Presentation on theme: ". Students know why an individual with a compromised immune system (for example, a person with AIDS) may be unable to fight off and survive infections."— Presentation transcript:
. Students know why an individual with a compromised immune system (for example, a person with AIDS) may be unable to fight off and survive infections by microorganisms that are usually benign. Standard 10 e
What are Retroviruses Have RNA not DNA Infected cells, DNA copy of RNA to insert into the Host Cell’s DNA Lays dormant for long time HIV is a retrovirus Harder to stop because can undergo more mutations. 10
Basic facts about HIV/AIDS HIV is the virus that causes AIDS HIV/AIDS is treatable, but not curable Approximately 30,000 people in LA are living with HIV You can’t tell by looking if a person is living with HIV, the only way to know is by taking an HIV antibody test. 9
HIV attacks the body’s immune system The immune system recognizes and attacks pathogens and antigens HIV attacks and destroys T-cells HIV replicates itself and attacks more T- cells to weaken the immune system so that it no longer functions Compromised immune system – weakened 8
The 4 Fluids Blood Semen Breast Milk Vaginal Fluids These are the four fluids that transmit HIV. The key to protecting yourself from infection is to avoid these four bodily fluids. 7
Transmitting HIV HIV is transmitted when one or more of the four fluids is transferred from one person to another. The most common ways HIV is transmitted is by: Unprotected oral, anal, or vaginal sex Sharing needles Breastfeeding from infected mother to baby 6
What is HIV and AIDS all about? Caused by HIV (Human Immunodeficiency Virus) Compromises your immune system Kills white blood cells (Helpers T-Cells) and can lead to AIDS (Acquired Immune Deficiency Syndrome) HIV contains 2 copies of RNA that penetrate a cell and hide for long time periods. In the infected cell, RNA is used to synthesize viral DNA. 5
How do you ensure you will never catch HIV? Abstaining from sex means not participating in sex at all. Abstinence is the only way to ensure that you will never contract HIV. Condoms reduce the risk for HIV, but they do not eliminate the risks altogether. 4
How HIV causes AIDS HIV invades immune system cells especially helper T cells. These helper T cells have a vital role in the immune system. When a helper T cell is activated (by having an antigen presented to it, it begins to divide into memory T cells and effector T cells. 3
Memory T cells Memory T cells do not fight against the virus. Instead they are long-lived and can generate an immune response quickly if the same foreign protein is encountered again. 2
Why is HIV hard to treat? Viral disguise Virus mutates and changing the proteins on its outer surface These new surface proteins are not recognized by the immune system’s memory cells. Mutant virus particles with new surface proteins survive immune system attacks and begin a new round of infection 1
Why is HIV hard to treat? Viral disguise Each round of infection reduces numbers of helper T cells because they are infected and destroyed. Each lineage of T cells has a limited ability to replicate, after a finite number of rounds of replication the body’s supply of helper T cells becomes exhausted. The immune system eventually is overwhelmed and collapses. 0
White Board questions follow.
A HIV is a virus that affects the immune system; AIDS describes a deficient immune system. B HIV is a virus that affects the immune system; AIDS is a bacterium that affects the immune system. C HIV is a virus that affects the immune system; AIDS is a virus that affects the whole body. D HIV is a disease that can be cured; AIDS is a disease that has no known cure. What is the difference between HIV and AIDS?
A can better fight off disease causing agents B are not able to contract these diseases C have a compromised immune system D have been vaccinated against such diseases Tuberculosis, meningitis, and hepatitis C are all diseases that are more common in people with HIV or AIDS. This is most likely because healthy people without HIV or AIDS __________.
How does the HIV virus cripple the immune system? A. destroys T–cells B. increases T–cells C. destroys H–cells D. increases B–cells
When macrophages and helper T cells start producing particles of HIV, __________. A the person will be immune to AIDS B the virus is spreading C helper T cells are being destroyed D Both B and C
A person that cannot fight off and survive infections by microorganisms that are usually harmless is said to have which of the following? A a healthy immune system B an increase in the amount of antibodies in the body C an increase in the amount of macrophages in the body D a compromised immune system
A person with an immune system compromised by a virus is unable to fight off infections because __________. A cells are not able to stop multiplying B cells stop producing antigens C killer T–cells destroy healthy body cells D helper T–cells are being destroyed by the virus
Which of the following systems does HIV destroy? A circulatory B skeletal C nervous D immune