Child's health Health

Fever in babies and children: the complete guide

fever - Host and Care Medical Journal

Fever in babies is a common symptom and may appear many times a year. What is considered high fever? What are his symptoms? How do you measure heat? How are you treated? When to see a doctor? How long will it take for the child to recover? Why does fever up to the age of 3 months require special attention? Our expert answers.

A fever is a temporary increase in body temperature in response to a medical condition. There are many reasons for an increase in body temperature, but the most common is infection.

The fever in itself is not a disease but one of the manifestations of the disease, which serves as a defence mechanism of the body against various pathogens such as bacteria and viruses.

Up to the age of 3 months, and especially in the first month of life, fever in a baby is treated very seriously because of the fear that it is a manifestation of a serious illness.

What is fever?

A fever is a temporary increase in body temperature in response to a medical condition. There are many reasons for an increase in body temperature, but the most common is a state of infection. 

Fever in babies is a common symptom and may appear many times throughout the year, especially in children staying in nurseries, day care centre, kindergartens and schools.

What is considered high fever in babies and children?

The normal body temperature varies from person to person and at different times of the day.

The definition of high fever in adults is a temperature above 37.5 degrees. In children, especially babies, a temperature of more than 38.2 is usually considered a high fever.

However, high fever does not become dangerous in itself below a temperature ranging from 40 degrees to 41.5 degrees (hyperpyrexia). Brain damage as a result of heat usually will not occur in a temperature lower than 42 degrees.

What causes fever?

The fever in itself is not a disease but one of the manifestations of the disease; It serves as a defense mechanism of the body against various disease-causing agents such as bacteria and viruses and is designed  to help the immune system to fight them in the best possible way and destroy them.

The temperature regulation in the body is done in the hypothalamus gland (in Hebrew: hypothermia). The hypothalamus raises the body temperature in response to pyrogens – substances that the immune system secretes into the bloodstream in various stressful situations such as viral and bacterial infection, non-infectious inflammatory processes, dehydration or damage to certain tissues.

Even though the fever is a symptom of the disease and not the disease itself, and even though it brings benefit in the fight against viruses and bacteria, in cases where the rise in body temperature is accompanied by symptoms such as headaches, chills, muscle pain, restlessness and nervousness, it is customary to give treatment to reduce the fever.

JS emphasized that the heat treatment does not cure the underlying disease but is mainly intended to improve the general feeling of the child.

In addition, it must be remembered that the effect of the antipyretic drug is temporary (4 to 6 hours), so it is sometimes necessary to give several doses during the day.

What are the symptoms of fever in babies and children?

A fever has a long series of symptoms, although not all of them necessarily appear in every child suffering from a fever:

  • A feeling of coldness that can manifest itself as chills.
  • Lack of appetite.
  • Bad mood, bad feeling, difficulty concentrating, sensitivity to pain.
  • Drowsiness, restlessness.
  • Profuse sweating, especially when the temperature drops.
  • In certain situations, in children with a tendency to this, there may also be febrile convulsions.

Babies can have additional symptoms such as:

  • Vomiting.
  • Decrease in suction power.
  • Change in the nature of crying and its intensity.

Up to the age of 3 months , and especially in the first month of life , fever in a baby is treated very seriously because of the fear that it is a manifestation of a serious illness such as sepsis, urinary tract infection and meningitis . In such cases, there is usually a need for comprehensive laboratory tests and sometimes also the administration of intravenous antibiotic treatment until the results of the blood cultures are received.

Other serious symptoms that may accompany fever – such as restlessness, convulsions, respiratory distress, jaundice or a rash of any kind – can hint at the possibility of a significant infection that requires an urgent doctor’s examination, and possibly even a more comprehensive investigation and drug treatment.

how long does it last

The duration of the fever depends on the underlying disease of which the fever is one of its manifestations. Thus, for example, in inflammation of the upper respiratory tract , which is one of the common causes of fever in children, the fever may last 3 to 4 days or even longer.

How do you measure temperature in babies and children?

The heat can be felt in contact with the child’s skin, and can be measured accurately with a thermometer. There may be differences in the temperature measurement obtained from a measurement in the mouth, ear, armpit or rectum.

Although the measurement in the anus is considered the most accurate and very reliable, for safety reasons it is recommended to measure the temperature in small children in the armpit (or in the mouth, when it comes to older children and adults).

Fever in babies

Temperature measurement

Today only digital thermometers are used, as it turned out that those containing mercury are unsafe and difficult to use.

Before measuring the temperature, it is very important to disinfect the thermometer. Wash it with running water and soap and/or clean it with a cotton swab soaked in 70% alcohol. Then wait a few minutes until the alcohol completely evaporates.

There are several ways to measure heat:

Measurement in the armpit
The thermometer must be pressed against the child’s skin and make sure that the hand is pressed against the body for the entire measurement time, and that the thermometer is constantly in contact with the skin. The process ends with the beeping of the thermometer, after about 30 seconds.

Oral temperature measurement In this method, the cooperation of the boy or girl is important. Make sure that the thermometer is placed under the tongue, and the mouth remains closed for the entire measurement time, until you hear the beeping of the thermometer.

Measuring temperature in the ear or forehead using a digital device

This is the most convenient measurement for the child, but it has a notable drawback: it is not always accurate. The measurement is done according to the manufacturer’s instructions.

When to measure temperature? 

The need for measurement is determined according to the child’s condition: if the child is vital, plays, cooperates, drinks – there is no need to measure his temperature at all. You can still take a temperature, if you feel that the child is hot.

If the child feels a bit lethargic and sleepy and does not cooperate, do not measure his temperature. If his condition does not improve after the administration of antipyretic medicine, it is recommended to measure his temperature again some time after the administration of the medicine (after half an hour to an hour).

It is important to know:  antipyretic medicine starts working only within half an hour to an hour after it is given.

How do you diagnose the cause of fever in babies?

Fever in babies (newborn)
As mentioned, in newborns up to the age of one month, the reference to fever in babies is always serious. In such a case, lowering the fever is not enough, but a comprehensive investigation should be done with the aim of establishing the cause of the fever and treating it as early as possible.

The laboratory investigation includes blood count , blood culture and additional blood tests as needed, urine test and urine culture. Sometimes it is also necessary to perform a lumbar puncture to rule out the presence of bacteria or viruses in the spinal cord fluid. If necessary, imaging tests such as a chest x-ray are also performed .

After the investigation is completed, it is customary to hospitalize any newborn who suffers from a fever and begin intravenous antibiotic treatment until answers are received regarding the blood, spinal fluid and urine cultures. If all the cultures obtained are negative, and if the baby’s general condition has improved, he will be released for further follow-up with the attending pediatrician.

Fever in babies (3 months old and older)
at these ages depends on the clarification of the baby’s general condition, the additional symptoms accompanying the fever in babies and the need for additional tests to diagnose the cause of the disease. Such children can also be diagnosed by the paediatrician at the clinic. He will take an impression of the child’s condition, diagnose the cause of the fever and provide appropriate treatment. If necessary, additional tests will be done at the clinic or the baby will be sent for further examination at a hospital.

How do you treat fever in babies?

Non-drug treatment
• Dress the child in light clothing.

• Ensure a ventilated room. On hot days we use a fan or an air conditioner.

• Give the child a lukewarm bath at a temperature of 36 to 37 degrees. It is not recommended to take cold baths that will cause the child unnecessary suffering. It is not recommended to put alcohol compresses as their harm may be greater than their benefit.

The drug treatment

The conventional medicines for reducing fever in babies are marketed as syrups or suppositories (rectal suppositories). They contain acetaminophen (some of the trade names of acetaminophen: Novimol, Paracetamol, Paracetamol Forte) or ibuprofen (some of the trade names of ibuprofen: Norofen, Advil, Ivo). It is not recommended to give children medicines such as aspirin or Opthalgin (Diphyron).

If the fever in babies is not high (up to 38.5 degrees) and if the child has not suffered from febrile convulsions in the past, and he feels well, he does not have to be given antipyretic medicine. In most cases, there is also no obligation to wake the child up to give him medicine to reduce fever in babies.

The recommended dose of acetaminophen is 10 to 20 milligrams per kilogram of body weight, every 4 hours and no more than 5 doses a day.

The recommended dose of ibuprofen is 5 to 10 milligrams per kilogram of body weight every 6 hours and no more than 3 times a day.

It is very important not to exceed the permitted dose, and it is equally important to maintain the recommended time interval between doses. An overdose may endanger the child.

What to do if the fever in babies does not go down completely even after giving medicine?
In most cases the temperature does not drop to a completely normal level, but usually a drop of one degree is enough to relieve the child.

If, despite all treatments, the fever still remains high, or if the child suffers from febrile convulsions, you can also take a bath in lukewarm water or give a medicine from another family – if the necessary period of time has not yet passed since the administration of the previous dose of medicine (for example, if paracetamol was given before, you can give it now Nurofen, but it is advisable to get a detailed explanation from the attending physician to make sure that you fully understand how to drive and avoid mistakes).

When to see a doctor?

If it is not a particularly high fever, and if the child is over 3 months old, and is alert and vital, eats as usual, and there is no change in his behavior, you can monitor him at home for a day or two before deciding whether to take him to the doctor.

On the other hand, in the following cases it is recommended to consult a doctor:

• When it comes to a baby who has not yet turned 3 months old. At this age, any baby suffering from a fever higher than 38 degrees should be brought to the doctor as soon as possible. In many cases babies of this age who have a fever will be sent to the hospital for an examination to rule out an infection which requires the immediate administration of antibiotics through the vein.

  • Older babies should be taken to the doctor if the high fever (over 38.5 degrees) lasts for more than two days in a row.
  • When the child looks sleepy, and his appetite is poor.
  • When febrile convulsions appear.
  • When the child suffers from shortness of breath .
  • When there are rashes on the skin in the form of bleeding or hemorrhages that do not disappear when the skin is pressed or stretched.
  • When the child rarely drinks or in cases where he also suffers from vomiting or diarrhea . In such cases the child rarely urinates, and the diaper remains dry. A dry diaper over time should always raise the suspicion that it is dehydration.

What to do when the child has no appetite during the illness?

Sick children, like sick adults, often have a poor appetite during a fever. This should not cause concern, as the appetite will return when they recover, and they will make up for all the food they are missing.

On the other hand, drinking must not be given up, since the heat causes increased fluid loss, and the child is exposed to the risk of dehydration. Make sure that the child drinks a lot (any drink he wants – the main thing is that he drinks) and make sure that he urinates.

Could there be complications?

As mentioned, high fever is usually not dangerous, so you can be calm about the meaning of fever in itself. The complications, if any, will – most likely – result from the underlying disease and not from the fever. 

An exception is a condition of heat above 40 degrees. It is recommended to lower it with medication for fear that it will continue to rise to the dangerous level. 

It should also be remembered that fever can sometimes be a sign of non-infectious diseases such as non-infectious arthritis, autoimmune diseases and other significant diseases. In any case, a prolonged fever requires a medical examination.

What are febrile convulsions?

Febrile convulsions are a phenomenon suffered by children with an innate tendency to it between the ages of 6 months and 5 years when they have a fever. Febrile convulsions are usually caused by a rapid and sudden increase in the child’s temperature in the first stages of the febrile illness and usually last a short time – no more than five minutes. Of course, not every febrile illness necessarily causes a febrile convulsion even in children who have a tendency to it.

Although this is an alarming situation, it must be remembered that usually the main danger does not lie in fever or convulsions, but in the disease that causes them. This danger is especially serious in babies less than two months old, whose serious illnesses may be manifested only by heat. From the collected data it appears that between 12% and 28% of the newborns who came to the pediatric emergency room because of a fever were sick with dangerous diseases such as sepsis, pneumonia, meningitis, bone or joint inflammation.

Although a febrile convulsion is a very scary phenomenon, there is usually no reason to panic, and it must be remembered that the child will not suffer brain damage. However, it is advisable for a doctor to examine a child who has had a febrile convulsion, at least the first time the phenomenon is encountered. It must be remembered that a child who squirms once may squirm again, although with the increase in age the phenomenon passes by itself.

Caution: If the convulsion lasts more than five minutes in a row, or if there are several shorter convulsion events in the same day, the child should be rushed to the hospital for further investigation and treatment.

In how long will the child “come back to himself”?

Children usually recover as soon as the temperature starts to drop and even before it reaches its normal level. It must be remembered that the decrease in fever does not necessarily mean the disappearance of the disease, so there may be cases where the fever has passed, but the child is still weak, lacks appetite, suffers from rashes and diarrhea, etc.

will it come back

It is very likely that the heat will repeat itself. Heat illnesses are very common and accompany us throughout our lives.


High fever is not the disease itself, but the body’s reaction to the disease. By itself, it usually doesn’t mean much. If the child feels well apart from that, there is no obligation to lower the temperature. If the child is not feeling well, it is worth lowering the fever to relieve him, although this does not shorten the illness or change its course.

Mammography: Advancements in Breast Cancer Screening Complete guide: CT scan of the brain Artificial Sweeteners: Sucralose vs. Aspartame National French Fry Day : Healthy Recipe 6 signs of oral cancer you can identify Skin cancer signs and prevention