Term
Airborne transmission
Also: aerosol transmission, airborne spread, droplet nuclei, far-field transmission
Passing an infection through particles small enough to stay suspended in air and travel beyond the person who exhaled them. It makes the ventilation of a room part of how a disease spreads, rather than a matter of comfort.
What it is
Exhaled breath, speech and coughing release particles across a wide range of sizes. The large ones fall within a metre or two; the small ones evaporate to droplet nuclei that follow the air, remain suspended for minutes to hours, and can be inhaled by anyone sharing the room. The second route is what this term names, and it is the reason two people can infect each other without ever being close.
The practical consequences are all building consequences. The dose depends on how much shared air a person breathes, so it rises with occupancy, with time in the room and with the number of people, and falls with the rate at which air is replaced or cleaned. Carbon dioxide is used as its proxy, because it too comes out of people and accumulates in the same way.
The distinction from close-range spread is one of scale, not of biology: the same particles do both.
What the studies report
| Linked to | Effect | Population | Study design | Source | Checked |
|---|---|---|---|---|---|
| — | share-above 55.0 | — · university building | sampling of indoor air for respiratory virus RNA on a university campus and in a hospital, with patient samples taken alongside | F-1544 Surveillance of respiratory viruses by aerosol screening in … (2024) | machine |
| — | share-above 38.0 | — · hospital | sampling of indoor air for respiratory virus RNA on a university campus and in a hospital, with patient samples taken alongside | F-1545 Surveillance of respiratory viruses by aerosol screening in … (2024) | machine |
| — | share-above 96.7 | — | shotgun metagenomics of indoor air for respiratory virus surveillance: 90 indoor air samples tested with a respiratory qPCR panel and with metagenomic sequencing alongside clinical samples | F-1548 Shotgun metagenomics on indoor air for surveillance of respi… (2025) | machine |
Each row is one Finding — a sentence as printed in one study, recorded with its page in the Coridum Knowledge Base. Follow the Finding number for the exact wording and the citation. Checked says who verified the row: machine means every automatic check passed and the surrounding text was read; person means someone read the sentence in the document. Rows are re-checked by a person over time. The studies are curated in the Coridum Knowledge Base; the reading of them together is a Claim, shown separately.
Cite this page
Coridum Research. Airborne transmission. Coridum Knowledge G-0169, 16 September 2026. https://coridum.com/k/G-0169/