This Is How the Seasonal Flu Affects Your Body

how the seasonal flu affects your body

We all know the most common symptoms of the seasonal flu – coughing, fever, headaches, muscle pain, fatigue, and many more. But why do all these things happen to our body while it’s fighting off the infection?

In this article, we’ll try to explain how the seasonal flu affects your body.

The Immune System

Influenza is a disease of the respiratory system. And, while some injury to our lungs does happen during the infection, most flu symptoms are caused by our own immune system trying to fight the invader. Small molecules called cytokines play a vital role in this process, organizing other important components of the immune system like white blood cells.


One component that cytokines call into action is a type of white blood cells called T-lymphocytes. When these white blood cells enter the lungs, they start to fight the virus-infected cells which causes a lot of damage to the lungs. It also creates a lot of mucous in our lungs, which induces a familiar reflex – coughing. We use coughing to clear our airways.


The cytokines are also the reason why our head sometimes hurts. A specific type of cytokines called interleukin-1 is responsible for producing the T cells that kill the virus. However, this cytokine affects the part of our brain in charge of body temperature, which results in a headache and fever.

The Bottom Line

That’s how the seasonal flu affects your body. So, if you feel like you can barely walk and your head is about to pop, rest assured that’s just a sign of your body working at full capacity to fight off the virus and kill infected cells.