BABY FEVER: A complete guide on the subject

Baby fever is one of the things that most make caregivers apprehensive and anxious. But concern is common and it is estimated that 20% to 30% of pediatric consultations have fever as their chief complaint.

According to the general clinic Marcia Bahia (CRM-MG 65221), fever is characterized by an axillary temperature above 37.2°C (35.8°C or 38°C, depending on the reference) and/or a rectal temperature greater than 38 °C The rectal measurement is the most accurate, as it has less influence from the external environment, but it is less practical and more invasive than the axillary measurement.

Fever quick guide

• Fever is a physiological mechanism to fight an infection. The child has a fever if the axillary temperature is greater than 37.2°C and the rectal temperature is greater than 38°C.
• The most common cause of fever is infection or inflammation. Most of the time it is fleeting. It tends to disappear on its own without needing to medicate.
• A child with a fever has a red face, a racing heart, rapid breathing, feels cold and is depressed. Other signs are irritability, lack of appetite and even crying.
• Rectal temperature measurement is the most effective, but it is less practical and can be more uncomfortable for the baby.
• Keep the child hydrated and at rest. Dress her in light clothes and keep the room ventilated. Give a warm bath and don’t use alcohol in the water, it can cause an allergy.
• Baby with fever can sleep. Children with fever are generally more unwell and sleepiness is common.
• Vaccinations can cause fever, but it is usually transient and can be treated with antipyretics for the child’s comfort.
• In general, the fever associated with tooth eruption is low and without complications.

Be aware of these emergency cases:

• Newborns up to 28 days old have a clear indication for hospitalization and immediate investigation of the cause of the fever.
• In any child, fever above 39.4°C or axillary temperature below 36°C. When the fever lasts longer than 3 days, it indicates a possible bacterial infectious agent.

See a doctor right away if your baby has other symptoms, such as a stiff neck, headache, severe sore throat and earache, unexplained rash, repeated vomiting, and diarrhea.

How to identify fever in babies

Fever can be defined as an axillary temperature above 37.2°C, or a rectal temperature above 38°C, and in the 3rd month of life the rectal measurement limit reaches 38.2°C. The best way to identify fever in babies is to measure the axillary or rectal temperature. However, other signs and symptoms can indicate the feverish state, such as irritability, unusual sleepiness and even crying. It is worth mentioning, however, that fever can appear as an isolated symptom, without necessarily leaving the child prostrate or irritated.

Rectal temperature is considered the most accurate to measure the body’s internal temperature. To measure, insert the thermometer into the rectum 5 cm from the baby for two minutes. The axillary temperature, which, although not as accurate as the rectal temperature, is quite satisfactory for clinical purposes. To measure, dry the armpit (if there is sweating), place the thermometer in the armpit and keep the arm firmly pressed to the chest for four minutes. On very hot days, take the reading immediately after removing the thermometer.

• +41:​ very high fever, usually associated with a picture of bacterial infection, roseola and other diseases that require closer care or even hospitalization of the child, due to the risk of dehydration and other complications.
• 39.5 – 41: fever.
• 37.5 – 39.5: ​hyperthermia (occurs in situations of excessive clothing, excess environmental heat and even in some specific cases of dehydration).
• 36 – 37.5: ​normal temperature.
• – 35: hypothermia

Causes

• Bacterial infectious cause: This is the most common cause of fever in babies. It is characterized by a fever of more than 39.4°C, especially accompanied by shivering cold.
• Viral infectious cause: This cause is more prevalent than bacterial. This type of fever can last up to 3 days without risk, as the adenovirus causes a slightly longer fever.
• Cause by rheumatologic disease: a rare cause.
• After taking the vaccine: this fever is fleeting because it is an immune response of the baby to the vaccine.
• Cause by skin injury: Babies can also develop fevers after a skin injury. This usually means there is an infection.

Fever is a symptom of an illness, not an illness itself. Children often have a fever when the immune system is fighting an infection.

Symptoms

The doctor Marcia Bahia says that the symptom that defines fever in babies is essentially the increase in temperature. Other signs and symptoms, however, may also be present and indicate the etiology of the fever and its consequences. Check it out below:

• Flu-like symptoms point to a possible airway infection.
• Diarrhea and vomiting indicate changes in the digestive tract.
• Neck stiffness present in some cases of meningitis.

Regarding the physiological changes in the body in response to fever, the baby may have tachypnea (increased breathing rate), tachycardia (increased heart rate) and signs of dehydration (very concentrated urine, low appetite, drowsiness, etc. ).

emergency cases

Some parents fear that fevers are dangerous, but they almost never are. Even so, there are cases where a fever can be a serious warning for the baby. Read the most common cases below:

• Fever in newborns (up to 28 days) – clear indication of hospitalization and immediate investigation of the cause of fever.
• Fever above 39.4°C or axillary temperature below 36°C.
• When the baby is toxemic, which means irritability alternating with drowsiness, apathy, lethargy, anorexia, moaning, low mood and weakness.
• When the fever lasts longer than 3 days, indicating a possible bacterial infectious agent.

It is imperative to seek medical assistance in any of these cases. Call a doctor or go to a hospital right away.

treatments

• Bathing: you can use warm immersion baths for 10 to 20 minutes, allowing the water to cool slowly, or gentle friction with a sponge moistened in warm water, making this friction on successive parts of the body for a total of 20 to 20 minutes. 30 minutes.
• Hydration: encourage the child to drink liquids, especially water.
• Removal of outerwear: wear light clothes, keep the environment ventilated. In the most pleasant hours of the day, the child can be outdoors, without direct exposure to the sun.

It is worth mentioning that cold water can cause chills and tremors that, in addition to discomfort, increase the temperature. Do not put a febrile child with a seizure in the bathtub or add alcohol to the water. Alcohol can be absorbed through the skin and cause systemic toxicity and therefore should never be used.

Common questions

Thinking about the most frequent doubts of mothers, fathers and caregivers regarding fever in babies, we interviewed the general clinic Marcia Bahia (CRM-MG 65221). Read the interview below:

1. How serious is a baby with a fever?

It is important to point out that the most common cause of fever in babies over 1 month is viral, the famous “virosis”, which is treated with measures and medicines that relieve symptoms, with the baby’s own body responsible for curing the disease. Babies with fever who present the warning signs described above should be referred to the medical service to evaluate the etiology of the fever and to perform the necessary complementary exams.

2. Can a baby with a fever sleep? Because?

He can! Children with fever are generally more unwell and sleepiness is common. Attention should be paid to the child’s temperature, but in non-serious cases, it is not always necessary to wake up the baby to give the antipyretic. The biggest fear in relation to sleep is about the febrile seizure, but, as mentioned above, it occurs in specific cases and, if a baby has already had a fever above 38.7°C and has not had a seizure, he will hardly present this change.

3. Can vaccines cause fever in babies? If yes, what should I do?

They can. Vaccines are small modified “pieces” of the virus or bacteria that generate an immune response in the baby and leave him able to fight these infections, if he has contact with them someday, but without generating the disease itself. In general, fever is transient and without complications and can be treated with antipyretics for the comfort of the child.

4. Can fever in babies indicate teething? If yes, what should I do?

He can. Studies show that there is an association between fever and teeth coming in, but in general this fever is low and better accurate by rectal temperature. Since fever is an isolated symptom, together with the birth of teeth, the baby can be treated normally with antipyretics, for the child’s comfort. In general, the fever associated with tooth eruption is low and without complications.

5. What to do if a 6 month old baby has a fever? And 1 year?

Children aged between 3 and 36 months have basically the same infectious etiologies as those with fever, with viral etiologies being the main ones. The initial step is always to try to confirm the fever by taking the child’s temperature and medicating him for comfort. It is also important to keep the child hydrated and offer foods that he/she accepts, but without forcing (lack of appetite is common). Fevers of viral origin last a maximum of 3 days and are almost always accompanied by a milder, without complications. When the fever exceeds 3 days and/or the child has warning signs, a more thorough investigation should be carried out. It is important that children are always evaluated by a doctor, to guarantee a mild condition, with assessment of vital signs and prediction of complications, or to identify a serious condition that requires more specific treatment. The management of fever in babies depends on several factors, such as the child’s exposure to someone who is sick, the baby’s vaccination status, the baby’s immune status, response to infection, ability to stay hydrated, among others. At this point, it is important that a child with a fever in this age group is always evaluated by a doctor.

6. Talk a little about the consequences of fever, such as dehydration and febrile seizures.

Dehydration often occurs in infants with fever and should be prevented with adequate oral hydration or even intravenous hydration when necessary.

Febrile seizure is a rare condition, usually associated with sudden onset fever with a temperature above 38.7ºC, in children aged 6 months to 3 years and genetically predisposed. It is known that febrile seizures do not carry a risk of brain damage in babies, despite being an undesirable event.

As we saw during the text, fever means that the immune system is working hard to fight an infection. Caregivers can comfort the baby and treat symptoms with the treatment suggestions we’ve given above. And most importantly, do not medicate without consulting a doctor. Look for his/her…