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Understanding AIDS
Acquired Immune Deficiency Syndrome, or AIDS, was first reported in
mid-1981 in the United States; it is believed to have originated in
sub-Saharan Africa. The human immunodeficiency virus (HIV) that causes
AIDS was identified in 1983, and by 1985 tests to detect the virus were
available. The credit for discovering the AIDS virus is jointly shared by
Dr. Robert Gallo, a researcher at the National Cancer Institute, and Luc
Montagnier of the Pasteur Institute, France.
Destruction of Immune System
A fatal and incurable disease caused by HIV, AIDS attacks and destroys
the immune system, gradually leaving the individual defenseless against
illnesses that lead to death. These illnesses are referred to as
“opportunistic” infections or diseases: in AIDS patients the most common
are Pneumocystis carinii pneumonia (PCP), a parasitic infection of the
lungs, and a type of cancer known as Kaposi's sarcoma (KS). Other
opportunistic infections include unusually severe infections with yeast,
cytomegalovirus, herpes virus, and parasites such as Toxoplasma or
Cryptosporidia. Milder infections with these organisms do not suggest
immune deficiencies. Symptoms of full-blown AIDS include a persistent
cough, fever, and difficulty in breathing. Multiple purplish blotches and
bumps on the skin may indicate Kaposi's sarcoma. The virus can also cause
brain damage.
People infected with the virus can have a wide range of symptoms—from
none to mild to severe. At least a fourth to a half of those infected with
HIV will develop AIDS within four to ten years. Many experts think the
percentage will grow much higher.
Transmission
Although the first reported cases involved homosexual men in Los
Angeles who were infected through sexual contact, the principal mode of
transmission throughout the world is through the exchange of bodily fluids
during heterosexual intercourse. According to the World Health
Organization, extensive spread of HIV appears to have begun in the late
1970s and early 1980s. It spread in men and women with multiple sexual
partners in East and Central Africa and among homosexual and bisexual men
in certain urban areas of the Americas, Australasia, and Western
Europe.
In addition to sexual contact, AIDS has been spread by intravenous drug
users sharing infected hypodermic needles. The virus can also be passed on
through transfused blood or its components. It may also be transmitted
from infected mother to infant before, during, or shortly after birth.
Two major types of HIV have been recognized, HIV-l and HIV-2. HIV-l is
the dominant type worldwide. HIV-2 is found principally in West Africa,
but cases have been reported in East Africa, Europe, Asia, and Latin
America. There are at least ten different genetic subtypes of HIV-l, but
their biological and epidemiological significance is unclear at present.
Both HIV-l and HIV-2 are transmitted in the same ways.
Pandemic
With no cure at present, prudence could save thousands of people who
have yet to be exposed to the virus. Use of condoms lessens the
possibility of transmission, as does the elimination of sharing hypodermic
needles. The fate of many will depend less on science than on the ability
of large numbers of human beings to change their behavior in the face of
growing danger.
The introduction of highly active antiretroviral therapy in 1996 was a
turning point for those with access to sophisticated health-care systems.
Although they can't cure HIV/AIDS, antiretrovirals (ARVs) and their use in
combination, “cocktails,” have dramatically reduced mortality and
morbidity and prolonged and improved the lives of sufferers. However, 95%
of people with HIV/AIDS live in developing countries, where access to
these medicines remains unacceptably limited and the costs prohibitively
expensive. Progress has recently been made in India, however, as Indian
pharmaceutical companies are producing generic versions of ARVs and
selling them for less than $1 a day. Another obstacle is that not everyone
can tolerate the potent medications and their side effects. Doctors are
also reporting a significant increase of patients with drug-resistant HIV
strains. Some 100 separate drugs are either in use or being tested for use
against AIDS. In July 2006, the FDA approved the first single-pill,
once-a-day AIDS treatment, thereby allowing patients to manage their
disease without a complicated regimen of drugs that must be strictly
followed to be effective. The pill, called Atripla, is considered an
enormous breakthrough in AIDS treatment, and will help prevent the disease
from mutating into drug-resistant strains, which occurs when drugs are not
taken regularly.
On a global scale, men make up a slim majority of the 33.2 million
people living with HIV. However, in sub-Saharan Africa, which has about 22 million people living with HIV, women and girls
account for about 61% of adults living with the disease. In the Caribbean, the
figure hovers around 50%. The number of women living with HIV continues to
increase in Eastern Europe, Asia, and Latin America.
Information Please® Database, © 2007 Pearson Education,
Inc. All rights reserved.
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