Tularemia Outbreak Associated with Outdoor Exposure Along the Western Side of Utah Lake, Utah, 2007

Results. During the outbreak period, 14 cases of tularemiawere reported from five of Utah’s 12 health districts. The weekly attack rateranged from 0 to 2.1/100 lodge visitors from June 3 to July 28. Illness onset dates ranged from June 15 to July 8. The median delay between onset of symptoms and laboratory test for tularemiawas 14 days (range: 7–34 days). Cohort study respondents who reported deer-flybites while at the lodge (adjusted risk ratio [ARR] 5 7.2, 95% confidence interval [CI] 2.4, 22.0) and who reported having worn a hat (ARR55.6, 95% CI 1.3, 24.6) were more likely to become ill.