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

HIV/AIDS discussion in micro

Where did HIV come from?




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



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


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

10.3 X10^9 virions are produced each day
Transmission

Heterosexuals on the rise






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

7 from same donor
transmission




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




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


95% in low and middle income countries
50% are 15-24 year olds

In US highest age group is 25-44 yoa

Fastest rate of increase is Black and South states
 In Maryland, % of AIDS cases by location: Suburban
Washington 32%, Suburban Baltimore 35%
Stats cont.


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

Syndrome after initial infection – 2-4
weeks after exposure, consists of fever,
adenopathy, pharyngitis, rash, m/c


Symptoms means more rapid progression
Seroconversion – 3 weeks after
transmission

>95% of patients seroconvert within 5.8 mo.
Occupational exposure of
2001

57 seroconversions




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


Goal: increase CD4, decrease viral load,
prevent secondary infection
Drug failures after 1 year: Baltimore 63%

Why – drug side –effects such as head ache, GI
intolerance, peripheral neuropathy,
lipodystrophy

Lipodystrophy – central fat accumulation, periphera
wasting, lipoma
lipoma
lipodystrophy
Long term drug side effects

Osteopenia, AVN, myopathy
(weakness), polymyositis, peripheral
neuropathy (burning, aching or numb)–
need vit D and Calcium