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What is HIV?

what is hiv

HIV is a type of virus. It damages the immune system, which keeps your body healthy. HIV can’t be cured, but there is effective HIV treatment available.

Without treatment, your immune system will become weak. Eventually, you will start becoming ill. These illnesses are a sign that you have AIDS, a syndrome caused by HIV infection. You cannot catch AIDS and there is no AIDS test.

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) in our immune system. HIV destroys or damages these cells, makes copies of itself and then goes on to infect and destroy or damage 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.

Although HIV cannot yet be cured, it can be treated. 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 it causes leaves the body vulnerable to serious 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 also 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're on a one-way path to illness and death. Thanks to HIV treatment, many people who were diagnosed as having AIDS in the past are now living long and healthy lives.

Does HIV lead to AIDS?

You need to have been infected with HIV to develop AIDS.

A small number of people deny that HIV causes AIDS. There have been some claims that AIDS has been created artificially as part of a conspiracy or to make profits for drug companies, for example, but this is not the case.

Without HIV treatment and care, people with HIV will experience damage to their immune system and will develop AIDS-defining illnesses at some point in the future.

More on HIV and AIDS:

Next: All about the HIV test ››



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The Information Standard: Certified member

This article was last reviewed on 17/7/2014 by R. Bignami

Date due for the next review: 17/7/2017

Content Author: S. Corkery (NAM)

Current Owner: G. Hughson (NAM)

More information:

NHS Choices – HIV and AIDS

AVERT – What is HIV?

AVERT - What is AIDS?