Epidemiology HIV/AIDS

Main article: AIDS pandemic

Estimated prevalence of HIV among young adults (15-49) per country at the end of 2005.

UNAIDS and the WHO estimate that AIDS has killed more than 25 million people since it was first recognized in 1981, making it one of the most destructive pandemics in recorded history. Despite recent improved access to antiretroviral treatment and care in many regions of the world, the AIDS pandemic claimed an estimated 2.8 million (between 2.4 and 3.3 million) lives in 2005 of which more than half a million (570,000) were children.^[3]

In 2007, between 30.6 and 36.1 million people were believed to live with HIV, and it killed an estimated 2.1 million people that year, including 330,000 children; there were 2.5 million new infections.^[125]

Sub-Saharan Africa remains by far the worst-affected region, with an estimated 21.6 to 27.4 million people currently living with HIV. Two million [1.5–3.0 million] of them are children younger than 15 years of age. More than 64% of all people living with HIV are in sub-Saharan Africa, as are more than three quarters of all women living with HIV. In 2005, there were 12.0 million [10.6–13.6 million] AIDS orphans living in sub-Saharan Africa 2005.^[3] South & South East Asia are second-worst affected with 15% of the total. AIDS accounts for the deaths of 500,000 children in this region. South Africa has the largest number of HIV patients in the world followed by Nigeria.^[126] India has an estimated 2.5 million infections (0.23% of population), making India the country with the third largest population of HIV patients. In the 35 African nations with the highest prevalence, average life expectancy is 48.3 years—6.5 years less than it would be without the disease.^[127]

The latest evaluation report of the World Bank's Operations Evaluation Department assesses the development effectiveness of the World Bank's country-level HIV/AIDS assistance defined as policy dialogue, analytic work, and lending with the explicit objective of reducing the scope or impact of the AIDS epidemic.^[128] This is the first comprehensive evaluation of the World Bank's HIV/AIDS support to countries, from the beginning of the epidemic through mid-2004. Because the Bank aims to assist in implementation of national government programmes, their experience provides important insights on how national AIDS programmes can be made more effective.

The development of HAART as effective therapy for HIV infection and AIDS has substantially reduced the death rate from this disease in those areas where these drugs are widely available. This has created the misperception that the disease has vanished. In fact, as the life expectancy of persons with AIDS has increased in countries where HAART is widely used, the number of persons living with AIDS has increased substantially. In the United States, the number of persons with AIDS increased from about 35,000 in 1988 to over 220,000 in 1996 and 312,000 in 2002^[129]

In Africa, the number of MTCT and the prevalence of AIDS is beginning to reverse decades of steady progress in child survival. Countries such as Uganda are attempting to curb the MTCT epidemic by offering VCT (voluntary counselling and testing), PMTCT (prevention of mother-to-child transmission) and ANC (ante-natal care) services, which include the distribution of antiretroviral therapy.

HIV Prevalence

Traditionally, HIV prevalence estimates have been derived from data from sentinel surveillance systems that monitored HIV rates among pregnant women and high-risk populations using statistical systems. By collecting blood for HIV testing from representative samples of the population of men and women in a country, MEASURE DHS can provide nationally representative estimates of HIV rates.

Both sentinel surveillance and population-based data sources of prevalence data can and should be used to track HIV epidemics. Population-based testing can only be undertaken every 3 to 5 years in most countries, because of the size and expense of the surveys. Sentinel surveillance testing is often reported annually, and provides a good benchmark for measuring progress over short time periods.

In addition, population-based testing is dependent on the population’s willingness to be voluntarily tested for HIV. In cases where the characteristics of those who agreed to be tested are different than those who refused testing, bias may result. The current DHS reports with HIV testing include analysis of non-response bias.

MEASURE DHS has conducted population-based HIV testing since 2001. The MEASURE DHS testing protocol provides for anonymous, informed, and voluntary testing of women and men. All respondents receive referrals for free testing, counseling, and educational materials.

The linkage of DHS HIV test results to the full DHS survey record (without personal identifiers) allows for an in-depth analysis of the sociodemographic and behavioral factors associated with HIV infection. Datasets showing test results and variables to link them to other findings from the DHS or AIS are available for research and study