Methods, pharmaceutical compositions, and systems are provided which
include a method for treating a pulmonary viral infectious disease in a
subject. The method includes administering a pharmaceutical composition
including at least one agent to a pulmonary tissue of the subject,
wherein the pharmaceutical composition is administered as two or more
distinct and non-overlapping particle size ranges configured to contact
two or more levels of pulmonary tissue of the subject, wherein the at
least one agent is configured to achieve a selected pH range in the two
or more levels of pulmonary tissue of the subject.