HIV progression and factors affecting the tracking

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I have explained in details about HIV or AIDS in general, the popular laboratory markers for disease progression and the co-factors which can affect the natural course of HIV infection. Please try to understand the concepts and write in your own words to complete your above questions after taking out the relevant ideas from the material below.

HIV is a progressive disease, which gradually leads to deterioration of the immune system. The incubation time varies from one individual to another ranging from less then year to as long as even 20 years. Incubation period for AIDS (Acquired Immunodeficiency Syndrome) disease is defined from the point of the initial exposure to the HIV virus to complete appearance of AIDS-like symptoms which is characterized by a complete damage to the immune system showing an extremely low lymphocyte count and development of a host of opportunistic infections.

Laboratory Markers of Disease Progression:
Decrease in CD4 T-Lymphocyte count and presence of HIV RNA in the peripheral blood are the two most convincing tests for the presence of the virus and helps doctors to take definitive decision to begin HIV treatment for a patient.
CD4 T cells or "Helper Cells" play an important role because they carry antigens or infectious agents to various other immune cells like to Neutrophils, Natural Killer cells, Macrophages and monocytes. HIV infects these CD4 T cells and destroys them during their multiplication and propagation process. Freshly replicated HIV seeks for fresh CD4 cells as a result the body is left in a weakened state against infection and is susceptible to diseases. CD4 cell count in the body decreases as a result of HIV infection thus this decrease is a characteristic of HIV infection and routinely used now a days in the laboratory to monitor the severity & progress of HIV infection. Healthy people have between 600-1200 cells/mm3 of CD4 T cells in blood whereas HIV patients with severe infection can have their CD4 count even below 200 cells/mm3 in their blood. When CD4 cells reach very low, patients are at a high risk to developing various infections or even cancers, these are called opportunistic infections. This is considered an advanced stage of HIV infection or popularly known as Acquired Immunodeficiency Syndrome (AIDS). The common opportunistic infections includes:
a) Pneumocystis jiroveci pneumonia in the lungs
b) Kaposi's Sarcoma (KS), a type of skin cancer
c) Cytomegalovirus (CMV) -a viral infection that usually affects the eyes
d) Candidiasis- a fungal infection that can cause oral thrush in the mouth or infections in the throat or vagina.
e) Other AIDS related opportunistic infections include bacterial and viral infections. Bacterial infections include recurrent bacterial pneumonia, tuberculosis or TB and Mycobacterium Avium Complex (MAC). The viral infections include Hepatitis C & Herpes Simplex Virus (oral & genital herpes).
f) People living with HIV or AIDS are at a greater risk of developing certain cancers than people with healthy immune system. For instance the most common cancers include, Colorectal Cancer, Non-Hodgkin's Lymphoma (NHL) and lung cancer.
g) People living with HIV or AIDS are at a greater risk in developing primary and secondary cardiovascular disease (CVD).

Non-modifiable risk factors are risk factors we cannot do anything about these and they include the following: age, gender, ethnic origin and socio-economic position. Modifiable risk factors are risk factor for which we can do something about and these include: smoking, hyperlipidemia, hypertension, diabetes, mental stress, stimulant drugs(legal/illegal) and occupational carcinogens.

AIDS related complications ultimately lead to death of patients suffering from such infections. Treatment of anti-retroviral therapy (ART) can slow down the replication and partially restore the levels of CD4 count and subsequently immune function. However HIV infection at later stages causes permanent immune damage and patients do not recover with ART. HIV infection leads to fibrosis or tissue remodeling that causes damage to lymphatic tissue and is unable to maintain a population of CD4 cells particularly in lymph nodes and gastrointestinal associated lymphatic tissue. HIV ...