How the HIV virus works

HIV is a retrovirus, so its genetic material is RNA, not DNA. Once inside a host cell, the viral RNA is converted into DNA and added into the host cell's DNA.
The virus infects and destroys cells of the body's immune system, specifically T-helper lymphocytes, causing their numbers to gradually decrease.
When the numbers of these cells are low, the body is unable to defend itself against infection, allowing a range of pathogens to cause a variety of opportunistic infections.
The onset of opportunistic infections is known as AIDS.

Transmission

HIV is spread by sexual contact through the exchange of body fluids.
The most common ways HIV is spread are through sexual intercourse, blood donation, and sharing of needles by intravenous drug users.
It can also be transmitted from mother to child across the placenta, through the mixing of blood during birth, and in breast milk.

There is currently no cure for AIDS and no vaccine for HIV. However, treatments are available to help people live with HIV, and drug therapy can slow down the onset of AIDS.
Antiretroviral drugs prevent the replication of the virus inside host cells, prolonging life but not providing a cure.
Combination therapy, which involves taking several drugs, can be complex.
Treating pregnant women with antiretroviral drugs has been successful in preventing HIV transmission to their fetuses.

Public health measures: Educating people about HIV transmission and encouraging behavioral changes to promote safer practices.
Barrier methods: Condoms, femidoms, and dental dams create a barrier against body fluids, decreasing the risk of virus transmission during intercourse.
Contact tracing: Identifying and offering HIV tests to individuals who may have been exposed through sexual intercourse or needle sharing with an HIV+ person.
Harm reduction: Injecting drug users are advised to stop sharing needles, and needle-exchange programs provide sterile needles in exchange for used ones.
Blood screening: Blood collected from blood donors is screened for HIV and heat-treated to kill any viruses.
Avoid breastfeeding: HIV+ women in high-income countries are advised not to breastfeed their babies.