 AIDS is the most severe acceleration of infection with HIV. HIV is a retrovirus that primarily infects vital organs of the human immune system such as CD4+ T cells (a subset of T cells), macrophages and dendritic cells. It directly and indirectly destroys CD4+ T cells.
Once HIV has killed so many CD4+ T cells that there are fewer than 200 of these cells per microliter (µL) of blood, cellular immunity is lost. Acute HIV infection progresses over time to clinical latent HIV infection and then to early symptomatic HIV infection and later to AIDS, which is identified either on the basis of the amount of CD4+ T cells remaining in the blood, and/or the presence of certain infections, as noted above.
In the absence of antiretroviral therapy, the median time of progression from HIV infection to AIDS is nine to ten years, and the median survival time after developing AIDS is only 9.2 months. However, the rate of clinical disease progression varies widely between individuals, from two weeks up to 20 years.
Many factors affect the rate of progression. These include factors that influence the body's ability to defend against HIV such as the infected person's general immune function. Older people have weaker immune systems, and therefore have a greater risk of rapid disease progression than younger people.
Poor access to health care and the existence of coexisting infections such as tuberculosis also may predispose people to faster disease progression. The infected person's genetic inheritance plays an important role and some people are resistant to certain strains of HIV. An example of this is people with the homozygous CCR5-Δ32 variation are resistant to infection with certain strains of HIV. HIV is genetically variable and exists as different strains, which cause different rates of clinical disease progression
Is HIV and AIDS the Same Thing?
HIV is the virus which damages the body's immune system. A damaged immune system leaves our body at risk for those illnesses and infections said to be AIDS defining. Acquiring one of these infections means a person is diagnosed with AIDS. A person can be infected for years without having AIDS. Having HIV infection does not mean you have AIDS. Simply put, HIV and AIDS are not the same thing.
What is HIV?
H = Human
I = Immuno-deficiency
V = Virus
HIV is the virus that causes AIDS. A virus is nothing more than a particle of biological material that can replicate itself, but for this to happen the virus needs the assistance of living cells. Some viruses prefer plant cells others prefer animal cells. Many viruses are restricted to a specific type of cell in the human body, and the HI virus interacts with specific cells in the body’s immune system. The immune system is a collection of tissues and cells that patrol the body for invading agents. HIV infects certain cells of the immune system and systematically depletes the body’s defences. In this way the immune system is rendered deficient and the person becomes sick.
To answer the question what is HIV AIDS, we have to start early in the epidemic. In 1985, scientists discovered the human immunodeficiency virus (HIV) and with it the question what is aids was answered. HIV is a virus that is transmitted from person to person through the exchange of body fluids such as blood, semen, breast milk and vaginal secretions.Within these bodily fluids, HIV is present as both free virus particles and virus within infected immune cells. The four major routes of transmission are unsafe sex, contaminated needles, breast milk, and transmission from an infected mother to her baby at birth (vertical transmission). Screening of blood products for HIV has largely eliminated transmission through blood transfusions or infected blood products in the developed world. Sexual contact is the most common way to spread HIV AIDS. As HIV AIDS reproduces, it damages the body's immune system and the body becomes susceptible to illness and infection. There is no known cure for HIV infection.
What is AIDS?
A = Acquired
I = Immune
D = Deficiency
S = Syndrome
If a person is infected with HIV he/she is said to be HIV positive. Eventually the virus is able to destroy the immune cells more quickly than they can be replaced, and the infected person begins to fall prey to opportunistic infections, i.e. tuberculosis or pneumonia, since the body’s natural defences have been severely weakened. The infected person is now said to have AIDS. AIDS is not necessarily a death sentence, but without treatment, a person in the developing world is usually expected to live for six to eight years from first being infected to developing full-blown AIDS.
Acquired immune deficiency syndrome, or AIDS, is a condition that describes an advanced state of HIV infection. With AIDS, the virus has progressed, causing significant loss of white blood cells (CD4 cells) or any of the cancers or infections that result from immune system damage. Those illnesses and infections are said to be "AIDS-defining" because they mark the onset of AIDS. Like HIV, there is no known cure for AIDS.
Resources:
aids.about.com
csa.za.org
en.wikipedia.org |
