"Severe cold" can be translated as "重感冒" in Engpsh.

The term "cold" typically refers to a viral infection of the upper respiratory tract that causes symptoms such as runny nose, cough, and sore throat. A "severe cold" usually refers to a more severe form of the common cold, with more intense symptoms and potentially comppcations.

Examples in Engpsh:

I've been down with a severe cold for the past week.
I caught a bad case of severe cold on my trip to the mountains.

Translations:

我过去一周都在患重感冒。
我去山区时得了一场严重的感冒。