What are the major types of isolation precautions and when to apply them?

• A. Standard precautions always; contact precautions (gloves/gown) for direct/indirect contact; droplet precautions (mask within distance) for diseases spread by droplets; airborne precautions (N95 or higher and negative pressure room) for airborne transmissions.
• B. Standard precautions only when symptoms appear.
• C. Contact precautions require N95 respirator.
• D. Airborne precautions do not require negative pressure rooms.

Answer: (A)

Understanding how infections spread and how to protect yourself is the key here. Standard precautions are the baseline for every patient encounter and include hand hygiene and the appropriate use of gloves, gowns, masks, eye protection, and cough etiquette as needed to reduce exposure to blood, body fluids, nonintact skin, and mucous membranes. When a pathogen is transmitted mainly by direct or indirect contact, you apply contact precautions with gloves and a gown to prevent transfer via skin or contaminated surfaces. For infections spread through larger droplets that don’t travel far, you use droplet precautions, which involve staying at a safe distance and wearing a surgical mask when near the patient. For diseases that can be carried in the air as tiny particles over longer distances, airborne precautions are necessary and require a fit-tested N95 respirator (or higher) and a negative-pressure room to contain the pathogen. This approach—standard precautions for all, plus contact, droplet, or airborne based on transmission mode—best matches how isolation is actually implemented. The other options aren’t correct because they misstate when standard precautions are used, what PPE is needed for contact precautions, or whether negative-pressure rooms are required for airborne pathogens.