Respiratory Tract Infections are any infectious diseases of the upper and lower respiratory tract.
Upper Respiratory Tract Infection (sinuses and throat)
The infections are caused by virus. Upper respiratory tract (which starts at sinuses and ends at vocal chords) infection includes the common cold, laryngitis, pharyngitis/tonsillitis, acute rhinitis, acute rhinosinusitis and acute otitis media.
Lower Respiratory Tract Infection (airways and lungs)
Lower respiratory system starts at vocal chords and ends at lungs. Lower respiratory tract infections include acute bronchitis, bronchiolitis, pneumonia and tracheitis. Lower respiratory tract infections tend to last longer and can be serious.