Discussion:
1. Explain the various modes of transmission for HIV. How does HIV convert into AIDS?
Please explain whether you agree with my classmate answer to the above question and why? (a mininum of 150 words)
Classmate's post
HIV is a retrovirus, a virus that uses RNA as its genetic material instead of the more usual DNA, that now infects over 33 million individuals and kilos almost 2 million a year. The target of HIV is a specific type of white blood cell called the CD4-Tlymphocyte, or T4 cell.
T4 cells are just one of many components of the complicated immune machinery that is activated when the blood recognizes a foreign invader such as a bacterium or a virus. In a T4 cell that is infected with HIV, activation of the cell activates the virus also, which then produces thousands of copies of itself in a process that kills the T4 cell.
Thus, destruction of the T4 cell disrupts the entire immune system. The course of infection with HIV takes place over several years. After being exposed to HIV, a person may or may not notice mild, flu-like symptoms for a few weeks, during which time the virus is present in the blood and body fluids and may be easily transmitted to others by sex or other risky behaviors. The infection then enters a latent period, which the viruses mostly hidden in the DNA of the T4 cells, although a constant battle is taking place between the virus and the immune system.
Eventually however, after several years, the immune system begins to lose the struggle, and so many of the T4 cells begin to die that they cannot be replaced rapidly enough. When the number of T4 cells drops below 200 per cubic millimeter of blood, about 20 percent of the normal level, symptoms are likely to begin appearing, and the person is vulnerable to opportunistic infections and certain tumors.
At the same time, the number of circulating viruses increases, and the person again becomes more capable of transmitting the infection to others. At this stage, the person meets the criteria for AIDS, which is defined by the T4 cell count and/or the presence of opportunistic infections.