(i) Infectious Diseases : The diseases which spread due to infection by micro-organisms are called infectious diseases. It is communicated from diseased person to healthy person, caused by some biological agents/pathogens like viruses, bacteria, fungi, protozoans, fungi worms.
(ii) Non-infectious Diseases : The disease which does not spread by contact between infected and healthy person through air and water, is called non-infectious disease. E.g., Arthritis, heart disease.
