Why does flu make you uncomfortable?

According to Business Insider, 5 to 10 percent of people in the United States are infected with influenza every year. An average of 200,000 of them will be hospitalized and about 50,000 will face the risk of death.

People from 65 years old are especially sensitive to the flu because their immune systems have weakened with age. In addition, older people often have a longer recovery time after getting out of the flu.

What exactly is happening in your body every time you get the flu?

We all know the symptoms of influenza include fever, cough, sore throat, muscle aches, headache and fatigue. But what exactly is happening in your body every time you get flu?

A scientist specializing in immunological studies at the University of Connecticut Medical School has focused on examining how flu affects the body and how our bodies fight viruses.

It is interesting to know that many of the body's defense mechanisms against viruses also cause symptoms that we can see every time we get the flu.

How does flu work in your body?

Influenza virus causes respiratory, nose, throat and lung infections.

Influenza virus causes respiratory, nose, throat and lung infections. Influenza viruses are usually inhaled or transmitted through the body (usually through the fingers) and then the mucous membranes of the mouth, nose or eyes. It then moves down the respiratory tract and binds to the lung epithelial cells through specific molecules on the cell surface.

This process will create some lung damage. Most of the symptoms of influenza are caused by the body's immune response to the virus.

The initial immune response is made by the body's innate immune system, such as macrophages and neutrophils. These cells have receptors that help identify the presence of the virus. They then emit an alarm by creating small hormone-like molecules called cytokines and chemokines .

Cytokines regulate other components of the immune system to fight invading viruses, while chemokines guide these components to the site of infection.

The initial immune response is carried out by the body's innate immune system.

One of the types of cells called into action is T lymphocytes , a type of white blood cells that fight infection. When specific T cells recognize flu virus proteins, they will begin to proliferate in lymph nodes around the lungs and throat. This causes swelling and pain in the throat.

After a few days, T cells move to the lungs and start killing infected cells. This process creates a lot of lung damage similar to bronchitis and the worst case scenario is that it makes patients feel short of breath.

In addition, the accumulation of mucus in the lungs (the result of an immune response) will cause a cough reaction (to clear the lungs). Usually, this injury is caused by T cells and it can be cured with people who are physically healthy. However, many cases of severe lung damage result in death.

The most important function of T cells is to remove flu virus from the lungs.

The most important function of T cells is to remove flu virus from the lungs . When this function is no longer strong - probably due to age or due to long-term use of immunosuppressive drugs - the purification of the virus from the lungs will no longer work.

This will lead to prolonged infection and more serious lung damage. It can lead to complications, including secondary pneumonia and this is often the cause of death for people with influenza.

Why do you have a headache when you have the flu?

Usually, flu viruses are almost exclusively present in the lungs. Some systemic symptoms of influenza are fever, headache, fatigue and muscle aches.

To combat effective flu, cytokines and chemokines are caused by innate immune cells in the lungs that enter the bloodstream and contribute to systemic symptoms as mentioned above. When this happens, a series of complex biological processes are carried out in the patient's body.

Some systemic symptoms of influenza are fever, headache, fatigue and muscle aches.

One of these is interleukin-1 , a type of cytokine inflammation, that is activated. Interleukin-1 is important for the development of T-cell response to fight the virus. In addition, Interleukin-1 also affects a part of the brain in the hypothalamus - this area of ​​the brain acts to regulate the body's temperature - causing fever and headaches.

"Tumor necrosis alpha factor" , another important cytokine against influenza infection is also triggered when the body has this disease. This cytokine has antiviral effect directly in the lungs but at the same time it also causes fever, appetite, fatigue and physical weakness when flu or other infections occur.

Why do your muscles also hurt?

The research of the scientist has found a different way of influencing the flu on our bodies.

Muscle pain is one of the most prominent symptoms when you have the flu. Research on animal models shows that influenza infection increases the expression of genes that weaken muscle weakness and reduces the function of muscle-producing genes in the musculoskeletal bones.

Functionally, influenza infection also affects normal walking of the legs. In young patients, these symptoms are transient and return to normal after the bacteria have been eliminated by the body.

Pain and muscle damage are an unexpected consequence when the body responds to an influenza virus immune response.

In contrast, these effects may exist significantly longer in the elderly. It is this that makes it difficult for older people to travel and fall easily from influenza. It can also lead to permanent disability that makes flu-affected feet lose flexibility after being cured, and in many cases use tools such as sticks to move.

Researchers think that pain and muscle damage are an unexpected consequence when the body responds to an influenza virus immune response. Scientists are trying to find ways to prevent this phenomenon in humans.

In short, when you feel uncomfortable with flu infection, rest assured that it is because your body is fighting hard. It is fighting the spread of viruses in your lungs and killing infected cells, of course you should also protect and support your body by avoiding the risk of flu, as well as going away. Medical examination and medication are indicated when ill.