Name a common opportunistic infection associated with AIDS.

Pneumocystis pneumonia (PCP) is a common opportunistic infection associated with AIDS because it predominantly affects individuals with weakened immune systems, particularly those with a CD4 count below 200 cells/mm³. This infection is caused by the fungus Pneumocystis jirovecii, which is typically harmless in healthy individuals but can lead to severe respiratory illness in those with compromised immunity, such as AIDS patients.

The link between PCP and AIDS is significant, as it often serves as a clinical indicator of the progression to AIDS and highlights the critical role of immunocompromise in increasing susceptibility to certain infections. Routine prophylaxis for PCP is recommended for patients with advanced HIV/AIDS to prevent the onset of this potentially life-threatening condition.

While tuberculosis is also an important opportunistic infection often seen in individuals with HIV, its association is more widespread and not exclusive to AIDS alone. Hepatitis C and influenza, though they can pose risks to patients with HIV, do not specifically act as opportunistic infections unique to AIDS. They are not directly linked to the major immunocompromised state characteristic of AIDS. Therefore, PCP stands out as a key opportunistic infection in this context.