Human immunodeficiency virus or HIV has the following modes of transmission:
(a) Sharing infected needles and syringes.
(b) From an infected mother to a child through the placenta.
(c) Unprotected sexual contact with an infected person.
(d) Transfusion of blood from an infected to a healthy person.

Alcohol and drugs have various adverse effects:
Alcohol and drug abuse lead to reckless and rash behaviour, depression, fatigue, aggression and violence.  It has several ill effects on the body, like damage to the liver and the nervous system, loss of weight and appetite, respiratory problems, heart failure, resulting coma and death. Use of needles may lead to transmission of AIDS. Consumption of excess alcohol by any family member can have devastating effects on the family. It leads to several domestic problems such as quarrels, frustrations, insecurity, etc. The person shows rash behaviour, violence, loss of interest in social and other activities. The person becomes a menace for family and society.