Additional specifications and reference materials

Vaccines

From the creation of the world' first vaccine in the 1790's, that slowly eradicated the epidemic of small pox, scientists have continued to find cure for some of the world's most infectious diseases. Some of these are diseases that have plagued millions of people throughout history are yellow fever, measles, and polio.

Because vaccines have proven to be a very potent weapon against different diseases for almost two centuries now, vaccination is now being targeted as a probable solution to one of our time's most threatening and deadly virus- the Human Immunodeficiency Virus, or HIV. Aptly called as HIV, the said virus primarily attacks the human body's immune system, and if not detected early leads to the more serious case of AIDS, or Acquired Immunodeficiency Syndrome. The alarm over finding a cure for HIV or AIDS is understandably rampant since according to the United Nations (http://www3.niaid.nih.gov),an estimated 40 million people all over the world are affected with HIV; and the statistics all the more show its growing prevalence across ages and continents!Having said that the HIV attacks the body's Immune System, it is but logical to first review how the immune system works and how HIV ultimately attacks and destroys it.

It was in 1981, in the United States, when the first case of Acquired immunodeficiency syndrome or AIDS was reported. Through thorough research, it was observed that AIDS is actually is caused by HIV (human immunodeficiency virus) and is able to kill and/or damage the cells of the body's immune system. Specifically, the HIV gradually and painfully destroys the human body's ability to fight infections and certain cancers (NIAID, 2005). This is the very reason why many who have acquired HIV or AIDS result to an eventual death because of the lack of immune system that protects them from acquiring other forms of illnesses.

HIV can be transferred in a variety of ways. The most common way of getting infected by the disease is through having unprotected sex with an infected partner. The virus causing HIV can quickly enter the body through the lining of the vagina, vulva, penis, rectum, or mouth during sex. Other ways that can transfer HIV is through (NIAID, 2005):

Sharing drug needles or syringes that has contacted an HIV positive person - this may be a rare case of transferring the virus, but there have been significant number of cases wherein the use of used and contaminated syringes become the factor of infecting other people with HIV

Be transfused with a blood contaminated by the virus - Blood transfusion is necessary among patients who are having massive blood loss. Some would want to accept blood from nobody else, but the family, extended relatives or friends. However, there are some hospitals who will allow blood transfusion even without proper evaluation of the blood or the person who will donate the blood. In this instance, some people whoa re not aware that they have HIV transfused their own infected blood, deliberately or not.

Transmit HIV from mother to the baby during pregnancy. An estimated one-quarter to one-third of all the untreated pregnant women infected with HIV will pass the infection to their babies.

The Aaron Diamond AIDS Research Center (http://www.adarc.org/frame.asp?var=about_HIV") provides information on the five stages of HIV infection, namely: Entry, Reverse Transcription, Integration, Translation, and Exit. The first stage of the Entry of the HIV virion into the host cell known as the T-cell is triggered by the binding of membrane proteins of the virus into the receptors on the T-cell surface. The T-cell is a lymphocyte or white blood cell found in the bloodstream. Its main function is to protect and "eat away" or engulf foreign particles such as bacteria and viruses entering the body. In the event that a HIV virion entering a T-cell, the T-cell is eventually destroyed resulting to the weakening of the body's defenses. A shedding of the HIV' virion's capsid occurs in the second stage called the Reverse Transcription. In this stage, the viral RNA and its enzyme are exposed and then transcripted to becomea viral DNA. The third stage of Integration is characterized with the viral RNA's entry to the T-cell's nucleus to become integrated into the host DNA. Translation, which is the fourth stage is characterized by the viral RNA's creation of codes which are translated into proteins and enzymes into a polypeptide chain. Finally, the HIV virion exits the host T-cell by the formation of its outer layer called the capsid, insertion of its own viral membrane proteins into the host cell's plasma membrane, and budding from the surface of the host cell to infect other nearby T-cells.