Viral sinusitis and bacterial sinusitis
If the condition lasts longer than ten days, or there is a worsening of symptoms after five to seven days, the sinusitis is more likely caused by bacteria than a virus.
Is sinusitis always bacterial?
Sinusitis is an inflammation of the sinuses. It is often caused by bacterial (germ) infection. Sometimes, viruses and fungi (molds) cause it. People with weak immune systems are more likely to develop bacterial or fungal sinus infection.
How can you tell the difference between bacterial and viral sinusitis?
Instead, your doctor looks largely at symptom duration to determine the source of your infection. A viral sinus infection will usually start to improve after five to seven days. A bacterial sinus infection will often persist for seven to 10 days or longer, and may actually worsen after seven days.
