FHI - HIV/AIDS Overview

HIV/AIDS Overview

HIV/AIDS was identified concurrently in North America, the Caribbean and East Africa in 1978. By 1999, more than 33 million people from 190 countries were HIV-positive, and 16.3 million had died of AIDS.

Although sub-Saharan Africa has two-thirds of the world's HIV infections and 84 percent of its AIDS deaths, the region accounts for just 3 percent of global AIDS spending.

HIV/AIDS: the global and African epidemics

Africa

Worldwide

People living with HIV/AIDS
23.3 million

33.6 million

AIDS deaths
13.7 million

16.3 million

Source: UNAIDS, December 1999

Sub-Saharan Africa's epidemic is best analyzed under three sub-regions: eastern, southern and western Africa. In East Africa, which has Africa's oldest epidemic, HIV was observed around Lake Victoria in 1978. With 15 percent of sub-Saharan Africa's population, this subregion has 38 percent of its HIV infections. Yet the epidemic has slowed in East Africa. It is spreading much faster in southern Africa, where it was first observed in the early 1980s. In fact, in 1993, the World Health Organization stated that the global HIV epicenter had moved from eastern to southern Africa. The turning point was a 1993 survey showing that 37 percent of pregnant women in Francistown, Botswana, were infected with HIV. Southern Africa now has over 40 percent of sub-Saharan Africa's HIV infections and the world's seven most-affected countries: Swaziland, Zimbabwe, Botswana, Zambia, Malawi, South Africa and Namibia. HIV entered West Africa in the early 1980s, but fortunately has spread more slowly there. Fewer than 18 percent of HIV infections are in West Africa, Africa's most populous region.

Estimates of adult HIV prevalence in Zimbabwe, Zambia and South Africa are based on data from women attending antenatal clinics, which approximates data on the sexually active adult population. Zimbabwe has one of the world's highest adult prevalence rates (26 percent), exceeded only by Swaziland's (33 percent) and surpassing Botswana's (25 percent). A fifth of Zambia's and South Africa's adults have HIV.

HIV in Zimbabwe, Zambia and South Africa

Country
Estimated Adult HIV Prevalence

Estimated Adults and Children with HIV

Zimbabwe
26%

1,500,000

Zambia
20%

1,009,000

South Africa
23%

5,000,000

Sources: National AIDS Control Program, Zimbabwe; Ministry of Health/Central
Board of Health, Zambia; National Department of Health, South Africa

Zimbabwe's HIV epidemic

In the capital, Harare, 38.4 percent of 1995 antenatal patients had HIV. Disaggregation of the data by age showed that 22 percent of 15-year-olds, 25 percent of 18-year-olds, 29 percent of 21-year-olds and 41 percent of 24-year-olds were infected. Antenatal HIV prevalence rates in the other cities of Mutare, Gweru and Bulawayo ranged from 29 percent to 38 percent.

Rates in towns near major highways, trading centers, borders, mines and plantations are even higher. For example, 70 percent of 1995 antenatal patients in the sugar plantation town of Chiredzi, 67 percent of 1995 antenatal patients in the highway town of Rusape, and 59 percent of 1996 antenatal patients in the border town of Beitbridge, had HIV.

It is unclear whether Zimbabwe's epidemic has peaked, as the quality and comparability of annual surveys is limited, and declines in some sites are offset by increases elsewhere.

Zambia's HIV Epidemic

The 1998 antenatal survey found HIV prevalence rates of 27 percent in Zambia's major cities. As in Zimbabwe, rates are very high along major highways and in trading centers and border, plantation and mining towns. The 1998 survey reported rates of 31 percent in the border town of Livingstone and 27 percent in the border town of Chipata, the trading town of Mongu and the highway town of Kabwe.

A Ministry of Health expert group estimated that provincial adult HIV prevalence was 26 percent in Lusaka, 23 percent in the Copperbelt and 19 percent in Northern Province. National adult HIV prevalence is estimated to be 20 percent, which means that more than 1 million adults have HIV. HIV rates are twice as high in urban areas as in rural areas.

Although national prevalence levels are stable, sentinel surveillance results show a downward trend in prevalence among 15- to 19-year-olds, particularly in urban areas. This trend is most notable in Lusaka, where HIV prevalence dropped from 28 percent in 1993 to 15 percent in 1998. Many believe such declines in prevalence probably correspond to reductions in new HIV infections among late teens, and that lower incidence will eventually be reflected in an overall drop in HIV prevalence. Others believe that the data should be interpreted more cautiously until enough time has passed to evaluate the impact of this trend on the epidemic in Zambia.

South Africa's HIV Epidemic

South Africa has the world's fastest growing HIV epidemic. National HIV prevalence rates from 1990 to 1998 illustrate how rapidly the epidemic is growing, from less than one percent in 1990 to more than 22 percent in 1998 (Figure 1).

South Africa's HIV epidemic has clear provincial and regional trends. Provincial data show that HIV prevalence is higher in the north and east, and lower in the south and west. HIV is also lower in the deeply rural Northern (12 percent) and Eastern Cape (16 percent) provinces. However, HIV grew rapidly in these provinces from 1997 to 1998, by 40 percent in Northern Province and 26 percent in the Eastern Cape.

Within each province, HIV rates are highest in highway, border, mining, plantation, migrant and informal settlement areas. Thus, rates are highest in KwaZulu's Empangeni highway and plantation area, Mpumalanga's Secunda highway and mining town, Gauteng's Carletonville mining town, Free State's Welkom mining town, the North-West's Rustenburg mining town, and Northern Province's Messina highway and border town.

HIV is growing fastest among younger age groups. From 1997 to 1998, HIV grew by 65 percent among youth under 20, by 32 percent among 20- to 24-year-olds and by 48 percent among 25- to 29-year-olds.

See Also:

HIV/AIDS Overview