Why does my skin give off a glow and clear complexion when I'm sick?

I don%26#039;t get sick that often but when I do, like now im pretty sick (flu?), my skin just is more radiant and glowing and starts clearing up rapidly and I%26#039;ll walk down stairs and my parents are like why are you wearing makeup? And I have to explain that I didn%26#039;t. Its not like i wear alot of makeup I just find it so weird that it does this. Is there some scientific reason for this or just my genetics or skin type?|||First of all the glow is from the paleness, it makes your skin look like porcelain, your skin clears up, because often times you sweat when you are sick, which will clear up skin, and the build up of white blood cells in your body will attack any and all forms of infection which will also clear up your skin.|||natural antibody%26#039;s and blood circulation is increased plus more white calls making the skin look paler,also an increase of water con tint of the blood