Healthy lives for young people


Find out about the symptoms, causes and treatment of HIV.

Human Immunodeficiency Virus (HIV) is a virus that damages the body’s immune system so it cannot fight off infections. HIV is most commonly transmitted (passed on) through vaginal or anal sex without using a condom. In 2017, around 100,000 people in the UK were living with HIV.

AIDS (Acquired Immune Deficiency Syndrome) is the final stage of HIV infection, when your body can no longer fight life-threatening infections. With early diagnosis and effective treatment, most people with HIV will not go on to develop AIDS.

Signs and symptoms of HIV

Approximately 80% of people with HIV will experience a short, two week illness soon after getting the virus. This illness is known as seroconversion and is a sign that the immune system is reacting to the virus. The body then produces antibodies; a protein in the blood that fights infection.

This illness can be like flu (with sore throat, fever, tiredness, achy joints, swollen glands and a rash) or it could be severe enough to put you in hospital.

If you experience all of these symptoms at the same time after being at risk of HIV, you should have an HIV test.

After this illness, you may not have symptoms for many years (and some people won’t even experience this seroconversion illness).

In the meantime HIV will multiply and cause progressive damage to your immune system, during which time you can look and feel well.

Once this damage is done, typical symptoms include:

  • Weight loss
  • Persistent diarrhoea
  • Night sweats
  • Infections that keep returning
  • Serious life-threatening illnesses


The earlier that someone with HIV gets a diagnosis, the more likely it is that these problems can be prevented.

The causes and spread of HIV

HIV lives in the blood and some bodily fluids, so to get HIV, one of these fluids from someone with HIV has to get into your blood.

The virus exists in blood, semen (including pre-come) and vaginal fluids. The commonest way for HIV to be transmitted from one person to another is through having unprotected vaginal or anal sex.

HIV can be transmitted through:

  • Vaginal sex
  • Anal sex
  • Sharing sex toys
  • Sharing needles
  • Oral sex: the risk of this is much lower, but there is a greater risk if someone with HIV ejaculates (comes) in your mouth, and you have ulcerated or bleeding gums.
  • Pregnancy, childbirth or breastfeeding: this is very rare in the UK. There are steps that can be taken to reduce the possibility of the child contracting HIV, including giving the mother and child antiretroviral HIV drugs, delivering the child by caesarean and not breastfeeding the baby.

Bodily fluids such as urine, sweat or saliva do not contain enough of the virus to infect another person. You cannot get HIV from shaking hands, kissing or hugging, using other people’s cutlery or cups, sharing towels, toilet seats, or going to swimming pools.

Who is most at risk?

  • Men who have sex with men are most at risk of getting HIV
  • Women who have sex with men who have sex with men are therefore also exposed to a higher risk
  • People who have had sex without a condom with a person who has lived or travelled in Africa
  • People who inject drugs
  • People who have had unprotected sex with people who inject drugs
  • People who have received a blood transfusion in Africa, eastern Europe, the countries of the former Soviet Union, Asia or central and southern America

The only way to prevent HIV is to use contraception such as condoms. Find out more about condoms.

Testing for HIV

HIV can’t be tested until at least four weeks after exposure to the virus, with more accurate results if the test is done six weeks after exposure to the virus. The test does not detect the virus itself but the antibodies that your body has developed to fight it.

Testing for HIV involves taking a small sample of blood for analysis. The test is either sent away to a laboratory and results come back in a few days, or same-day tests can give an instant result.

It is also possible to test a saliva sample or to test blood taken from pricking the finger with a needle.

Possible results

  • Negative: no sign of infection
  • Positive: infection is detected
  • False negatives: incorrectly identified as negative as antibodies haven’t reached a high enough level to be detected (around four weeks).
  • False positive: all positive results should be tested again to confirm as a ‘false positive’ may occur when antibodies fighting another infection are detected but wrongly identified as being antibodies fighting the HIV infection.


Delaying testing and treatment will allow the virus to damage your immune system. It also means you could pass the virus to someone else.

HIV testing is free on the NHS and can be provided at Brook services, GUM or sexual health clinics, clinics run by charities such as the Terrence Higgins Trust and some GP surgeries. Find your nearest using our find a service tool.

Free STI kits

At-home HIV self-sampling kits are also available free online for people in England at higher risk from HIV, such as men who have sex with men or people from black African communities.

  1. The kits are sent to your home free of charge.
  2. They are discreet and contain everything you need to take a finger prick blood sample.
  3. A prepaid envelope is provided to send your sample to a laboratory for testing
  4. You will receive your results in around five working days. You can choose how you would like to receive your results and can also track the status of your test.
  5. If the results show that it is likely you have HIV you will then be asked to visit a sexual health clinic to confirm the test.

It is also possible to buy other HIV self-testing kits online but it is important that you look for a CE quality assurance mark as poor quality tests are available and may not give you an accurate result.

Treatment of HIV

HIV is preventable and treatable, but it is not curable.

If you are HIV positive, you will receive regular blood tests to check how your immune system is coping. If these tests show that the cells in your blood that fight infection have dropped below a certain level, your doctor may recommend that you start treatment.

The aim of treatment is to manage this balance between the levels of HIV in your blood and the infection-fighting cells that your immune system has produced to fight it. It is treated with drugs called antiretrovirals, they work by stopping the HIV multiplying, which gives the immune system a chance to repair itself.

A combination of antiretrovirals is used because HIV can quickly adapt and become resistant to them. The combination that is most effective will be unique to each person.


If you think you may have been exposed to HIV within the last 72 hours (three days), it is also possible to take anti-HIV medication called PEP (post-exposure prophylaxis) which may stop you becoming infected.

PEP is a 28-day treatment of powerful drugs and is not guaranteed to work. It is only recommended after high-risk of exposure (for example, if a partner is known to be HIV positive). You can read more about PEP on the NHS website.


PrEP (HIV Pre-exposure Prophylaxis) is a medicine for people who do not have HIV (HIV negative). PrEP is taken before sex, and can reduce the risk of you getting HIV when it is taken correctly.

PrEP can be used as a way to reduce your risk of HIV if you are HIV negative and don’t always use condoms.

It is important to remember that PrEP will not protect you from other sexually transmitted infections (STIs) and you should wear a condom every time you have sex (whether it is anal, oral or vaginal).

Here are some things that could mean you are high risk:

  • If you have recently had an STI (especially syphilis, Hepatitis C or Lymphogranuloma venereum)
  • If you use PEP (post-exposure prophylaxis)
  • If you use recreational drugs (crystal meth amphetamine, mephedrone or GHB/GBL) – also known as Chemsex

PrEP is not a vaccine and only provides protection from HIV as long as you continue to take it as prescribed.

PrEP is now available on the NHS for people who are high risk, but it is not currently available in all sexual health clinics. An impact trial is taking place in a limited number of GUM clinics around England, but no Brook clinics are PrEP trial sites so it is not possible to get PrEP from Brook.

As there are risks associated with buying medication online and there are specific health risks associated with taking PrEP medication we do not recommend that you buy PrEP online.

However if you are considering purchasing your own PrEP medication online you should buy it from a reliable source and you should seek advice and support from an NHS sexual health clinic to assess whether the medication is right for you, and to ensure that essential tests are carried out before and during treatment.

HIV in schools campaign

This short film was made as part of the 2015 HIV in school campaign by Chiva, a registered charity working across the UK and Ireland to improve care for HIV positive children and their families.


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