Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
A droplet nucleus is a tiny particle that remains suspended in the air after the water in an exhaled respiratory droplet evaporates. These particles can carry infectious agents over long distances and time periods.
5 Must Know Facts For Your Next Test
Droplet nuclei are typically less than 5 micrometers in diameter.
They can remain airborne for extended periods due to their small size.
Droplet nuclei are a key factor in the airborne transmission of diseases such as tuberculosis and measles.
Unlike larger respiratory droplets, droplet nuclei do not settle quickly and can be inhaled by individuals across a room or even further away.
Control measures for diseases spread by droplet nuclei include proper ventilation, use of N95 respirators, and isolation rooms with negative pressure.
Review Questions
Related terms
Airborne Transmission: The spread of pathogens through aerosols or dust particles that remain infectious over time and distance.
Respiratory Droplets: Larger particles (>5 micrometers) expelled from the respiratory tract that typically settle quickly to surfaces.
Negative Pressure Room: A specially designed hospital room where air flows into but not out of the room to prevent pathogen escape.