1457Febrile Illness at a State Correctional Facility — Illinois, 2013

Background. On August 29, health authorities were notified that 42 state prison inmates had become ill during the preceding 48 hours, with fever, headache, cough, and dyspnea. A respiratory virus was suspected, and the prison was placed on lockdown. During the following week, 50 additional inmates became ill. We aimed to identify a source and prevent further infections. Methods. We recommended laboratory testing for viruses, bacteria, and fungi; abstracted medical charts; interviewed inmates and staff; and conducted an environmental assessment. Cases were defined as illness in an inmate, including >2 of the following: temperature >100°F, chills, headache, chest pain, shortness of breath, cough, myalgia, or fatigue with onset after August 12. Results. Eighty-five inmates met the case definition, three of whom required hospitalization. Testing for 21 viral and bacterial respiratory pathogens was negative. Of the 82 symptomatic inmates who submitted blood or urine, 78 (95%) tested positive for acute histoplasmosis (64 had positive antigen; 69 had positive antibody). Seventyone of the 78 (91%) were housed in Cellblock X. Two weeks prior to the outbreak, two trees and their root systems directly outside Cellblock X had been removed for security reasons. These trees were roosting sites for some of the thousands of European starlings found nightly within prison grounds. Conclusion. Acute histoplasmosis can mimic a respiratory virus outbreak and should be considered in endemic areas. Disturbance of soil contaminated with the fungus Histoplasma capsulatum, which thrives in soil contaminated with bird droppings, likely aerosolized fungal spores and caused this large outbreak. To decrease the risk for future histoplasmosis cases, the prison should limit starling roosting sites by removing other facility trees without disturbing their roots. Disclosures. All authors: No reported disclosures.