DENVER -- A summer camp evacuated after a norovirus outbreak made 87 people sick has begun the long cleaning process.

Communications Director Laurie VanHorn said staffers have already started cleaning the swing sets, balls, toys and facilities at Camp Chief Ouray.

VanHorn did not say when the cleaning would be complete but said organizers hope to have everything finished to reopen on June 29.

The outbreak began with two girls who came to camp who reported feeling a little sick.

Counselors thought the girls had car sickness but then their whole cabin became ill, with symptoms including vomiting, cramping, diarrhea and a low-grade fever.

The gastrointestinal virus is easily spread in places where people are living in close quarters, such as nursing homes and summer camps.

A similar outbreak happened at the camp in 2005.