HIV/AIDS Information

Revisions downward of UNAIDS estimation of global HIV numbers resulted from advances in the methodology of estimations of HIV epidemics applied to an expanded range of country data. This has resulted in substantial changes in estimates of numbers of persons living with HIV worldwide.

The single biggest reason for this reduction was the intensive exercise to assess India’s HIV epidemic, which resulted in a major revision of that country’s estimates.

It is emphasized that these differences between estimates published in 2006 and those published in 2007 result largely from refinements in methodology, rather than trends in the pandemic itself.

However, the methodological revisions have been applied retrospectively to all earlier HIV prevalence data, so that the estimates of incidence, prevalence and mortality from earlier years in the current report allow an assessment of trends over time.

HIV/AIDS at a glance

In 2006, it is estimated that 33.2 million people in the world are living with the human immunodeficiency virus (HIV), the highest level ever.

In many regions of the world, HIV infections are heavily concentrated among young people aged 15-24 years, accounting for 40 per cent of new infections in 2006. However, the situation in Australia is quite different where newly acquired HIV infections occur most commonly in men aged in their mid 30s and in women aged in their late 20s.

Sourced from

2007 UNAIDS Epidemic Update 2007, Joint United Nations Programme on HIV/AIDS and the World Health Organisation, 2007
www.unaids.org

2007 AIDS Epidemic Update, Joint United Nations Programme on HIV/AIDS (UNAIDS) and the World Health Organisation (WHO), 2007
http://data.unaids.org/pub/EPISlides/2007/2007_epiupdate_en.pdf

2007 Annual Surveillance Report: HIV/AIDS, Viral Hepatitis and Sexually Transmissible Infections in Australia, National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, 2007
http://www.med.unsw.edu.au/nchecr

Scope of the global pandemic

The number of people living with HIV continues to rise due to population growth and, more recently, the life-prolonging effects of antiretroviral therapy.

Sub-Saharan Africa remains by far the worst affected region of the world, with 22.5 million people living with HIV at the end of 2006. Just under two thirds of all people living with HIV are in sub-Saharan Africa, as are more than half of all women living with HIV.

Among notable new trends are recent declines in national HIV prevalence among young pregnant women in two sub-Saharan African countries, Kenya and Zimbabwe, urban areas of Burkina Faso and similarly in Haiti. This decline in prevalence has occurred alongside indications of significant behavioural change – including increased condom use, fewer partners and delayed sexual debut.

HIV prevalence is increasing in some countries, notably China, Indonesia, Papua New Guinea and Vietnam and there are signs of HIV outbreaks in Bangladesh and Pakistan. The AIDS epidemic is affecting women and girls in increasing numbers. Globally, just under half of all people living with HIV are female.

In 2007, 15.4 million women are living with HIV globally. In Sub-Saharan Africa, women are infected more often and earlier than men. 61% of people living with HIV/AIDS in sub-Saharan Africa are women. However, in Eastern Europe, Central Asia and Latin America, young men are more likely to be infected than young women, although this is changing as HIV increasingly affects the general population.

Sourced from

2007 AIDS Epidemic Update, Joint United Nations Programme on HIV/AIDS (UNAIDS) and the World Health Organisation (WHO), 2007
http://data.unaids.org/pub/EPISlides/2007/2007_epiupdate_en.pdf

Q&A on HIV/AIDS Estimates, Joint United Nations Programme on HIV/AIDS (UNAIDS), 2007
http://data.unaids.org/pub/EPISlides/2007/071118_qa_methodology_backgrounder_en.pdf

Global AIDS response

There has been an enormous change in the global HIV/AIDS response since 2001. HIV resources increased annually by an average of US$1.7 billion between 2001-2004 and US$266 million between 1996 and 2001. Available funding in 2005 reached US$8.3 billion. Access to treatment has also increased for people in low and middle income countries. In 2001, 240,000 people received antiretroviral therapy, compared with 1.3 million people in 2005.

Sourced from

2006 Report on the Global AIDS epidemic, Joint United Nations Programme on HIV/AIDS (UNAIDS), 2006
http://www.unaids.org/en/HIV_data/2006GlobalReport/default.asp

HIV/AIDS in Australia

In Australia, at December 2006, 26,267 people had been diagnosed with HIV infection and 10,125 people with AIDS. A cumulative total of 6,723 deaths had been attributed to HIV/AIDS.

The annual number of AIDS diagnoses in Australia declined from 672 in 1996 to 209 in 2001, and has remained relatively stable over the past four years at around 240 diagnoses. The decline in the number of AIDS diagnoses in 1996-2001 was due to the fall in HIV incidence that took place in the mid 1980s and to the use, since mid 1996, of effective antiretroviral treatment of HIV infection.

Transmission of HIV continues to be mainly through sexual contact between men, which was reported in more than 87% of cases of newly acquired infection diagnosed in 2001 to 2005.

Number of diagnoses of HIV infection and AIDS in Australia :



Newly diagnosed HIV infection in Australia, including diagnoses of newly acquired HIV infection, by year :



Sourced from

2006 Annual Surveillance Report: HIV/AIDS, Viral Hepatitis and Sexually Transmissible Infections in Australia, National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, 2006
http://www.med.unsw.edu.au/nchecr

What is HIV?

HIV stands for human immunodeficiency virus. It is primarily transmitted in blood, semen and vaginal fluids via unprotected sex or sharing injecting equipment. HIV belongs to a group of viruses called retroviruses known for their capacity to copy their genetic blueprint onto the genes of a person’s cells. HIV is the virus that can cause AIDS.

What is AIDS?

Acquired immune deficiency syndrome (AIDS) is not a single disease. It is a spectrum of conditions that occur when a person’s immune system is seriously damaged after years of attack by HIV. The terms HIV and AIDS are not interchangeable. It is important to remember that a person who is infected with HIV does not necessarily have AIDS. However, all people with AIDS have HIV.
HIV damages the body’s immune system and renders the body vulnerable to other diseases and infections – its symptoms are most commonly similar to those of any chronic viral infection. During advanced stages of HIV infection, a person may develop any of a number of opportunistic infections considered to be AIDS defining illnesses.

Who does HIV affect?

Worldwide, HIV infection occurs mainly through heterosexual contact. Transmission in Australia continues to be mainly through sex between gay and other homosexually active men. In 2002-2006, a history of male homosexual contact was reported in 69% of cases of newly diagnosed HIV infection. Among cases of newly acquired HIV infection, male homosexual contact was reported in 88%, injecting drug use among women and heterosexual men in 1%, heterosexual contact only in 8%, and in 3% of cases, exposure to HIV remained undetermined.

Sourced from

2007 Annual Surveillance Report: HIV/AIDS, Viral Hepatitis and Sexually Transmissible Infections in Australia, National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, 2007
http://www.med.unsw.edu.au/nchecr

When was HIV first detected?

Antibodies to HIV have been detected in blood samples dating back to 1959. In 1981 the US Centres for Disease Control published the first scientific paper on the epidemic in a report of a rare cancer, Kaposi’s sarcoma, detected in a small number of gay men. HIV was first isolated in Paris in 1983 by Dr Luc Montagnier.

How is HIV detected?

HIV is detected by an HIV antibody test. It is incorrect to call it an ‘AIDS test’ because the test cannot detect AIDS, but instead detects the antibodies that are produced as a result of HIV infection. It can take up to three months for someone’s immune system to produce antibodies to HIV. This is called the ‘window period’. An HIV antibody test performed during this window period could be negative even though the person may be infected. There are now special blood tests (nucleic acid amplification) which can detect HIV infection during the window period.

What does HIV positive mean?

A person who has a positive HIV antibody test can be referred to as being ‘HIV positive’.

Treatments are not a cure

Sometimes, combination antiretroviral therapies are written about as if they are a cure for HIV. It is important to recognise that so far, there is no cure for HIV and it cannot be eradicated by any available drug. People who are on these drugs are still living with HIV. People living with HIV and AIDS continue to experience a range of health issues, from minor to life threatening. There are currently no vaccines available for HIV or AIDS and the treatments help with the symptoms of HIV and AIDS but do not cure them.

How is HIV transmitted?

The ability of HIV to live outside the body is very limited and therefore HIV is not particularly easy to transmit. It is a communicable disease, but it is not contagious like air-borne viruses such as influenza. HIV cannot be transmitted by hugging, shaking hands, coughing or sneezing. Nor can it be transmitted by sharing glasses, cups or utensils.

There are three main modes of HIV transmission:

• unprotected anal and vaginal sexual intercourse;
• sharing drug injecting equipment; and
• mother to child during pregnancy, birth or breast feeding.

Blood-borne transmission

Exposure to HIV contaminated blood is another potential route of transmission. Injecting drug users who share needles and syringes are at risk of HIV infection because there is often a small amount of blood left in the syringe after injection. This type of exposure can also occur during skin piercing and tattooing procedures if equipment has not been properly sterilised after having previously being used on someone infected with HIV. Body piercing or tattooing should always be undertaken at licensed studios that use new ink pots for each procedure and disposable needles or an autoclave to sterilise equipment.

What is safe sex?

Any unprotected anal or vaginal intercourse, that is, insertive or receptive sex without the use of a condom or barrier, has the potential to transmit HIV. The risk of transmission is greater when the person also has an untreated sexually transmitted infection. There is a much lower risk of transmission through oral sex, but this risk increases when there are cuts or sores in the mouth where HIV may enter the bloodstream.

Safe sex prevents semen, pre-ejaculate, vaginal fluid or blood from coming into direct contact with the internal membranes of another person. Penetrative sex can be made safer by using a condom and water-based lubricant (lube). Condoms remain the best protection against the sexual transmission of HIV, provided they are used correctly. A water-based lubricant should always be used with condoms to prevent breakage.

Occupational exposure

For the same reason, being pricked with a contaminated needle, known as a needlestick injury, presents a small risk of transmission. In Australia there have been several cases of HIV infection among health care workers following occupational exposure to blood or body fluids, mainly through needlestick injuries. There is no recorded case of HIV being transmitted through a discarded needle in a community setting.

Mother to child

There are two main routes of HIV transmission between mother and child. One is known as perinatal infection, where a pregnant woman with HIV can transmit the virus to the foetus during pregnancy or birth. The risk of perinatal transmission can be reduced through careful management of the pregnancy and delivery. This may include the use of antiretroviral drugs, taken by an HIV positive woman during pregnancy and the birth, and given to the newborn child for six weeks.

The other mode of transmission is breastfeeding. Women with HIV should avoid breastfeeding, except in countries where water quality for bottle-feeding cannot be assured and where many mothers cannot afford formulas. In developing countries, shorter courses of antiretroviral treatments have decreased the rate of mother to child transmission.

The role of sexually transmissible infections (STIs) in the transmission of HIV

The presence of certain STIs significantly increases the risk of HIV transmission and acquisition. People infected with an STI are generally at higher risk of acquiring HIV. Increasing evidence suggests that people dually infected with both HIV and an STI are at a high risk of transmitting HIV as well as progressing more rapidly to AIDS. Many of these STIs may be asymptomatic or cause only minor symptoms. The occurrence of asymptomatic infection has important personal and public health implications in that undiagnosed infection may prolong the period of infectiousness of that individual. For this reason, in those at high risk of STIs, such as gay and other homosexually active men who have multiple partners, improved knowledge about STIs and regular testing is an important means of HIV prevention.

Harm minimisation

Harm minimisation, as evidenced through the establishment of needle and syringe programs, have been credited as one of the main reasons for Australia’s success to date in containing the HIV infection rate among people who inject drugs.

Sourced from

HIV/AIDS Media Guide, Australian Federation of AIDS Organisations Inc., Australian National Council on AIDS, Hepatitis C and Related Diseases, 2000
http://www.ancahrd.org/pubs/pdfs/mediaguide/htm

2007 Annual Surveillance Report: HIV/AIDS, Viral Hepatitis and Sexually Transmissible Infections in Australia, National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, 2007
http://www.med.unsw.edu.au/nchecr

United Nations Population Fund, July 2004
http://www.unfpa.org/hiv/index.htm

National HIV/AIDS Strategy: Revitalising Australia’s Response 2005-2008, Australian Government Department of Health and Ageing, 2005
http://www.health.gov.au/internet/wcms/publishing.nsf/Content/health-pubhlth-strateg-hiv_hepc-hiv-index.htm