Giardiasis is an intestinal illness caused by a microscopic parasite called Giardia lamblia. It is a very commonly reported cause of diarrheal illness in Wisconsin, with an average of 1,200-1,300 cases reported in Wisconsin each year. Cases may occur sporadically or in outbreaks.

Information on this page has been organized into two categories. Please choose one of the following.

Additional Info Group

Last Revised: February 5, 2021