Before referring a fever temperature chart, it is important that you know the various ways through which you can measure the body temperature of an individual. You can measure temperature orally (via mouth), axillary (through armpits), rectally (through rectum or anus) or tympanic (via ears).

The temperature readings differ based upon where you have measured it. It still isn’t determined as to which way is the most efficient way to read body temperature of an individual and what is the exact correlation of different temperature readings taken orally, axillary, rectally or tympanic, or even siumply through forehead.

• Average body temperature is approximately 37 degrees Celsius or 98.6 degrees Fahrenheit.
• Temperature taken rectally is 0.3 degrees Celsius to 0.6 degree Celsius higher than an oral temperature.
• Armpit temperature is similarly 0.6 degree Celsius higher than oral temperature.
• A temporal or forehead scanner shows the same result when compared with oral temperature reading.

A fever temperature chart illustrates the various range of body temperature and helps us decide if a person under observation is suffering from fever.

A basal body temperature of an individual is defined as the lowest temperature attained by the human body during rest or during sleep. It is usually measured just after awakening. The body temperature of women usually differ during various points such as menstrual cycle.

Core body temperature is the operating temperature of a body or an organism. It is specially related to deep structures of the body such as liver, when compared with other peripheral tissues. The temperature is normally maintained within the narrow range for essential enzymatic reactions to occur.

Hyperthermia is usually not considered as fever. It is the high temperature caused due to symptoms such as neuroleptic malignant syndrome, idiosyncratic drug reactions, heatstroke, and due to stimulants like amphetamines or cocaine.

Since hypothermia is a sudden drop in the body temperature (below 95 degrees Fahrenheit), it can quickly become life threatening. This is because, certain organs require a specific body temperature to function and carry out enzymatic reactions, failure of which could result in organ failure. Hypothermia usually occurs due to sudden cold exposure. It occurs when the body fails to balance the core temperature of the body due to exposure of very low external temperatures.

Fever is actually an immune response of the body to the pyrogens. These pyrogens usually come from an outside source. Pyrogens that have entered the body via a bacterial, viral or fungal infection stimulate the production of additional pyrogens (with the help of hypothalamus) in the body, thereby increasing the body temperature beyond set point.

Some facts about body temperature state:

• Body temperature varies throughout the course of the day.
• A temperature beyond 38 degrees Celsius means that the person might be suffering from fever caused by an illness or an infection.
• Medically accepted normal body temperatures range between 36.5 to 37.5 degree Celsius.
• Fever can be graded due to both high body temperature hyperthermia, or low body temperature which is also termed as hypothermia.
• A special thermometer is used when the body temperature is measured tympanic, that is through ear. In this case, the temperature of the eardrum reflects body’s core temperature.

The American Academy of Pediatrics (AAP) defines the normal body temperature of a baby to be between 97 degrees Fahrenheit and 100.3 degrees Fahrenheit. If the rectal temperature in babies is beyond 100.4 degrees Fahrenheit, they are considered to have fever.

The fever temperature chart is classified under these four temperature categories:

• A fever is said to be hypothermic if, the body temperature is below 35 degrees Celsius or 95 degree Fahrenheit.
• The normal body temperature ranges between 36.5 and 37.5 degrees Celsius or 97.7 or 99.5 degrees Fahrenheit (this temperature range is different for babies and children.
• Hyperthermia which is usually caused due to an illness or an infection ranges between 37.5 degrees Celsius or 101 degrees Fahrenheit.
• Hyperpyrexia or exceptionally fever is caused when body temperature shoots up above 41.5 degrees Celsius or 107 degrees Fahrenheit.

Using the fever temperature chart, other fever and fever types are describes as:

• A prolonged or a persistent fever is a long lasting fever that can last for about 10-14 days. This usually a low-grade fever.
• Acute fever is a fever occurred due to onset of an illness. This is the most usual type of fever.
• Chronic fever lasts more than 4 days. Chronic and intermittent fever could be the result or a symptom of a much greater disease rather than a simple infection. This because chronic or intermittent disease lasts for 3 – 4 days and reoccurs for over months.
• Remittent fever occurs at regular intervals. Hyperpyrexia is condition in which the body temperature is way above the condition of hyperthermia and constitutes for immediate medical emergency.

There are over 40 diseases that have fever as a part of its disease name. Some of this include: rheumatic fever, scarlet fever, Lassa fever, cat scarlet fever etc.