1. HIV & AIDS Pages 919-921; IB Topic 6.3

2. Turn and Talk What do you know or think of HIV & AIDS?

3. Talking Point http://www.nytimes.com/1987/09/01/o pinion/on-my-mind-our-house-in- arcadia.html

4. Introduction Human immunodeficiency virus (HIV) is the virus that eventually results in a set of symptoms collectively called acquired immune deficiency syndrome (AIDS)

5. Some background information 1981 U.S. healthcare workers noticed an increase in the number of cases of Kaposi’s sarcoma & pneumonia These observations led to what came to be known as acquired immunodeficiency syndrome (AIDS) 1983 The retrovirus human immunodeficiency virus (HIV) was discovered as the cause of AIDS

6. Where did HIV come from? A lot of different theories & conspiracy theories Molecular studies of HIV reveal the virus probably evolved from another HIV-like virus in chimpanzees in central Africa Believed to have appeared in humans between 1915-1940 Unrecognized

7. HIV There are two strains of HIV HIV-1 & HIV-2 HIV-1 is more widely distributed and virulent

9. How HIV damages the immune system All viruses must find a type of cell in the body that matches their own proteins This is why only certain body cells are damaged by certain viruses reflected in the symptoms associated with the particular infection Ex: a cold virus locates the proteins on the mucus membrane cells in your nasal region and danger those cells Results in swelling of the area and excessive mucus production

10. How HIV damages the immune system The same is true for HIV Only certain cells in the body have the protein in their membranes that HIV recognizes One of those cells … Is the helper T cell More specifically, CD4 receptors This is the cell HIV infects

11. HIV is a retrovirus HIV-RNA is reverse transcribed The product DNA is integrated into the host genome Directs the production of new virus particles Because the virus exists within the infected cell, the immune system fails to eradicate it

12. How this affects the immune system Helper T cells communicate which cells need to undergo the cloning process and begin antibody production If these cells die, the communication no longer exists Antibodies do not get produced At this stage, the individual can no longer fight off pathogens Secondary infections ultimately take the life of someone with AIDS

13. Other facts/challenges Accumulation of mutations from viral replication Difficult to develop a vaccine or cure HIV has a latency period Infection occurs, but cells remain alive Usually years after HIV infection before the symptoms of AIDS develops

14. The stages of HIV infection Figure 43.20 Immune response diminishes viral load; however, HIV continues to replicate Viral load rises T cells decrease Extensive loss of cell-mediated immunity

16. HIV tests Detection of HIV-1 antibodies Appear in the blood about 1-12 months after infection Called an ELISA Enzyme linked immunosorbent assay

17. Symptoms/Stages Initial infection (primary or acute) Feels like the flu Fever, headache, nausea Chronic infection Swollen lymph nodes

18. Symptoms of AIDS Weight loss Reoccurring respiratory tract infection Skin rashes/ulcers Opportunistic infections Pneumonia Cancers Herpes

19. No cure HIV cannot be cured & progression to AIDS cannot be prevented Drugs can slow the process Slow viral replication Expensive Not available to all 30-40 million people have HIV/AIDS 70% in sub-Saharan Africa

20. Transmission Bodily fluids Semen, pre-ejaculate, vaginal fluid, breast milk, blood Unprotected sex Vaginal, oral, anal Drug use Sharing needles Breast feeding Birth (parinatal transmission) Blood transfusions Not the case anymore – all donated blood is screened for HIV However, this was not the case until the mid-1990s Numerous cases of people contracting HIV from blood transfusion

21. Misconceptions/Stereotypes Originally labeled as a disease affecting homosexuals & drug abusers Back to the group of people in 1980 This initially led to some reluctance in allocated $ for HIV research AIDS is rapidly spreading among heterosexuals Biggest spike in African American females

22. Turn and talk Discuss the social, emotional, political and financial issues related to AIDS

23. Issues related to AIDS Education Access to health care Stereotypes Employment Finances