What are HIV and AIDS?
The human immunodeficiency virus (HIV) is a virus that affects the immune system. It gradually destroys cells called CD4 cells, which usually help the body stay healthy by fighting off disease.
If HIV is not treated, most people will develop severe immune deficiency within 10 years. At this point, the body is no longer able to fight infection and stop cancer from developing. This late stage of HIV infection is called acquired immunodeficiency syndrome (AIDS).
What are the symptoms of HIV infection?
Most people have no symptoms or just a mild flu-like illness when they are first infected, and it may be difficult to tell the HIV apart from other viral infections. This illness, called ‘seroconversion illness’, often occurs around 10 to 14 days after infection.
Seroconversion illness can have a range of symptoms, including:
- sore muscles and joints
- sore throat
- swollen lymph glands in the neck, underarm or groin areas
After the initial illness, people with HIV infection usually have no other symptoms. However, the virus remains in the body.
Why do some people with HIV infection develop AIDS?
Over time, untreated HIV infection damages the immune system and makes it more difficult to fight infections and cancers.
Before there were effective treatments for HIV infection, all infected people went on to develop AIDS within about 10 years. Today, people with HIV who take effective treatment are unlikely to develop AIDS and will have a near-normal life expectancy. This is because these medicines keep the amount of virus in their blood (‘viral load’) under control and protect the immune system.
What are the effects of AIDS?
A weakened immune system increases the risk of developing other conditions. These include:
- infections such as tuberculosis (TB), cytomegalovirus, candidiasis, cryptococcal meningitis, toxoplasmosis and cryptosporidiosis
- cancers, such as Kaposi sarcoma and lymphoma
- wasting syndrome (weight loss, often with fever and diarrhoea)
- neurological problems
- kidney disease
How do people become infected with HIV?
HIV is in the blood, semen, vaginal fluid and breast milk of an infected person. It can be spread by exposure to these body fluids by:
- unprotected anal or vaginal sex without a condom
- sharing drug-injecting equipment
- tattooing, piercing and other procedures with unsterile needles or equipment
- transmission from mother to baby during pregnancy, childbirth or breastfeeding
- oral sex, although this is rare
- healthcare workers receiving 'needlestick injuries'
It is important to remember that HIV is not spread through activities such as kissing, sharing cups and cutlery, normal social contact, toilet seats or mosquitoes.
You are at higher risk of HIV infection if:
- you are a man, a transgender woman or a person who identifies as gender diverse who has sex with men
- you have sex or share needles with someone else at risk of HIV
- you share sex toys
- you have sex with people from countries with a high rate of HIV infection (including sub-Saharan Africa, the Caribbean, Cambodia, Thailand, Burma and Papua New Guinea)
- you inject illegal drugs and share needles
- you have had tattoos or other piercings overseas using unsterile equipment
- you have a sexually transmitted infection (STI). People can be infected with several different STIs at the same time. Having an STI can make it easier to become infected with HIV and pass it on to sexual partners.
- you have had a blood transfusion in a country where the blood supply is not safe (blood is very safe in Australia)
Some people are at a higher risk of HIV infection because they are exposed to more people with HIV infection or engage in more high-risk behaviour. These include:
- Aboriginal or Torres Strait Islander people
- people with a history of imprisonment
- people who use drugs (even if these are not injected)
- people who have received care in healthcare settings where there may be poor infection control practices
- people from countries with a high rate of HIV infection
When should I get tested for HIV?
If you think you could have HIV or are at risk of HIV, talk to your doctor or sexual health clinic about having a test. Some people at high risk need to be tested regularly.
You should get tested for HIV if:
- you have had unprotected sex (vaginal or anal) with a partner whose HIV status is unknown or who has HIV but does not have a measurable amount of virus in their blood (called an ‘undetectable viral load’)
- you have had unprotected sex (vaginal or anal) with a person from a country that has high rates of HIV infection
- your sexual partner has recently travelled to a country that has high rates of HIV infection and may have had unprotected sex there
- you have had unprotected sex with a sex worker in Africa, Eastern Europe, Southeast Asia or Papua New Guinea
- you have ever shared injecting equipment
Early diagnosis is important and can improve the long-term course of the illness.
It is a good idea to talk to your doctor or sexual health clinic about other STIs at the same time.
Your information will be kept confidential unless there are major concerns for your safety or the safety of others. HIV is a notifiable disease, which means laboratory staff need to inform the government about new cases, but this information is also confidential.
How is HIV diagnosed?
Your doctor or sexual health clinic can order a blood test for HIV.The blood is sent to a laboratory, and the results can take a few days.
Rapid HIV tests
Your doctor may use a rapid test, which involves either a pinprick of the finger or saliva. This can give you a result within 10 to 20 minutes, but it will always need to be confirmed by laboratory tests.
Using the same technology as a rapid HIV test, this is a finger-prick test you can do at home or anywhere you feel comfortable. The result takes less than 15 minutes.
There is only one test approved by the Therapeutic Goods Administration (TGA) in Australia: the Atomo HIV Self-Test. It’s important to only use HIV self-tests approved by the TGA, so you know that the test is accurate and safe to use.
If you get a positive result, you need to see your doctor for further testing to confirm the result.
Whatever type of test you have, it can take up to 24 days after exposure (sometimes longer) for blood to show positive for infection with HIV.
This means that you could get a negative result when you actually have an HIV infection. This is known as a ‘false negative’. So, you may need more than one test over time to know for sure whether you have HIV.
It is important to use safe sex and safe injecting practices while waiting for the test results. Maintaining these practices after testing, even if you get a negative result, will reduce your risk of future exposure and infection.
How is HIV treated?
There is no vaccine or cure for HIV infection. However, there are effective treatments that can prevent the transmission of HIV and the progression to AIDS, and help ensure a near-normal life expectancy.
These treatments are known as antiretroviral therapy (ART). They stop the virus from reproducing itself, which leads to a lower viral load. The treatment involves a combination of drugs used together.
HIV-positive people who take ART daily — exactly as prescribed — and achieve (and maintain) an undetectable viral load can’t sexually transmit the virus to an HIV-negative partner.
Thanks to the improvements in treatment, HIV infection is now a manageable chronic disease for many people in countries like Australia.
How do I protect myself from getting infected with HIV?
The best way to prevent HIV infection is to:
- use condoms and a water-based lubricant for anal and vaginal sex
- never share needles, syringes or other injecting equipment
- make sure all tattooing, piercing and other procedures use sterilised equipment
PrEP (pre-exposure prophylaxis is a daily pill for people who are at high risk of getting HIV. It is highly effective at preventing HIV infection, but it does not stop you from getting other STIs.
Daily PrEP is recommended for all people who are at risk of HIV infection.
PrEP can also be used only at times you are likely to be exposed (known as ‘on demand’), rather than every day, but this is not suitable for everyone and its effectiveness is still being tested.
You can talk to your doctor or sexual health clinic about PrEP.
Medications can sometimes prevent HIV from infecting a person who has been exposed. This is known as PEP (post-exposure prophylaxis). It involves taking HIV medications for 4 weeks after exposure. It is best to start PEP as soon as possible, and within 72 hours (3 days) of exposure.
Some doctors can provide PEP. Otherwise, you can get PEP by going to a hospital emergency department.
You can find out more about PEP by talking to a doctor or calling a HIV PEP hotline in your state or territory. You can call healthdirect on 1800 022 222 or visit the Get PEP website for details on local PEP services across all states and territories.
Needle and syringe programs (NSPs)
Needle and syringe programs provide clean needles or syringes to people who inject drugs, reducing the risk of the transmission of HIV and other blood-borne diseases such as hepatitis B and hepatitis C. This is sometimes referred to as ‘needle exchange’.
The types of NSP outlet vary, from participating pharmacies to vending machines. Find an NSP in your state or territory:
- Australian Capital Territory
- New South Wales
- Northern Territory
- South Australia
- Western Australia
You can also find a local needle and syringe program using the healthdirect Service Finder. Select ‘By name’ and type ‘needle’ into the search bar.
How do I avoid passing HIV on to someone else?
If you are infected with HIV, the best way to prevent spreading HIV infection to others is to:
- take your medication as prescribed — there is a very low risk of passing on HIV if your own infection is under control (this is a called an ‘undetectable viral load’)
- use condoms and a water-based lubricant for anal and vaginal sex
- never share needles, syringes and other injecting equipment
If you have HIV infection, you are expected to notify anyone who is at risk of exposure from you:
- Tell people you have had sex or taken drugs with (contact tracing). Your doctor can help you decide who may be at risk and help you to contact them either personally or anonymously.
- Tell anyone you intend to have sex with about your HIV status (even when you use a condom). This is required by law in some states.
If you are pregnant, talk to your doctor about starting antiretroviral treatment to prevent the infection passing to the baby during pregnancy, childbirth or breastfeeding. Read more about HIV and pregnancy.
Living with HIV
If you have HIV or AIDS, it is very important to stick to your treatment plan. Take precautions so you don't infect anyone else.
You can stay healthy by following a nutritious diet, and avoiding raw meat and eggs. This is because foodborne illnesses are more likely to be severe or last longer in people with HIV, since HIV damages the immune system.
So, it’s also important to avoid animals that could cause infections, including cats and birds. Be very thorough about washing your hands and maintaining good hygiene.
Ensure you're up-to-date with your vaccinations.
For advice on living with HIV, visit the Australian Federation of AIDS Organisation (AFAO) website.
Resources and support
- Ending HIV
- ACON — an NSW-based health organisation specialising in HIV prevention, HIV support and lesbian, gay, bisexual, transgender and intersex (LGBTI) health
- Australian Federation of AIDS Organisation (AFAO)
- National Association of People with HIV Australia
- Youth Solutions — for HIV, hepatitis and sexual health and support services
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Last reviewed: November 2021