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HIV / AIDS - Introduction

The emergence and pandemic spread of the Acquired Immune Deficiency Syndrome (AIDS) constitute the greatest challenge to public health in modern times. The full consequence of this disease may not be evident for several years because of the silent spread and slow evolution of this infection.

AIDS came to light only in 1981 when it caused outbreaks in the USA but virus appears to have been seeded in the United States at least in the mid 1970s and few unrecognised cases of AIDS had occurred in New York in 1978.

The origin of the virus has been the subject of much controversy, reminiscent of the situation five hundred years ago when syphilis was first recognised. It has been suggested that the virus may have been originated in Africa, perhaps from a simian immune deficiency virus and spread to the USA, probably through Haiti. In 1970s,USA, virus spread widely among male homosexuals and drug addicts, then come out as outbreaks in 1981. The virus may have spread to Europeans from America, as well as directly from the former African colonies of European nations.

The first indication of this syndrome began in 1981, when reports came New York and California of a sudden increase in the incidence of two rare diseases, Kaposi’s sarcoma and pneumocystis carinii pneumonia in young adults. Those patients appeared to have lost their immunity owing them to vulnerable parasitic and bacterial infections. Because of this disease causing immunity lost, the name was given as ‘Acquired Immune Deficiency Syndrome’.

Isolation of the aetiological agent was first reported in 1983 by Luc Montagnier and colleagues from Pasture institute, Paris. They isolated a retrovirus from West African patients with persistent generalised lymphadenopathy. Therefore, the virus called Lymphadenopathy Associated Virus (LAV).

In 1984, Robert Gallo and colleagues from the National Institute of Health, USA reported isolation of a retrovirus from AIDS patients and called it Human T cell Lymphotropic Virus - III (HTLV - III).

Other similar isolates were reported from AIDS cases under different name such as AIDS-Related Virus (ARV).

To resolve this nomenclatural confusion, the International Committee on Virus Nomenclature in 1986 decided on the generic name ‘Human Immunodeficiency Virus (HIV)’ for these viruses.

The virus has spread virtually all over the world, though the prevalence rates in different countries vary widely. North America, Brazil, Western Europe, Australia, Central and West Africa have high prevalence, while Eastern Europe and Asia are only sparsely affected. Differences also exist, both in modes of infection and in clinical manifestations, between the affluent and developing countries.

The disease is being reported in men, women and children from all over the world. According to UNAIDS/WHO, there are 42 million HIV infections worldwide. Nine out of ten do not know that they are infected. Adults account for 38.6 million cases and 3.2 million children are already infected.

There are 16,000 new HIV infections, occurring per day, 90% of which are in the developing world. Every day, at least 7,000 young people, aged 10 to 24 are infected with HIV. This recognized as five young people in every minute.

Every year in Africa 1.7 million is infected.

Every year in Asia and Pacific 700,000 people, get the infection.

The continued increase in HIV infections particularly in South and Central Africa and in South and Southeast Asia is likely to accentuate the impact of HIV/AIDS on the developing world.

Although, HIV came later to Asia, it is spreading in South and Sout5h-east Asia at an alarming rate. By year 2000, WHO estimates that between 8 and 10 million men, women and children in Asia will have been infected with HIV.

In many countries, the virus has now begun to spread into the general population as well. HIV infection rates in pregnant women of 8% in Chiang Mai (Thailand), 4.2% in Mumbai (India) and 3-7% in parts of Myanmar bear testimony to the fact. The number of children being infected perinatally also continuously increasing. The future scenario also projects that by the year 2000, more Asians than Africans are likely to be infected every year. The projections underline the need for dealing with HIV/AIDS on a war footing.

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