Download HIV/AIDS discussion in micro - College of Southern Maryland

HIV/AIDS discussion in micro
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Where did HIV come from?
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Benign simian infection evolved into human
infection in the early 30s in southwest Africa
Considered a chronic disease now
Causes a depletion of CD4 cells (lymphocyte
receptor)
Inserts genetic material on host DNA creating
a permanent infection
Strains of HIV
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There are many strains of HIV – can be
infected by 1+ viruses and get superinfection
Can pass on drug resistant strains
AIDS defined: CD4 count <200/mm3,
Candidiasis (thrush), invasive cervical cancer,
HIV dementia or wasting, Kaposi’s sarcoma,
infections like mycobacterium
Kaposi’s
Kaposi’s
Always
Like
purple
the leg w/ assoc.
edema
CD4
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Type of WBC that carries CD4 surface marker
and helps the body fight infection. Also
known as Tcells or T helper cells. These cells
incorporate the HIV RNA
About 140 viral replication cycles occur each
year
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10.3 X10^9 virions are produced each day
Transmission
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Heterosexuals on the rise
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1985- 1.9%; 1997- 35%
Higher risk in uncircumcised due to warm moist
environ. Of foreskin
In Baltimore, 31% of IDU are HIV+ and 48% of all
new HIV cases were IDU in 2001
Blood transfusions – 1:450,000 false negative blood
tests
Perinatal transmission – 1.2% of all AIDS cases
Organ transplant – 10 since 1985 screening began
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7 from same donor
transmission
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Household contact: 8 total; 4 child to child, 3
patient to care giver, 1 parent to child
Deep kissing: 1 total; man with gingivitis
kissing a female
One case of two females sharing a sex toy
Health care worker to patient: 7 total; 6 from
Florida dentist, 1 orthopedic surgeon
Statistics - globally
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People living with HIV – 39.4 mill
New HIV infections in 2004 – 4.9mill
Deaths due to AIDS in 2004 – 3.1mill
About 14,000 new HIV infections/day in 2004
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95% in low and middle income countries
50% are 15-24 year olds
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In US highest age group is 25-44 yoa
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Fastest rate of increase is Black and South states
 In Maryland, % of AIDS cases by location: Suburban
Washington 32%, Suburban Baltimore 35%
Stats cont.
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Baltimore – 3rd highest AIDS rate in
2001 after New York and Miami with
50/100,000
Diagnosis to death with no treatment is
10-12 years
Acute HIV infection
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Syndrome after initial infection – 2-4
weeks after exposure, consists of fever,
adenopathy, pharyngitis, rash, m/c
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Symptoms means more rapid progression
Seroconversion – 3 weeks after
transmission
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>95% of patients seroconvert within 5.8 mo.
Occupational exposure of
2001
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57 seroconversions
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46 percutaneous exposures
23 nurses
Infectious body fluid: blood, semen,
vaginal secretions
Not infectious unless bloody: feces,
urine, snot, spit, sweat, tears, vomit
Drug therapy
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Goal: increase CD4, decrease viral load,
prevent secondary infection
Drug failures after 1 year: Baltimore 63%
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Why – drug side –effects such as head ache, GI
intolerance, peripheral neuropathy,
lipodystrophy
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Lipodystrophy – central fat accumulation, periphera
wasting, lipoma
lipoma
lipodystrophy
Long term drug side effects
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Osteopenia, AVN, myopathy
(weakness), polymyositis, peripheral
neuropathy (burning, aching or numb)–
need vit D and Calcium