Q: Transmission via droplets occurs within how many feet of an infected patient, and requires droplet isolation?
Answer: 3-6 feet
Many patients particularly chronically sick patients may be colonized with organisms that may disseminate via droplet. These include Neisseria meningitidis, Bordetella pertussis, influenza, parainfluenza, adenovirus, Haemophilus influenzae type b, Mycoplasma pneumoniae, rubella, Respiratory syncytial virus (RSV), and others. These particles are usually more than 5 microns, remain suspended in the air for a limited time, and risk of transmission is highest within 3-6 feet.
This need to understand that there is a difference between droplet isolation and airborne precautions. The doors of patient rooms may remain open in droplet isolations. Airborne Precautions are required for organisms/particles that remain suspended in the air,
travel on air currents and can be inhaled by others. These include Mycobacterium tuberculosis (TB), varicella (chickenpox) and measles viruses.
Ideally, an infectious disease service should be consulted to determine the proper level of isolation required.
1. United States Center for Disease Control and Prevention. 2007 Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings. https://www.cdc.gov/infectioncontrol/pdf/guidelines/isolation-guidelines-H.pdf (Accessed on November 01, 2019).