Viral liver infections can be very severe; hepatitis B and D are transmitted through sexual contact, blood, and from mother to fetus. Vaccination and screening are the cornerstones of prevention.

HIV, or Human Immunodeficiency Virus, is a sexually transmitted human retrovirus. It weakens the immune system, and if left untreated, leads to AIDS.

The use of illicit drugs exposes individuals to various health, social, and legal risks. In light of this major public health issue, prevention is essential.