Clinical correlation of influenza and respiratory syncytial virus load measured by digital PCR

Hijano, Diego R.; Brazelton de Cardenas, Jessica; Maron, Gabriela; Garner, Cherilyn D.; Ferrolino, Jose A.; Dallas, Ronald H.; Gu, Zhengming; Hayden, Randall T.

Analytic specificity was 100% for influenza B. The positive predictive value was 1 and the negative predictive value was 0.682 (S1 Table) . Plotted linearity for influenza B had an R 2 value of 0.9887 (S1 Fig). Within run variation ranged from 0.06% CV to 0.56% CV for the high control, and 0.49% to 8.37% CV for the low control. Between run variation was 0.35% CV for the high control and 4.8% CV for the low control (S3 Table) . The limit of detection, limit of quantitation, and cutoff for positivity coincided at 3.309 log 10 copies/mL. Analytic specificity for RSV was 100%. The positive predictive value was 0.969 and negative predictive value was 0.565 (S1 Table) . Plotted linearity for RSVA had an R 2 value of 0.96, while plotted linearity for RSVB had an R 2 value of 0.93 (S1 Fig). The within run variation ranged from 0.05% CV to 0.55% CV for the high control and 0.56% to 0.94% for the low control. The between run variation was 0.31% CV for the high control and 0.86% CV for the low control (S4 Table) . The limit of detection, limit of quantitation, and cutoff for positivity coincided at 3.389 log 10 copies/mL. No cross-reactivity was detected for any of the three assays.