Legionella pneumophila is the etiologic agent of both Legionnaires disease and which condition?

Legionella pneumophila is the etiologic agent of both Legionnaires disease and which condition?

• A. Swine fever
• B. Pontiac fever
• C. Rift Valley fever
• D. San Joaquin Valley fever

Answer: (B)

Legionella pneumophila can cause two distinct clinical pictures in humans: Legionnaires disease and Pontiac fever. Pontiac fever is a mild, self-limited flu-like illness without pneumonia, occurring after inhaling aerosolized water containing the bacteria. Symptoms typically include fever, malaise, myalgias, and headache and resolve within a few days without treatment. The other listed diseases are caused by entirely different pathogens (swine fever by a virus in pigs; Rift Valley fever by a virus; San Joaquin Valley fever by a fungus), so Pontiac fever is the correct associated condition.

Legionella pneumophila can cause two distinct clinical pictures in humans: Legionnaires disease and Pontiac fever. Pontiac fever is a mild, self-limited flu-like illness without pneumonia, occurring after inhaling aerosolized water containing the bacteria. Symptoms typically include fever, malaise, myalgias, and headache and resolve within a few days without treatment. The other listed diseases are caused by entirely different pathogens (swine fever by a virus in pigs; Rift Valley fever by a virus; San Joaquin Valley fever by a fungus), so Pontiac fever is the correct associated condition.