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Often, the terms HIV and AIDS are used interchangeably, leading to confusion about their differences. Here, we’ll discuss the definition and differences of both terms.

HIV stands for ‘human immunodeficiency virus’. HIV belongs to a group of viruses called retroviruses. HIV attacks white blood cells within the immune system. These cells will stay infected for the rest of their lives. If untreated, HIV will develop into AIDS.

AIDS stands for ‘acquired immune deficiency syndrome’. (It’s sometimes referred to as ‘late stage HIV’ or ‘advanced HIV disease’.) It is an umbrella term for the illnesses that occur due to having untreated HIV infection for several years, by which point the immune system is severely damaged and unable to fight off infections. The illnesses and symptoms will vary for each person that has AIDS, but may include life-threatening infections and cancers.

Glossary

AIDS

Acquired Immune Deficiency Syndrome. A collection of specific illnesses and conditions which occur because the body's immune system has been damaged by HIV.

cure

To eliminate a disease or a condition in an individual, or to fully restore health. A cure for HIV infection is one of the ultimate long-term goals of research today. It refers to a strategy or strategies that would eliminate HIV from a person’s body, or permanently control the virus and render it unable to cause disease. A ‘sterilising’ cure would completely eliminate the virus. A ‘functional’ cure would suppress HIV viral load, keeping it below the level of detection without the use of ART. The virus would not be eliminated from the body but would be effectively controlled and prevented from causing any illness. 

HIV

Human immunodeficiency virus, the virus which causes AIDS. There are two variants: HIV-1, and HIV-2. HIV-1 is by far the most common worldwide. See ‘subtype’ for more information.

immune system

The body's mechanisms for fighting infections and eradicating dysfunctional cells.

vaccine

A substance that contains antigenic components from an infectious organism. By stimulating an immune response (but not disease), it protects against subsequent infection by that organism, or may direct an immune response against an established infection or cancer.

 

Every person who has AIDS has HIV, but not every person with HIV will develop AIDS. Because there are now lots of treatment options available for people living with HIV, far fewer people are developing AIDS. Often, those that do develop AIDS are people who have not been tested for HIV and have never taken treatment. Once started on HIV treatment, death due to AIDS can be prevented.

The only way to find out if you have HIV is to get tested for the virus. There is no test for AIDS as it is a collection of infections and illnesses that occur because of untreated HIV infection. Often, people can experience a range of them before HIV is discovered to be the cause. This is why AIDS is sometimes difficult to diagnose. 

Ultimately, HIV is a virus that attacks the immune system and AIDS is a term that can only be used when HIV has caused severe damage to the immune system.

Mercy Shibemba

Mercy Shibemba

Article author

Mercy is an award-winning activist and advocate for children and young people living with HIV. Sharing her story of growing up with HIV to educate, challenge and inspire. She works on youth engagement and participation across clinical trials, research and charities that support young people. She is also the Chair of The Social Innovation Partnership. 

Basic information

Myths and facts

Myths and facts

HIV and the immune system

HIV and the immune system

How treatment works

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