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

Always purple Like 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 %; % 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 % in low and middle income countries 50% are year olds In US highest age group is 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 – 3 rd highest AIDS rate in 2001 after New York and Miami with 50/100,000 Diagnosis to death with no treatment is 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 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