GLOBAL PREVALENCE OF HIV

An estimated 33 million people are HIV positive worldwide. HIV-1, a retro virus is responsible for most cases world wide. HIV-2, a related virus produces a similar illness with a longer latent period. More than 3 million have acquired immune deficiency syndrome (AIDS). HIV infection is more prevalent among women and children in sub Saharan Africa. In previously healthy homosexual men cases of rare neoplasm, Kaposi’s sarcoma, and pneumocystis carinii pneumonia were reported in the USA during 1981. This epidemic was eventually termed as the acquired immunodeficiency syndrome (AIDS). The association between HIV virus infection and the development of AIDS was established in 1984. The global AIDS pandemic has stimulated unprecedented research on the pathogenesis, management and control of the disease that has expanded.

The world health organization estimates that number of people living with HIV in year 2007 was 33 million. Around 90% are in developing countries unable to afford the expensive medical care required to control the disease progression. WHO reported 2.7 million new HIV infections and 2.0 million deaths due to AIDS in 2007. Sub-Saharan Africa is the most-affected region in the world as measured by HIV/AIDS prevalence rates. An estimated 22 million adults and children are living with HIV in Sub Saharan African, 4.2 million in South and south east Asia, eastern Europe and central Asia 1.5 million, east Asia 740000, Oceania 74000, middle east and north Africa 380000, western and central Europe 730000, Latin America 1.7 million, north America 1.2 million, Caribbean 230000 respectively. The prevalence of disease is more than 96% in low and middle income countries. WHO reports, Over 7400 new HIV infections a day in 2007. The disease has affected about 1000 children under 15 years of age and about 6300 adults aged 15 years and older.

Women comprise 50% of adults estimated to be living with HIV/AIDS worldwide. Young people under the age of 25 years are estimated to account for more than half of all new HIV infections worldwide. The early epidemics of HIV was facilitated by travel and migration and later by female sex workers and their clients, important risk factor for transmission being the intravenous drug use and use of HIV infected blood and blood products. HIV probably originated from rural areas where it had been endemic at low levels but then spread amongst sexually active population in cities, initially in the early 1980’s amongst homosexual men in the developed countries of Europe, North America, and Australia. This series of epidemic was followed by a wave with predominant heterosexual spread in sub Saharan Africa and South America and lately to south East Asia, where the epidemics have been late in developing but are accelerating at an alarming rate.

There is no single AIDS epidemic worldwide. Instead, many regions and countries are experiencing diverse epidemics. The characteristic of HIV disease in each region are determined by many different microbiological, cultural, social and behavioral aspects. As for example, HIV infection in Uganda, where heterosexual transmission is predominant and infection rate is higher in rural areas. HIV infection in many parts of U.S remains rare, being seen amongst homosexual men and intravenous drug users at a highest rate in major cities. The epidemics in Europe, North America, and Australia have been stabilized, although cases contracted heterosexually and through vertical transmission continue to rise. So, far the sub Saharan African has been the hardest hit by HIV epidemic and rapid spread continues in south East Asia. HIV Infection has a profound impact in the economic and demography of a country. The life expectancy of many children’s are affected as a consequences of increasing heterosexual transmission of HIV. The prevalence of HIV is common between age groups 15 to 50 years who are the economically productive age groups in most countries.