What action should the infection preventionist take first when a patient’s sputum smear shows 4+ acid-fast bacilli?

• A. Place the patient in a private room on airborne isolation
• B. Begin droplet precautions only
• C. Transfer the patient to a general ward with standard precautions
• D. Delay isolation until independent confirmation

Answer: (A)

Posing a high-grade acid-fast bacilli smear indicates active, highly contagious tuberculosis, which is spread through airborne particles. The immediate, best action is to place the patient in a private room with airborne isolation (preferably a negative-pressure room) to prevent transmission while testing and treatment proceed. Airborne precautions are required because TB can stay suspended in the air and infect others even with brief exposure, and a 4+ smear reflects a high bacillary burden. Droplet precautions or standard precautions won’t contain airborne spread, and waiting for independent confirmation could allow continued exposure. Along with room placement, ensure staff wear appropriate respiratory protection (N95) and pursue diagnostic confirmation and treatment.