Several residents of a long-term care facility develop febrile illness within a short period of time. Symptoms include fever, nonproductive cough, myalgia, rigors, dyspnea, and diarrhea. Organisms found in induced sputum samples stain poorly with Gram stain but are visualized easily using silver stain. Urine testing for bacterial antigens is positive in most of the affected individuals. Which of the following is the most likely source of this outbreak?

Question

Several residents of a long-term care facility develop febrile illness within a short period of time.  Symptoms include fever, nonproductive cough, myalgia, rigors, dyspnea, and diarrhea.  Organisms found in induced sputum samples stain poorly with Gram stain but are visualized easily using silver stain.  Urine testing for bacterial antigens is positive in most of the affected individuals.  Which of the following is the most likely source of this outbreak?

Quizplus · Accepted Answer

Eductional Objective: Legionella pneumophila commonly contaminates natural bodies of water, municipal water supplies, and water-based cooling systems.  The organism is inhaled in aerosolized water and establishes infection via the pulmonary route.  Diagnosis is generally made by urine antigen testing, silver stain, or culture on buffered charcoal yeast extract agar supplemented with L-cysteine and iron.

Several Residents of a Long-Term Care Facility Develop Febrile Illness