HIV
Also known as: human immunodeficiency virus, HIV infection, HIV and AIDS
HIV is a virus that attacks the immune system and, with treatment, can be managed as a long-term condition.
When to seek care
Anyone who thinks they may have been exposed to HIV can go to a sexual health clinic or, outside clinic hours, an A&E department, where PEP is available. NHS 111 Wales says PEP can help if started within 72 hours of possible exposure, ideally within 24 hours. A routine HIV test is available free from NHS sexual health services or a GP, or with a home kit. Terrence Higgins Trust's helpline, THT Direct, can connect people with an HIV doctor. NHS 111 can advise on urgent concerns, and 999 should be called in an emergency.
Overview
HIV is a virus that attacks the immune system. The NHS says most people have a short flu-like illness 2 to 6 weeks after infection, and the virus may then cause no further symptoms for many years. HIV is not the same as AIDS, which is the most advanced stage of infection. There is currently no cure, but the NHS says that with treatment most people with HIV can live a long and healthy life. The NHS and Terrence Higgins Trust both say that a person on effective treatment with an undetectable viral load cannot pass HIV on.
Causes
- Infection with the human immunodeficiency virus, a virus that attacks the immune system.
- The virus passes on when certain body fluids, such as blood, semen, vaginal fluids and breast milk, reach another person's bloodstream or mucous membranes.
- It can also be passed on by sharing needles.
- It can pass from a mother to her baby during pregnancy, delivery or breastfeeding.
Risk factors
- Sex without a condom, since the NHS says condoms are the most effective protection against HIV during sexual contact.
- Sharing needles or other injecting equipment.
- For a baby, being born to a mother who has a detectable viral load, or being breastfed by her.
Symptoms
What a clinician may find
- Swollen glands and a skin rash during the early flu-like illness.
- A high temperature and sore throat during the early flu-like illness.
Complications
- Opportunistic infections, which are certain illnesses that can lead to an AIDS diagnosis.
- Illnesses such as tuberculosis or lymphoma, which can indicate AIDS.
- AIDS, the most advanced stage of HIV infection, now generally described as late-stage or advanced HIV.
- Passing HIV on to a baby during pregnancy, delivery or breastfeeding, a chance that effective treatment lowers.
Diagnosis
HIV is diagnosed with a test, which the NHS provides free of charge to anyone. Testing can be done at a sexual health clinic, a GP surgery, with a home testing kit or with a home sampling kit. Testing uses a saliva or finger-prick blood sample, and laboratory results usually take a few days. If a first test is positive, a second blood test confirms the result. A test may not pick up HIV acquired very recently, a gap called the window period, and its length differs between tests. After a recent possible exposure, a negative result may be followed by a repeat test a few weeks later.
Treatment
HIV is treated with antiretroviral medicines, which stop the virus from copying itself in the body. These are taken every day, and the aim is an undetectable viral load. Terrence Higgins Trust recommends starting treatment straight away after diagnosis, regardless of CD4 count. HIV treatment is free on the NHS for anyone living in England.
Prevention
The NHS says condoms are the most effective protection against HIV and other sexually transmitted infections. PrEP is medicine taken by people without HIV to lower their chance of acquiring it, and it is provided free by NHS specialist sexual health services. PEP is a short course of medicine taken after a possible exposure. The NHS says sharing injecting equipment with a person who has a detectable viral load can spread HIV. The NHS also says that effective treatment with an undetectable viral load means HIV cannot be passed on to someone else.
Key facts
| Fact | Detail |
|---|---|
| Also called | Human immunodeficiency virus, HIV infection |
| What it is | A virus that attacks the immune system |
| How it is passed on | Through certain body fluids reaching the bloodstream, not through the air or casual contact |
| Early signs | A short flu-like illness 2 to 6 weeks after infection for most people; then often no symptoms for many years |
| Usually diagnosed by | A test at a sexual health clinic, GP surgery or with a home kit; a positive result is confirmed by a second blood test |
| Treatment | Daily antiretroviral medicines |
| Cure | No cure at present; treatment keeps the virus under control |
What is HIV, and is it the same as AIDS?
HIV is a virus that attacks the immune system. HIV and AIDS are not the same thing: HIV is the virus, while AIDS is the most advanced stage of infection. Without treatment, the CDC says HIV generally moves through three stages, and the last stage is AIDS. The CDC adds that progression to AIDS is now less common, and that people who take HIV treatment as prescribed may never reach it.
NHS 111 Wales says that with early diagnosis and effective treatment, most people with HIV will not develop any AIDS-related illnesses. There is currently no cure for HIV. It can be treated with antiretroviral medicines, and WHO describes it as a manageable long-term condition when prevention, diagnosis, treatment and care are available.
What are the symptoms of HIV?
The NHS says most people infected with HIV have a short flu-like illness 2 to 6 weeks after infection. Common signs include a high temperature, sore throat, rash, tiredness, joint or muscle pain and swollen glands. The NHS also notes that these symptoms are commonly caused by conditions other than HIV, so they cannot show whether someone has HIV.
After this early phase, HIV may not cause any further symptoms for many years, the NHS says. An HIV test is the only way to know for sure whether someone has HIV. Terrence Higgins Trust says body fluids are highly infectious during the early weeks and months after transmission, which is one reason testing matters.
How is HIV passed on?
The NHS says that in the UK most cases of HIV are caused by sex with a person who has HIV without using a condom. Sharing needles, syringes or other equipment for injecting drugs with a person who has a detectable viral load is another route. WHO lists blood, breast milk, semen and vaginal fluids as the body fluids that carry HIV.
HIV can also pass from a mother to her baby. The NHS says this can happen during pregnancy or birth if the mother has a detectable viral load, and NHS 111 Wales lists breastfeeding as a route too.
HIV does not spread through the air like cold and flu viruses, NHS 111 Wales says. WHO states that people cannot become infected through ordinary day-to-day contact such as kissing, hugging, shaking hands or sharing personal objects, food or water. The CDC describes transmission through kissing alone as extremely rare.
How is HIV diagnosed?
The NHS says an HIV test is the only way to confirm infection, and NHS 111 Wales says HIV testing is provided free of charge to anyone. Testing is available at sexual health clinics and GP surgeries, and home testing and home sampling kits are also available. Testing uses a saliva or finger-prick blood sample, and laboratory results usually take a few days, according to the NHS.
If a first test is positive, a second blood test is done at a clinic to confirm the result.
A test may not detect HIV acquired very recently. This gap is called the window period, and the CDC says no HIV test can detect HIV immediately after infection. After a recent possible exposure, a negative result may be followed by a repeat test a few weeks later, according to the NHS.
What treatment is available, and what does undetectable mean?
The NHS says HIV is treated with antiretroviral medicines taken every day, which stop the virus from copying itself and let the immune system recover.
The aim is an undetectable viral load, meaning the amount of virus in the blood is too low for tests to detect. The NHS says this usually takes around six months after starting treatment, and Terrence Higgins Trust says it can take up to six months for some people. Terrence Higgins Trust recommends starting treatment straight away after diagnosis, regardless of CD4 count.
The NHS says that someone on effective treatment with an undetectable viral load cannot pass HIV on to someone else. NHS 111 Wales says this applies to sex once the viral load has been undetectable for six months or more. This is known as U=U, undetectable equals untransmittable.
How can HIV be prevented?
The NHS says condoms are the most effective protection against HIV and other sexually transmitted infections. PrEP, or pre-exposure prophylaxis, is medicine taken by people without HIV to lower their chance of acquiring it. It is provided free by NHS specialist sexual health services in England, Scotland and Wales. The NHS says it usually comes as tablets taken every day or on demand. PrEP does not protect against other sexually transmitted infections, an NHS sexual health service says.
PEP, or post-exposure prophylaxis, is a short course of medicine taken after a possible exposure to HIV. It is available from sexual health clinics and, outside clinic hours, A&E departments. NHS 111 Wales says it can help if started within 72 hours of possible exposure, ideally within 24 hours.
Living with HIV
The NHS says that with treatment most people with HIV can live a long and healthy life, and NHS 111 Wales describes a near-normal lifespan with early diagnosis and effective treatment.
HIV services in England are open access, so adults with a diagnosis can refer themselves to a provider of their choice, according to the NHS England service specification. The same specification says newly diagnosed people should be assessed on the same day if they have symptoms, and within two weeks if they do not.
Terrence Higgins Trust runs a helpline, THT Direct, which can also connect someone with an HIV doctor if they do not have one yet. It also runs peer support in which every member, including the volunteers who run it, is living with HIV.
Frequently asked questions
Is HIV the same as AIDS?
No. HIV is a virus, while AIDS is the most advanced stage of HIV infection. The CDC says progression to AIDS is now less common, and that people who take HIV treatment as prescribed may never reach it. NHS 111 Wales says that with early diagnosis and effective treatment most people with HIV will not develop any AIDS-related illnesses.
Can a person with HIV pass it on if they are on treatment?
The NHS says that someone on effective treatment with an undetectable viral load cannot pass HIV on to someone else. NHS 111 Wales says this applies to sex once the viral load has been undetectable for six months or more. This is known as U=U, undetectable equals untransmittable. Condoms still protect against other sexually transmitted infections.
Can HIV be passed on by kissing or sharing food?
WHO states that people cannot become infected through ordinary day-to-day contact such as kissing, hugging, shaking hands or sharing food or water. The NHS says closed-mouth kissing carries no risk, and NHS 111 Wales says the virus does not spread through the air like cold and flu viruses.
Is there a cure for HIV?
There is currently no cure for HIV. It can be treated with antiretroviral medicines, which stop the virus from replicating. With access to effective prevention, diagnosis, treatment and care, WHO describes HIV as a manageable long-term condition that lets people live long and healthy lives.
Where can someone get tested for HIV?
NHS 111 Wales says HIV testing is provided free of charge to anyone on the NHS. It is available at sexual health clinics and GP surgeries, and home testing and home sampling kits are also available. If a first test is positive, a second blood test confirms the result.
Connected pages in detail
What each linked page on Anatomy Nexus covers, in a line, for HIV.
Symptoms
- Fever A body temperature of 38 °C (100.4 °F) or more, produced when the hypothalamus raises its set point in response to inflammatory signals.
- Rash Any change in the colour or texture of the skin.
- Swelling (oedema) Excess fluid in the tissues.
- Fatigue Persistent tiredness that rest does not fix.
Medical tests
- HIV test A blood test that looks for the human immunodeficiency virus.