What are opportunists?

Explanation

**Step-by-Step Solution:**

1. **Definition of Opportunists**: Opportunists refer to organisms, typically pathogens, that take advantage of certain opportunities to cause disease, particularly in individuals with weakened immune systems.

2. **Context of AIDS**: In the context of AIDS (Acquired Immunodeficiency Syndrome), the immune system is significantly compromised due to a low count of T-helper cells. These cells are crucial for signaling other immune cells to respond to infections.

3. **Impact on Immunity**: The reduction in T-helper cells leads to a decreased ability of the body to fight off infections. This means that even mild pathogens, which would normally be managed by a healthy immune system, can cause serious infections in an AIDS patient.

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