Jamaican Researcher

Basic Facts about HIV/AIDS and the Human Body

Extract: The AIDS Booklet by Frank D. Cox (1999)

Q. What is AIDS?

A. Acquired (conditions are not inherited, but are acquired from environmental factors, such as virus infections) Immunodeficiency (the viruses gradually cause deficient immunity, which reflects poor nutrition and low resistance to infections and cancers) Syndrome (viruses cause several kinds of diseases, each with characteristic signs and symptoms).

AIDS is caused by a retrovirus that infects lymph glands and destroys lymphocytes through gene alteration, spreading the disease between individuals mostly through semen, blood, uterine secretions, breast milk, and placenta.

Q. What is HIV?

A. Human Immunodeficiency Virus is a retrovirus, which lacks DNA, therefore, depend on the DNA of other bodily cells like lymphocytes to reproduce. HIV is a highly variable virus which mutates very readily. This means there are many different strains of HIV, even within the body of a single infected person.

There are at least two types of viruses that can cause AIDS, AIDS related conditions, and cancers in human beings. Visit this link for details of HIV Groups and subtypes and see the summary of the two types below:

1. HIV-1 is the most common cause of AIDS worldwide, except in West Africa, where HIV-2 is relatively common. Scientists can identify up to nine major genetic subtypes of HIV-1
2. HIV-2- appears to be less virulent than HIV-1

Q. What is a virus?

A. A virus is a tiny poisonous particle that can cause disease and is too small to see with an ordinary microscope. Viruses depend on the living host cells like the lymph cells to grow and survive.

Viruses can be divided into DNA and RNA viruses. DNA viruses contain genes that direct virus growth. RNA viruses lack DNA and depend on the genes inside of other cells for growth and reproduction of the virus. HIV 1 is a n RNA virus, also called a retrovirus, because it randomly  reverses, transcribes, and inserts RNA into the DNA of the host cells, which in turn function abnormally or are killed.

Q. What are the stages of progression from HIV to AIDS?

A. There are four distinct stages in the development of HIV to AIDS. Visit this link for details of the Stages of Progression from HIV to AIDS or read the summary below:

1. Prodrome- the time during which aches, fever, and headache are the most common symptoms.
2. Latency- the time when overt symptoms are absent, the infection persists in the lymph glands and spreads by way of lymphocytes migrating from these lands
3. Generalized lymph gland enlargement and or autoimmune diseases, such as kidney or bone marrow failure occur
4. AIDS- the body will experience wasting, poor resistance to all kinds of infections; various forms of cancer and lymph gland destruction occur

Q. What is the function of lymphocytes?

A. Lymphocytes are white blood cells. They feed other cells, control cell growth, and guard against infection. They are the most common type of cell in our biological defense system- the immune system. They help prevent cancers by controlling cell growth and they help to protect against infections by producing antibodies (proteins that fight infections).

Q. How does HIV affect the immune system?

A. Each day you come in contact  with many infectious diseases, but your immune system protects you from getting sick. When you do get an infection the immune system manufactures antibodies that help fight the infection. When you get well, your body usually becomes immune to that particular infection. This is called acquired immunity, which means you will not get the disease again.

As the HIV infected lymphocyte produces antibodies, HIV is also reproducing. People do not develop effective acquired immunity to HIV because it grows in the very cells that produce antibodies. The destroyed or damaged lymphocytes in a HIV positive individual impairs the immune system from responding properly, making you much more susceptible to some of the many infections and diseases that exist within the environment, for example Tuberculosis.

Without a healthy immune system you would be sick all of the time. You would also be likely to develop malignant  (cancerous) growth of cells within your body. Thus a damaged immune system  fails to battle cancers that frequently  invade people with AIDS. As HIV progresses to AIDS in a human body, people ususally contract infections that are normally prevented by healthy antibody-producing and migrating white blood cells. Such infections are called opportunistic infections because they take advantage of the damaged immune system.