Dryden, Va., girl who died June 5. The number of cases reported in such a short period of time raised an alarm for public health officials in Virginia and Tennessee.

Kirshke’s office is still waiting on results from the U.S. Centers for Disease Control and Prevent regarding a series of E. coli cases that sickened five Northeast Tennessee residents May 14, May 16, May 23 and May 28. Preliminary tests completed by his office show the bacteria in these cases were from a non-O157 E. coli strain such as E. coli O103:H11, O69:H11 or O103:H2.

Kirshke’s office cannot determine exactly what type of strain is at work in those cases, which is why cultures of the bacteria involved in the infections were sent to the CDC. But the federal health agency is facing a backlog of E. coli testing, because outbreaks of the illness also have been reported in four other states – Alabama, Idaho, Texas and Oklahoma.

“They told me not to hold my breath,” Kirshke said, adding that he was told it could be several months before he gets his test results – a delay that will hinder his attempts to determine why so many people are getting sick in such a short amount of time.