Causes of temperature increase to 38-39.5 in adults and children
Last reviewed: 23.04.2024
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In our body there is an interesting system that maintains the constancy of the internal environment of a person by controlling the temperature. But if we get sick, it sometimes fails and the thermometer starts scaring us when the temperature of 38-38.5-39-39.5 degrees rises progressively on it, and sometimes higher. The first thought that comes to mind is the question of what fever and heat can be associated with. And the second - is it necessary to shoot down such a high temperature, which is in the range of 38-39.5 degrees? We will try to understand these questions.
Causes of temperature increase in adults
The temperature increase is not a serious reason for panic, as long as it does not go beyond the mark of 39.5-40 degrees. But this is already an alarming signal to think about the state of one's health, because, from scratch, such failures in thermoregulation usually do not occur. And even if there are no other symptoms of the disease besides the temperature, you should not especially relax, because fever, if it is not caused by overheating, in most cases is a manifestation of the inflammatory process in the body.
If the body temperature rises to the levels of 38-39.5 degrees in an adult, the following pathologies can be suspected:
- Viral and bacterial respiratory infections.
- A sharp increase in the thermometer, accompanied by fever most often, most of all debut viral infections. The most popular diseases of this nature are ARVI and flu, which rarely occur without a rise in temperature. But at the same time, the heat does not last long and indicates that the body is actively involved in the fight against pathogens.
- Somewhat later, the temperature appears with bacterial infections. And since there is not only the activation of protective forces and the body’s desire to create conditions for bacteria that are not suitable for their life and reproduction, but also intoxication with the products of vital activity of the pathogens, the thermometer may even reach 40-41 degrees in some cases. And the harder the infection, the higher the temperature.
Diseases such as pharyngitis (inflammation of the tissues of the pharynx), laryngitis (inflammation in the larynx), tonsillitis (inflammation of the tonsils or tonsillitis) in an acute form almost always occur with an increase in temperature regardless of who caused the disease: bacteria or viruses.
Temperatures above 38 degrees can also rise in acute bacterial infections of the nose, typical of sinusitis: sinusitis, sinusitis, ethmoiditis, sphenoiditis. Fever is more characteristic of purulent pathologies occurring in the acute form, while the catarrhal forms and the chronic course of the disease are rarely characterized by an increase in thermometer indicators above 37.5-38 degrees.
Acute diseases of the lower respiratory tract can also occur with a high temperature: bronchitis, tracheitis, pneumonia, as well as a purulent process in the middle ear (otitis). The causative agents of the above diseases are rarely viruses, most often it is a bacterial infection. And if Staphylococcus aureus has a hand on the inflammation (representative of conditionally pathogenic microflora, which is found on the human body), then the purulent process and temperature are provided to the person.
When a fungal infection, on the contrary, the temperature adheres to subfebrile values.
- Inflammation of the internal tissues of the brain or its membranes.
Diseases such as meningitis and encephalitis can begin with a rise in temperature of up to 38-39 degrees. This is the most common febrile form of inflammatory pathologies of the brain caused by viruses, bacteria, protozoa.
In secondary forms of disease, an increase in temperature may be observed at different stages of the development of the disease.
- Acute infectious-inflammatory processes in the urogenital system.
It is mainly about such popular urinary tract diseases as cystitis (inflammation of the bladder), pyelonephalitis and glomerulonephritis (inflammation of the pelvis, cups, parenchyma or kidney glomeruli) that can be diagnosed in both men and women.
But an increase in temperature can also be observed in severe inflammation of the urethra (most often, an increase in the thermometer's values to 38-39 degrees is associated with generalization of the infection and its spread to the tissue of the posterior wall of the urethra during gonorrheal urethritis). Uncomplicated urethritis rarely causes fever, as are inflammatory diseases of the female genital tract.
With regard to sexually transmitted infections, with a temperature rise above 38 degrees can occur:
- secondary syphilis caused by treponema pallidum,
- endometritis (inflammation of the inner layer of the uterus) and adnexitis (inflammation of the appendages and fallopian tubes) in women, as well as prostatitis (inflammation of the prostate tissue) in men caused by gonococci,
- epididymitis and orchitis (inflammation of the appendages and testicles) in men caused by trichomonas infection.
True, fever usually occurs on the background of a complicated course of the above pathologies and is accompanied by other severe symptoms from various organs (severe weakness, significant loss of appetite, muscle pain, migraines, etc.).
- Diseases of the digestive tract and intestinal infections.
It must be said that inflammatory diseases such as gastritis, gastric and duodenal ulcers, duodenitis, colitis and enterocolitis rarely cause a rise in temperature to 37.5-38 degrees. Even if they are acute. Although severe acute pancreatitis (inflammation of the pancreas) does not exclude a rise in temperature to 38-39 degrees, which is considered a very alarming symptom, and acute cholecystitis and cholangitis (inflammation of the gallbladder and its ducts) may be accompanied by even stronger fever (up to 40 degrees ).
A temperature rise to 38-39 degrees is possible with perforation of gastric ulcers and gastrointestinal bleeding, while hyperthermia is usually observed only some time after the process starts, and this is a reason to sound the alarm.
A temperature above 38 degrees accompanied by symptoms of acute appendicitis most often indicates that the inflamed organ has ruptured, and its contents have fallen into the abdominal cavity, causing an life-threatening inflammatory process (peritonitis). In this case, the temperature may rise to 40-41 degrees.
In intestinal infections that occur with severe intoxication of the body and malfunction of various organs, including the hypothalamus, which is responsible for thermoregulation, the temperature rises almost always, while its range may vary between 37-40 degrees. The causative agents of such infections as dysentery, salmonellosis, cholera, typhoid fever, infectious hepatitis and others can be bacteria, viruses or parasites. In this case, diseases very rarely occur in a latent form and are characterized by severe symptoms of the gastrointestinal tract.
- Myocardial infarction.
In this case, the temperature rises already in the post-infarction period 2-3 days after damage to the tissues of the heart. Usually it does not exceed 38 degrees, but its increase over this indicator may indicate serious complications, one of which is pneumonia.
- Blood diseases.
Febrile temperature is more characteristic of leukemia (leukemia). In the acute form of pathology, thermometer indicators reach 40 degrees, while no drugs help to normalize the temperature.
- Diseases of the bones and joints.
Often, these diseases do not cause a strong increase in temperature, as they tend to occur in a chronic form. But sometimes in the acute stage of arthritis (inflammation of the joints, especially if we are talking about the rheumatoid form of the disease), bursitis (inflammation of the periarticular bag), osteomyelitis (inflammation of the bone tissue), a temperature of 38-38.5-39-39, 5 and even 40 degrees. And we are not talking about a local temperature increase, but about a feverish state.
- Oncological diseases.
It must be said that the temperature, like pain, in malignant diseases rises already in the later stages of the development of pathology as a result of poisoning of the body with the products of tumor breakdown. Indicators of a thermometer in this case rarely go beyond the mark of 38.5 degrees.
- Vascular disease.
The temperature usually increases with inflammatory diseases. For example, with thrombophlebitis, it is often kept within 37.5-38 degrees. But acute thrombophlebitis of deep veins already in the first days of the disease is characterized by hyperthermia with a temperature range of 39-40 degrees.
- Diseases of the hypothalamus.
The destruction of the cells of this part of the brain responsible for the thermoregulation of the body and many other processes in the body is called the hypothalamic syndrome. Body temperature can vary between 38-39 degrees.
- Diseases of the thyroid gland: hyperthyroidism.
It must be said that an increased body temperature in patients is observed only against the background of an increased thyroid hormone production by the thyroid gland, while it rarely rises above 37.2-37.5. But an excess of hormones causes intoxication of the body (it’s not for nothing that the disease is called thyrotoxicosis) and at some point a thyrotoxic crisis may occur. And already it is characterized by an increase in temperature to 39-40 degrees.
- Neuropsychiatric disorders.
Temperature fluctuations in the range of 37.5-39.5 degrees (sometimes the thermometer can reach 40-41 degrees) are observed in the malignant neuroleptic syndrome, which develops against the background of mental diseases that require correction of behavior through potent drugs from the neuroleptic discharge.
The rise in temperature to 38-40 degrees is one of the main somatic symptoms of a very severe form of schizophrenia - febrile, sometimes referred to as fatal or lethal catatonia.
- Mastitis and lactose.
In women during breastfeeding, there are problems that can cause a temperature rise above 38-39 degrees. It is an inflammation of the mammary gland caused by hypothermia or milk stagnation in the breast. Sometimes mastitis can develop outside breastfeeding, which does not exclude a rise in temperature.
As you can see, a strong increase in temperature in an adult is an alarming symptom, because it can signal serious health problems. The most common cause of hyperthermia are viral and bacterial infections, or rather the inflammation and intoxication caused by them. An infection can be hidden in various organs and systems of a person, and depending on this, other symptoms of diseases arise, in addition to high fever, which in itself makes it impossible to make a diagnosis.
One of the risk factors for severely diagnosed infections is a trip to exotic countries, from which you can bring rare but very dangerous diseases in our area that occur with fever and fever.
But colds infectious diseases are most easily picked up by a non-tempered person, as well as those whose body is weakened by chronic diseases. As for the pathways of pathogen penetration into the body, the oral route is considered to be the most frequent (through unwashed hands and low-quality food, as well as during inhalation through the mouth).
Non-pathological risk factors for a high temperature increase include a long stay under the open sun on the days of its increased activity. In this case, an overheating of the body can be obtained by a child, an adult, and an elderly person. Less often, temperatures above 38 degrees can rise against the background of severe stress experienced.
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High fever in children
The child’s immune system is formed within 3 years after birth, so it is not surprising that babies usually get sick more often and more severely. Newborn babies plus, besides, the mechanism of thermoregulation is not sufficiently formed, so their body temperature can often change, although the indicator is slightly above 38 degrees, not related to the disease, it can only be in the first days after birth.
Heat transfer in the child's body stabilizes only by 7-8 years. It is from this age that stabilization of perspiration is noted, contributing to the cooling of the body.
The children of the first years of life overheat very quickly, so even increased physical activity in dry hot weather or improper selection of clothes can be the reason for the temperature to rise to 38-38.5 degrees. By the way, both points can be considered risk factors for colds, which occur with increasing temperature. After all, from overheating to hypothermia is only one step: it is only for the baby to sit down to rest in a cool room or to undress after he has become hot, and he has sweated, the body begins to cool sharply. The temperature difference, and now the baby squishes his nose, refuses food because of a sore throat, begins to cough up.
Temperature 38-39.5 in a child, as in an adult, is not considered a variant of the norm and in most cases indicates a cold. After all, hypothermia is a strong blow to a weak immunity from birth, which is unable to resist infection.
Most often we are talking about bacterial and viral ENT infections that cause inflammation in the throat, nasal passages and sinuses, organs of hearing. Angina, pharyngitis, otitis, acute respiratory infections, SARS are considered the most frequent diagnoses in young children. At the same time, the lack of treatment or its inefficiency very quickly leads to the transition of the same pharyngitis to laryngitis, bronchitis, tracheitis, pneumonia, which in children proceed very hard with a temperature rise up to 40 degrees.
In principle, an increase in temperature in response to the invasion of pathogens is a normal protective reaction of the organism, but due to the imperfection of the mechanism of thermoregulation, the increase in temperature indicators may be excessive, which becomes dangerous not only for pathogens, but also for the child himself.
With high fever, many viral infections characteristic of younger children can occur: measles, rubella, chicken pox, rotavirus infection, mumps (mumps), sudden exanthema. In this case, the disease does not have to be accompanied by symptoms of the respiratory system. So rotavirus infection and sudden rash, caused by herpes viruses 6 and 7 types, can debut diarrhea on the background of a sharp increase in temperature.
Herpes virus in babies can provoke the development of stomatitis, which is quite difficult. Fever in this case is considered to be quite a popular symptom against the background of worsening general well-being and a significant decrease in appetite, and sometimes even a complete refusal to eat.
As for bacterial infections, the corresponding pathology of the urinary system can be the reason for the increase in thermometer indicators in a child: cystitis, pyelonephritis, glomerulonephritis. Moreover, the latter disease differs in childhood by a very severe course with a rise in temperature of up to 40 degrees. Inflammatory pathologies of the urinary tract can be recognized by an increase in the frequency of urination, pain and cramps during them, causing the child to cry and act up.
To non-pathological reasons, in addition to overheating, which is able to raise the temperature of the child’s body to 38-38.5-39-39.5 degrees, teething can also be attributed. With a noticeable increase in temperature and great anxiety, the teeth are cut in children up to 2-2.5 years. At the same time, the child himself often cannot explain the cause of his anxiety and whims. Especially high temperatures are observed in babies up to a year.
Later, at the age of 6-8 years, hay of the primary teeth begins on permanent, which is infrequent, but can occur with temperature. True, to the level of 38-38.5 degrees, it rises extremely rarely.
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Basics of Symptom Self-Diagnosis
When the temperature rises, we do not always have a desire or have the opportunity to see a doctor. The easiest way is to bring the temperature down with a tablet and observe whether other symptoms of the disease appear, and they will definitely appear, because we create all the conditions for the multiplication of infection and the progression of pathology. But before you run for medications, you need to understand at least approximately what the fever is about and how dangerous this condition is. After all, the waiting position often only worsens the prognosis for recovery, and sometimes it becomes the cause of the lethal outcome.
The temperature of up to 38 degrees most people suffer well and may not even pay attention to it, unaware of the disease. This often happens if subfebrile fever is so far only the first sign of pathology. But the temperature of 38-38.5-39-39.5 degrees can no longer go unnoticed. The human condition in this case worsens even in the absence of other manifestations of the infection.
Temperature 38-39.5 without symptoms may be the first sign of a disease of the inflammatory plan, and the result of overheating of the body. In the second case, in addition to an increase in temperature, weakness, drowsiness, and apathy can be observed. The higher the degree of overheating, the harder the symptoms become. When the body temperature rises to 38-38.5 degrees, a person becomes thirsty, he becomes unbearably hot, and his pulse noticeably quickens even at rest.
With a further increase in body temperature, the skin of the victim turns red, sweating increases (as they say, sweat and hail), apathy gives way to agitation, but at the same time, the person is tormented by a severe headache and a feeling of squeezing of the head in the temples.
Extreme overheating is considered a heatstroke, in which the activity of the cardiovascular and nervous system is disrupted. Symptoms of heat stroke are fever of up to 39.5-40 degrees, nausea and vomiting, severe headaches, rapid pulse and heartbeat, arrhythmia, fainting, delirium, coma.
High temperature without symptoms should not be overlooked, because this is direct evidence that the body has begun an active struggle with an invisible enemy. The remaining symptoms of the disease may appear a little later, on the second or third day, if the rise in temperature did not lead to the elimination of pathogens.
For example, the first signs of osteomyelitis in the form of malaise, minor muscle and joint pain, a person may not even notice and suspect a certain disease in himself only when his temperature rises (with a local form of pathology up to 38 degrees, and with generalized disease — up to 39 degrees). 39.5). Severe pain, swelling of the affected area, aching bones, deterioration of well-being due to intoxication, neurological symptoms and malfunctioning of the kidneys are observed after the temperature rises.
But when inflammation of the joints may be the opposite, first articular pains appear, limiting the mobility of the joint, and then the temperature rises.
In the latent form, many infectious diseases can occur: meningitis, endocarditis, prostatitis, pyelonephritis and even pneumonia. Often patients are brought to the hospital by an ambulance with fever and fever, and an X-ray examination shows he has pneumonia, which the person did not even suspect. Temperatures of more than 39 degrees may for the time being be the only manifestation of such a dangerous pathology as sepsis.
High fever without any other symptoms can debut tuberculosis and tonsillitis, many viral infections. But with blood diseases and oncology, fever is already a late symptom, however, until it appears, a person may not have been aware of the disease for several months or even years.
It is easier to diagnose the disease if it has other symptoms besides heat. Thus, a temperature of 38-39, 5 and a sore throat are characteristic clinical picture of acute tonsillitis (angina), a runny nose in addition to the described symptoms is more characteristic of ARD, ARVI and flu, and cough - inflammatory diseases of the lower respiratory tract (bronchitis, tracheitis, pneumonia ). That is, these are all symptoms of respiratory infections.
In addition to high otitis, there will be severe pain in the affected ear, as well as headaches. The latter, by the way, often accompany viral infections along with increased eye sensitivity to light.
Diarrhea with colds rarely occurs when the infection penetrates the digestive tract. The exception is rotavirus infection, affecting mainly children. This disease, commonly called the intestinal flu, is characterized by a tandem of intestinal and respiratory symptoms (especially at the onset of the disease).
For rotavirus are characterized by: a sharp increase in temperature to 38-39, 5 degrees, vomiting, grayish-yellow liquid feces, which are combined with a cold, hyperemia of the throat tissues, pain when swallowing, i.e. Some combination of enteritis and sore throats. Light feces and dark urine generally resemble the symptoms of liver damage (hepatitis).
By itself, diarrhea most often indicates an upset stomach caused by the use of poor quality or inappropriate food, especially if it is not accompanied by respiratory symptoms. But if a person has diarrhea and a stomach ache, and the temperature is in the range of 38-39.5 degrees, most likely, this is not a simple poisoning, but an intestinal infection, for the treatment of which only gastric lavage and the intake of sorbents is not enough.
By the way, acute hepatitis and appendicitis can also be characterized by similar symptoms. In these cases, fever, pain in the right hypochondrium (with inflammation of the appendix, they can go lower), as well as diarrhea, nausea and vomiting, which do not bring relief to the patient, are also possible.
In any case, a combination of diarrhea, abdominal pain, nausea, vomiting, and fever is considered very dangerous. In this case, you need as soon as possible to go to the hospital, causing an ambulance.
Intestinal poisoning, hepatitis, appendicitis are dangerous in and of themselves. But similar symptoms also have a disease with a high risk of mortality - peritonitis (inflammation of the peritoneum), which is often diagnosed as a result of a rupture of the appendix and its contents entering the abdominal cavity. At the same time there are sharp abdominal pains, nausea and weakness, the temperature increases significantly.
The later symptoms of peritonitis are: severe paleness of the skin, sharp pain when pressing on the abdominal wall and tension of its muscles, vomiting, increased blood pressure, increased heart rate, hyperhidrosis, the appearance of symptoms of dehydration (thirst, reducing the amount of urine).
The combination of symptoms may look a bit strange: temperature 38-39.5 and cold feet. Despite the fact that it looks like an incident, in fact it is a very serious and quite logical situation. Recall that in the first stage of fever to reduce heat transfer, peripheral vessels narrow and the temperature of the skin decreases. Especially cold in this situation are limbs. And until the temperature stabilizes at any particular level, the skin and limbs will remain cold, regardless of the cause of the hyperthermia.
If the body becomes warmer, this indicates that there will be no further temperature increase. But cold hands and feet say the opposite. If the temperature exceeds 39.5 degrees, it is possible to talk about a potentially life-threatening condition - hyperthermic syndrome, accompanied by inhibition or, on the contrary, nervous system stimulation, skin cyanosis, impaired heart function (high blood pressure and heart rate due to increased stress on the organ).
Often at a temperature of 38-39, 5 we notice that the headache and aching body aches. Most often, this situation is observed in acute respiratory and intestinal infections, as well as inflammation of the membranes of the brain occurring with a sharp increase in temperature. The appearance of headaches in the temples, forehead and eyes caused by inflammation and intoxication of the body, does not cause questions. But why does muscle aches and body aches appear?
An increase in body temperature leads to the destruction of muscle fibers, as a result of which a special enzyme, creatine phosphokinase, is released. When this substance enters the bloodstream, pain occurs.
The aches in the body have the same reasons - changes in the characteristics of muscle fibers under the influence of high temperatures. Muscles become more dense and tense, not able to relax. This leads to a slowdown of blood circulation in the muscle and joint tissues, the development of oxygen deficiency in them, as a result of which the organs cannot perform their functions normally, and therefore signal disturbances with aches and pains.
Why does body temperature rise?
When a person is healthy, moderately active, not exposed to strong solar radiation and heat, his body temperature is maintained within 36.6-36.8 degrees. This temperature is considered normal, although in some people the rate may be slightly higher or lower.
Raising the temperature above 38 degrees is no longer the norm. Moreover, a further increase in thermometer indicators is fraught with the development of reactions dangerous to human health and life, since blood viscosity increases and the heart becomes harder to drive it through the vessels. That is why doctors recommend to beat the temperature, if its performance is above 38.2 -38.5 degrees, and with very poor health and earlier.
Despite the fact that many children tolerate fever, while remaining active and cheerful, it is believed that temperatures above 38 degrees are very dangerous for children due to the increased risk of developing febrile seizures. In this case, pediatricians differ slightly. Some insist that the temperature above 38 degrees in a child should be shot down in any case. Others believe that the vigorous condition of the baby at a temperature of 38-39 degrees does not require a medicinal correction that adversely affects the state of the liver. But given the fact that 39.5 degrees is already a critical indicator for everyone, it’s not worth bringing to it.
With the fact that you only need to bring down the temperature when we see high values on the thermometer, and our state of health deteriorates markedly, we have already figured out. Yes, the pathogenesis of fever in various diseases, i.e., remains unclear. Why does overheating occur at all if a person's thermoregulation system is so perfect?
Let's start with the fact that viruses and bacteria that enter the body and actively reproduce are not for nothing called pathogens. The cell wall of these microorganisms and their metabolic products contain special substances called pyrogens (which generate fire). These pyrogens are classified as exogenous substances, i.e. Coming from outside.
By themselves, exogenous pyrogens are not able to raise the temperature of the human body, but they stimulate the production of endogenous pyrogens in the lymphatic system (interleukins, interferons, cytokines, etc.). The active production of such substances is perceived by the hypothalamus in its own way. The normal body temperature now seems to him to be lowered and the regulating cent tends to raise it.
In order for the temperature to be constant heat production in the body must match the heat transfer. If this does not happen, the thermometer moves up or down. In the case when heat production prevails over heat emission, the temperature rises. In adults, this occurs due to a decrease in heat transfer, and in small children due to increased heat production.
The decrease in heat transfer occurs due to the narrowing of peripheral vessels and reducing sweating, provoked by the sympathetic nervous system. A spasm of small vessels reduces blood flow to the tissues of the body, the skin becomes pale, dry and cold, retaining heat inside the body. Reducing perspiration helps retain the heat that we lose by evaporating the fluid.
A decrease in skin temperature and the activation of sensitive thermoreceptors on it leads to the onset of chills. After all, the receptors give a signal about freezing to the brain, where a signal is formed for a certain behavior that contributes to the preservation of heat (a person tries to dress warmer, wrap up in a warm blanket and move less).
At the same time, the body's metabolism increases, which in turn increases the production of heat in the body. On the thermometer, this process is reflected in the form of a consistent increase in temperature to 38-38.5-39-39.5 degrees.
At some point, there is a balance in the production of heat in the body and heat transfer, which is identical to the normal one, but at the same time, the thermometer's performance will be noticeably above the norm. Now the temperature stops rising, but it can stick to high constant values for several hours, days, or even weeks.
The hypothalamus believes that he coped with his task and stabilized the temperature, which means that it is possible to give a signal for the reverse expansion of the vessels. This leads to the fact that the skin becomes the same shade and even become bright pink, when touched, there is a noticeable warmth, and there is no trace of the chill. If the temperature is kept within 38.5-39 degrees, the fever is called febrile, and the temperature rise to 41 degrees is called pyretic fever.
If no action is taken, the temperature will rise or stay high until such time as the amount of exogenous pyrogens in the body decreases or the synthesis of endogenous heat provocateurs decreases. The reduction of pyrogens in the body can be carried out under the action of medicinal antipyretics, or naturally, when the immune system suppresses the reproduction of pathogenic microorganisms and makes the microbes inactive.
Reducing the amount of pyrogens in the body is a signal to the hypothalamus to reduce the temperature, because the existing one begins to be perceived as increased. Expansion of blood vessels leads to the removal of excess heat. This also contributes to the activation of the process of sweating, evaporation of fluid from the skin and increased diuresis (production of urine). When heat transfer and heat recovery are balanced, we see normal readings on the thermometer.
As you can see, thermoregulation in the human body is a rather complicated process. Pyrogens in our body are special substances of protein nature, the production of which is controlled by the immune system. These substances provide protection of the body against alien invasion, because the inflammatory process and the temperature rise are a kind of defensive reaction, the purpose of which is to create conditions that are unsuitable for the life and reproduction of pathogens. Indeed, for most of them, the normal temperature of a human body is optimal.
Warming up the body leads:
- activation of metabolic processes, as a result of which toxic substances are more actively excreted from the body,
- increasing the production of antibodies and antiviral substances that provide local immunity (interferons),
- the destruction of pathogenic microorganisms that are dying from overheating, and the reduction of their livestock in the patient's body.
This again speaks in favor of the fact that it is not necessary to force down the temperature unless absolutely necessary and, thereby, prevent the body from fighting the infection. After all, if the temperature stabilizes, it will not be so easy to fight pathogens. Another thing is if the thermometer readings begin to approach critical, which will be more dangerous than the influence of viruses and bacteria.