Fever

Fever, or pyrexis, is a condition in which body temperature rises above the normal. Mild fevers are associated with loss of liquid and chills, while more extreme fevers can lead to convulsion and even death. Generally, a fever is caused as a result of infection by virus or bacteria and results from the body's natural ability to produce more pyrogens than normal and these affect the brain's ability to detect temperature changes. It is possible that fever can be a beneficial response by the body to an infection and helps in resistance and recovery from it. However, this has not yet been fully established and some controversy surrounds the issue. Nevertheless, the elevated temperatures stimulate the production of white blood cells and may inhibit the growth of invading organisms.

During the course of a typical day, the internal temperature varies little and generally remains within one or two degrees of its average of 37.2 degrees C in the mouth; increases in temperature beyond this range are, therefore, defined as fever and temperature rises of above 40.5 degrees represent severe fevers; should the temperature reach 42.2 degrees or higher, then a genuine threat of death exists. Mild fevers generally feature increased sweating and reduced blood and urine production.

Although fever is generally associated with viral infection, it can also come about as a result of coronary trouble or in response to extreme physiological stress. In general terms, treating fever should be approached by treating the underlying causes of the fever, although this may be accompanied by measures to reduce any discomfort the patient might be feeling as a result of high temperature. Consequently, aspirin might be used as an antipyretic agent and other pharmaceuticals used to tackle the cause and nature of the infection or other cause.

A wide range of conditions are referred to as a form of fever, not always accurately. The name of the fever generally relates to its cause; for example, Rift Valley fever is caused by the bite of mosquitoes in the Rift Valley of Kenya and subsequently more widely; meanwhile, blackwater fever is a form of malaria in which the urine turns black. Hay fever is a condition in which an allergic reaction to pollen or similar item leads to flu-like symptoms, although strictly speaking this is not a fever at all. In many parts of the world, fevers continue to represent a serious threat to health. Dengue fever, for example, and hemorrhagic fever kill tens of thousands of people annually. Increases [Page 664]in public health technical capacity and resources in affected countries would help to reduce these numbers. However, as climate change continues to cause migration of living creatures into different locations, vulnerability will spread beyond areas where those problems have previously been experienced.

Fever is caused as a result of infection by virus or bacteria and results from the body's natural ability to produce more pyrogens.

JohnWalsh, Shinawatra University