* Bacteria: These are single-celled organisms that can cause a wide range of diseases, from simple infections like strep throat to serious conditions like tuberculosis.
* Fungi: These are multicellular organisms (though some are single-celled) that can cause infections like athlete's foot, ringworm, and yeast infections.
* Viruses: These are tiny infectious agents that can only replicate inside the cells of a living host. Viruses are responsible for many diseases, including the common cold, influenza, and HIV.
Important Note: While pathogens are often associated with causing disease, not all bacteria, fungi, or viruses are harmful. In fact, many are beneficial or even essential for life.
