Why AIDS Is So Deadly
TO UNDERSTAND better how to protect ourselves from AIDS, we need to know why it is so deadly. What makes this virus more difficult to deal with than other viruses?
Viruses are the smallest of all disease-producing organisms, much smaller than bacteria. Influenza, polio, and the common cold are produced by different viruses. Once inside a host cell, a virus may kill the cell or merely “sleep” there until it becomes more active later. With the AIDS virus, it may take five or more years before symptoms develop.
Why So Deadly
What makes the AIDS virus so deadly is the fact that it attacks and disables key cells, including white blood cells that the body produces to help ward off disease. These white blood cells (called T-4 lymphocytes) are the body’s main defense against disease.
When these white cells are disabled by the AIDS virus, they cannot do their job. Thus, the body’s immune system is devastated. Infections that may not previously have been life-threatening now are. These include other viruses, parasites, bacteria, fungi, or various cancers.
Since the body is no longer able to fight these infections, they progress until the victim is dead. These infections are called opportunistic. They take advantage of the opportunity afforded to them by the body’s suppressed immune system. A person with AIDS may have several such infections at the same time.
Among the early symptoms of AIDS are: prolonged and unexplained fatigue; swollen glands that last for months; persistent fevers or night sweats; persistent diarrhea; unexplained weight loss; discolored lesions of the skin or mucous membranes that do not go away; a persistent, unexplained cough; a thick whitish coating on the tongue or in the throat; easy bruising or unexplained bleeding. These early symptoms are often referred to as “AIDS Related Complex,” or ARC.
When AIDS becomes full-blown, deadly diseases develop. Among the more common are lung infections caused by parasitic germs known as Pneumocystis carinii, and the skin cancer called Kaposi’s sarcoma, which also involves internal organs. In addition, the AIDS virus can affect the brain, causing paralysis, blindness, dementia, and eventual death. Dr. Richard T. Johnson, a Johns Hopkins professor of neurology, stated: “HIV [the AIDS virus] is in the brains of at least 1 million people in the U.S.”
Full-blown AIDS is accompanied by pain and uncontrollable weight loss, with the body getting weaker and weaker until death ensues. In Africa, says The Lancet, AIDS “has been associated with ‘slim disease,’ a term that describes the great loss of weight that accompanies diarrhoea.” From the onset of the disease to death may take a year or less, or it may take several years.
A Persistent Virus
There is another factor that contributes to making the AIDS virus more deadly than others. It has built-in mechanisms for survival not common to other viruses.
For example, in humans the influenza virus may last only a few days or weeks, and it stimulates antibodies that help to protect the victim from further infection by that particular virus. Once the epidemic runs its course, it disappears. The flu pandemic of 1918 lasted only about a year. The yellow fever virus depends on mosquitoes, which diminish in number with seasonal changes. Smallpox may also quickly run through a susceptible population and then disappear.
However, the AIDS virus is presumed to be persistent. It probably stays inside the human host for a lifetime and does not disappear on its own. The victim does not recover from the full-blown AIDS disease and so is unable to build the kind of immunity that would resist a recurrence.
Furthermore, the AIDS virus has shown significant variation in its genetic composition, making it more difficult to develop a vaccine. And viruses usually mutate, that is, change their character. For example, there are many different types of influenza and cold viruses. Already, a second type of AIDS virus has been identified in Africa and elsewhere. A different vaccine may be required for each type.
But why has AIDS spread so widely? What practices were involved that helped its insidious infiltration into the human family?
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FACTORS THAT PREPARE THE WAY FOR AIDS
According to the British medical journal The Lancet, each year more than 300 million additional people throughout the world become infected with sexually transmitted diseases, such as gonorrhea, syphilis, herpes, and chlamydia. These may weaken the body, perhaps making it even more susceptible to the AIDS virus. Recreational, or illegal, drug use, too, may make the body less resistant to AIDS.
Also, in underdeveloped lands the lack of good nutrition due to poverty and the lack of adequate health-care facilities works against the building of the body’s resistance to AIDS. The health of hundreds of millions in those areas is already substandard, making it easier for the virus to claim additional victims.
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White T-cells of the body’s immune system normally fight off harmful invaders