Suddenly we look at our baby and see that he has rosy cheeks. We put our hand to his forehead and it feels warm, and he's acting strangely. We quickly take his temperature and our fears are confirmed: he has a fever.
At that moment, the alarms go off: What should I do about my child's fever? Should you rush to the emergency room? Should you stay home and observe? Perhaps it's not such a big deal? Understanding what a fever is, why it occurs, and how to act in each case is essential for caring for children safely and with peace of mind.
What is fever?
Although the temperature of the human body varies by time of day and there are differences from one to another, it is considered that the normal temperature of our body must not exceed 37.5ºC if we measure it in the armpit or 38ºC if we measure it in the rectum.
Fever it is not a disease, it is a symptomThis is a reaction of our body, usually caused by a viral or bacterial infectionalthough it can also appear due to other less frequent causes (some inflammatory diseases, certain medications or, in a mild form, after some vaccines).
Fever really is a defense response of our bodywhich tries to eliminate those viruses or bacteria. Germs tend to grow better at temperatures close to 37ºC, so our body raises its temperature to eliminate the causes of the fever. have a hard time living and reproducing in our body.
Furthermore, fever is responsible for activate our body's defensesbecause that temperature increase is what stimulates our immune system to produce more white blood cells and antibodies who will fight the infectionTherefore, although it is frightening, fever is part of a natural defense process and, in itself, It is not usually dangerous if handled properly.
It is important to know that the fever itself It does not cause brain damage nor other serious injuries unless it reaches extremely high temperatures (above 42ºC, which is very rare). What should really concern us is the cause that is producing that fever and the child's general condition.
When is a child considered to have a fever?
Normal body temperature ranges approximately between 36,5ºC and 37,5ºCDepending on the time of day, the child's activity, or the clothing they are wearing, a fever is considered to be present when the temperature is above:
- 38ºC if it is measured in the rectum (rectal temperature).
- 37,5ºC if it is measured in the mouth (oral temperature).
- 37,2-37,5ºC if it is measured in the armpit (axillary temperature).
In daily practice and in most households, it is most common to talk about fever starting from 38ºC of axillary temperature, although the above values help to understand that there are small differences depending on where the measurement is taken.
Below those figures, but above normal, we sometimes speak of tenths or low-grade fever, which usually corresponds to mild processes or the beginning of an infection, and is managed mainly by observing the general well-being of the child more than the exact number on the thermometer.
Most common causes of fever in children
The most frequent cause of fever in children is a mild viral infectionIn many cases, these are colds, pharyngitis, bronchitis, otitis, or gastroenteritis, which present with fever and other associated symptoms (cough, runny nose, sore throat, vomiting, diarrhea, etc.). In young children, even minor viral infections can cause high fever spikes.
Other common causes include:
- Bacterial infections such as some ear infections, pneumonia, urinary tract infections, or other localized infections. They usually require medical evaluation to determine if antibiotic treatment is necessary.
- Recent vaccinationsIt's normal for this to appear after some vaccinations. low-grade fever or mild fever for a few hours or a couple of days. It is usually temporary and accompanied by good general health.
- TeethingIn this case, the temperature rises very little and It does not usually exceed 37,7ºCIf there is a high fever, it is advisable to consider another cause.
- Inflammatory or autoimmune diseases, such as juvenile rheumatoid arthritis, and some malignant tumors They can cause prolonged fever, although they are much less frequent.
- Some medications, such as certain antibiotics or specific drugs, can cause fever as a side effect.
Sometimes the cause of the fever may be is not immediately knownIt is relatively common for a child to only have a fever in the first 24-48 hours, without a clear cause (no cough, no diarrhea, no localized pain). As the hours pass, other symptoms may appear, helping the pediatrician to identify the cause.
Detecting fever is very easy
Just by looking at a child, we often realize that something is wrong. Even before using a thermometer, the little one's body tells us something is wrong. very clear clues:
Usually the baby breathe faster, your heart races, your cheeks they are red, his eyes are bright… We will notice that It is very inactiveHe is shivering and complaining persistently of being cold. Furthermore, when We noticed that her forehead felt hot when we touched it., and even the torso and back can be burning hot while the hands and feet are cold.
Although touching the forehead may suggest a fever, it is recommended not deciding with just your hand and always use a thermometer to confirm it. This helps to:
- Assess whether there is actually a fever or just heat due to overdressing or a very hot environment.
- Register the temperature figures and its evolution, very useful information for the pediatrician.
- Avoid unfounded fears when the temperature is only slightly elevated.
To confirm whether or not the baby has a fever, the best way is use a good thermometer and follow correct measurement guidelines.
The ideal thermometer for measuring fever
A few years ago they retired the classic mercury thermometers They were replaced by other models, which were safer and easier to use. Below we review the most common ones.
Digital thermometers
Digital thermometers are the most recommended nowadays. They are usually quite accurate. fast and accurateTheir shape is reminiscent of mercury thermometers, and their placement for taking temperatures is similar. They are commonly used for take the temperature in the armpitalthough there are models that also allow it to be taken rectally or orally.
To obtain a good axillary measurement, it is advisable to:
- Dry your armpit thoroughly if there is sweat, so that the reading is clear. more reliable.
- Place the tip of the thermometer in direct contact with the skin, not on clothing.
- Keep the child's arm close to the body during 1-2 minutes or even the device's sound signal.
Electronic ear or forehead thermometers
Electronic thermometers (ear or infrared forehead thermometers) are very useful in adults or older childrenbecause they allow you to measure temperature in just a few seconds. However, their use in babies or young children is not recommended. it is not very advisable In some models, this is because they can lose accuracy if they are not placed perfectly or if there is earwax or other factors.
Their price is usually higher, and if they are used, it is important strictly follow the instructions from the manufacturer to reduce measurement errors.
Plastic strips to measure the temperature on the forehead
They were very popular a long time ago, but today they are considered not very useful and very inaccurateIts reading can vary greatly with ambient temperature or skin perspiration. Therefore, it is It's much better to use another method., like a conventional digital thermometer.
Where to put the thermometer
Although you can take the temperature in the mouth, anus, or armpitIn our environment, the most common thing is take it in the armpitI can assure you that, in my many years of experience and work in different hospitals, it is the only temperature that is routinely assessed by professionals: the axillary temperature.
It should also be noted that keeping the child with the thermometer still in the mouth without spitting it out or hitting it with the teeth is very difficult Taking a temperature rectally involves holding the baby with the thermometer in place. This is complicated, and there's always the risk that the struggle we'll likely have to keep the baby still could cause the thermometer to malfunction. inserting the thermometer too far into the anus.
In infants, rectal temperature measurement can be useful in a healthcare setting and under professional supervision, but for home use it is generally recommended to axillary measurement with a digital thermometer as a safer and more convenient option.
Is it always necessary to treat a fever?
Fever is a symptom, not a disease. So what we have to deal with is the disease causing the fever and, above all, the child's discomfort.
The Spanish Association of Pediatrics (AEP) recommends treating fever only if it causes discomfort to the childIf not, it is advised not to give them medication and Let the fever do its job as a defense mechanism.
This means it's not mandatory to try to lower even a tenth of a point. If the child is active, plays, stays well hydrated And if he doesn't seem uncomfortable, even with a slight fever, he can be observed without medication. However, if he has a headache, muscle aches, is very irritable, or has trouble sleeping, then it makes sense to use fever reducers.
It's also important to know about fever medications. They do not cure the infection.They only help the child feel better while their immune system does its job. It's normal for the fever to return once the medication wears off, especially in the first 12-24 hours of an infection. They don't need to be given continuously if the child is calm between doses.
Measures to take at home when a child has a fever
When a fever appears, the most important thing is to create an environment that facilitates the child's comfort and help your body fight the infection. These are the main steps:
1. Clothing and atmosphere
- Make sure the child is comfortable and to your likingDon't overdress him; too much clothing makes it harder for the body to lose heat.
- Keep a soft temperature in the baby's room, avoiding both excessive heat and direct drafts.
- It is preferable to have the child with light clothing or even minimal clothing, especially if the fever is high, to promote heat elimination.
2. Hydration
Offer him water and fluids frequently, as fever makes him want to... You lose fluids and can become dehydrated.. Some options:
- Breastfeeding or bottle feeding on demand for the youngest infants.
- Water, mild broths, or oral rehydration solutions for the elderly.
- Avoid sugary or stimulating drinks, which do not provide adequate hydration.
Don't force it too much, but do offer small sips regularly, especially if the child He has little appetite. or has vomited.
3. Bathrooms and physical measurements
Giving them a bath is a classic way to treat children with a fever. It's not a bad idea, but It is not necessary to bathe him with cold waterIt's better to soak it for a while in warm water and always supervised by an adultThe water should be about 2 degrees below body temperatureNever frozen, to avoid chills that can generate even more heat.
They can also be used warm, damp cloths on the forehead, nape of the neck, armpits, or groin. What is not recommended is:
- Use cloths with alcoholbecause they can be absorbed through the skin and be toxic.
- Do not apply very cold water or ice, because they cause vasoconstriction and chills, making it difficult to lower the temperature.
- Avoid sudden temperature changes; the drop should be gradual.
4. Nutrition and rest
When a child has a fever, it is normal that eat lessThere's no need to force-feed; the priority is that drink fluidsLight and easily digestible meals can be offered if desired (smooth purees, fruits, yogurt, etc.).
Facilitate the rest It's essential. Let the child sleep longer than usual if needed and adapt the day's activities: quiet games, reading, drawing... Listening to the body helps with a faster recovery.
5. Antipyretic medications
If the child you are uncomfortable and / or the fever is highYou can give them some pain reliever and fever reducer. The most commonly used are... paracetamol or ibuprofen (the latter is only indicated) in children older than 6 months).
Important recommendations:
- Use only the recommended doses by the pediatrician, calculated according to the child's weight.
- Always respect the intervals between shotseven if the fever reappears sooner.
- Administer medications whenever possible orallyThe rectal route is reserved for cases in which the child cannot tolerate anything by mouth.
- It is not advisable to alternate both medications simultaneously to lower the fever. This habit increases the risk of confusion and more side effects appear.
Remember that lowering the fever it is not essential If the child is well. The main goal of treatment is improve comfort, not normalizing the thermometer at all costs.
When should I see the pediatrician?
There are situations in which, even if the child doesn't seem seriously ill, it's advisable to have them evaluated by their pediatrician within the next few hours. You should consult a doctor when:
- The fever lasts more than 48-72 hours without a clear focus or without improvement.
- If you have 3 to 6 months and its temperature exceeds 39 ºC or if it has 40 ºC with any age.
- The child is very irritable or sleepy, more than usual.
- If you are down to despite the fever going downor has very intense, inconsolable, or very irritable crying.
- The boy has poor overall appearance or shortness of breath (breathing very fast, ribs showing, moaning, or skin sinking in between the ribs or on the neck).
- When you reject the food or fluids persistently.
- If you get a Rash on the skinred or purple spots, or bruises that were not there before.
- If the child has less than 3 months oldIn any case, if you have a fever, you should be evaluated by a healthcare professional.
It is also advisable to check if the child suffers from any serious chronic illness or has problems with the defenses (immunodeficiencies, immunosuppressive treatments…), since even a seemingly mild infection can become more complicated.
And whenever your common sense suggests it. Keep in mind that if you can't find an explanation for your child's fever, it's best to consult their pediatrician so they can assess the situation and advise you.
Do I have to take you to the ER?
Of course...provided any of the following warning symptoms appear, which may indicate that the infection is more serious or needs immediate attention:
- Temperature above 40ºC maintained that does not yield to the usual measures.
- High fever when our children have any serious chronic disease (heart disease, severe lung disease, major neurological disease, cancer, serious immune system problems…).
- Stiff neckDifficulty or pain when flexing the neck. If you are unsure, ask your child to look at your navelWhen someone can't do that, we say they have neck stiffness. Sometimes fever causes a false nuchal rigidityBut if the fever has already subsided and the child is unable to look at his navel You should go to the emergency room..
- Wine-red or purple skin spots that They do not disappear when the skin is stretched or by pressing with a glass.
- Has been for the first time a seizure associated with fever, or presents any episode of loss of consciousness.
- He complains about very intense headache accompanied by repeated vomiting or extreme sensitivity to light.
- Breathe with significant difficultywith strange noises, their ribs or abdomen sink in when breathing, or a bluish color is noticeable on their lips or face.
- Presents persistent vomiting or diarrhea that does not improve and can quickly lead to dehydration.
Although sometimes the decision to go to the emergency room is quite difficult, it is always better “prevention is better than cure”If in doubt, especially with young children, it is best to have a professional assess the child and confirm that the situation is calm.
Having clear information about What is a fever, how to measure it correctly, and what to do in each situation This allows you to face these episodes with much more calm. Observing the child's general condition, ensuring their hydration and comfort, using fever reducers responsibly, and knowing when to consult a pediatrician or go to the emergency room are key to managing fever in children safely and confidently.