Asia

Asia is now set to see the biggest Aids explosion with numbers of HIV cases expected to double by the year 2000.

Campaigning: Education can work

Cambodia is the most affected country in the region. Its health ministry estimates that 150,000 of the 11m population have HIV. Around 90% of these are thought to have caught the virus through heterosexual intercourse.

UNAIDS fear these figures are grossly underestimated.

It recently warned that one of the key contributors to the disease's spread in Asia was the prevalence of sexually transmitted disease (STDs).

People with STDs are more likely to contract the virus.

However, in different parts of the continent, as in different parts of the world, there are variations in the pattern of HIV spread.

For example, in China and Vietnam, intravenous drug use is a prime route for infection.

Latin America

In Latin America, as in the USA and Western Europe, the main communities affected by HIV are gay men and intravenous drug users.

The number of cases of people being infected through heterosexual sex is rising fast.

Africa

More than 80% of people with Aids come from Africa.

HIV rates are beginning to fall in Uganda

But some countries have had relatively low levels of infection, while others, such as Kenya, Tanzania, Zimbabwe and Uganda have suffered greatly.

In Zimbabwe, which with Botswana has the highest incidence of Aids, life expectancy is likely to fall from 61 to 39 by the year 2010 because of Aids.

One in four people in the country is HIV positive.

Southern Africa, which is expected to see similar levels of HIV as were seen earlier in Eastern Africa, is only just beginning to tackle the problem.

It has a relatively well developed road system as well as a high level of migrant workers, allowing the disease to spread rapidly.

Many men working in the mines have to live most of the year away from home and there is a high use of prostitutes.

The end of apartheid may help the spread of HIV because it allows freer movement around the country.

The West: Managable crisis?

Aids also shows graphically the inequalities in world health.

While in the West, the presence of strong drug combinations has led to HIV becoming virtually a manageable disease, the situation is totally different in developing countries where drug treatments are too expensive.

In many places people have no access to voluntary HIV testing and counselling.

Even when these services are offered, many do not want to know or acknowledge their HIV status because of the stigma attached to Aids.

Prevention

But UNAIDS says education and prevention has worked.

Uganda was hit early on in the pandemic and has organised huge health campaigns as a result.

UNAIDS say these are beginning to have an effect and the numbers of people infected are beginning to fall.

Other factors influencing the spread of the disease include cultural attitudes to sex and the fact that governments have many other problems which demand urgent attention.