AIDS is an acronym for the acquired immune deficiency syndrome, which is an infection caused by a retrovirus known as the human immunodeficiency virus (HIV) which destroys the body’s defence mechanisms and allows severe infections and cancers to develop. In the very early days of research into the virus responsible for AIDS, it was described as human T-cell lymphocytotrophic virus 3 (HTLV3).
How did AIDS form?
The story begins in central Africa, where it is now believed a form of AIDS has existed in apes for thousands of years. These animals come into close contact with humans in this area, and are butchered and eaten by the local population. At some stage in the early part of the 1900s, the virus spread from apes to humans. In apes, due to natural selection over many generations, the virus causes few or no symptoms, and is harmless.
The AIDS virus has been isolated from old stored tissue samples dated in the 1950’s, found in Kinshasa hospital, Zaire. From Africa, AIDS spread to Haiti in the Caribbean. Haiti was ruled by a vicious dictator (Papa Doc Duvalier), and many Haitian Negroes fled to Africa to avoid persecution.
Once “Papa Doc” and his son “Baby Doc” were removed from power, these exiles returned, bringing AIDS with them. The virus mutated in humans and became more virulent, causing a faster and more severe onset of symptoms. Viruses mutate routinely (eg. different strains of influenza virus every year).
American homosexuals frequented Haiti because it was very poor, and sexual favours could be bought cheaply. A man known as “patient zero” by the US Centre for Disease Control has been identified as the person who introduced AIDS to the United States. He was an airline steward who infected more than 50 other men before dying of AIDS in 1984. It has spread around the world from the USA since then. The first cases were diagnosed in California in 1981, although cases occurred in Sweden in 1978 in the family of a sailor who had visited Haiti, but the disease was not identified as AIDS until years later. There may also have been some movement of the disease directly through Africa to Algeria and France.
Fortunately for most of us, it is a relatively hard disease to catch. AIDS is spread by the transfer of blood and semen from one person to another. It was initially only a disease of homosexuals and drug addicts, but although these remain the most affected groups in developed countries, it is promiscuous heterosexual contact that is the most common method of transmission in poorer countries. In the early days of the disease, some unfortunate recipients of blood transfusions and other blood derived medications were inadvertently given the AIDS virus. Tests are now available to allow blood banks to screen for AIDS.
Categories of AIDS
The disease has been classified into several categories. A patient can progress to a more severe category but cannot revert to less severe one. The categories are: –
- HIV category 1 – a glandular fever-like disease that lasts a few days to weeks with inflamed lymph nodes, fever, rash and tiredness.
- HIV category 2 – no symptoms.
- HIV category 3 – persistent generalised enlargement of lymph nodes.
- HIV category 4 (AIDS) – varied symptoms and signs depending on the areas of the body affected. May include fever, weight loss, diarrhoea, nerve and brain disorders, severe infections, lymph node cancer, sarcomas, and other cancers. Patients are very susceptible to any type of infection or cancer from the common cold to pneumonia, septicaemia and multiple rare cancers (eg. Kaposi sarcoma) because the body’s immune system is destroyed by the virus.
Blood tests are positive at all stages of HIV infection, but there may be a lag period of up to three months or more from when the disease is caught until it can be detected.