CLEVELAND - The Cuyahoga County Board of Health confirms that three children have been exposed to the E. coli bacteria. Two more cases are under investigation.

"Five cases is very unusual for us to have," says Terry Allan, the health commissioner in Cuyahoga County.

The three children with confirmed cases also have what's known as Hemolytic Uremic Syndrome (HUS). It is a particularly nasty side effect of exposure to E. coli that includes severe cramping, bloody stool, and kidney issues.

Health officials are not saying much about the children. Two are from Olmsted Falls and one is from Strongsville. They are either hospitalized or recovering at home.

Allan says the children must have contracted E. coli in one of two ways: either from a batch of meat that is contaminated or from just undercooked beef. Testing will be conducted on meat in the area, but so far, there is no indication that any particular batch of beef in Ohio is contaminated.

Any ground beef, though, can potentially carry E. coli. That's why officials say it is so important to cook beef thoroughly. "It's important that your burger is cooked to 160 degrees in the thickest part of the hamburger," Allan says. "If you don't have a thermometer, it's important that you cook that hamburger until it's no longer pink in the middle."

Allan says hand washing is also important, as is keeping your grill clean, and keeping your uncooked meat away from cooked products.

All the children with HUS have been exposed to a type of E. coli that is associated with ground beef.