How Pathogens Spread

Viruses can spread through direct contact from person to person, through bodily fluid or feces (poop), or can be transmitted on clothing or on surfaces.  Viruses can also be transmitted via a vector, such as a  mosquito.  

Bacteria can be transmitted in a similar way to viruses through direct contact of person to person or through indirect contact on a person’s clothing or by feces.  Bacteria can also be found in contaminated food sources, water sources, and in the soil.  Bacteria can be transmitted via a vector, the tick or a fly.

Vector is an organism, mosquito, tick, fly, that spreads a virus or bacteria from animal to person, or person to person.

Protozoa can be found in water supplies or transmitted by other animals, such as through bird feces.  Protozoa can also be transmitted via vectors, such as a mosquito. 

Fungal spores can be found throughout a person’s environment.  Fungus can also spread via direct contact between people.

Internal animal parasites are most commonly spread through contaminated feces.  Eating undercooked food or food that is contaminated may allow a person to pick up eggs or various types of worms.  Some worms can imbed through the skin of a person’s foot  and enter the human.