Which measure should be taken to prevent exposure to Aspergillus?

• A. Use soft, carpeted rooms.
• B. Place severely immunocompromised patients in rooms with 12 air exchanges per hour.
• C. Use negative air pressure rooms for all patients.
• D. Open windows to let in fresh air.

Answer: (B)

Exposure prevention for highly immunocompromised patients focuses on environmental controls that lower airborne contaminants. Aspergillus spores are common in the air, so reducing the concentration of these spores around a high-risk patient is crucial. Having a room with 12 air exchanges per hour helps dilute and remove airborne particles quickly, lowering the patient’s exposure to spores. This approach is preferred over options that can increase exposure, such as carpeting that collects dust, opening windows that admit outdoor spores, or using negative pressure rooms for all patients (negative pressure is used to contain airborne pathogens when isolating an infected patient, not to protect every high-risk patient).