Fig. (1) Nasal wash nitrate in children with and without RSV subtype B-mediated influenza-like illness presenting to the emergency department during the 2009 influenza pandemic. Data include single as well as co-infections. (A) RSV-B positive vs RSV-B negative; (B) RSV-B positive vs RSV-A positive. The box depicts the range of values between the 25th and 75th percentiles with a line showing the median; whiskers encompass the adjacent values within 1.5 interquartile range of the nearer quartile.