An organism that infects its host with the disease is referred to as a pathogen, and the severity of the disease symptoms is referred to as virulence.
Pathogens include viruses, bacteria, unicellular and multicellular eukaryotes, as well as other taxonomically diverse organisms.
Typically, pathogens—microorganisms that can cause disease—enter our bodies through the mouth, eyes, nose, or urogenital openings, as well as through wounds or bites that compromise the skin's protective barrier.
There are numerous ways for organisms to communicate or spread.
Disease-causing bacteria are known as pathogens.
They enter our bodies through openings, use the resources of the host, reproduce, and cause serious infectious diseases.