A nurse becomes infected when she breathes in the bacteria that cause the disease tuberculosis. As
she starts to cough and releases some of that bacteria. Examine the diagram below that shows the
regarding this nurse.
Chain of Infection
Portal of entry
D
Host A
Transmission
c
Portal of exit
с
Infectious B
agent
Reservoir
What do the labels A, B, C, and D represent in the case of this nurse?
