Timeline: HIV and AIDS

1930s

Researchers believe that sometime in the 1930s a form of simian immunodeficiency virus (SIV) jumped to humans who butchered or ate chimpanzee bush meat in the Democratic Republic of Congo. The virus becomes HIV-1 the most widespread form found today

1959

The world's first known case of AIDS has been traced to a sample of blood plasma from a man who died in the Democratic Republic of Congo in 1959

1960s

HIV-2, which is restricted to West Africa, is thought to have transferred to people from sooty mangabey monkeys in Guinea-Bissau during the 1960s

A genetic analysis of HIV in 2003 suggests that it may have first arrived in the United States in about 1968

1970s

During the 1970s it continues to spread undetected in the US and around the world - the pandemic has begun

1981

A high prevalence of both a rare type of skin cancer - Kaposi's Sarcoma - and pneumonia are found in young gay men in New York and California, US. These are the first documented cases of AIDS. By the end of the year 121 people are known to have died from the mysterious affliction

1982

Centers for Disease Control and Prevention (CDC) scientists, in Atlanta, US, predict that the immune system disorder affecting gay men is due to an infection. They establish the term Acquired Immune Deficiency Syndrome (AIDS) and determine that aside from gay men, other groups at risk are injecting drug users, people of Haitian origin and haemophiliacs

By 1982 AIDS had been detected on five continents

It is revealed that a wasting disorder known in Africa as "slim disease" is a form of AIDS

1983

AIDS epidemics are developing in Europe: one in gay men who have visited the US, another in people with links to central Africa

Investigations begin into the occurrence of AIDS in Rwanda, Zaire and other African nations

1984

Using recently developed techniques, the retrovirus responsible for AIDS is independently discovered by Luc Montagnier of the Pasteur Institute in Paris, France, and Robert Gallo of the National Cancer Institute in Washington DC, US. It is later named the human immunodeficiency virus (HIV)

Cases of AIDS passed on through heterosexual intercourse begin to appear

1985

The first International AIDS conference is held in Atlanta, US

Following the previous year's discovery of the HIV virus, the first HIV test is licensed by the US Food and Drug Administration (FDA)

US blood banks are screened for the virus

1987

AZT (zidovudine), the first antiretroviral drug, becomes available to treat HIV sufferers after a successful clinical trial. The drug works by blocking the action of HIV's enzyme reverse transcriptase, stopping the virus from replicating in cells. AZT slows down the course of AIDS, delaying death

By 1987, 16,908 people have died from AIDS in the US. In total 71,751 cases of AIDS had been reported to the World Health Organization (WHO), 47,022 in the US

Estimating that as many as 5 to 10 million people could be infected with HIV worldwide, the WHO launches its Global Programme on AIDS

1988

WHO declares the first World AIDS Day on 1 December

1991

The red ribbon becomes an international symbol of AIDS awareness

1992

In the US, AIDS becomes the leading cause of death for 24 to 44 year old men

The first combination drug therapies for HIV are introduced, when the US FDA approves the use of the ddC, which also blocks reverse transcriptase, alongside AZT. HIV drug cocktails are more effective and the multi-pronged attacks slow down the development of drug resistance

1994

Using AZT to reduce the transmission of HIV from pregnant women to unborn fetuses is recommended in the US. A study shows it cuts the rate of maternal transmission to 8% - in women taking a placebo the rate was 25%

Over 12 years after the discovery of AIDS, the US government launches its first national media campaign explicitly promoting condoms

1995

Saquinavir, a new type of protease inhibitor drug, becomes available to treat HIV. These drugs result in defective HIV forming, which cannot infect new cells. This new more powerful drug heralds the start of Highly Active Antiretroviral Therapy (HAART) - a combination therapy regimen using a "cocktail" of drugs

One million cases of AIDS have been reported to the WHO, 19.5 million people have been infected with HIV since the epidemic began

1996

The International AIDS Vaccine Initiative (IAVI) - a non-profit organisation based in New York City - is set up to speed the search for an HIV vaccine

90% of all people infected with HIV now live in the developing world

1997

Annual US death rates from AIDS dramatically fall for the first time, due to the introduction of HAART

UN announces that 40 million children could have lost one or both parents to AIDS by 2010