All statements regarding Legionella pneumophila are true except______________?
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Answer: D. Person to person transmission
Explanation
Legionella pneumophila is typically acquired through environmental water sources rather than person-to-person contact. Infectious aerosols from contaminated cooling towers or showers transmit the bacteria to human hosts. Option D is the correct exception because direct transmission between humans does not occur. Legionella bacteria thrive naturally in aquatic ecosystems and man-made water distribution systems. These intracellular pathogens can replicate inside free-living freshwater amoebae found in plumbing systems. Inhalation of microscopic water droplets containing the bacteria leads to severe pulmonary infections.
Hospital water systems require careful monitoring to prevent outbreaks of Legionnaires disease in vulnerable patients. Pneumonia caused by Legionella species is diagnosed rapidly using specialized urinary antigen detection tests. Environmental engineering controls help mitigate the growth of these bacteria in large building ventilation systems. Aquatic bodies serve as the primary natural environmental habitat for Legionella pneumophila. The ability to replicate inside freshwater amoebae helps these bacteria survive harsh environmental conditions. Urine antigen tests provide a reliable, rapid method for diagnosing Legionella pneumophila infections.
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