Health officials warned against eating cheese curds, which are blamed for transmitting the E. coli bacteria and making 28 people ill.

About a dozen victims had to be hospitalized because of the outbreak in western Wisconsin.In a news release Wednesday, health officials said it appeared the outbreak was confined to Chippewa and Eau Claire counties. They advised anyone in those counties who has bought cheese curds since the beginning of this month not to eat them.

Cheese curds are made from the curd, or the solid part of milk, that is separated from the liquid whey in the cheese-making process.

A specific brand name was not identified.