Disease-producing microorganisms. Pathogens consist of organisms that instill diseases into hosts and cause illnesses in human beings. Only a minimal amount of pathogens is necessary to create illnesses in the human body, such as only requiring 1% of bacteria. Microbes are highly infectious diseases that take the form of measles and flues and are responsible for various diseases from different kinds of microorganisms. These microbes are referred to as pathogens.