Upper respiratory tract infections are clinically categorized as respiratory diseases and occur at a very high frequency. Patients with upper respiratory tract infections generally recover easily as long as their immune system is in good condition. Most upper respiratory infections are caused by viruses, and patients with decent immune function can often recover without medication within about a week. However, some infections in the upper limbs, which may be caused by bacteria or mycoplasma, present various clinical symptoms such as nasal congestion, runny nose, fever, and cough. Patients like these generally require appropriate anti-infection treatment, as well as medication to combat the mycoplasma, and their recovery might take slightly longer.