How to recognize when the immune system is mobilised

Have you ever wondered how you can tell that your immune system is at work?
Here are some key signs.

When the body detects a threat — such as a virus or bacteria — the immune system quickly mobilises its defences. You can feel them working by:

• Fever and warmth – an increase in body temperature makes it harder for microbes to survive and signals active defence.
• Fatigue – energy is redirected from daily activities to the “battlefield”, so you may feel unusually tired.
• Swelling or redness – local signs of inflammation show that immune cells have gathered to fight at the site of infection.
• Mucus and cough – natural mechanisms to expel intruders from airways.

All these reactions, though sometimes uncomfortable, are signs that the immune system is alert, active, and working hard to protect you.

⚠️ But note: If the above symptoms are very severe, prolonged, or worrying, always consult a doctor. Do not rely on internet information!