FICTION 

I grew up hearing that a clear runny nose means a virus and a green or yellow nose means a bacterial infection, so it no surprise to me that others have heard it too. The only problem is that it is simply not true. I only wish it were that easy. The truth is that an antibiotic will never treat/cure a virus, and most colds are caused by viruses.

The average virus lasts 7-10 days. Throughout the duration of the virus, it is very common for the runny nose to change from a thin and clear to thick and yellow or green. The key is in how long the patient has had symptoms and are they getting better or worse? Generally viruses resolve on its own, whereas a bacterial infection will not. If symptoms are getting worse and have lasted more than 14 days, then there is concern for a bacterial infection, especially of the ears or sinuses. It isn’t that the virus turned into a bacterial infection, but it may have provided the perfect environment for the bacteria to invade (a compromised host with the warm, moist environment of a clogged sinus). Most often, the patient will also have accompanying worsening of symptoms (e.g., fever, headache, sinus pressure).

The bacteria most commonly responsible for runny noses and colds are Streptococcus pneumoniae, H. influenzae, and Moraxella caterrhalis. The importance of knowing these bacteria are that there are immunizations that help protect against the first two. Immunizations are an important armament against these bacteria, especially since over prescribing of antibiotics (for such things as viruses) are contributing to ever increasing antibiotic resistance.