HIV epidemiology and surveillance
The human immunodeficiency virus, or HIV, attacks the body's immune system. By weakening the body's defences against disease, HIV makes the body vulnerable to a number of potentially life-threatening infections and cancers. HIV is infectious, which means it can be transmitted from one person to another.
If left untreated, HIV will almost always deplete the immune system. This leaves the body vulnerable to one or more life-threatening diseases that normally do not affect healthy people.
This stage of HIV infection is called AIDS, or acquired immunodeficiency syndrome. The more the immune system has been damaged, the greater the risk of death from opportunistic infections.
The main objective of second generation HIV surveillance is to monitor HIV-AIDS and high-risk behaviour trends over time in order to provide essential data needed for the development of interventions and the evaluation of their impact.
OVERVIEW
- The first cases of human immunodeficiency virus (HIV) infection were reported in the Western Pacific Region in the mid-1980s. In 2004, it is estimated that at least 1.5 million people were living with HIV/AIDS in the Region. The majority of infected individuals are men (ratio of reported cases of women to men was 1:4.7 in 2001).
- Like Cambodia, Papua New Guinea is now facing a generalized epidemic. However, in Cambodia, the situation has improved -- a decrease in HIV prevalence in some vulnerable groups, such as sex workers, and a dramatic decrease of the number of yearly new infections. This is related to well-targeted prevention efforts. But at the same time, the means of transmission are changing; nearly half of all new HIV infections are among wives of infected men and one third are among children of infected mothers.
- In some other countries -- China, Malaysia and Viet Nam -- there are focal areas of high HIV transmission among vulnerable groups, particularly sex workers and their clients, injecting drug users and men having sex with men. In some areas of these countries with concentrated epidemics, the HIV epidemic is now spreading from high- risk groups to the general population.
- There is a danger that increasing levels of HIV infection among highly vulnerable populations may lead to the epidemic spreading to the wider community. Efforts to reach those most at risk of infection with large-scale interventions of proven effectiveness must continue and indeed be increased.
- As the epidemic grows, the number of AIDS cases increases. That implies a growing need for more efforts to be directed at AIDS care. It is estimated that about 70 000 people died of AIDS in 2003 and about 120 000 will die in 2005.
- Tracking the HIV epidemic helps to provide accurate picture of the epidemic, enables situation analysis to be carried out, and supports the implementation of interventions and evaluations. The Western Pacific Regional Office continues to promote second-generation HIV surveillance in the Region, and assists Member States in improved surveillance system, data collection, data analysis and review, as well as HIV related strategic information. In collaboration with UNAIDS and other partners, WHO is supporting HIV estimate process using standardized methods for a number of countries.
- By the end of June 2004, the Global Fund to Fight AIDS, Tuberculosis and Malaria, with its four rounds, approved a total of 13 HIV/AIDS proposals in the Region for a total amount of US$ 297 million. The excellent and close collaboration among countries, UNAIDS and WHO country and regional offices has contributed greatly to the high success rate of proposals to the Global Fund from this Region.