The state water patrol has rescued a St.Louis couple from their houseboat on the Mississippi River near St. Charles. Both were suffering from carbon monoxide poisoning. The husband already was unconscious.

The patrol says the CO-2 alarm was not working on the couple’s houseboat this weekend and they almost died. Both were hospitalized.

Patrol spokesman Nick Humphrey says carbon monoixide poisoning on boats does not happen very ofen—but often enough to be a concern. He says it usually happens to people inside a houseboat-type of vessel. But sometimes people who are swimming or "laying around" the back of a boat that is idling also can be overcome by the carbon monoxide in the exhaust.

The worst Missouri carbon monoxide boating incident that Humphrey can recall happened at the Lake of the Ozarks, when six people died because exhaust from a boat generator got into the enclosed cabin