Purpose
The International AIDS Candlelight Memorial acts as a catalyst for
communities around the world to begin talking about HIV/AIDS in
their community. It is a unique event that promotes discussion,
education, awareness and action.
The International AIDS
Candlelight Memorial have four main objectives:
To honor the memory of those lost
to AIDS; To show support for those living with HIV and AIDS; To
raise community awareness and decrease stigma related to HIV/AIDS;
To mobilize community involvement in the fight against HIV/AIDS.
Turning Remembrance into
Action: 2004 Theme
On 16 May 2004, thousands of
individuals in more than 3000 communities in 85 countries will
participate in the world's largest and oldest annual grassroots
HIV/AIDS event.This year, there is a two-year theme that focuses on
remembering those who have been touched by HIV/AIDS and keeping
these memories alive through collective action.
The goal of this year’s theme is
to encourage communities to incorporate advocacy activities that
extend beyond the official candlelight event. It is an opportunity
to discuss the impact of HIV/AIDS within the community as well as
how your community will address issues such as prevention, care,
treatment, and education of the disease. This two year commitment
serves to strengthen ties within the community and empower
individuals to take action toward changing the face of HIV/AIDS
Number of people living with
HIV/AIDS in 2004
UNAIDS/WHO AIDS epidemic update of
2004 shows that the number of women living with HIV has risen in
each region of the world over the past two years, with the steepest
increases in East Asia, followed by Eastern Europe and Central
Asia. In East Asia, there was a 56% increase over the past two
years, followed by Eastern Europe and Central Asia with 48%.
During 2004 around five million
adults and children became infected with HIV (Human
Immunodeficiency Virus), the virus that causes AIDS. By the end of
the year, an estimated 39.4 million people worldwide were living
with HIV/AIDS. The year also saw more than three million deaths
from AIDS, despite the availability of HIV antiretroviral therapy
which reduced the number of deaths in high income countries.
Human Immunodeficiency Virus
Human immunodeficiency virus (HIV)
is the causative agent for AIDS. The most common type is known as
HIV-1 and is the infectious agent that has led to the worldwide
AIDS epidemic. There is also an HIV-2 that is much less common and
less virulent, but eventually produces clinical findings similar to
HIV-1. The HIV-1 type itself has a number of subtypes (A through H
and O) which have differing geographic distributions but all
produce AIDS similarly. HIV is a retrovirus that contains only RNA.
HIV is a sexually transmitted disease. Infection is aided by
Langerhans cells in mucosal epithelial surfaces which can become
infected. Infection is also aided by the presence of other sexually
transmitted diseases that can produce mucosal ulceration and
inflammation. The CD4+ T-lymphocytes have surface receptors to
which HIV can attach to promote entry into the cell. The infection
extends to lymphoid tissues which contain follicular dendritic
cells that can become infected and provide a reservoir for
continuing infection of CD4+ T-lymphocytes. HIV can also be spread
via blood or blood products, most commonly with shared contaminated
needles used by persons engaging in intravenous drug use. Mothers
who are HIV infected can pass the virus on to their fetuses in
utero or to infants via breast milk.When HIV infects a cell, it
must use its reverse transcriptase enzyme to transcribe its RNA to
host cell proviral DNA. It is this proviral DNA that directs the
cell to produce additional HIV virions which are released.The
genome of HIV contains only three major genes: env, gag, and pol.
These genes direct the formation of the basic components of HIV.
The env gene directs production of an envelope precursor protein
gp160 which undergoes proteolytic cleavage to the outer envelope
glycoprotein gp120, which is responsible for tropism to CD4+
receptors, and transmembrane glycoprotein gp41, which catalyzes
fusion of HIV to the target cell's membrane. The gag gene directs
formation of the proteins of the matrix p17, the "core"
capsid p24, and the nucleocapsid p7. The pol gene directs synthesis
of important enzymes including reverse transcriptase p51 and p66,
integrase p32, and protease p11. In addition to the CD4 receptor, a
coreceptor known as a chemokine is needed for HIV infection.
Chemokines are cell surface fusion-mediating molecules. Such
coreceptors include CXCR4 and CCR5. Their presence on cells can aid
binding of the HIV envelope glycoprotein gp120, promoting
infection. Initial binding of HIV to the CD4 receptor is mediated
by conformational changes in the gp120 subunit, but such
conformational changes are not sufficient of fusion. The chemokine
receptors produce a conformational change in the gp41 subunit which
allows fusion of HIV. The differences in chemokine coreceptors that
are present on a cell also explains how different strains of HIV
may infect cells selectively. There are strains of HIV known as
T-tropic strains which selectively interact with the CXCR4
chemokine coreceptor to infect lymphocytes. The M-tropic strains of
HIV interact with the CCR5 chemokine coreceptor to infect
macrophages. Dual tropic HIV stains have been identified. The
presence of a CCR5 mutation may explain the phenomenon of
resistance to HIV infection in some cases. Over time, mutations in
HIV may increase the ability of the virus to infect cells via these
routes. Infection with cytomegalovirus may serve to enhance HIV
infection via this mechanism, because CMV encodes a chemokine
receptor similar to human chemokine receptors.
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