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Section 2: HIV/AIDS

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AIDS (Acquired Immuno-Deficiency Syndrome) is now the leading infectious epidemic disease in the world. It is the leading epidemic killer, with WHO (World Health Organisation) estimating 5 million AIDS deaths in 2003, and that number is still growing each year.

It is certainly the most talked and written about disease, largely in terms of 'crisis'.

AIDS is referred to as a 'pandemic'. This emphases its global spread. In fact, the World Health Organisation (WHO) has called AIDS 'a global crisis' and 'a global explosion'.  

AIDS is often compared to the 'Black Death', because of the number of people affected. The bubonic plague of the 14th century killed between one-quarter and one-third of the population of Europe over the period of a few years. It devastated the economy and society at the time.

AIDS is considered to be so serious for two main reasons:

1. Almost all people who contract AIDS will die as a result: i.e. in technical language, there is an almost 100% case fatality

2. Most (but not all) people who contract AIDS do so as a result of their own or their partner's behaviour or personal lifestyle decisions. Or, in the case of mother-to-child transmission, their mother's behaviour. This will occur as a result of their sexual activity, whether heterosexual (opposite sex) or homosexual (same sex), or as a result of drug injections using contaminated needles. People may also be infected through blood transfusions (for more information about this see the biology page).

AIDS can therefore be thought of as a behavioural disease, and everyone is at risk, although some people more than others.

To manage and control AIDS it is important to understand both the origins and impacts of the disease in terms of biomedical science and also the social and behavioural aspects of the disease.

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Understanding AIDS

AIDS first became known to science only in 1981 - less than a generation ago. In less than 25 years it has grown to major prominence in all parts of the world. It is still growing in many areas where it is at its most serious, e.g. in Africa.

It is also spreading in areas where it has been less serious. For example in the two countries with the largest populations - China and India (between them they have 42% of the world's population).

Enormous efforts are being devoted by medical scientists and social scientists to try to understand AIDS and to find a way to control it and manage its serious economic and social consequences. However, the AIDS epidemic is often referred to in apocalyptic terms such as 'out of control', 'unmanageable', 'catastrophic' or 'the world's gravest problem'.

The material presented in the HIV/AIDS pages of this website will place some of the threatening and doom-laden language and images into a more balanced perspective. It includes discussion of both social and medical aspects of the disease to work towards a full understanding of the AIDS epidemic.

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Data: A word of warning

Before reading about AIDS, it is important to recognise that there may be some problems in getting accurate information.

UNAIDS and other organisations try to provide estimates of the number of people infected with HIV/AIDS (prevalence). These estimates are often based on AIDS deaths and other associated estimates, such as the number of orphans.

These estimates are helpful and are widely used, but they do come with a warning about accuracy. The quantity and quality of the primary data sources is often insufficient because:

•  AIDS is not normally recognised as a cause of death. Though people with AIDS have high mortality, they normally die of some other infection that will be recorded as cause of death (for more information on this see the Biology pages).

•  In Africa in particular most of those who die of AIDS will not have been given a formal diagnosis - that is they won't have had medical tests for HIV/AIDS.

•  It is impossible to test everyone. Data mainly comes from estimates based on studies which test small groups of people in certain places. Different ways of estimating the prevalence of HIV and AIDS often come up with different answers. There is no way of telling which one is nearest to the actual number.

•  There is still a lot of prejudice against people with HIV and AIDS in many countries. This means that coming for a blood test is difficult. And when no cure or therapy can be offered, there may be a disadvantage in even knowing one's sero-status.

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Click here to test what you've learnt from this page.
(Note: for the multiple choice questions you need to click reset before you try again.)

1. What does HIV stand for?

Homosexual Intensity Virus
Human Immuno Deficiency Virus
Has Incurable Virus

2. What does AIDS stand for?

Acquired Immuno-Deficiency Syndrome
Auto-Immuno Deficiency Syndrome
Associated Incurable Death Status

3. True or false? Globally, more than 4 million people currently die of AIDS each year?
4. Which of these is the reason why AIDS has been likened to the black death?
It has a similar cause
It has similar symptoms
It has a similar immediate effect
It has a similar long-term effect

5 . Which FOUR of these are reasons for the lack of accurate data on HIV/AIDS prevalence?

Click the four you think they are and then click submit to find out if you are correct. Unless you get all four right it will tell you you're wrong. Click reset to try again.

Lack of blood testing
Individuals are reluctant to admit to being HIV+
Testing is inaccurate
AIDS is not an immediate cause of death
Most people who die of AIDS don't die in hospitals under medical supervision



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Understanding Epidemics