Question

Why are the persons taking drugs intravenously much more likely to acquire infections like AIDS and Hepatitis B?

Answer 1

Persons who are taking drugs intravenously do not care about syringes they used. Usually one syringe is used by multiple persons and viruses like HIV and Hepatitis B virus are more prone to enter the healthy cell via blood route. So contaminated syringe in this type of drug administration may transfer these viruses to more people as one other method can do. So infections like AIDS and Hepatitis B are more likely to be spread through these types of contaminated syringes used in drug administration intravenously.