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Microbiology · Chapter 15

Respiratory Infections: Where They Strike

Five infections settle in different parts of the airway, and where they land shapes the signs, the cause, and the route out. Pick one to light up its home in the tract. Then run the air model below. Set the distance, the mask and the room airflow, and watch the dose you breathe in rise and fall.

The respiratory tract

Where the infection lands
Isolation precaution—
The airway runs upper tract at the top to lower tract at the bottom. Infections high up spread easily by talking and coughing. Infections deep in the lungs threaten the swap of oxygen.

The air between two peoplelive model

Droplets fall. Tiny nuclei float.
Dose breathed in
0
Exposure
—
Gear match
—

Pick an infection, then move the sliders.

Five airway infectionspick one to begin
One tract, many targetsThe airway is a single connected tube. It runs from the pharynx, the throat, down the trachea and the bronchi, to the tiny alveoli where gases are swapped. Pick a condition to see where it lands, what causes it, and how it is treated.

Set up the room

3 ft
Face covering
4 /h
A normal room swaps its air about 4 times an hour. An airborne isolation room with negative pressure does it 12 or more, and it keeps that air from drifting into the hall.