All pathogens are defined as what?

Pathogens are specifically defined as microbes that can cause disease. This is a broad category that includes various types of microorganisms such as bacteria, viruses, fungi, and parasites. The key characteristic of a pathogen is its ability to invade a host and disrupt normal bodily functions, leading to illness.

The correct answer encompasses all harmful microorganisms, distinguishing them from beneficial organisms that play important roles in processes like digestion or immune function. Understanding pathogens is crucial in clinical settings because it informs infection control practices, diagnosis, and treatment strategies. By recognizing the variety of pathogens, healthcare workers can better prevent and manage diseases caused by these microorganisms.