At least 24 people, most of them children, have been infected with E. coli bacteria (search), and the outbreak might be connected to a petting zoo that was at the State Fair, authorities said.

Two of those stricken have developed a severe complication known as hemolytic-uremic syndrome (search), in which the number of blood platelets (search) suddenly drops, red blood cells are destroyed and the kidneys shut down. The syndrome can be life-threatening or cause permanent kidney damage.

The number of confirmed cases of E. coli infections rose to 24, and nine more cases are suspected, officials at the state Department of Health and Human Services said Wednesday.

Health officials are awaiting genetic tests on some of the bacteria to see whether the cases are related. So far, the most common link among victims is that some visited the petting zoo exhibit at the State Fair last month.

Of the 33 cases being examined, 15 have some link to the state fair, officials said. Eight people did not go to the fair, and investigators are awaiting information from the other 10.

"If it does turn out to be a petting zoo, there are thousands of people who were exposed, and they are widespread," said Dr. Jeffrey Engel, state epidemiologist. "People came to visit from other states."

The highly contagious E. coli bacterium commonly lives inside of animals and can be passed to humans by eating contaminated meat or through contact with manure, animals or contaminated surfaces.

Hand-washing is the most effective means of avoiding infection, and the exhibit at the fair had hand-washing stations.