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What is HIV?
- HIV (human immunodeficiency virus) is a virus that can be passed on through sex and in a few other ways
- If HIV is not treated, it can gradually damage someone’s immune system so they can’t easily fight off infections and may eventually develop serious illnesses or cancers
- HIV treatment is extremely effective. It stops HIV damaging the immune system so someone living with HIV can stay healthy
- HIV treatment reduces the amount of virus in the body to such a low level that there’s zero risk of passing on HIV during sex. This is known as “Undetectable equals Untransmittable” or “U=U”
How is HIV passed on?
HIV can only be passed on (transmitted) though certain body fluids, including blood, semen (cum, including pre-cum), vaginal fluids, anal fluids, and breast milk.
It cannot be passed on through saliva.
HIV is more likely to be passed on if someone doesn’t know they have the virus. It can also be passed on by anyone living with HIV who is not on effective treatment, even if they have no symptoms.
In the first few months after acquiring HIV, the amount of virus in the blood can be very high. So, HIV may be passed on more easily at this time.
Passing on HIV though condomless sex
HIV is most likely to be passed on from anal or vaginal sex without using a condom.
It’s possible, but much less common, for HIV to be passed on from sharing sex toys that have not been covered with a new condom or thoroughly washed.
Correct and consistent condom use significantly reduces the chance of passing on or acquiring HIV.
However, people on effective HIV treatment cannot pass on HIV to sexual partners even during condomless sex.
People living with HIV can only pass HIV on during condomless sex if:
- They don’t know they’re living with HIV
- They’re not accessing HIV treatment and care
- They take HIV treatment but have a detectable viral load (over 200 copies of the virus in each millilitre of blood). This can occur if treatment is not taken properly or it’s been started recently and has not taken full effect yet or is not effective in controlling the virus due to resistance
Individuals that have recently tested HIV negative can also take PrEP medication to protect themselves from acquiring HIV during condomless sex (see below).
Other non-sexual ways HIV can be passed on
- By sharing any kind of drug injecting equipment such as needles, syringes or spoons
- To a baby during pregnancy, birth or breastfeeding, although HIV treatment helps to prevent this
- When receiving blood (transfusion), blood products or other healthcare. This has not happened in the UK for many years due to strict infection control procedures
Ways to protect yourself from acquiring HIV
- Using condoms consistently and correctly
- Taking PrEP
- PEP: If you think you’ve been exposed to HIV in the last few days, check if an emergency treatment called PEP is suitable
- Regular STI/HIV testing
What are the symptoms of HIV?
Many people get an illness, a bit like flu, within a few weeks of acquiring HIV.
This is called seroconversion illness and can last for around 2 weeks.
Signs and symptoms may include:
- High temperature
- Sore throat
- A general body rash
- Tiredness
- Aches and pains
- Swollen glands in the armpits, neck or groin
Not everyone who acquires HIV will get these symptoms.
After the first few weeks, people can live with untreated HIV for months or years without any signs or symptoms.
Without treatment, someone living with untreated HIV will eventually start to get symptoms caused by damage to their immune system. These may include:
- Weight loss
- Long-lasting diarrhoea
- Night sweats
- Skin problems, like warts, cold sores, or genital herpes
- Thrush in the mouth
- Shingles
- Repeated gut infections
Symptoms in these early years can be varied and overlap with other conditions. This can be why the diagnosis of HIV can be missed or delayed as the symptoms are put down to other reasons.
In later years, if HIV is not treated, damage caused by the virus can lead to serious and life-threatening conditions like pneumonia, tuberculosis (TB), and some types of cancer. These are called AIDS-defining illnesses.
AIDS stands for Acquired Immune Deficiency Syndrome. It’s another name for late-stage HIV. With treatment, most people will get better from an AIDS-defining illness.
A blood test is the only way to be sure of your HIV status.
HIV testing in London
SHL makes it easy for Londoners to get a free HIV test when you need one.
Order your free postal testing kit online, take a small blood sample from your finger, post it to our lab, and get your results in a few days.
This test is highly accurate if done 45 days or more after the last time you may have been exposed to HIV.
If you think you may have been exposed to HIV more recently, you don’t need to wait. You can test now and do another test later. Our test can detect many cases of HIV after just 3 or 4 weeks.
If your test shows you may have HIV, we’ll give you support and help you get another test at a sexual health clinic to confirm the result. See “What happens once I get my HIV test results?” in the FAQs.
Free HIV and STI Testing Kit
Test for HIV and common STIs. Get your free NHS-funded STI test kit delivered to your door in London.
Take a self-sample at home and return it for free. Get your results online within a week.
Support if your clinic confirms you have HIV
Finding out that you’re living with HIV can feel like a lot. You might be shocked, scared, angry, numb—or none of the above. However you’re feeling, you’re not alone. And you’re not without options. With the right treatment and support, people living with HIV can live long, healthy lives – and can’t pass it on through sex. Find out more at https://doitlondon.org/living-with-hiv/newly-diagnosed/
How is HIV treated?
HIV treatment is usually given by a specialist outpatient HIV clinic or sexual health clinic. The clinics are often within, or close to, NHS hospitals. You’ll be referred to one of these clinics for treatment and support.
HIV treatment is also called antiretroviral therapy or ART. Treatment can’t cure HIV, but it’s extremely effective at stopping the virus damaging your immune system. It can also stop you from passing on HIV to your sexual partners.
Treatment is either a tablet or tablets which are taken every day, or injections given every 8 weeks. Treatment has very few side effects.
Your HIV clinic will discuss which treatment suits you. At the moment, you will need to take the treatment for the rest of your life. HIV treatment is continuously developed and improved. Future HIV treatments will be different and may need to be taken much less often.
Your clinic will do some blood tests to check how HIV has affected your body:
- The CD4 blood test measures your CD4 cell (or T cell) count. CD4 cells are part of the immune system. They’re the main type of cell that HIV destroys. The fewer CD4 cells you have, the less able your immune system is to fight infection. Once you start treatment, your CD4 cell count usually increases and this significantly reduces the risk of developing AIDS.
- The HIV viral load test looks at the level of virus in your blood, also known as your viral load. In someone recently diagnosed, there may be millions of particles (copies) of the virus in each millilitre of blood. HIV treatment aims to reduce your viral load to fewer than 50 copies of the virus in each millilitre of blood. This is called an undetectable viral load. Once your viral load is consistently lower than 200 copies of the virus in each millilitre of blood, you won’t be able to pass on HIV to your sexual partners. It can take up to 6 months after starting treatment to achieve an undetectable viral load. When your viral load has been undetectable for 3 to 6 months, there’s zero risk of passing on HIV to sexual partners. It’s important to keep taking your treatment to keep your viral load undetectable.
Do I need to tell my sexual partners?
If your blood tests confirm you have HIV, you’ll need to tell any sexual partners since your last HIV negative test.
If you’ve not had an HIV test before, an SHL adviser or a health professional at your clinic can discuss which of your previous sexual partners to tell.
If you had sex without a condom in the last 3 days with a partner who was not taking PrEP, they may be advised to get an emergency treatment called PEP (post exposure prophylaxis) to lower their chance of acquiring HIV.
You don’t have to share your HIV status if you don’t feel ready. If you feel like you can’t tell sexual partners, the SHL team or a health professional at your clinic can tell them without mentioning your name.
Informing and testing partners is really important because it lowers the chances of:
- Untreated HIV causing serious health problems in a partner who’s unaware they have it
- HIV being passed on to a partner’s other sexual partners
Taking care of your sexual health
Look after your health by using condoms, having regular STI check-ups, and encouraging sexual partners to test for HIV and other STIs.
Anyone who lives in an area covered by SHL can have up to 4 free STI testing kits a year.
If your HIV test comes back negative but you think you may be at risk of acquiring HIV in the future, consider whether an HIV prevention medicine called PrEP would be a good choice for you.
If you’re diagnosed with HIV, you may also have other STIs or viruses. It’s advisable to have a full sexual health screen, including tests for chlamydia, gonorrhoea, syphilis, hepatitis B and hepatitis C.
Your HIV clinic will discuss how to prevent passing on HIV, including achieving an undetectable viral load.
Whether or not you have HIV, if you have a higher chance of getting syphilis or chlamydia you may be offered doxyPEP. This is an antibiotic you take soon after sex to lower your chance of getting chlamydia or syphilis. Ask your local clinic if doxyPEP is suitable for you.
Related Pages:
More information about HIV and STI testing
