It is important to note that only viable cells were included in the enumeration of immune cell populations by flow cytometry and that these numbers likely underrepresent the total immune cell infiltration, due to cell death pathways (i.e., NETosis or necrosis), and this may explain discrepancies between scarce counts of early recruiting neutrophils, which did not correlate to increased expression of MPO or ELANE in the middle ear of infected animals at 2 day post infection. Here, MPO is linked to infection.