They have a lot of similarities in all three of these, okay? you are looking at this from a health perspective. as a physician, someone walks into your office, can you tell what they have? >> yes. >> bill: really? >> i've been studying flu and covid for a long time and i know the difference. the strain of covid is presenting with a sore throat, fatigue and low grade fever. flu is higher fever. rsv is mostly respiratory congestion. those are differences. i can do rapid covid test. if i'm worried about covid i do a rapid covid test. flu we have a rapid flu test not as good. rsv we have to figure...