Camp activities had occurred in a wooded park with 12 campsites, nine of which were open, dirt-floor shelters with roofs supported by posts. During May 21–May 25, counselors participated in a precamp clean-up week. Activities included raking leaves, cleaning picnic tables, digging fire pits, and moving firewood; counselors did not wear personal protective equipment while cleaning. They reported observing bat guano on picnic tables and dirt floors in two of the shelters. Day camps began on June 4, 2012, each lasting from Monday through Friday. Campers were aged 6–14 years (median: 9 years); each was assigned to one campsite, where activities included cooking on wood-fired grills and eating at picnic tables. Camp activities included nature walks, outdoor games, wilderness skill training, archery, and arts and crafts; all campers participated in these activities, but none participated in high-risk activities (e.g., digging in dirt, digging fire pits, raking leaves, or cleaning campsites).