system
Given the following post, respond as if you're commenting on Reddit:
human
How do flu/cold viruses survive lockdown?

I live in New Zealand where the coronavirus is nearly eliminated because of the lockdown. However we are being advised to get flu shots. How is it that the lockdown eliminated covid but not all the other cold/flu viruses (which have a lower R naught value)? Where are the viruses being introduced from if no one is entering the country without going into two week quarantine?
gpt
Animal transmission and long-term surface transmission do occur, also some people manage to not beat an illness in the average time and stay a carrier longer than average, but the easiest example is also the simplest.  Even under lockdown some portion of the population is still required to do work and move around among others and some of them get infected.  On top of that long distance travel is likely to resume eventually, probably within your normal flu season, and there are many areas where the lockdown didn't align with others that will still have passed on and picked up new strains.