2. National Reference Laboratory
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• HIV is the virus that causes AIDS.
• It attacks the immune system - the body's defense against disease.
• HIV is a virus that attacks the body and makes it weak. When the
body is weak, it is easier to get coughs, diarrhea, fever and other
health problems.
•HIV is found in blood, breast milk, semen and vaginal fluids.
HUMAN IMMUNODEFICIENCY VIRUS (HIV)
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AIDS has two faces..
HIV INFECTION – Successful entry
of Human Immunodeficiency Virus
inside the body; no signs or symptoms
AIDS –Acquired Immune Deficiency
Syndrome; terminal stage;
with signs and symptoms;
presence of opportunistic
infections
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• The immune system is the body's defense system
against diseases.
• White blood cells called lymphocytes play an
important role in helping the body's immune system.
CD4 cells are a special type of lymphocyte.
• In HIV infection, the virus attacks the immune
system. HIV destroys the special CD4 cells, and it is
the loss of CD4 cells that leads to the weakening of
the immune system.
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• CD 4 – A large glycoprotein that is found on the
surface especially of helper T cells, that is the
receptor for HIV, and that usually functions to
facilitate recognition of antigens by helper T cell.
• T Cell – Any of several lymphocytes (as a helper T
cell) that differentiate in the thymus, posses highly
specific cell-surface antigen receptors, and include
some that control the initiation or suppression of cell-
mediated and humoral immunity (as by the regulation
of T and B cell maturation and proliferation) and
others that lyse antigen-bearing cells– called also T
lymphocyte compared B cell.
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• Helper T cell – A T cell that participates in an
immune response by recognizing a foreign antigen
and secreting lymphocytes to activate T cell and B
cell proliferation and that usually carries CD4
molecular markers on its cell surface.
• B cell – any of the lymphocytes that have antigen-
binding antibody molecules on the surface, that
compress the antibody-secreting plasma cells when
mature, and that in mammals differentiate in the bone
marrow.
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IMMUNE SYSTEM
1) When viruses enter a healthy
body, they are detected and
identified by macrophage
cells. The macrophage cells
alert a T cell.
2) The cell is activated and
multiplies into several kinds
of T cells. Helper T cells
stimulate the B cells.
3) The B cells multiply and
produce antibodies that attack
and kill the invading viruses.
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ATTACK MECHANISM
1) When HIV attacks, it infects the T
Helper Cells first blocking their
ability to recognize foreign
substances then changing the T
cells into HIV factories.
2) Because the T cells no longer
perform their infection-fighting
role,invading viruses can roam
free. Meanwhile, the damaged T
Cells produce HIV, which invades
other T cells.
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Phases of Progression of HIV Infection into
AIDS
• 1. HIV Infection
The time when HIV is introduced into the body and
starts to multiply and spread.
• 2. Window Period
The time from HIV infection to the time when the
body begins to make detectable antibodies. It lasts
approximately 3 to 6 months after HIV infection.
During the window phase, HIV infected individuals
are infectious. If an individual takes an HIV test
during this time, it will come out negative although
he or she is HIV positive (called a false negative).
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• 3. Seroconversion
• The time when a person’s blood starts developing antibodies
to help fight HIV infection.
• Seroconversion occurs approximately 6 -12 weeks after HIV
infection (when the window period ends. Individual will now
test positive for HIV. 30 - 50% of people suffer from a flulike
illness during this time (fever, swollen lymph nodes, night
sweats, skin rash, headache or cough).
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• 4. Asymptomatic phase
• Asymptomatic HIV is the period during which a person will
test positive for HIV, but does not have any signs or symptoms
of the disease.
• PLWHA can remain asymptomatic for 10-15 years or more.
Generally no signs or symptoms, but may be accompanied by
swollen glands for a long time without any other symptoms of
disease
• It is during the asymptomatic phase that people are at greatest
risk of transmitting HIV. Because they may look and feel
healthy, they may not know that they are HIV positive and
may be passing on the virus.
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• 5. HIV-Related illness
• During an HIV-related illness, PLWHA begin to show signs
and symptoms of disease. This occurs after the asymptomatic
phase and can last from months to years, depending on
treatment of Opportunistic Infections and availability of
ARVs.
• HIV-related symptoms increase due to an increase in the
amount of HIV virus in the body and the destruction of CD4
cells and other important immune system functions. During
this period people will begin to develop increasing
opportunistic infections (weight loss, chronic diarrhea,
prolonged fever).
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• 6. AIDS Acquired Immune Deficiency Syndrome
(AIDS)
• AIDS is the life threatening or ‘terminal’ stage of
HIV infection. The immune system is severely
weakened in PLWA, and cannot cope with infection.
This creates a life threatening condition. Once a
person has AIDS, he or she can be expected to live
for one to two years if no treatment is available.
• HIV Wasting Syndrome – unexplained weight loss
greater than 10%, chronic diarrhea for longer than
one month and chronic fever for longer than one
month.
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• A CD4 count of less than 200 Life threatening
infections and cancers develop such as:
• Severe lung infection
• Severe infection of the eyes
• Fungal infections that cause thrush in the mouth, or
infections
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How is HIV Transmitted?
• Infected semen and vaginal fluid through
sex contacts whether vaginal, anal or oral.
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• Infected blood and blood products by:
Blood transfusion Organ transplant Sharing of contaminated
needles and syringes
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WHO ARE AT RISK?
Recipients of contaminated
blood and blood products
Multiple sexual partners
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PROCESS OF SCREENING
TEST
1. COUNSELLING
- PRE-TEST
- Basic knowledge,risk assessment,
Positive & negative result interpretation
- Secure consent(written & informed)
29. National Reference Laboratory
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2. Blood sample is taken
- coding - to ensure the
confidentiality on the subject’s
identity.
3.Post test counseling
4.If found twice positive for the screening test
*WESTERN BLOT (a test which
detects antibody to the major
proteins that make up the virus.
5.If the 1st screening result is negative,no further test
is done
30. National Reference Laboratory
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HIV TEST ALGORITHM
SCREENING
(Pre-test counseling)
ELISA or Particle Agglutination(PA)
REPORT RESULTS REPEAT
(Post test counseling)
(-) (+)
Report results Western Blot
(Post test counseling)
(-) (+)
Indeterminate
repeat after 3-6 months
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CONFIRMATORY
• Private and Government Laboratories
• STD AIDS COOPERATIVE CENTRAL
LABORATORY (SACCL)
• National Reference Laboratory for HIV/AIDS,
Hepatitis and Sexually Transmitted Diseases
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CANCER
Kaposi’s sarcoma
• cancer of the small blood vessels
• most common cancer in AIDS
patients
• patch stage (bruise);plaque
stage(less
• diffuse and slightly raised;
nodular;
• ulcerative
• pale pink, violet, dark brown –
painless and non-tender
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APPROACHES TO HIV/AIDS
MANAGEMENT
• COUNSELING
• PREVENTION OF TRANSMISSION
• SCREENING
• EDUCATION
• ANTIRETROVIRAL THERAPY
• SYMPTOMATIC MANAGEMENT
• ANTIMICROBIAL PROPHYLAXIS
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CONSIDERATIONS IN
ANTIRETROVIRAL THERAPY
• CLINICAL OBJECTIVES
Improve survival
Reduce impact of HIV disease
Improve quality of life
Increase in body weight
• SURROGATE END POINTS
Reduce viral load
Improve immune
function(CD4 cell count)
35. National Reference Laboratory
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PREVENTION
1. ABSTINENCE
2. BE FAITHFUL
3. CONDOM USE
4. AVOID DRUG MISUSE
5. ENCOURAGE VOLUNTARY BLOOD
DONATION
6. INFECTED FEMALES - PREGNANCY
ISSUES
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ADVOCACY
• MULTI-SECTORAL INVOLVEMENT
• WORLD AIDS DAY CAMPAIGN
• CANDLELIGHT MEMORIAL
CELEBRATION
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Current Situation
Increasing HIV Statistics
Increasing STI Statistics
Dwindling Resources
Rapid Turnover of Health
Personnel