Randomized controlled trial of the effect of regular paracetamol on influenza infection

Jefferies, Sarah; Braithwaite, Irene; Walker, Steven; Weatherall, Mark; Jennings, Lance; Luck, Michelle; Barrett, Kevin; Siebers, Robert; Blackmore, Timothy; Beasley, Richard; Perrin, Kyle

Following randomization the following study assessments were performed: Pernasal flocked swabs (Copan Diagnostics, Murietta, CA, USA) were collected into Universal Transport Medium (Roche Diagnostics, Basel, Switzerland) taken for influenza quantitative viral load reverse transcriptasepolymerase chain reaction (RT-PCR) analysis at Baseline (before the first medication dose), 24 h (Day 1), 48 h (Day 2) and 120 h (Day 5). All baseline samples were tested for the presence of human ribonucleic acid (RNA) to ensure that samples had obtained human tissue; these were positive in all instances. A multiplex polymerase chain reaction (PCR) (Fast-Track Diagnostics, Junglinster, Luxemburg) was also performed on Baseline samples for other respiratory viruses. 24 Additional pernasal swabs were taken for viral culture at Baseline, Day 1 and Day 5. Blood samples were taken for analysis of serum cytokines (tumour necrosis factor α, IFN-γ and interleukin (IL)-6) at Baseline, Day 2 and Day 5. Details of virology methodology and cytokine analysis are provided in Supplementary Appendix S1.