The difference between upper respiratory tract infections and lower respiratory tract infections mainly lies in the location of the infection. The pathogen causing the infection could be the same. If an upper respiratory tract infection is not treated in time, the pathogen might infect downwards and cause a lower respiratory tract infection. Compared to upper respiratory tract infections, which are commonly seen in clinical practice, lower respiratory tract infections are less common. Therefore, whether it is an upper or lower respiratory tract acute inflammation, sufficient and sensitive antimicrobial drugs should be chosen according to the treatment course for proper treatment.