Words to Know...

Agent - a substance that brings about a chemical or physical effect or causes a chemical reaction
Communicable - capable of being transmitted from person to person, animal to animal, animal to human, or human to animal
Epidemiology - the study of how diseases spread and can be controlled
Microbe - microorganism or germ
Pathogen - a specific causative agent (as a bacterium or virus) of disease
Vector - an organism (as an insect) that transmits a pathogen from one organism or source to another