Since the virus was discovered in 1981, HIV has killed more than 32 million people.
HIV gradually weakens the body’s immune system, usually up to 10 years after infection.
A person living with HIV is considered to have developed AIDS when their immune system is so weak it can no longer fight off certain opportunistic infections and diseases, such as pneumonia, meningitis and some cancers.
One of the most common opportunistic infections among people living with HIV/AIDS is tuberculosis (TB).
According to the World Health Organisation, approximately 37.9 million people were living with HIV/AIDS, the majority of them in sub-Saharan Africa, at the end of 2018.
In 2019, Médecins Sans Frontières/Doctors Without Borders (MSF) cared directly for 59,400 people on first-line HIV antiretroviral treatment.
Help us prepare for the next emergency
HIV/AIDS: Key facts
PEOPLE LIVING WITH HIV WORLDWIDE
OF PEOPLE WITH HIV DON'T KNOW THEIR STATUS
PEOPLE ON FIRST-LINE HIV TREATMENT UNDER MSF CARE IN 2019
Sexual activities and the exchange of body fluids are the most common causes of the spread of HIV.
The virus can also be transmitted through childbirth, breastfeeding and sharing needles.
While some people may develop symptoms similar to flu within the first two to six weeks of catching the virus, others may not show signs for many years.
Once the initial flu-like symptoms disappear, HIV will not show any further symptoms for many years.
Meanwhile, the virus attacks and destroys the CD4 cells of the immune system, using the machinery of the cells to multiply and spread throughout the body.
Despite the availability of affordable rapid tests for HIV, knowledge of HIV status remains low in sub-Saharan Africa, where HIV prevalence is highest.
An estimated 60 percent of people living with HIV are unaware of their status and, in some settings, this figure is far lower.
A study in Kenya in 2009, for example, found that only 16 percent of HIV-infected adults knew that they were infected.
There is no cure for HIV/AIDS, although treatments are much more successful than they used to be.
A combination of drugs, known as antiretrovirals (ARVs), help combat the virus and enable people to live longer, healthier lives without their immune system rapidly declining.
MSF HIV/AIDS programmes offer HIV testing with pre- and post-test counselling, treatment and prevention of opportunistic infections, prevention of mother-to-child transmission and provision of ARVs for people in the late stages of the disease.
Our programmes also generally include support to prevention, education and awareness activities to help people understand how to prevent the spread of the virus.