1. Chapter 17: HIV/AIDS

2. HIV/AIDS -HIV: Human Immunodeficiency Virus -AIDS: Acquired Immunodeficiency Syndrome -AIDS represents the end stage of infection by HIV

3. Some Facts -First discovered in 1981 -Originally called ‘The Gay Cancer’ -Within two decades 22 million people died -Worldwide about 40 million people are infected with HIV -Thought to have originated from chimpanzees

4. Transmission -Only transmitted through exchange of blood or certain bodily fluids -Unprotected sex -Semen and vaginal fluid -Blood-to-blood contact -Hypodermic needles -Blood transfusions -Mother-to-baby -At birth -Breast feeding

5. The Virus -Retrovirus: contain RNA, reverse transcriptase, and protein coat -The virus must invade a host cell in order to replicate RNA -Thousands of copies of RNA are copied and leave the cell -10 billion viral copies can be made in one day -HIV damages helper T cells -Destroyed faster than replaced

6. Signs and Symptoms -Initially experience flu-like illness -Fever, fatigue, rash, headache, joint pain, sore throat, swollen lymph nodes -3-4 weeks -Antibodies secreted -HIV screening tests for antibodies -2-10 years -Progression to AIDS (helper T cells < 200/microliter of blood) -Persistent fatigue, weight loss, skin rashes, diarrhea, mouth and gum lesions -Susceptible to opportunistic infections

7. Treatment -There is no cure -Life-extending medications 1)Reverse transcriptase inhibitor -Interferes with viral RNA -> DNA process -ZDV, ddl, and d4T; Trizivir includes all three 2)Protease inhibitors - Interferes with assembly of the outer coat of the virus

8. Treatment -HAART: highly active antiretroviral therapy -Two reverse transcriptase inhibitors and one protease inhibitor -Delays the progression of virus returns individual to health -Very expensive ($10,000/year) and many bad side effects -Virus is still present in the lymphatic tissues and can be transmitted