To the Editor.
—I read with interest the recent article by Sienko et al,1 "Q fever: A call to heighten our index of suspicion." The authors describe two cases of Q fever that appeared in a rural area in Michigan and present data showing a surprisingly high prevalence of antibody to Coxiella burnetii in goats and among farming families that own goats.Even in an endemic area, physicians need to be reminded of the importance of Q fever. I found C burnetii to be the second most common cause of pneumonia in a healthy young adult population in Laredo, Tex.2 Most of my patients had no contact with farms or farm animals, and airborne dissemination of infective particles in an endemic area was thought to be responsible. Sienko et al1 did not indicate the time of year that their cases appeared; presumably they were in the late