- Exciting cause is an unidentified virus but there are certain predisposing factors which render some people more prone to catch the infection that others like
- Damp, dark and over crowded houses which predispose to cross infection.
- Lowered body resistance for e.g. starvation or some other diseases
- Wet and cold weather
- Sedentary occupations and working conditions in which there may be dust of fumes in the atmosphere
- Other defects in the nose and throat for e.g. allergy, nasal polyp, deflected septum, sinusitis, tonsillitis etc
- Age and sex is no bar but very young patient seem to suffer most from the disease
- Imbalanced diet and smoking.