AIDS is a blood-borne disease and can be contracted in three ways: blood-borne, sexual and mother-to-child. Blood transmission refers to the sharing of needles or syringes between a healthy person and a person with AIDS, resulting in the exchange of blood and causing infection. It can also be caused by sharing personal items such as razors, toothbrushes, nail clippers, etc., and the exchange of blood can lead to infection. Sexual transmission refers to unprotected sexual intercourse with a person with AIDS, resulting in the exchange of bodily fluids and infection in a healthy person. Mother-to-child transmission refers to the transmission of HIV from a mother with AIDS to her baby during pregnancy and breastfeeding after pregnancy, resulting in infection of the baby.