● Through food and water- if one consumes food or water contaminated with bacteria, viruses, worms etc. He/she can come down with diseases such as hepatitis, cholera, etc.
● Through contact- some diseases are spread from one person to the other through contact. E.g. scabies, ring worms, etc.
● Through body fluids- some germs are present in body fluids like sweat, semen, blood. When another person comes in contact with contaminated body fluids the diseases gets transmitted to him/her. E.g. Ebola, HIV, etc.
● Through air- some germs are air-borne and can be transmitted through the air from one infected person to the other. E.g. tuberculosis, influenza, etc.
● Through sexual contact- they are called Sexually Transmitted Diseases. E.g. HIV, gonorrhea, herpes, etc.
● Vectors- These are organisms that carry the germs from one place to the other. E.g. mosquitoes, dogs, fly, etc.