The Virginia Department of Health is investigating two reports of apparent food-borne botulism in the Roanoke area.

The cases, which surfaced last week, occurred in one household and are related to home-canned food not in wide or commercial circulation, said Robert Parker, the department's regional spokesman. He declined to say if either case was fatal.

Botulism isn't contagious, according to the department's Web site.

The cases are isolated incidents and aren't believed to be an issue beyond that household, Parker said.

Both the cases reported last week were in the Alleghany-Roanoke City Health Districts , which cover eight localities in the western part of Virginia. Parker wouldn't specify where the reported cases originated, or when. The cases under investigation are awaiting laboratory results to confirm they are botulism, Parker said.

The illness is a rare and occasionally deadly form of food poisoning caused by a bacterial toxin and commonly associated with improper home canning of foods. The last reported case of food-borne botulism in Virginia was in 2002, according to state records through 2006.

Symptoms of food-borne botulism typically appear within hours to days of eating contaminated food and are fatal in about 5 percent to 10 percent of cases, according to the health department's Web site.

The illness produces symptoms that affect the nervous system's control over muscles and include blurred or double vision, dry mouth and paralysis that affect breathing.