Infectious diseases are illnesses caused by germs (such as bacteria, viruses and fungi) that spread from person to person, are transmitted by insects or other animals, or are present in the air, water, food, or soil. A communicable disease is spread from person to person, or from animal to person (i. e through body fluids or droplets). All communicable diseases are infectious. But not all infectious diseases are communicable (e.g.: tetanus is infectious but not communicable).
