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Acquired Immune Deficiency Syndrome (AIDS) was first recognized in the United States in 1981 although the disease had already emerged in Sub-Saharan Africa. Twenty years later AIDS has become one of the most serious pandemics of all time. By the end of 2000, an estimated 36.1 million people around the world are living with HIV/AIDS; almost half of them are women. Through the end of 2000, cumulative AIDS-associated deaths around the world were estimated to be 21.8 million. The majority of those infected and dying from HIV disease are young adults, struck down in the prime of their lives when they ought to be at their healthiest and most productive.
The AIDS pandemic is really a complex picture of multiple epidemics with different patterns of transmission and different HIV subtypes predominating in various parts of the globe. We have allowed the AIDS pandemic to become a "them and us" situation. For example, of the 36.1 million people living with HIV/AIDS, 25.3 million (70%!) live in Sub-Saharan Africa. Of the 3 million deaths AIDS-related deaths reported in year 2000, 2.4 million were in Sub-Saharan Africa. Of the 5.3 milion adults newly-infected in year 2000, 3.8 million of these occured in Sub-Saharan Africa. For the majority of these individuals, expensive combinations of antiviral drugs are not an option and so far the main line of attack against AIDS has to remain that of PREVENTION!
The "them and us" scenario is
occuring in the United States. While AIDS is currently the fifth
leading cause of death among 25-44 year olds, it is the LEADING cause of
death for African-American
men and second leading cause of death fro African-American women.
In 1981 the CDC published the first case reports of Pneumocystis pneumonia in 5 previously healthy young gay men from Los Angeles. These were to become the first descriptions of what would later become to be known as AIDS.
By the end of 1981 there were close to 300 reported cases of a syndrome, primarily involving young gay men, which was causing people to become sick with opportunistic infections and cancers that either were relatively rare or that healthy people could normally control.
In the United States AIDS was
mistakenly called Gay-related immunodeficiency disorder (GRID). A
largely heterosexual epidemic in Africa was initially discounted as having
any connections to the disease in the U.S. By 1982/1983 AIDS cases
were reported in many different populations. The only common denominator
between them was HIV infection.
1. SEXUAL: through contact with HIV-infected semen and vaginal secretions ( the majority of HIV infections worldwide are acquired by heterosexual sex)
2. Direct exposure to HIV-infected
blood
or blood products and needles.
Tragically, it was known that
HIV was in US blood products and in the blood supply as far back as 1982.
The blood supply was not screened for the virus until 1985. Meanwhile many
thousands of hemophiliacs were infected with HIV and many since
have died of AIDS.
3. Vertical Transmission
from mother to child. The majority of infections
are believed to occur at time of delivery from exposure to infectious bodily
fluids. The virus can also be transmitted in breast milk and this route
is thought to be much more common in developing nations.
Scientists credited with the Isolation of HIV-1
The history surrounding the race to identify HIV is full of controversy. An interesting account can be found in the book "And the Band Played On" by Randy Shilts.
The AIDS virus was first isolated and described from a young gay man with swollen lymph nodes by a group of scientists headed by Dr Luc Montagnier at the Pasteur Institute in France in 1983. At the time Montagnier called the virus "lymphadenopathy virus" (LAV) referring to the swollen state of the lymph node. Shortly after, an American research group headed by Dr. Robert Gallo of the National Cancer Institute reported that they had also isolated the AIDS-causing virus which they called HTLV-III.
To cut a LONG story short it turned out that the viruses under study were essentially one and the same which lead to great controversy. Nevertheless, an agreement was reached by the French and Americans to share credit for the discovery of the AIDS virus. Both Montagnier and Gallo share the Nobel Prize.
The virus was subsequently renamed HIV:
AIDS stands for
HIV-2 in West African prostitutes and Simian Immune Deficiency Viruses (SIVs) from monkeys.
Why do we need an AIDS definition?
Between 1983
and 1985 AIDS became reportable to the CDC
in every state. New AIDS-defining illnesses were added to the definition
as well as a description of a mid-AIDS classification called "AIDS-Related
Complex." Individuals with ARC generally did
not know their HIV antibody status. ARC included symptoms such as
fatigue, night sweats and swollen lymph nodes and generally preceeded the
development of opportunistic infections.
By
1987 antibody tests became widely available
and the ARC classification was no longer necessary. Until 1992 the Social
Security Administration used the 1987 definition to determine disability
benefits. Due to the wording of the definition an estimated 65% of women
with HIV were excluded from receiving benefits.
In 1993 the CDC revised its case definition of AIDS. This revision included the sickest individuals with low CD4+ T cell counts and infections that were specific to women. It is this definition that is currently used:
"AIDS in an adult or adolescent 13 years or older is the presence of one of 26 conditions indicative of severe immunosuppression associated with HIV infection." An AIDS diagnosis is also given to HIV+ individuals when their CD4+ T cell count falls below 200 cells/cubic millimeter of blood.
The pediatric (<13) case definition is similar to that for adults except for the addition of certain opportunistic infections commonly seen in HIV+ children.
How is AIDS defined in developing
countries?
In many developing countries,
HIV antibody testing and facilities are not widely available. In these
situations a broader definition of AIDS is used according to guidelines
set by the World Health Organization. AIDS is considered in persons
with clnical symptoms of immune deficiency in the absence of any underlying
cause ( in other words, this looks like our early 1982 definition, when
testing was not available).
How have anti-viral drugs changed the face of the AIDS Epidemic?
1987: AZT
was approved as the first anti-HIV drug. Sadly, it was not unitl
the same year that President Reagan publicly acknowledged AIDS was a problem.
By then, we were 6 years into the epidemic and 50,000 Americans had already
died from AIDS.
There was an initital honeymoon
period with AZT as it slowed down viral replication and disease progression.
However, it soon became apparent that any monotherapy
used against HIV would be short-lives as the
virus could become drug-resistant in a matter of months to any one drug.
Following the development of AZT, other drugs in the same class of nucleoside
analogs were developed.
1994. A landmark clinical trial 076 was conducted in the U.S. which showed for the first time that a 2/3 reduction of HIV transmission from mother-to-child could be achieved by the use of AZT in late pregnancy. Drug regimens have since been improved to further reduce the risk of transmission.
1996 saw the introduction of a new class of powerful anti-AIDS drugs called protease inhibitors. The availability of potent combinations of antiviral drugs has dramatically improved the prognosis for HIV+ persons. For persons receiving drug therapy whose viral loads are driven to low or undetectable levels it has been repeatedly demonstrated that they are much less likely to develop opportunistic infections or die from AIDS.
BUT! Over 95% of the worlds HIV+ people live in developing countries with lack of access to affordable medication. Affordability is only part of the issue here, however. President Mbeki of South Africa continues to buy into the myth that HIV does not cause AIDS and that AIDS drugs are toxic. As a result, he continues to deny his people access to antiviral therapies.