Table 5. Residual clinical specimens from the 2015/16 United States national influenza surveillance tested using iART (n = 85).

Type and subtype	Number of specimens testeda	Number of. indeterminateb	Number of nonresistantc	Number of resistantc	NA mutation in resistant virusesd
A(H1N1)pdm09	34	9	19	6	H275Y
A(H3N2)	25	5	18	2	E119V
B	26	3	22	1	K152N
Total	85	17	59	9	Not applicable

NA: neuraminidase.

^a Leftovers of clinical specimens submitted for United States national virological surveillance that satisfied the following criteria: (i) NA sequencing or pyrosequencing data were available; (ii) virus was recovered in cell culture and tested using NAI assay. For testing using iART, 0.1 mL of a residual clinical specimen was combined with 0.4 mL of viral transport medium (VTM, Becton Dickinson) to bring the final volume to 0.5 mL.

^b Indeterminate: specimen displayed a low signal to noise ratio (SNR); insufficient NA activity for testing.

^c Output result as shown on the device’s display; result is based on the pre-set cutoffs for influenza A (≥ 0.7) and B (≥ 2.2) viruses.

^d Position of amino acid residue shown using straight NA numbering (Table 1).