Question

Define: primary & secondary infection. [3 marks] Provide a specific example to illustrate this. [2 marks]

Answer 1

Primary infection: the initial infection of a host by a pathogen that has completed a resting or dormant period. During a primary infection, your body has no innate defenses against the organism, such as antibodies.

Examples:

1) Virus:

These enter the body and

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spread to other cells, and

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can cause mild like the common cold, or life-threatening, such as HIV or hepatitis-C.

2) Bacteria:

They can lead to primary infections, bacteria tend to be secondary infections, which enter the body after it's been weakened by a virus. Strep throat and botulism are examples of bacterial infections.

Secondary Infection:

A secondary infection is an infection that occurs during or after treatment for another infection. It may be caused by the first treatment or by changes in the immune system.

2 examples of Secondary infection:

• A vaginal yeast infection after taking antibiotics to treat an infection caused by bacteria
• Pneumonia caused by bacteria or fungi after having an upper respiratory infection (like a cold) that was caused by a virus