Fever symptoms, causes and treatment

A rise in the body’s temperature above the normal range is a Fever. The increase in temperature is usually due to an infection. The average body temperature is 37°C. There are minor fluctuations over the day and night. Unlike what most people think, the severity of a fever is not necessarily associated with the seriousness of the underlying illness. For instance, life-threatening meningitis only causes a small rise in your temperature.  

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A fever may also be triggered by a viral or bacterial infection caused by chemicals in the immune system. The body’s thermostat is reset to a higher level. In most cases, a mild fever resolves itself in a few days. A mild fever ranging from 37.1°C to 39°C may help the immune system in ridding off the infection. On a serious note, fevers can trigger convulsions in children between ages six months to six years. In the elderly, a temperature of 42.4°C or higher, can lead to permanent damage to the brain. 


When a person has a fever, there are signs and symptoms that you can link to the usual sickness behavior. It may include any of the following:

  • Lack of appetite
  • Shivering
  • Depression
  • Feeling cold 
  • Dehydration
  • Hyperalgesia or a heightened sensitivity to pain
  • Problems concentrating
  • Lethargy
  • Sweating
  • Sleepiness

For high hay fevers, the patient may also experience confusion, irritability, seizures, and delirium. 

Causes of Fever

Several things can cause a rise in the body’s temperature. Some factors that cause fever include:

  • Rheumatoid arthritis
  • Infections like flu, strep throat, pneumonia or chickenpox
  • Sunburn or the overexposure to sunlight
  • Dehydration
  • Heatstroke, due to exposure to high temperature or strenuous activities
  • Amphetamine abuse
  • Silicosis
  • Alcohol withdrawal

Different Types of Fever

Fever is differentiated based on their severity and the length of time that you have it. For the severity, a fever can be:

  • Low-grade – range from 38.1–39°C (100.5–102.1°F)
  • Moderate – range from 39.1–40°C  (102.2–104.0°F)
  • High – range from 40.1-41.1°C (104.1–106.0°F)
  • Hyperpyrexia – 41.1°C (104.1–106.0°F) 

Depending on the range of temperature, it may indicate the underlying cause of the fever.  For the length of time, a fever can be: 

  • Acute – if it lasts no more than seven days
  • Sub-Acute – it lasts for up to fourteen days
  • Chronic and persistent – last for more than 14 days

Fever in ChildreN 

Children having a very high fever may develop a febrile seizure. This condition is also called the febrile convulsion or febrile fit. In most cases, seizures are not severe and may be due to gastroenteritis, respiratory virus, and ear infection. It is less common for a febrile fit to be due to severe conditions like pneumonia, meningitis, or kidney infection. 

Febrile fit is typical in children from six months to six years, and it occurs more commonly in boys than in girls. Seizures happen due to the fast rise in body temperature. It is not because the fever is sustained for an extended period. 

There are two kinds of febrile fit: 

  1. Simple Febrile Seizure – most cases of this seizure last from 5 to 15 minutes. It does not happen again in 24 hours. It usually affects the whole body in a tonic-clonic convulsion. The body will stiffen, and the arms and legs begin to twitch. The child may lose consciousness, however the eyes may remain open. Also, there may be irregular breathing. More so, the child might vomit or involuntarily urinate or defecate or both.  
  1. Complex Febrile Seizure – this type of seizure is longer and recurs more often. It does not tend to involve the whole body; instead, it occurs in some parts only. Likewise, this type of seizure in children may have a more serious underlying cause than the first type. 

A child having a seizure should be seen by a healthcare provider. The rising temperature can be managed with paracetamol or acetaminophen. Sponging will also help lower the fever. If necessary, anticonvulsants will be given. 


Diagnosis and Treatment

Forward is easily diagnosed – by taking the patient’s temperature. If the patient’s reading is high, then it indicates a fever. Taking temperature should be done while the patient is at rest. Our physical activity may increase the body’s temperature. A person has a fever when thermometer reading shows slight elevations on the average temperature.  

After confirming that the patient has a fever, the doctor may order several diagnostic tests.  Depending on the existing signs and symptoms that accompany the fever, the tests may include urine tests, blood tests, X-rays, and other tests.  

Treatment of Fever

The use of non-steroidal anti-inflammatory drugs (NSAIDs) like aspirin and Ibufrupen will help lower the body’s temperature. These are available over the counter or online. On the other hand, a mild fever may help combat bacterial or viral infection; thus, it may not be a good idea to bring down the fever.

If the doctor has diagnosed the fever to be due to a bacterial infection, the doctor may prescribe an antibiotic.  If it is caused by a cold, which is due to a viral infection, NSAIDs can help relieve symptoms. Antibiotics will not work against viruses, and it will not be prescribed for viral infections. 

Patients with fever should increase their fluid intake to prevent dehydration. When the body temperature is elevated, there is a risk of dehydration, which may complicate the illness. 

If the fever is due to heatstroke medications will not work to bring it down. The patient needs to be cooled. If they are unconscious or confused, they should be attended to by a doctor immediately. 

What are the normal conditions? 

The average body temperature varies, and it is affected by different factors like sleeping, exercise, eating, and the time of the day. The body temperature is at its highest at about six in the evening. Likewise, it is at the lowest at around three in the morning. 

A fever or a high temperature is one of the ways that our body’s immune system fights an infection. Generally, a rise in body temperature helps a person resolve the infection. However, it may rise too high, causing a severe fever, which may lead to complications. 

As long as the fever is mild and not severe, doctors agree that there is no need to bring it down. It is probably helping the body fight bacteria or virus that is causing an infection. If a fever is causing discomfort, medication to bring it down may be prescribed.

A fever that is beyond 38° C is no longer mild and needs to be monitored every couple of hours.     

Risks of Having A Fever

Fever may occur when the hypothalamus shifts the body’s average temperature upwards. It is one of the ways that the body fights an infection. A person with a fever will feel chilled and shiver to generate more body heat. Many conditions trigger a fever. If you have any of these conditions, you are more likely to run a high temperature. 

  • Teething in infants
  • Immunization or vaccinations 
  • Inflammatory diseases such as Crohn’s disease and rheumatoid arthritis
  • Infections such as flu or pneumonia
  • Extreme sunburn
  • Blood clot
  • Food poisoning
  • Medications 


When to Seek Medical AttentioN 

In most cases, a mild fever is treated at home. But if the fever is accompanied by symptoms that indicate a severe medical condition, it requires immediate treatment. 

For infant fever, take them to the doctor in case of the following conditions: 

  • If the infant is younger than three months with fever exceeding 38°C
  • If the baby’s age is three to six months with temperature readings of 38.9°C and with symptoms such as lethargy, irritability, and discomfort. 
  • If the baby’s age is six to 24 months with a fever higher than 38.9°C that lasts longer than one day. 

For fever in children, you should take them to the doctor if:

  • The child has body temperature exceeding 39°C
  • Makes poor eye contact
  • Has a fever for more than three days
  • Had one or more immunization recently
  • Irritable and restless
  • Have a severe medical condition or a weakened immune system
  • Has recently visited a developing country  

For fevers in adults, you should call the doctor if

  • Your body temperature exceeds 39.4°C
  • Your fever is more than three days
  • You had recently visited a developing country
  • You have a severe medical condition or a weakened immune system  

Likewise, you should also see a doctor if you or your child’s fever has the accompanying symptoms- 

  • Swollen throat
  • Skin rash that is getting worse
  • Severe headache
  • Persistent vomiting
  • Stiff neck or neck pain
  • Sensitivity to bright light
  • Abdominal pain
  • Muscle weakness
  • Irritability
  • Confusion
  • Painful urination
  • Trouble breathing and chest pain

The doctor will perform physical examination and tests to help them determine the cause of the fever. With the proper diagnosis, they will be able to provide an effective course of treatment for your condition.

A fever becomes a medical emergency if you or your child experience the following symptoms:

  • Inability to walk
  • Confusion
  • Chest pain
  • Trouble breathing
  • Seizures
  • Inconsolable crying 
  • Hallucinations

Proceed to the nearest emergency medical services or call 911 in case of fever that is accompanied by these symptoms.