Question

The chain of infection explains how infection is transmitted from one person to another. Build on the following diagram using your understanding of the chain of infection (the 6 elements) and define each element below giving at least one example of each element.

Answer 1

Chain of infection consists of events that occur during the spread of infection starting from multiplication of organism in the reservoir.

It consists of six elements:

1. Organism : the chain of infection starts from organism. For eg. Falciparum plasmodium in malaria

2. Reservoir : reservoir of infection is the living or non living place where the organism grows and reproduce. For eg P falciparum grows in mosquito.

3. Portal of exit : portal of exit is the medium in which the organism grow and enters the host. For eg p. Falciparum grows in saliva of mosquito.

4. Means of transmission : means of transmission is the mode through which the organism enters the host through reservoir. For eg. P. Falciparum spreads enters host through mosquito bite.

5. Portal of entry : how the infection enters the host body. For eg. P. Falciparum enters host through the blood.

6. Vulnerable host : the infected host further spreads the infection. For eg. Infected humans