HIV AIDS (Human Immune Deficiency Virus & Acquired Immune Deficiency Syndrome)

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What is HIV AIDS?

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HIV is a retrovirus that causes AIDS. HIV attacks the immune system. This system consists of cells and organs that protect the body against diseases like infections and cancer. HIV attacks the immune system through special types of white blood cell known as CD4 cells. CD4 cells play an important role in orchestrating and controlling the functions of the whole immune system.

Once HIV is in the immune system, it multiplies inside the CD4 cells, disabling and killing them in the course of the infection, and thus interfering with their normal function. The immune system gradually deteriorates until it reaches a point where it can no longer fight off any infection.

The infected person frequently gets infections and even some forms of cancer which a healthy immune system would have gotten rid of quite easily. These infections are known as opportunistic infections. HIV infection, once established, cannot be eliminated by the body or by drugs.

Who gets HIV AIDS?

According to the 2006 report on the Global AIDS Epidemic by the Joint United Nations Programme, approximately 37.2 million adults and 2.3 million children were living with HIV at the end of 2006. During 2006, some 4.3 million people became infected with HIV, and approximately 2.9 million deaths resulted from HIV/AIDS.

By 30 June 2006, 25,703 people in Australia were infected with HIV, 9,827 had AIDS and 6,621 died as a result of HIV/AIDS. NSW had the highest number of deaths, followed by Vic, QLD, WA, SA, ACT, NT and TAS.

Predisposing Factors

HIV can be transmitted through the following routes:

Unprotected sexual intercourse with an infected partner
Contact with infected blood through blood transfusion, sharing needles or syringes contaminated with infected blood by injecting drug users
Mother to child transmission (vertical transmission) during pregnancy, at birth and breastfeeding

Progression

Throughout the disease, viral load steadily increases and immunodeficiency progressively worsens (due to the decreasing CD4 count), thereby causing HIV/AIDS to manifest in stages. The World Health Organization (WHO) has categorized HIV disease into 4 stages:

Stage I (also known as primary HIV infection):

In this stage, the person has no symptoms whatsoever and may not be aware they are infected.
Stage II (also known as clinically asymptomatic stage):

This stage may last for 8-10 years with no major symptoms except for swollen glands (lymph nodes), some weight loss, mouth ulceration and mild skin and nail infections.
Stage III (also known as symptomatic HIV infection):

By this stage, the immune system is significantly affected and the infected person now begins to manifest many symptoms, such as severe weight loss, chronic diarrhoea, persistant fever, tuberculosis, severe bacterial infections (e.g. pneumonia and meningitis).
Stage IV (also known as AIDS):

The immune system is now severely damaged and the symptoms become even more severe. The person is now severely wasted, has severe recurrent bacterial infections, develops cancers such as Kaposi sarcoma, and other infections like Pneumocystis carinii pneumonia (PCP), toxoplasmosis and HIV encephalopathy.