Answers are grounded in this paper and cite their sources.
Lake water that was fecally contaminated by bathers was the most likely vehicle for the transmission of both the E. coli O157:H7 and the S. sonnei infections. The unusually prolonged outbreak suggests both the survival of these enteric organisms in lake water and a low infectious dose.
No takes yet. Share an insight, caveat, or question.
Keene et al. (1994) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: