communicable disease is one that is spread from one person to another through a variety of ways that include: contact with blood and bodily fluids; breathing in an airborne virus; or by being bitten by an insect. How do these communicable diseases spread?
How these diseases spread depends on the specific disease or infectious agent. Some ways in which communicable diseases spread are by:
physical contact with an infected person, such as through touch (staphylococcus), sexual intercourse (gonorrhea, HIV), fecal/oral transmission (hepatitis A), or droplets (influenza, TB)
contact with a contaminated surface or object (Norwalk virus), food (salmonella, E. coli), blood (HIV, hepatitis B), or water (cholera);
bites from insects or animals capable of transmitting the disease (mosquito: malaria and yellow fever; flea: plague); and
travel through the air, such as tuberculosis or measles