opportunistic pathogen

An opportunistic pathogen is a microorganism, like bacteria or fungi, that normally doesn't cause disease in healthy individuals but can lead to illness when the immune system is weakened or compromised. These pathogens take advantage of the body's decreased defenses—such as due to illness, medication, or immune disorders—to infect and cause disease. Examples include fungi like Candida or bacteria like Pneumocystis. Understanding these pathogens highlights the importance of maintaining a strong immune system and taking precautions in vulnerable situations to prevent infections.