HIV (human immunodeficiency virus) is a virus that damages the cells in your immune system and weakens your ability to fight everyday infections and disease.

Most people diagnosed with HIV in the UK acquire the virus through unprotected vaginal or anal sex. Public Health England recommends individuals at risk should test for HIV regularly, including gay, bisexual and other men who have sex with men and black African men and women.

It may also be possible to catch HIV through unprotected oral sex, but the risk is much lower.


Most people infected with HIV experience a short, flu-like illness that occurs 2-6 weeks after infection. After this, HIV may not cause any symptoms for several years.

It's estimated up to 80% of people who are infected with HIV experience this flu-like illness.

The most common symptoms are:

  • raised temperature (fever)
  • sore throat
  • body rash

Other symptoms can include:

  • tiredness
  • joint pain
  • muscle pain
  • swollen glands

The symptoms usually last 1-2 weeks, but can be longer. They're a sign that your immune system is putting up a fight against the virus.


There is currently no cure for HIV, but with early diagnosis and the availability of very effective drug treatments, most people with the virus can go on to live a long and healthy life.


PEPSE stands for Post-Exposure Prophylaxis following Sexual Exposure. It is a short course of treatment given to anyone who may have been exposed to HIV because they either haven’t used a condom or the condom has split. The treatment reduces the risk of becoming HIV positive if started within 72 hours of sexual exposure.

If you have had unprotected sex or your condom has split and your partner is HIV positive / high risk of being HIV positive or if you have been sexually assaulted, you should seek advice about PEPSE as soon as possible and within 72 hours.


AIDS is the final stage of HIV infection. This is when the immune system is so weak that it is unable to fight most infections.

Many people in the UK are carrying the infection without knowing it. It is important to test regularly for HIV infection (at least once a year, or whenever you have a new sexual partner).

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