One of the worst fears is an attack of bioterrorism. But, a viral threat does not have to come from human evil. Viruses are common, and without proper medication or vaccination, what seems like a simple virus, such as the flu, can wipe out large sections of the population. Some viruses are new enough that cures for them have not been found. Others have seemingly been wiped out but, through artificial means are making a comeback.

Viral Infections

A virus is a small infectious organism that invades a living cell in order to reproduce. Once attached to a cell, the virus releases its DNA or RNA with its genetic material, which then takes over the original genetic material of the cell. The cell ends up dying because it cannot function with its intended purpose, but before it dies, it releases more viruses, which attack other cells, and so on until the body is infected. If the virus does not actually kill the cell it infects, it at least alters the cell’s functions.

Viruses usually attack one type of cell. A cold virus, for example, only attacks cells in the upper respiratory tract. Some viruses attack plants, some attack animals, and still others attack only humans.

When a virus enters the system, the body reacts, trying to fight it out. White cells in a human will go on the defensive against the cells infected with the virus. If the body survives the initial virus, it will build up an immune system. Vaccines work in the same manner.

Spread of Viruses

Viruses can be spread through the air and inhaled, through swallowing, or through insect bites or other parasitic infections. They can be highly contagious, particularly airborne viruses.

A virus becomes a threat when it is uncontrolled and people begin to take ill and die. A virus can wipe out large chunks of a population, especially those who are already weakened by illness, malnutrition, or poor health habits.

The major concern with a bioterrorist attack is that a virus will be released on a large population base without warning and without treatment immediately available. But a viral threat need not be simply from a man-made terrorist attack. Diseases like HIV and hepatitis threaten to wipe out generations in Africa.