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Health

Flu symptoms: what do you need to know about it?

, medical expert
Last reviewed: 04.07.2025
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Flu symptoms are not always the same. Of course: more than 200 viruses and bacteria that infect humans with this disease mutate into the most bizarre compositions. It is not surprising that different people feel differently. What do you need to know about flu symptoms?

What do we know about flu?

Everyone has suffered from it, so everyone is familiar with the feeling of headache, fever, body aches that the flu rewards us with. It is worth knowing about this disease that it is a difficult to bear viral disease that attacks both children and adults at any age.

For the flu, whatever it is, a general toxic damage to the body is characteristic, because of which, in fact, we experience weakness, increased fatigue and aching joints. In addition to this, there is also a cough due to damage to the bronchi, a stuffy nose and a runny nose, which doctors call rhinitis. But it is advisable to know the symptoms of the flu in more detail in order to see a doctor in time and not confuse the flu with a trivial cold.

Flu symptoms in detail

Flu usually starts suddenly. In fact, it is not so sudden, because the incubation period of this disease is from one to five days. That is, the flu virus hides in our body, doing its dirty work, and just one fine day knocks a person off his feet. Doctors call this acute clinical manifestations. How hard a person will tolerate the flu depends on his age, immunity, diseases that he suffered before. And also on whether the body is familiar with this particular type of virus. If so, the disease will be tolerated less hard and will pass faster.

Forms of flu severity and their characteristic symptoms

The course of the disease and how it is tolerated depends on what form of flu a person has: mild, severe, moderate or hypertoxic (there are four in total). Each form of flu has its own symptoms.

Mild form of flu

Symptoms of this form of flu are characterized by a high, but not too high, temperature of up to 38 degrees, fatigue, but not excessive, nasal congestion, and hyperemia (reddening of the skin).

Moderate flu

It is characterized by a fairly high temperature - above 39 degrees - headache, nasal congestion and body aches. This may be accompanied by heavy sweating, joint and muscle pain, weakness and sometimes nausea.

In moderate cases of influenza, a person may have catarrhal symptoms. These include hoarseness and sore throat due to damage to the larynx and trachea, coughing that causes pain, chest pain, severe nasal congestion and blocked respiratory passages, dry nasal mucosa, dryness and sore throat. This form of influenza is also characterized by catarrhal symptoms. These include abdominal pain, sometimes diarrhea (although this is rare and can be a manifestation of other diseases).

Severe form of flu

In this form, a person's temperature goes off the scale - above 40 degrees. This is especially dangerous for people with cardiovascular diseases, and a fatal outcome is possible. In a severe form of the disease, a person exhibits the same flu symptoms that are characteristic of the moderate form, but hallucinations, convulsions, vomiting, nosebleeds, and high blood pressure are added.

Hypertoxic form of influenza

The fourth form of influenza, the hypertoxic form, is characterized by damage to the nervous system and all the other symptoms characteristic of a severe form of influenza. Most often, the disease ends in death.

It is worth knowing that with a mild and moderate form of flu, if a person has been in bed and has not been overcooled, the disease can last from 5 to 10 days. But a person can experience weakness and headache for another three weeks after recovery. He may also have insomnia, increased irritability and fatigue.

Flu and flu symptoms are no joke, with this disease you should definitely see a doctor and stay in bed. Then, with a high probability, the flu will pass without complications.

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