Flu due to ident novel influenza A virus w oth manifest

This code signifies an influenza infection caused by a newly identified influenza A virus strain, distinct from seasonal or previously classified pandemic strains. The patient presents with symptoms beyond typical respiratory involvement, indicating systemic or other organ system manifestations.

Apply this code when documentation clearly states influenza due to a "novel influenza A virus" and describes additional complications or manifestations beyond uncomplicated respiratory illness. This includes conditions like pneumonia, myocarditis, or encephalopathy directly attributed to the novel influenza A infection.

• Requires physician documentation explicitly stating "novel influenza A virus."
• Do not use for seasonal influenza or H1N1 (swine flu) unless specifically identified as a novel strain.
• Sequence this code first as the primary diagnosis when it is the reason for the encounter.