system
Given the following post, respond as if you're commenting on Reddit:
human
Where does the flu virus go when it's not flu season? What is the reservoir it uses to come back from each year?
gpt
Sick people. Flu season is just the time of year when the rate of infection by flu increases ~1,000%. But all year long it’s still steadily transmitting itself from person to person, there is no flu off-season unfortunately.