There are four types of fevers can be identified when they are categorized based on the height of temperature. These include:
- Mild/low-grade fever. A low-grade fever happens when the body temperature rises to 100.4F (38C)
- Moderate grade fever. Moderate fever if the temperature rises above 102.2-104F or 39.1-40C
- High-grade fever. High-grade fever indicates if the body temperature is 104F (39.4C) or above.
- Hyperpyrexia. Hyperpyrexia is when the temperature is above 106F or 41.1C
This does not necessarily mean that there are only four types of fevers. Many more types of fevers may be identified depending on how they are categorized. Here are some examples:
Temperature pattern: Fevers can be classified based on their temperature pattern, such as intermittent, remittent, and sustained.
- Intermittent fevers come and go, with periods of normal temperature in between.
- Remittent fevers fluctuate but never return to normal temperature.
- Sustained fevers remain at a constant elevated temperature without any fluctuations.
Duration: Fevers can be classified as acute, subacute, or chronic depending on their duration.
- Acute fevers last for a short period of time (usually less than seven days).
- Subacute fevers last longer than acute fevers but shorter than chronic fevers (usually between one and three weeks).
- Chronic fevers last for more than three weeks.
Cause: Fevers can be classified based on their underlying cause, such as infectious or non-infectious.
- Infectious fevers are caused by an infection, such as a bacterial or viral infection.
- Non-infectious fevers can be caused by conditions such as autoimmune diseases or cancer.
Other factors: Fevers can also be classified based on other factors such as the age of the patient, the severity of the fever, and the presence of other symptoms or medical conditions. For example, fevers in infants and young children may be classified differently than fevers in adults, and a high fever accompanied by severe symptoms may be classified as a medical emergency.