जानिए! बुखार क्या है ? What Is a Fever?

Author : Dr. P. D.GUPTA

(Former Director Grade Scientist, Centre for Cellular and Molecular Biology, Hyderabad, India)


In the enthusiasm to kill the invading infestations   a very tiny spot in the brain called the hypothalamus which is responsible for controlling the body temperature raises body temperature.   So when a fever comes on, it’s an indicator   something abnormal activity is going on in the body.  Fever is an elevated temperature of the human body that is substantially beyond the normal range. Sometimes, you may have a "fever of unknown origin." In such cases, the cause could be an unusual or not obvious condition such as a chronic infection, a connective tissue disorder, cancer, or another problem. 

Normal body temperature 

Normal human body temperature is 98.6+/-1  degrees Fahrenheit (370C)  . Lower body temperatures usually occur before dawn; higher temperatures in the afternoon..  Normally, we measure body temperature by keeping thermometer either in mouth or armpit, here the temperatures is approximately actual body temperature and are more convenient to measure. However skin (surface) temperature is lower and Rectal (internal) temperature tends normally to be higher than. 

Causes of Fever  

A fever can be a sign of several health conditions, which may or may not need medical treatment. A viral or bacterial  infection, Heat exhaustion(Sunburn), certain inflammatory conditions such as rheumatoid arthritis — inflammation of the lining of your joints,   presence of cancerous (malignant) tumour, Some medications, such as antibiotics and drugs used to treat high blood pressure or seizures can also cause fever. Vaccines and immunizations Hormone disorders such as hyperthyroidism, Infectious agents are not the only causes of fever, however. Amphetamine abuse and alcohol withdrawal can both elicit high temperatures, for example. And environmental fevers--such as those associated with heat stroke and related illnesses--can also occur.Teething in babies can cause a mild, low-grade fever 

Mechanism of rising Temperature 

The hypothalamus, which sits at the base of the brain, acts as the body's thermostat. It is triggered by floating biochemical substances called pyrogens, which flow from sites where the immune system has identified potential trouble to the hypothalamus via the bloodstream. Some pyrogens are produced by body tissue; many pathogens also produce pyrogens. When the hypothalamus detects them, it tells the body to generate and retain more heat, thus producing a fever. Children typically get higher and quicker fevers, reflecting the effects of the pyrogens upon an inexperienced immune system. 

Fever Symptoms 

Fevers are signs of some sort of illness or infection. When you have, you may also notice these symptoms: Chills or shivering, Sweating, Headache, Feeling weak, Being irritable, Losing your appetite, Being dehydrated 

Should one eat little or nothing while feverish?  

 "Feed a cold, starve a fever" . Yes. The reasons for this are threefold. First, during fever, all the body's functions are occurring amidst increased physiologic stress. Provoking digestion during physiologic stress over stimulates the parasympathetic nervous system when the sympathetic nervous system is already active. Second, it is possible that the body could misinterpret some substances absorbed from the gut as allergens during a fever. Finally, excessive fever can, on rare occasions, cause seizures, collapse and delirium--all of which may be further complicated by recent eating. 

Fever management 

Fever is usually associated with physical discomfort, and most people feel better when the temperature is brought down. But depending on   age, physical condition, and the underlying cause of your fever, one may or may not require medical treatment for the fever alone. Many experts believe that fever is a natural bodily defense against infection. There are also many non-infectious causes of fever. 

Treatments vary depending on the cause of the fever. For example, antibiotics would be used for a bacterial infection such as strep throat. The most common treatments for fever include over-the-counter drugs such as acetaminophen and non-steroidal anti-inflammatory drugs such as ibuprofen and naproxen. Children and teens should not take aspirin because it's linked to a condition called Reye’s syndrome. 

Ways to lower a fever at home include: 

Drinking a lot of clear liquids such as water, broth, and juices or a rehydration drink 

Taking a lukewarm bath 


Keeping yourself cool with lightweight clothing and bed coverings 

Fever can help fight infection, but sometimes it can climb too high for the body's own good. Internal body temperatures in excess of 105 degrees F, for instance, expose proteins and body fats to direct temperature stressors. This form of heat distress can threaten the integrity and function of proteins accustomed to the body's usual temperature variations and the occasional less excessive fevers. Cellular stress, infarctions, necrosis, seizures and delirium are among the potential consequences of prolonged, severe fevers. The receptor environment at the hypothalamus maintains limitations on high fevers. In the rare instances in which the hypothalamus itself malfunctions, the result is typically low body temperature, not elevated body temperature. (The author has his own study and views)