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What is a pandemic? Why is AIDS considered a pandemic?
A pandemic is a disease spread all over the world so AIDS would be considered a pandemic since it spread to all parts of the world.
When was AIDS first recognized as a disease?
When was HIV first isolated?
Is HIV-1 or HIV-2 more virulent? Which is largely responsible for the pandemic?
HIV-1 is more virulent and is largely responsible for the pandemic.
How is HIV transmitted? Which body secretions can transmit HIV?
HIV is transmitted through bodily secretions; those bodily secretions that transmit HIV are blood, semen, vaginal secretions, and breast milk.
What is a retrovirus? What is reverse transcriptase?
A retrovirus stores genetic material in the form of RNA and have the enzyme reverse transcriptase which converts RNA back to DNA.
What is GP120? What is GP41?
GP120 and GP41 both are glycoproteins that fuse together on the HIV virus to form "flagpoles" that becomes like a "key" that fits into the T cell receptor ("lock").
What is CD4? What is a T cell? What is a CD4 T cell?
- CD4 is a receptor for HIV in humans.
- A T cell is a type of lymphocyte that is developed in the thymus.
- A CD4 T cell is a white blood cell that is an essential part of the human immune system; called helper cells because one of its main roles is to send signals to other types of immune cells.
On what other cells (besides some T cells) is CD4 found on?
- Dendritic Cells
Why can't HIV infect chimpanzees?
Chimp CD4 cells are slightly different than human CD4 cells.
Describe the life cycle of HIV in detail.
- The retrovirus first has to be transmitted into the victim's body through bodily secretions (blood, semen, vaginal secretion, or breast milk).
- Once in the body, the retrovirus then finds a host cell in the lymph nodes to attach itself to.
- Once attached the retrovirus injects its genetic material (RNA) into the cell.
- That RNA is converted to DNA by an enzyme called reverse transcriptase.
- Then the host cell will take that DNA, thinking it belongs to the cell, and use the process of DNA transcription to make mRNA.
- The mRNA then goes to the ribosomes where it is then synthesized to proteins.
- The host cell replicates the DNA.
- These all come together in a vesicle to assemble another duplicate virus.
- That new virus then buds off and is released off the host cell and goes out into the body to mature and do the same thing to another host cell.
List the 5 specific ways in which HIV infection can be harmful.
- Drop in T cell count (immune response-more T cells made).
- Slow decrease in T cells (no symptoms yet).
- Rapid decline in T cell.
- Symptoms prevalent so person becomes more sick.
- AIDS (eventually death)
What is the definition of AIDS?
Autoimmune Deficiency Syndrome (AIDS) is a disease caused by the Human Immunodeficiency Virus (HIV). One of the major thing AIDS leads to is low count of CD4 T cells which makes the person susceptible to opportunistic infections.
What are opportunistic infections?
Infections take advantage of weakened immune system and cause devastating illnesses.
Is there an immune response to HIV? If so, why isn't it protective?
There is an immune response where more T cells are made but that just makes the virus attach itself to them and produce more of the HIV virus causing a slow then rapid decrease in T cells that eventually leads to AIDS.
What is Candidiasis?
A yeast infection caused by the fungus Candida.
What is Kaposi's sarcoma?
Rare form of skin cancer that causes purple lesions.
Why is it so hard to make a vaccine for AIDS?
The provirus is in the human chromosome for life and comes through the genital or cardiovascular route unlike the respiratory or GI tract which vaccines work most effectively on.
In general, how is AIDS testing done (the names of the tests and the order they are done, not the actual steps)?
An Enzyme Linked Immunosorbent Assay (ELISA) is done first then a Western Blot to finalize the results of the ELISA.
What is a chromogenic substrate?
A color producing substance.