about HIV/AIDS
According to Greek mythology, when curious Pandora opened a forbidden box she set loose all the miseries and evils known to the world. One of them was undoubtedly the virus the very name of which is Latin for slime, poison and stench (Eigen, 1993 p. 42). Scientists do not precisely know the origin of viruses but some speculation suggests that viruses might have originated either as primitive molecules that invaded living cells or as viral genes which broke away from cells and became independent, parasitic-like agents. Viruses can infect most living things including plants; they lie dormant until they can find a living host to invade. In humans, viruses are known to cause a variety of illnesses, ranging from the common cold to smallpox, polio and HIV/AIDS. During the early research of viruses, scientists were "puzzled by the high mutation rates they observed: the magnitudes indicated that viruses must evolve more than a million times faster than cellular microorganisms" (Eigen, 1993 p. 42). Viral particles are so small that 100,000 gathered together are scarcely visible (and until the widespread use of electron microscopes beginning in the 1930s, viruses could not been "seen"). Viruses have a genetic program whose purpose is to multiply inside its host. "All viruses, including HIV, are primitive creatures: tiny bundles of genes wrapped in protein, quite unable to reproduce until they've infected their chosen host" (Caldwell, 1993, p. 62). HIV has morphological, biological, and molecular similarities to viruses affecting animals, but until now not known to affect humans. These viruses are "retroviruses" -- ones that are regressive -- they "go backward." A retrovirus changes the original molecular structure of its host cell... These cells become HIV cells forever (McKenzie, 1991, p. 19).
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