HIV/AIDS Information
What is HIV?
Human Immunodeficiency Virus (HIV) is the virus that causes Acquired Immune Deficiency Syndrome (AIDS).
When a person is infected with HIV, the virus begins to attack their immune system, causing it to weaken or become immune deficient. The longer a person has HIV, the more damaged their immune system can become. This process leaves a person prone to certain infections and cancers.
There are two major types of HIV, called HIV-1 and HIV-2. The most common and broadly distributed HIV type is HIV-1, which accounts for most of the infections worldwide, including in Australia.
What is AIDS?
AIDS is the advanced stage of HIV infection, which occurs when an HIV-infected person’s immune system has been damaged after years of attack by the virus. It is diagnosed when an HIV-positive person develops one or more specific infections or certain cancers, known as AIDS-defining conditions, or when the number of specific immune system cells, known as T-cells or CD4 cells, falls to a very low level.
Many of the infections resulting in serious illness in people with AIDS are caused by organisms or ‘bugs’ that are quite common and would normally not affect someone with a strong, healthy immune system. A person with HIV infection becomes susceptible to these illnesses because their immune system is unable to fight the ‘bugs’ effectively. These infections take advantage of a weakened immune system to cause illness and are known as opportunistic infections.
AIDS-defining conditions can include particular forms of pneumonia, brain disease and cancer, as well as infections that cause significant weight loss, serious eye conditions or diarrhoea. A person can recover from these illnesses and become well again, but they are still considered to have AIDS. There is no way to predict when or whether a HIV positive person might develop AIDS.
How can you protect yourself?
Safe sex
In order to avoid HIV and other infections spread through sex, people are encouraged to follow safe sex guidelines. Safe sex is any sex that doesn’t allow semen, vaginal secretions or blood to get inside you or your partner’s body.
Using good quality condoms properly during intercourse (anal and vaginal) greatly reduces the risk of transmitting HIV. Condoms should be used with plenty of water-based lubricant. Male condoms may be bought from supermarkets, chemists and other outlets. The female condom (Femidom) is available from family planning centres. Latex dams (or cut open condoms) are a useful way of avoiding exchanges of bodily fluid during oral/vulval or oral/anal sex.
Know your HIV status
If you think you are at risk, or have been exposed to HIV, a simple blood test can be done at your local sexual health centre or by your doctor.
Safe needle and syringe use
HIV and other infections, such as hepatitis C, can be passed on through sharing injecting equipment. It is extremely risky to share needles, syringes and other injecting equipment. The safest way to avoid infections is to not inject drugs. People who inject drugs should always use sterile needles, syringes and equipment.
Post-Exposure Prophylaxis
Post-exposure prophylaxis (PEP) is a four-week course of two or three anti-HIV drugs which may stop HIV infection becoming established. PEP must be started as soon as possible up to 72 hours after exposure to the virus through unprotected sex, sharing needles or a needlestick injury. PEP reduces the risk of HIV transmission but does not guarantee that infection will be prevented.
What are the symptoms of HIV infection?
a) Early symptoms
Some people do not have any symptoms when they first become infected with HIV, but about 70% of people develop a flu-like illness two to six weeks after exposure to the virus. Symptoms may include tiredness, fever, a rash, headache, sore throat, diarrhoea or swollen lymph glands in the neck, underarm and groin areas. These symptoms usually disappear within a week to a month and are often mistaken for another viral infection.
b) Later symptoms
People with HIV may not have any symptoms for several years, but as the immune system becomes weakened, various signs of infection may appear, including lack of energy, weight loss, frequent fevers and night sweats, diarrhoea and swollen glands. Other symptoms include persistent or frequent yeast infections (“thrush”) in the mouth or vagina, persistent cough, skin rashes or lumps.
How is HIV detected?
HIV infection is diagnosed using a simple blood test where a person’s blood sample is checked for the presence of HIV antibodies. Antibodies are produced by specific cells in the immune system that are programed to recognise and fight infections. The presence of HIV antibodies in a blood sample indicates that a person is infected with HIV, or is HIV-positive.
Most people develop antibodies within two to four weeks after exposure to HIV, but it can take up to three months for a person’s immune system to develop HIV antibodies. This is known as the ‘window period’. An HIV antibody test performed during this period can be negative even though the person may be infected. People who believe they may have been at risk of HIV infection are tested and, if negative, are tested again about three months later.
There are now special blood tests (nucleic acid amplification) which can detect the presence of HIV earlier in the window period.
Can HIV be treated?
Currently there is no vaccine or cure for HIV, but drug treatments are available which can control the virus, delay progression to AIDS, and keep HIV positive people healthy for longer. These treatments are known as combined antiretroviral therapy (CAR) or highly active antiretroviral therapy (HAART). Treatment usually involves taking three different drugs that act on the virus in different ways. There are also treatments for many of the specific illnesses associated with HIV and AIDS. Once someone begins antiretroviral treatments, they should continue to take them for life. Treatments can have side effects and people who are on treatment need to be monitored regularly by their doctors. Sometimes the virus develops resistance to the drugs and treatment may need to be changed to a different combination of drugs.
Even when treatment is working well, it does not control all of the virus so the person still has HIV in their body and can pass it on through unprotected sex and sharing injecting equipment.
How is HIV transmitted?
HIV is a fragile virus that cannot live for long outside a human body. Therefore it cannot be spread through everyday activities such as touching people and sharing kitchens, bathrooms, toilets, clothes, bed sheets, towels or swimming pools. HIV can’t be spread by pets or other animals, or insects such as mosquitoes.
For HIV to be transmitted there must be:
- large amounts of the virus present in body fluids (blood, semen, vaginal secretions, menstrual blood and breast milk); and
- a way for that fluid to move directly from the blood stream of one body into another (via needles, open or very small cuts in the vagina, anus or mouth).
The main ways HIV is spread are through:
- anal or vaginal sex without condoms;
- sharing needles and syringes when injecting drugs; and
- mother to baby during pregnancy, at birth or through breast feeding.
HIV and viral loads
When a person with HIV is on antiviral medications, the level of virus in their body fluids (known as “viral load”) may reduce to very low levels that cannot be detected by testing. Research suggests that, when the viral load is undetectable in the blood, the risk of HIV transmission is reduced but it is still possible to transmit the virus. Safe sex should still be practised regardless of the viral load.