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What is the flu?
Medical expert of the article
Last reviewed: 07.07.2025
Influenza is one of the most common colds caused by viruses.
There are many viruses that cause flu, so this disease is divided into types: stomach flu, swine flu, bird flu, intestinal flu, and so on. More than 200 bacteria and viruses attack our body, causing flu symptoms. Therefore, it is easy to confuse it with other diseases, such as acute respiratory viral infections. What do we need to know about a disease such as flu?
What is flu?
Influenza is an acute respiratory disease caused by viruses, the symptoms of which appear after a 1-2 day incubation period. When a person has the flu, the following symptoms appear:
- Inflammation of the nasal mucosa - that is, rhinitis
- Inflammation of the larynx - that is, laryngitis
- Inflammation of the nasal sinuses - that is, sinusitis or maxillary sinusitis
- Cough - dry or wet - often occurs with bronchitis
- Respiratory disorders - croup
- High temperature and headache (although there may be no fever)
Flu: risk groups
Influenza most often affects the following groups of people:
- Women during pregnancy
- Children with weakened immune systems
- People after 46
- Social service workers
Flu is a very serious disease. It is only important to pay attention to it in time.
Why do doctors consider flu dangerous?
Flu not only prevents a person from living fully, perceiving reality, studying, and working. Flu is also dangerous because it is caused by a virus that constantly releases toxins into a person's blood. This is why, after you have had the flu, you may experience complications such as hearing loss, kidney and liver disease, and weakened function of all organs.
Flu leaves behind consequences: a person may experience muscle pain, aching bones, rapid fatigue, hypersensitivity of the skin, and sometimes even vomiting.
Flu is dangerous because it can lead to very difficult to bear toxicosis, damage to blood vessels, and internal bleeding, which can affect vital organs. In addition to all the other troubles, flu leads to heart rhythm disturbances, abnormal functioning of the heart muscle, and pneumonia.
Therefore, if you suspect you have the flu, you should definitely consult a doctor.
Influenza significantly weakens the immune system. This leads to bacteria starting to destroy the tissues of the upper and lower respiratory tract, causing pneumonia.