Sunday, January 6, 2008

The Importance of Fevers

I've been telling people about the importance of fevers for years and then today I discovered this gem of an article while searching for something else on the Internet. I just HAD to share it with you!

Published: December 28, 1982

THE ancient Greeks, who regarded disease as an imbalance of ''humors,'' believed fever cured the sick by cooking the bad humors and helping the body get rid of them. The notion of fever as beneficial persisted for more than 2,000 years, and countless patients were actually treated with ''fever therapy'' to aid their recovery from such ailments as syphilis, tuberculosis and even mania.

Then, in the mid-1800's, aspirin compounds that rapidly reduced fevers became commercially available and the medical view of fever changed abruptly. For the next hundred years, physicians and patients focused on bringing down fevers, sometimes with such drastic measures as cold baths and alcohol rubs.

Now, the view of fever is undergoing yet another about-face, thanks to recent research that has in essence documented the benefits suspected by the Greeks. Fever, the studies indicate, evolved at least 300 million years ago in cold-blooded vertebrates as a means of helping the body fight off invading organisms.

The new findings raise serious questions about the wisdom for most people of taking aspirin or acetaminophen for fevers below 104 degrees. Indeed, a number of physicians, including pediatricians, are now suggesting that moderate fevers be allowed to run their course, for they may shorten the illness, potentiate the action of antibiotics and reduce the chances of spreading the infection to others.

These doctors say that fever-reducing drugs should be used with discretion, and some experts even foresee the return of induced fevers to treat selected illnesses. A form of fever therapy is being used experimentally as part of the treatment for some cancers.

Fever, the new studies show, mobilizes the body's immunological defenses against infectious organisms and, in some cases, directly inhibits their growth. Experiments with infected animals, such as fish, lizards, rabbits and dogs, show that those that are allowed to raise their body temperatures are more likely to survive.

In one of the latest studies, people who exercised vigorously were shown to experience some of fever's effects, which may account for claims of physical fitness buffs that they are less susceptible to ordinary viral and bacterial infections.

''Fever has a high energy cost to the individual,'' said Dr. Matthew J. Kluger, a physiologist at the University of Michigan Medical School and one of the leading researchers in the revisionist view of fever. ''For each 1-degree rise in Centigrade temperature, the body's metabolic rate increases about 10 percent - heart rate, respiration, all the metabolic functions are speeded up.''

He added that for this costly response to infection to have been retained throughout the evolution of vertebrates, ''it must have a net survival value.'' In other words, infected animals that developed fever would, on average, have a better chance of living and passing their genes on to the next generation.

The new understanding of fever grows out of basic studies, sponsored primarily by the National Institutes of Health, that have revealed how fevers develop and what changes they induce in the body. Various substances can prompt the development of a fever, among them viruses, bacteria, fungi, toxins, allergens and certain drugs. When the immune system detects such a foreign invader, a type of white blood cell, called a monocyte, is activated and engulfs the intruder.

The activated monocyte, now called a macrophage, releases a hormone, endogenous pyrogen, or EP, which travels through the bloodstream to the brain. There, EP acts on a region of the hypothalamus that regulates body temperature, and raises the body's thermostat, or temperature ''set point.'' The body, which now is not as warm as the brain says it should be, feels chilled and, in effect, turns on its furnace to raise body temperature to the new setting.

Nerve messages originating in the hypothalamus trigger rapid muscle contractions, or shivering, which produce heat. Other nerves constrict outlying blood vessels to reduce heat loss to the environment. Body tissues, such as stored fat, are broken down to produce heat. And the sensation of coldness stimulates behavior, such as putting on warm clothes, piling on covers or drinking hot liquids, that also help to raise body temperature. ...

To read more link to: The New York Times

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