Chain of infection

Question 1

What are the 6 step of the chain of infection?

Answer 1

1. Infectious Agent
2. Reservoir
3. Portal of Exit
4. Mode of Transmission
5. Portal of Entry
6. Susceptible Host

Question 2

Infectious Agent

Answer 2

Microorganisms (such as bacteria, viruses, fungi, or parasites) cause infectious diseases.

Question 3

Reservoirs

Answer 3

Host in which infectious agents live, grow, and multiply.

Reservoirs can be humans, animals , or the environment.

Question 4

Portal of Exit

Answer 4

The route through which an infectious agent escapes or leaves the reservoir.

Ex: pathogens causing respiratory disease escape through the nose or mouth.

Question 5

Mode of Transmission

Answer 5

How an infectious agent travels to other people or places.

Modes of transmission include contact (touching contaminated surfaces), droplet (coughing or sneezing), or airborne (depending on the size of the organism).

Question 6

Portal of Entry

Answer 6

The route through which an infectious agent enters a new host.

It is the reverse of the portal of exit (e.g., pathogens entering through the respiratory tract)

Question 7

Susceptible Host

Answer 7

The individual who can become infected.

If any link in the chain is broken or neutralized, transmission of infection wont occur.