The microorganism uses that person’s body to sustain itself, reproduce, and colonize. These infectious microscopic organisms are known as pathogens, and they can multiply quickly. Examples of pathogens include:

• bacteria
• viruses
• fungi

They can spread in several different ways, including through:

• skin contact
• the transfer of bodily fluids
• contact with feces
• ingesting contaminated food or water
• inhaling airborne particles or droplets
• touching an object that a person carrying the pathogen has also touched

In this article, we explain the different types of infections, how to reduce the risk of infection, and what symptoms they cause.