Infectious agents are biological entities that cause diseases or infections in humans, animals, or plants. These include:
- Bacteria: Single-celled microorganisms that can cause diseases such as tuberculosis and cholera. - Viruses: Tiny infectious particles like HIV and influenza that require a host cell to replicate. - Fungi: Organisms such as molds and yeasts, responsible for diseases like athleteâs foot and histoplasmosis. - Parasites: Organisms that live on or inside a host, causing diseases like malaria and toxoplasmosis.
