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What is HIV?

what is hiv

HIV is a virus that damages the immune system. It can’t be cured, but there is effective HIV treatment available.

Without treatment, your immune system will become weak and eventually you will start becoming ill. Particular AIDS defining illnesses can be a sign that you have developed AIDS, a syndrome caused by HIV infection.

Luckily because of the treatment available, most people with HIV in the UK are not diagnosed with AIDS and people who are can generally recover well.

What is HIV?

HIV stands for Human Immunodeficiency Virus. It was identified in the early 1980s and belongs to a group of viruses called retroviruses.

HIV stops the body’s immune system working properly. It does this by getting inside cells called CD4 or T-cells. HIV destroys or damages these cells, makes copies of itself and then infects and destroys or damages more cells.

As more cells are destroyed, your immune system gets weaker and can’t fight infections properly. This means you can get illnesses more easily.

HIV treatment can stop this process so that the immune system can still do its job properly.

Modern HIV treatment means that many people with HIV are living long, healthy lives.

What is AIDS?

AIDS stands for Acquired Immune Deficiency Syndrome.

If HIV isn't treated, the gradual weakening of the immune system will leave the body vulnerable to illnesses it would normally be able to fight off.

In the UK, if you develop certain AIDS-defining illnesses or opportunistic infections, you are diagnosed as having AIDS – sometimes called late-stage HIV.

You cannot 'catch AIDS' and there is no AIDS test.

AIDS is not considered a disease, but a syndrome – a collection of different signs and symptoms, all caused by the same virus, HIV.

If you've developed an AIDS-defining illness, this doesn't mean you cannot make a good recovery. Thanks to HIV treatment, many people who were diagnosed as having AIDS in the past are now living long and healthy lives.

More on HIV and AIDS:

Next: HIV transmission: how HIV is and isn't passed on ››



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The Information Standard: Certified member

This article was last reviewed on 13/6/2017 by Anna Peters

Date due for the next review: 13/6/2020

Content Author: S. Corkery (NAM)

Current Owner: Kerri Virani

More information:

Part 16: Questions for Those Who Still Have Questions, By Joel Gallant, M.D., M.P.H.; From Jones and Bartlett Publishers 2008 -- An excerpt from 100 Questions & Answers About HIV and AIDS, published by Jones and Bartlett Publishers, 2008. The Body

The HIV lifecycle, NAM Aidsmap

Factsheet: HIV lifecycle, Michael Carter, NAM Aidsmap, April 2014

HIV basics – HIV and AIDS, NAM Aidsmap

How HIV infects the body and the lifecycle of HIV, Avert, April 2017

Symptoms and stages of HIV infection, Avert, May 2017

HIV and AIDS, Patient info, by Dr Laurence Knott, April 2015

Health issues, NAM Aidsmap, July 2014

Table 1: Clinical indicator diseases for adult HIV infection, British HIV Association, UK National Guidelines for HIV Testing 2008

NHS Choices – HIV and AIDS

AVERT – What is HIV?

AVERT - What is AIDS?