Most Infectious Diseases Are Caused By Bacteria Or Viruses. Infectious illnesses are those that develop from harmful microorganisms, like viruses, bacteria, fungus, or parasites.these illnesses can be transmitted directly or indirectly, from another person. Infectious are those diseases which are liable to be transmitted to people, organisms, etc.
Pathogens can be spread in different ways.noninfectious diseases are not transmitted from one. Organisms like viruses fungi bacteria parasites etc can cause a number of infectious diseases. This virus can be spread to another person in 48 hours.