Editing Infection Control and Safety (section)

=== Airborne Precautions ===

'''PPE:''' a fit-tested N95 filtering facepiece respirator or higher level respiratory protection (powered air-purifying respirator), donned before entering and removed '''after''' leaving the room. Perform a user seal check every time. Fit testing is required before first use and at least annually. '''Placement:''' an airborne infection isolation room (AIIR), meaning a negative-pressure room with at least 6 air changes per hour in existing facilities and at least 12 in new or renovated construction, air exhausted directly outdoors or through a HEPA filter, with the '''door kept closed''' and negative pressure monitored daily when in use. During transport, the '''patient''' wears a surgical mask, not an N95, and skin lesions are covered.

'''Common indications:''' pulmonary or laryngeal tuberculosis, measles (rubeola), varicella (chickenpox) and disseminated herpes zoster (both airborne '''plus''' contact), and smallpox. Localized herpes zoster in an immunocompetent patient requires only standard precautions with the lesions covered.

'''Application note.''' For measles and varicella, only immune staff should enter when possible. After an infectious patient leaves an AIIR, the room must remain vacant long enough for adequate air exchanges, roughly one hour at 6 air changes per hour and about 35 minutes at 12, before an unprotected person enters. Emphasize that the N95 protects the wearer, while the surgical mask on the patient protects everyone else by containing source droplets.

'''Tuberculosis specifics.''' Suspect active pulmonary tuberculosis with cough longer than three weeks, hemoptysis, night sweats, unintentional weight loss, and fever. Place in an AIIR immediately on suspicion, collect three sputum specimens for acid-fast bacilli, and teach adherence to multidrug therapy, since nonadherence drives resistance. A positive tuberculin skin test or interferon-gamma release assay indicates infection, not necessarily active disease; a chest radiograph and sputum are needed to distinguish latent from active disease.