Towards the end of the episode, Charlie and the woman from the CDC are discussing the differences between the two strains of Spanish Flu. They overlay two images of nucleic acids in order to find differences between them in hopes of finding a treatment.

However, they are showing images of DNA. You can tell it is DNA because the "rungs" of the ladder structure are horizontal (the B form). As they stated correctly earlier in the episode, influenze is an RNA virus. It never forms a DNA intermediate.

What is more, influenza is a single-stranded RNA virus, it does not form double-stranded RNA. If it were to, however, it would not look like DNA. Double-stranded RNA takes a form where the "rungs" are at a significant angle (the A form).