Coughing up yellow sputum not only does not mean that your condition is getting better, but it is often indicative of a bacterial infection in combination with the common cold, which means that your condition is getting worse and usually requires antibacterial treatment. Colds, i.e. upper respiratory tract infections, are usually caused by viral infections such as adenoviruses, rhinoviruses and influenza viruses, which do not usually cause yellow sputum. Bacterial infections such as hemolytic streptococcus can also cause yellow sputum. Therefore, coughing up yellow sputum during the course of a cold is usually indicative of a bacterial infection and often requires the addition of bacterial antibiotics such as penicillin, ceftazidime, and azithromycin. If you have a cough with yellow sputum, it is recommended to go to the hospital as soon as possible, under the guidance of the doctor to standardize the treatment.