According to ............. , diseases are caused by microorganisms

Can have one cell or more, usually occur in places that are warm and damp. Example athlete’s foot.

A ............, carries a pathogen and transmits it to healthy cells.

Four conditions must be met before one can say that a certain pathogen causes a disease. These conditions are called .........................

HIV is transmitted through an exchange of bodily fluids, such as during sexual intercourse or sharing of infected needles, this is a type of .......................... contact

An organism that causes a disease is called

He hypothesizes the germ theory, that diseases are caused by small animals

Smaller than a bacteria, enter healthy cells, forcing them to replicate

Decided to try making healthy animals sick by injecting them with pathogens from a sick animal

He finds that cleaning his surgical tools reduces patients' infections