Fever is the body's reaction not only to bacteria, viruses or fungi, but also to allergens, foreign bodies or chemicals, for example. It should also be remembered that a fever is a body temperature above 38 ° C, previously we are talking about a low-grade fever. The fever can be low, moderate, severe, and high - how are they different? Check when a fever strengthens the body's defenses? When does high fever become serious and how to lower it?

Fever(Latinfebris ) is an increase in body temperature above the physiological norm, which is the body's primary response to attacking bacteria, viruses or fungi, but also, for example, against allergens, foreign bodies or chemicals. A fever is a symptom of an illness, not a disease in itself. At higher temperatures, it is more difficult for microorganisms to reproduce.

Although most of us commonly use the word "fever" when the body temperature exceeds 36.6 ° C, officially it can be said that someone has a fever when their body temperature reaches or exceeds 38 ° C - below at this temperature, we are dealing with a low-grade fever. Depending on how high the fever is, doctors use the terms:

  • slight (low) fever- 38.0-38.5 ° C
  • moderate fever- 38.5-39.5 ° C
  • severe fever- 39.5-40.5 ° C
  • high fever- 40.5-41.0 ° C
  • excessive feverthat ishyperpyrexia->41 ° C

Why do we need a fever?

A rise in temperature above normal usually tells you that something is wrong with your body. This "warning system" is located in the hypothalamus (part of the brain). This is where the thermoregulation center is located, which maintains the balance between heat production (mainly by the muscles and the liver) and its loss (e.g. through the skin).

When, for example, viruses or bacteria invade the body, the cells of the immune system begin to produce special proteins that alert the thermoregulatory center to increase the body temperature.

What for? Because a fever is not only a warning about a threat, but above all a defensive reaction of the body. At a temperature of just above 38 ° C, immune proteins are most active, so they effectively protect against viruses and bacteria. When the body temperature is increased, the concentration of iron and zinc in the plasma decreases, which inhibits the growth of microorganisms.pathogenic.

In addition, the fever accelerates the metabolism, which activates a kind of "turbocharging" for the immune system, and cleansing the body of toxins faster.

Fever: symptoms

Fever usually accompanies:

  • heart rate increase of 4.4 beats / minute for each 1 ° C increase in body temperature
  • loss of appetite
  • headaches due to dilation of the meninges
  • if fever continues - loss of fat and muscle mass
  • the accelerated rise in body temperature is accompanied by chills, and its sudden drop - profuse sweating
  • over 40.5 ° C patients lose their orientation and start delirious, above 43.5 ° C - they go into a coma

Fever: types

In common parlance, fever and hyperthermia are used interchangeably, but the meanings of these words must be distinguished. Hyperthermia (an increase in body temperature above the norm may result from excessive overheating of the body) is not dependent on the thermoregulation center. Sometimes the fever is not continuous (the temperature is constantly high and does not drop to normal), but has an unusual course:

  • intermittent fever( febris intermittens ) - it increases, it normalizes
  • recurrent fever( febris recurrens ) - periods of increased body temperature, separated by fever-free periods, repeated with more or less regularity every few , several days
  • irregular fever( febris irregularis ) - no characteristic pattern can be distinguished in the elevated temperature curve: the fever varies from hour to hour hour, overnight
  • fleeting fever( febris ephemerea ) - lasting up to 1 day
  • slowing fever( febris remittens )-with daily differences not exceeding 1 , 5 ° C
  • digestive fever(hectic - febris hectica) - the temperature fluctuates by as much as 5 per day, this type of fever means significant impairment of the thermoregulation center

In elderly people, the feverish reaction is usually weakened. Young children and some patients (e.g. alcoholics) may react to severe infections with a drop in body temperature, i.e. hypothermia.

Fever: causes

Fever is a symptom that accompanies many diseases, ranging from banal colds to cancer, it occurs wherever there is inflammation. They suffer from it, among others.affected patients:

  • respiratory tract infections, both bacterial and viral:
    • colds
    • flu
    • bronchitis
    • pharyngitis
    • angina
    • otitis
    • sinusitis and much more
  • urinary tract infections (e.g. cystitis)
  • infectious diseases (e.g. three-day fever, chicken pox, mumps, rubella, measles, shingles)
  • diarrhea caused by e.g. rotaviruses, noroviruses, adenoviruses, but also bacteria, e.g.salmolella ,E. coli
  • hyperthyroidism
  • phlebitis
  • heart attack
  • stroke
  • cancers and their treatment (e.g. chemotherapy)
  • autoimmune diseases (systemic lupus, arthritis)
  • extensive injuries (e.g. burns, fractures, skull injuries or internal injuries)
  • diseases of the nervous system (encephalitis, meningitis, acute transverse myelitis)
  • bacteraemia, sepsis

There are alsofever of unknown origin(fever of unknown origin - FUO or pyrexia of unknown origin - PUO) is defined as a fever above 38.3 ° C, repeated many times, without recognizing the cause for at least 3 weeks (including a week of research in a hospital setting).

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According to an expertKrystyna Knypl, MD, PhD, internist

What is cerebral fever?I would like to know what is cerebral fever? What are its symptoms, how long does it last, how to get rid of it? Is it something dangerous? The patient who has been "diagnosed" with this fever has not been bitten by anything and is an elderly person.

Dr. Krystyna Knypl, internist: Cerebral fever occurs as a result of damage to the thermoregulation center in the brain, which acts as a kind of thermostat in our body. Usually in such cases the body temperature is 40-41 ° Celsius. The management depends on the underlying disease in the course of which the function of the thermoregulation center is disturbed.

Fever - how to lower the high temperature?

Supporters of natural methods have various possibilities. Herbal teas with a diaphoretic effect (from linden flowers, raspberries, flowers or elderberries) are very effective, because when the skin sweats, it gives off heat to the outside. In case of a fever, you need to drink a lot (liquids should be at room temperature) - even up to a few liters a day, because the body quickly loses water to evaporation and sweating.

You can cool your body down in a few minutes' bath - water in a bathtubshould be 1 degree lower than body temperature. You can also apply cold compresses in the places of the course of large blood vessels - groin, neck, poplite pits. Cool compresses on the forehead, neck and back of the head will help protect the brain from overheating. A naked child can also be wrapped in a wet, but not cold, sheet, without any additional cover (it is about steaming).

Pharmacological agents and preparations with paracetamol, ibuprofen, and acetylsalicylic acid are usually the fastest and most effective in dealing with fever. Overdosing them can be dangerous, so follow the manufacturer's recommendations. Take the dose recommended in this leaflet and check the temperature after an hour to see if it works. After a further two hours, measure the temperature again and check whether the downward trend continues. If not, take a second dose of antipyretic medication.

Be careful with medications containing acetylsalicylic acid (Latinacidum acetylsalicylicum , colloquially aspirin). In the case of flu and chickenpox, they can cause life-threatening complications in the form of Reye's syndrome (it causes unfavorable changes mainly in the brain and liver).

Important

Fever - when to see the doctor?

In case of a fever, we don't have to run to the doctor right away. But you have to go to him when:

  • the temperature exceeds 40 ° C
  • lasts more than 3 days
  • has a tendency to relapse
  • fever is accompanied by pain in the chest, abdomen and lower abdomen, you feel pain when urinating, you have nausea, vomiting or severe diarrhea, or when the increase in body temperature is accompanied by photophobia, numbness in the neck
  • a person over 70 or a child with previous febrile seizures has a fever
  • in children - if the fever appears in the first months of life, when the temperature reaches 39 ° C or is accompanied by convulsions

When the temperature drops below normal

This happens in hypothyroidism (this disease is manifested by a reduced level of metabolism) or after prolonged stay in cold water (hypothermia). Temperature below 36 ° C also happens in the case of the weakening of the body after a serious illness, after experiencing strong, long-term stress. Too low body temperature is usually accompanied by a feeling of weakness, depressed mood, and a tendency to faint. These are not life-threatening symptoms, but they are unpleasant. It helps then to drink more warm fluids - in this way we indirectly replenish the blood volume (weakness is accompanied by low blood pressure). It is also advisabletaking multivitamin supplements. When a fainting occurs, the casu alty is placed with the legs raised higher than the head and a supply of fresh air is provided. After fully regaining consciousness, we give fluids.

Worth knowing

Although each of us knows that the body temperature of a he althy person is 36.6 ° C, measuring it, we rarely can boast of this perfect result.

This is an average value, because the temperature fluctuates physiologically during the day - the lowest is in the early morning, when metabolic processes are slowest (approx. 36 ° C), and the highest in the late afternoon, when the body is working at full capacity ( approx. 37.2 ° C). It also depends on where it is measured - in the morning the armpit or mouth is around 36 ° C, and in the rectum it is half a degree higher.

The body temperature also depends on the individual properties of the organism (age, intensity of metabolic processes), previously taken antipyretic drugs or corticosteroids. So what is the correct body temperature? It is a temperature in the range of 36-37 ° C (measured in the armpit).

Category:

Immune system