Human Immunodeficiency Virus (commonly known as HIV) is a virus that damages the body’s immune system so it cannot fight off infections. It is preventable and treatable, but not curable. Anyone can get and transmit HIV.
HIV lives in the blood and some bodily fluids (semen, including pre-cum, and vaginal fluids). HIV can be transmitted through:
- Vaginal or anal sex without a condom
- Oral sex without a condom (although this is rare)
- Sharing sex toys without washing them or covering them with a condom with each use
- Use of unsterile injecting equipment
If you are living with HIV, it can also be transmitted during pregnancy, childbirth or breastfeeding.
Bodily fluids such as urine, sweat or saliva do not contain enough of the virus to infect another person. You cannot get HIV from casual contact such as kissing or hugging.
Acquired Immune Deficiency Syndrome (commonly known as AIDS) is an advanced stage of HIV infection, when your immune system is damaged and weakens your ability to fight common infections. However, with early diagnosis and effective treatment, most people with HIV will not develop AIDS.
Most people with HIV will experience signs seroconversion, a short, two-week illness soon after getting the virus. Seroconversion can feel like a flu (with sore throat, fever, tiredness, achy joints, swollen glands and a rash), and in some cases it could be severe enough to put you in hospital. However, a small number of people will not experience any noticeable signs or symptoms.
After seroconversion, a person with HIV may not have symptoms for many years and might look and feel well, but the virus will be multiplying in their body, causing progressive weakening of the immune system. Following this period, symptoms may include weight loss, persistent diarrhoea, night sweats, and infections that keep returning.
The earlier that someone with HIV gets a diagnosis, the more likely it can be treated so it is important to get tested if you think you may have been exposed to HIV. Delaying testing and treatment will allow the virus to weaken your immune system. It also means you could pass the virus to someone else.
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. However, most tests do not detect the virus itself but the antibodies that your body has developed to fight it and are most accurate after twelve weeks.
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.
In some places, you may be able to do the test by yourself in the privacy of your home or another convenient place. If the test is ‘reactive’, you will need to visit a healthcare provider for further testing to confirm whether you have HIV and require treatment.
It is recommended that all people with HIV start treatment as soon as possible after diagnosis. In some places, you may receive regular blood tests to check how your immune system is coping and will only recommend treatment if the cells in your blood that fight infection have dropped below a certain level.
The treatment helps to manage the 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, allowing 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. These drugs will suppress the amount of virus in the body, stop the progression of infection, and prevent transmission of HIV to others.
There are several ways to reduce the risk of infection and protect yourself and your sexual partners from HIV. When used correctly and consistently, condoms are one of the most effective methods of protection against HIV and other STIs.
There is also a medicine called PrEP (pre-exposure prophylaxis) for people who do not have HIV. PrEP is taken before sex and can reduce the risk of HIV transmission 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 STIs, and you should wear a condom every time you have sex (whether it is anal, oral or vaginal).
If you think you may have already 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 often recommended if you are at high-risk of exposure (for example, if a partner is known to be HIV positive).
It's also a good idea to get tested before each new sexual partner or every three to six months.
Learn more about different types of STIs and their symptoms, treatment, and prevention
HIV and STIs