Five young ladies, ages eight to eleven, enjoyed a two day summertime reunion in Michigan at the lakeside home of one of their families.

All five of the children had been adopted from China, and to attend the reunion some of the children had traveled from as far away as Oregon.

While their parents were otherwise occupied, the girls played outdoors on the wooded property and swam in the lake. The lake was an "inland lake" not one of the three Great Lakes that border much of the state of Michigan. There were mosquitoes and blackflies about.

By the evening of the first day one of the girls (a member of the host family) had developed an intensely pruritic papular rash on her exposed extremities. By the following day all five of the girls had similar rashes (see photo at left).

Other than the intense prurtitis the girls otherwise felt well and did not experience fever or other systemic symptoms. At least two of the children had been previously immunized for chicken pox. The vaccine status of the remaining three children was uncertain.

Direct or indirect exposure to which of the five items pictured at lower left most likely led to the development of the girls' rashes?