HIV/AIDS discussion in micro

1. 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

2. 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

3. Kaposi’s

4. Kaposi’s • Always purple • Like the leg w/ assoc. edema

5. 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

6. 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

7. 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

8. 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%

9. 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

10. 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.

11. 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

12. 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

13. lipoma

14. lipodystrophy

15. Long term drug side effects • Osteopenia, AVN, myopathy (weakness), polymyositis, peripheral neuropathy (burning, aching or numb)– need vit D and Calcium