| prevalence of coxiella burnetii infections among north dakota sheep producers. | a case of q fever in a sheep producer was detected by a surveillance system in north dakota in 1993, when q fever was not reportable. this is the first officially documented case in the state. to estimate the prevalence of coxiella burnetii infection and identify associated risk factors, we conducted a study covering the whole state. a total of 17 cases were identified among 496 sheep producers, their family members, and hired helpers. the number of sheep raised was a good predictor of c. burnet ... | 1998 | 9830608 |