🦠microbiology review
Pathogen
Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
A pathogen is a microorganism that causes disease in its host. Pathogens can be bacteria, viruses, fungi, or parasites.
5 Must Know Facts For Your Next Test
- Pathogens are capable of causing diseases by bypassing the immune system.
- Bacteria and viruses are the most common types of pathogens studied in microbiology.
- Some pathogens are opportunistic, meaning they cause disease primarily when the host's defenses are compromised.
- Pathogenicity refers to the ability of a pathogen to cause disease, while virulence is the degree of damage caused by the pathogen.
- Vaccines and antibiotics are critical tools for preventing and treating infections caused by pathogens.