Runny or stuffed nose/ sneezing
In the first days of infection, the nose is often runny. One of the defense mechanisms of the upper respiratory tract is excessive mucus production accompanied by sneezing. This is the body attempting to get rid of the virus from the surface of the epithelium.
As the inflammatory response and virus-induced damage intensify, mucous membranes swell, causing a stuffy nose and breathing difficulties. This symptom is not only unpleasant, but it can cause complications such as sinusitis or middle ear inflammation (due to compromised drainage of the middle ear and sinuses, mucus piles up providing perfect conditions for bacterial infection).