(October 2002) In the early stages of the HIV epidemic, the highest prevalence rates were concentrated along the major transportation routes that cut across sub-Saharan Africa: through Tanzania and Uganda, around Lake Victoria into what is now the Democratic Republic of Congo, and into Côte d’Ivoire on the coast of western Africa. Infected soldiers, truck drivers, migrant workers, affluent businessmen, and commercial sex workers spread the disease to their families and communities. By 1986, between 5 percent and 10 percent of adults in Uganda and Burundi were infected with HIV, as were 1 percent to 5 percent of adults in 10 other countries. As the epidemic progressed, HIV prevalence rates increased in these countries, and the virus spread throughout the region.

By 2001, at least 5 percent of adults in nearly every sub-Saharan country were infected with HIV. Prevalence rates have reached alarming levels in southern Africa: More than 20 percent of adults in Botswana, South Africa, Zambia, Zimbabwe, and three neighboring countries had HIV in 2001. UNAIDS sees no evidence that rates have leveled off even in these high-prevalence countries, with the possible exception of Zambia. HIV prevalence among pregnant women in urban Botswana, for example, rose from 39 percent to 45 percent between 1997 and 2001, according to UNAIDS. Prevalence is even higher among younger women, suggesting that overall adult prevalence may rise further.

HIV prevalence rates have risen in most eastern African countries also, but Uganda stands out as a success story in the fight to stem the epidemic. In the 1980s, public health officials identified an epidemic of HIV in Uganda; public awareness of the disease spread as Ugandans saw increasing numbers of friends and relatives dying from AIDS. The government, along with religious and nongovernmental organizations (NGOs), launched programs to destigmatize people with AIDS and educate the public about how to avoid infection. Most programs promoted abstinence for adolescents, monogamy for adults, and safe sex for all sexually active people. Uganda’s direct approach to HIV prevention earned wide respect throughout the international health community, especially as the country’s prevalence rates appeared to decline. Among pregnant women tested for HIV in Kampala, Uganda’s capital, prevalence declined from a peak of nearly 30 percent in 1992 to 11 percent in 2000. An estimated 5 percent of Ugandan adults had HIV in 2001, down from an estimated 10 percent or more in the early 1990s.

The epidemic spread more slowly in most western African countries, except in Côte d’Ivoire. More than one-third of female sex workers tested in urban areas in Côte d’Ivoire in 1999 had HIV, according to UNAIDS.

Some researchers see West Africa poised for a surge in HIV/AIDS cases. After at least five years of relatively low and stable prevalence rates, recent surveillance data have detected sharp increases in Cameroon and parts of Nigeria, for example. In 2000, about 10 percent of pregnant women tested for HIV in Cameroon were infected; in 2001, sentinel surveillance centers reported an HIV prevalence rate of about 5 percent in Nigeria. But prevalence rates have remained low in Senegal, which appears to have staunched the epidemic through public health programs. UNAIDS has lauded Senegal’s response to HIV/AIDS as a model for other countries.

The epidemic in Africa is fueled by ignorance of the disease, lack of access to prevention, inadequate treatment and care services, and stigma and discrimination. Young African girls are dangerously undereducated about AIDS and how to protect themselves from it. UNICEF reports that more than 70 percent of adolescent girls in Somalia and more than 40 percent in Guinea-Bissau and Sierra Leone have never heard of AIDS; in Kenya and Tanzania, more than 40 percent of young girls harbor serious misconceptions about the disease and how it is transmitted. A survey conducted by Kenya’s Population Council in 2001 revealed that more than half of the women who are aware of their positive HIV status said they had not disclosed their status to their partners for fear of violence or abandonment. Because heterosexual sex is the primary mode of transmission in Africa and because young women have the highest rates of new infection, these gaps in knowledge and understanding, along with discrimination and fear, fuel the epidemic.

A number of other factors may help explain why HIV has hit Africa especially hard. Among these are the high incidence of STIs, large refugee populations, seasonal labor migration by men, the active commercial sex industry, and cultural practices that allow for multiple sexual partners. Thousands of men live away from their families for months at a time to work in gold and diamond mines in southern Africa, for example. Many seek out commercial sex workers, which favors the spread of HIV. An estimated one-third of the miners in some South African mines have HIV. When these miners return to their families, they introduce HIV into their home communities.

While Uganda, Senegal, and Zambia have shown signs of containing the epidemic, the signs from most other sub-Saharan countries suggest that HIV prevalence is likely to increase.

Peter Lamptey is president of the Family Health International (FHI) Institute for HIV/AIDS. Merywen Wigley is an associate technical officer at the FHI Institute for HIV/AIDS. Dara Carr is a technical director for health communication at PRB. Yvette Collymore is senior editor at PRB. This article is excerpted from PRB’s Population Bulletin “Facing the HIV/AIDS Pandemic” (PDF: 786KB).