Human Immunodeficiency Virus (HIV) is a retrovirus that infects cells of the human immune system (CD4+ cells). HIV infection steadily weakens the body's defence system until it can no longer fight off infections such as pneumonia, certain cancers and other related illnesses. All of which can be part of Acquired Immunodeficiency Syndrome (AIDS). The term HIV/AIDS is widely used to refer jointly to the related illnesses.
HIV is commonly spread through sexual intercourse without a condom and through sharing needles, syringes and other injecting equipment. Also a mother who has HIV can infect her child during pregnancy, birth or via breastfeeding. Initially, there may be no obvious symptoms after infection with HIV, but the virus continues to multiply, infect and kill CD4+ cells. Without treatment, people who have HIV eventually become ill and can develop AIDS within 5 to 10 years.
Currently, there is no vaccine or cure for HIV/AIDS. However, there are drug treatments that work against HIV. Combinations of several antiviral medications are used to increase the effectiveness and help prevent HIV becoming resistant to the treatment. For the majority of people, these drugs can postpone, and possibly prevent, HIV-related illnesses and delay the progression to AIDS. The infectious complications of AIDS are treated with variety of antibacterial, antiviral and antifungal agents.