Along with coughing, fever is one of the more common signs of a corona infection. But at what body temperature do you have it anyway? And with which device and at which part of the body does the measurement deliver the most reliable result? FITBOOK has worked with the internist Dr. Spoken to Matthias Riedl.
If you want to measure your fever, you should know that the temperature is not the same everywhere on the body. Normally, the bodykerntemperature around 37 degrees Celsius. The further away from the core of the body, the cooler it gets. So the hands and feet can be at just 28 degrees, and feel with some “frostbite” known to be even colder. Therefore, it is of course important where to measure the body temperature, when this is done and what kind of thermometer is used. And FITBOOK also answers the question at what temperature one can speak of fever.
What is normal temperature and when does one have a fever?
If the thermometer shows a temperature between 36.5 and 37.4 degrees Celsius, this means normal temperature. Above it begins increased temperature. From regarding 38.1 degrees you have a slight fever. Medium fever describes the small range between regarding 38.6 and 39 degrees, everything following that is high fever – and can be life-threatening from 42 degrees at the latest. Here once more at a glance:
“But you can get typical fever symptoms much sooner. Many people physically notice a slight increase in body temperature at 37.5 degrees,” explains the internist dr medical Matthew Riedl in conversation with FITBOOK. Incidentally, the body temperature rises by up to one degree throughout the day. This means that the temperature is lower in the morning than in the evening. And if you are physically active, your body can warm up by up to two degrees.
All of this should be considered when measuring your own body temperature. And all the more important are accurate measurements.
The most accurate way to measure fever
If you really want to have an exact value, you should measure your body temperature rectally, ie in the buttocks. This method delivers “significant results” he writes Springer medicine publishing house and refers to a comparison of measurement methods by intensive care physicians at the Lougheed Center in Calgary, Canada.
The second best way to measure fever
According to experts, the most common method of measuring fever is the second most reliable. In the mouth, i.e. under the tongue, the measurement accuracy usually deviates by barely 0.5 degrees. Make sure, however, that you do not eat or drink anything ten minutes beforehand, as hot or cold food or drinks can falsify the result.
Which methods are inaccurate
The readings from the armpits are often imprecise – with a deviation of up to two degrees – and are therefore almost impossible to use for a medical classification. The same applies to forehead and ear thermometers.
What types of thermometers are there?
Glasthermometer
They still exist, but are rarely bought. Glass thermometers are sensitive and have relatively long measuring times. While alternatives can be read within a few seconds, glass thermometers take several minutes.
Digitale Thermometer
Most people probably have one at home by now – and it is also used by Dr. Riedl recommended. It is suitable for measurements under the tongue, in the armpits and in the anus.
Infrarotthermometer
Especially in times of Corona, they were often used in shops and medical practices: ear and forehead thermometers. They measure the temperature using infrared rays. This is quick and can be useful if e.g. B. the child is fidgeting and doesn’t want a thermometer in its mouth, let alone its bottom. However, the method is usually not very accurate, and experts tend to advise once morest it.
What’s the point of having a fever anyway?
“Fever serves to defend once morest infection or to worsen the living conditions of pathogens,” explains Dr. Riedl. If and when the temperature rises is controlled by the hypothalamus, a section of the midbrain that acts as the “command center” of the nervous system.
The exact process: When immune cells detect bacteria or viruses in the body, they send out messenger substances. These interact with other messenger substances until some of these so-called transmitters overcome the barrier between the bloodstream and the brain and sound the alarm in the hypothalamus.
Then what happens? The heating is turned up properly, explains Prof. Hanns-Christian Gunga from the Institute of Physiology at the Berlin Charité. This should serve the purpose of boiling off the pathogens.
Also interesting: Why do some people never get a fever?
Doctors advise reducing fever from 42 degrees at the latest
So fever is important. Therefore, a decision must be made on a case-by-case basis as to whether or not to intervene in the body’s natural defense reaction when the fever is trying to reduce.
like dr Riedl knows that younger people can usually withstand high temperatures relatively well. But: “If the impairment becomes too severe or there is a strain on the circulatory system, you should take measures.” The specialist points out that the pulse can rise significantly, “this can be critical for older people under certain circumstances”.
Prof. Gunga agrees. He would define a non-binding upper limit at 42. From a body temperature of around 42 degrees, not only bacteria die, but also proteins – i.e. vital building blocks of the cells. It is also problematic if the fever lasts for several days. “It takes an insane amount of energy to heat up the body like that,” he says. At some point the reserves will be exhausted.
Drugs or better with home remedies?
To lower the fever, you can try calf wraps first. “The extremities are the most insensitive to cold,” explains Prof. Gunga, which is why cool wraps are not uncomfortable there. If that doesn’t help, substances like ASA effectively interrupt the messenger chain. They inhibit prostaglandins, the last in the line of transmitters. The hypothalamus no longer receives a signal to heat up.
Also interesting: When you really should take antipyretic drugs
Because of Corona: Are prophylactic fever measurements useful?
There are many people who are currently taking their temperature every day in order to apparently examine themselves for a possible corona infection. “But that doesn’t make any sense,” says Dr. Riedl on FITBOOK. More reliable symptoms are a scratchy throat and severe cough, and these might also indicate other illnesses as well.
On the other hand, he thinks it makes sense to buy a clinical thermometer. “Many don’t even have one at home,” he knows from his practice. That should be changed if necessary – also independent of the corona virus.
