[Medical Q&A] Does yellow nasal discharge necessarily mean a bacterial infection?

Author: Fang Xiao, The First Affiliated Hospital of Zhengzhou University

Reviewer: Wang Huaili, Chief Physician, The First Affiliated Hospital of Zhengzhou University

Yellow nasal discharge is not necessarily caused by bacterial infection. Although bacterial infection is one of the common causes of yellow nasal discharge, it may also be caused by other factors.

When the human body is infected with bacteria such as hemolytic streptococci and Staphylococcus aureus, it can cause inflammation of the nasal mucosa and lead to the production of purulent secretions, which usually contain necrotic cells, bacteria and inflammatory factors and appear yellow and purulent. At this time, the patient may have symptoms such as fever and nasal congestion and needs to seek medical attention in time. After diagnosis, amoxicillin, cefaclor and other drugs can be used for treatment under the guidance of a doctor.

However, viral infections may also cause yellow purulent nasal discharge. In the early stages of a viral cold, patients often have clear nasal discharge, which is mainly composed of water, protein, and lytic enzymes. As inflammation continues, the nasal mucosa begins to become congested and edematous, causing normal tissue fluid secretion to slow down and the concentration of nasal discharge to increase. At this time, sticky white nasal discharge appears, which often occurs on the 3rd to 6th day of a cold. As the course of the disease progresses, white blood cells also participate in the fight against the virus. When the white blood cells and the virus "die together", the "remnants" are discharged from the body through the nasal cavity, and at this time, sticky yellow or yellow-green nasal discharge will appear. Viral infections are generally self-limiting, and yellow nasal discharge usually recovers within 10 days. However, if the yellow nasal discharge persists for more than 10 days without improvement, or if the symptoms suddenly worsen after improvement, or are accompanied by fever, headache, etc., antibiotics should be used under the guidance of a doctor.

In addition, other reasons such as allergic rhinitis may also cause yellow nasal discharge. Therefore, yellow nasal discharge is not necessarily a bacterial infection, and antibiotics should not be used blindly.