General Information
Respiratory infections are predominantly caused by viruses, but also by a limited number of typical bacteria species.
In almost every case, an invasion of secondary pathogens follows. Secondary pathogens take advantage of the epithelial lesions caused by primary pathogens.
In the case of massive infectious pressure, or if the host defense system is compromised by underlying pathologic conditions, clinical infection develops of often chronic or relapsing nature. In these cases especially, systemic antiinfective therapy is always indicated.
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