Sub-Saharan Africa has the highest HIV prevalence in the world. The region is now home to 29.4 million people living with HIV/AIDS. Approximately 3.5 million new infections occurred there in 2002, while the epidemic claimed the lives of an estimated 2.4 million people in the past year. Ten million young people (aged 15-24) and almost 3 million children under the age of 15 are living with HIV.

Rampant epidemics are under way in southern Africa where, in four countries, national adult HIV prevalence has risen higher than thought possible, exceeding 30%: Botswana (38.8%), Lesotho (31%), Swaziland (33.4%), and Zimbabwe (33.7%).

Elsewhere, in west and central Africa, the relatively low adult HIV prevalence rates in countries such as Senegal (under 1%) and Mali (1.7%) are shadowed by more ominous patterns of growth. HIV prevalence is estimated to exceed 5% in eight other countries of west and central Africa, including Cameroon (11.8%), Central African Republic (12.9%), Côte d'Ivoire (9.7%), and Nigeria (5.8%). The sharp rise in HIV prevalence among pregnant women in Cameroon (more than doubling to over 11% among those aged 20-24 between 1998 and 2000), shows how suddenly the epidemic can surge.

Against this background, it is too easily forgotten that the vast majority of Africans--more than 90%--have not acquired HIV. Enabling them to remain HIV-free is a massive challenge, with the protection of young people a priority. There are new, hopeful signs that the epidemic could eventually be brought under control.

In South Africa, for pregnant women under 20, HIV prevalence rates fell to 15.4% in 2001 (down from 21% in 1998). This, along with the drop in syphilis rates among pregnant women attending antenatal clinics (down to 2.8% in 2001, from 11.2% four years earlier) suggests that awareness campaigns and prevention programs are bearing fruit. A major challenge now is to sustain and build on such tentative success, not least because HIV infection levels continue to rise among older pregnant women.

A decline in HIV prevalence has also been detected among young inner-city women in Addis Ababa in Ethiopia. Infection levels among women aged 15-24 attending antenatal clinics dropped from 24.2% in 1995 to 15.1% in 2001 (however, similar trends were not evident in outlying areas of the city, nor is there yet evidence of them occurring elsewhere in the country).

Uganda continues to provide evidence that the epidemic does yield to human intervention. HIV infection levels appear to be on the decline recently in several parts of the country--as shown by the steady drop in HIV prevalence among 15-19-year-old pregnant women. Trends in behavioural indicators are in line with this apparent decline in HIV incidence. Condom use by single women aged 15-24 almost doubled between 1995 and 2000/2001, and more women in that age group delayed sexual intercourse or abstained entirely.

HIV/AIDS represents a severe development crisis in sub-Saharan Africa. Even if exceptionally effective prevention, treatment and care programmes take hold immediately, the scale of the epidemic means that the human and socioeconomic toll will be massive for many generations. The current food crisis in southern Africa is, most likely, linked to the HIV/AIDS epidemic's toll on the lives of young, productive adults in the region.

In the absence of massively expanded prevention, treatment and care efforts, the AIDS death toll on the continent is expected to continue rising before peaking around the end of this decade. The worst of the epidemic's impact will be felt in the course of the next decade and beyond.

Nineteen African countries have set up national HIV/AIDS councils or commissions at senior levels of government, and local responses are growing in number and vigour. Across the region, 40 countries have completed national strategic AIDS plans--evidence of their determination to reach the targets outlined in the Declaration of Commitment on HIV/AIDS. Also encouraging is the active involvement of regional bodies, such as the Economic Commission for Africa, the Africa Union, and the Southern African Development Community, in tackling HIV/AIDS as a development issue.

Only a tiny fraction of the millions of Africans in need of antiretroviral treatment are receiving it. Many millions are not receiving medicines to treat opportunistic infections, either.

Relatively prosperous Botswana has become the first African country to adopt a policy to ultimately make antiretrovirals available to all citizens who need them. However, comparatively few people (approximately 2,000) are currently benefiting from this commitment.

In addition, a handful of companies (such as AngloGold, De Beers, Debswana and Heineken) have announced schemes to provide antiretrovirals to workers and some family members. These are valuable efforts. Measured against the extent of need, however, they are plainly inadequate.