MADISON, Wis. -- State officials said that they have so far not found a deadly fish disease in most of Wisconsin's thousands of waterways -- a month after it was found for the first time in the state.

The hemorrhagic septicemia virus, or VHS, was found last month in fish from the Lake Winnebago system in east central Wisconsin. State officials later found the virus in Lake Michigan.

Mike Staggs of the state Department of Natural Resources said that they haven't detected VHS anywhere else. In the last month, he said that they have responded to or investigated 78 fish deaths and tested fish from around the state. He said that the majority of fish deaths are from something other than VHS.

The state Natural Resources Board last month passed emergency rules on the Lake Winnebago System and Lake Michigan aimed at halting the spread of the virus.