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what is feaver caused by?
are there any degrees of fever where it may cause death?
We're not medical doctors here, but we'll try to answer. For a serious medical answer, ask a real doctor.
Fevers are caused by lots of different medical conditions, but the ones that most of us are most familiar with are infections by bacteria or viruses. In some sense the ícauseí of the fever is that the elevated temperatures help kill at least some types of infections. That meant that people who got fevers in response to infections were more likely to survive and have children. So evolution made us have fevers. If a fever is not too severe, it may be a good idea not to suppress it with drugs like aspirin, because the fever is usually part of how we fight the infection.
On the other hand, the system doesnít work perfectly for us. High fevers can cause severe brain damge and even death. Whether thatís just because our evolution didnít work perfectly or because some infectious agents themselves evolved to cause death (perhaps because that was connected with the mechanism of their spread) is not very clear yet.
(republished on 07/17/06)
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