Difference Between Cold and Sinus Infection

Because the symptoms can be quite similar, it can be hard to tell the difference between a sinus infection and a cold. To make matters even more confusing, sinus infections and colds frequently occur together. This makes sense, as the two conditions are often caused by the same viruses.

Within the category of sinusitis, it can be difficult to tell which type you have: viral or bacterial. Signs or symptoms that a viral infection might have turned into a bacterial sinus infection include:

Symptoms have not improved within 10 days. Often, symptoms of an upper respiratory infection may not be completely gone within 10 days; however, a sinus infection may be suspected if the symptoms don't seem to be improving at all.
Severe symptoms. Bacteria tend to cause more severe infections than viruses. If the following symptoms are present for three to four consecutive days, this may be a bacterial sinus infection:
- High fever (at least 102ºF or 39ºC)
- Thick, colored nasal discharge
- Person feels ill.

Worsening symptoms or symptoms returning ("double sickening"). In this situation, the person appears to be getting better, but on about day 6 or 7, symptoms get worse again.

(Click Cold or Sinus Infection to learn more about this topic. This article provides a table that contains helpful side-by-side comparisons of cold, flu, and sinusitis symptoms.)