HIV: Human Immunodeficiency Virus

Worldwide, nearly 40 million people are infected with HIV, the virus that causes AIDS. Here's the Quick Fire Science, with Phil Sansom...

HIV is the human immunodeficiency virus, and around one in 650 people have it in the UK.

Often the only symptom is a short flu-like illness a few weeks after infection, which lasts for a week or two.

However, long after this symptom disappears, HIV is infecting and damaging vital cells in your immune system. This can lead to AIDS, or acquired immunodeficiency syndrome.

If you have AIDS, your immune system has been severely damaged by HIV. You become vulnerable to a whole host of potentially life-threatening illnesses, from tuberculosis to cancer.

HIV is diagnosed with a blood or saliva test, at a clinic or using a kit at home. The earlier it’s diagnosed, the quicker you can start treatment, and the more chance you have of controlling the virus.

This treatment consists of daily tablets called antiretrovirals, which stop the virus from replicating itself. Often you need a combination of different antiretrovirals, as HIV can quickly develop resistance to a single one.

There is no cure for HIV or AIDS. However, with enough treatment, you may eventually have an undetectable viral load - meaning you have so little of the virus in you that you won’t transmit it.