You do know that this virus has a no symptoms two week latency period?
two-week latency
sure I know this. Every FReeper knows this.
We can’t diagnose a 2-week latency just by looking at someone. It’s impossible.
Just like we can’t tell a TB carrier, or a Zika carrier or a HIV carrier. The best we can do - ALL we can do - is take their temp at various checkpoints, watch for signs of illness, and isolate those showing signs of illness on their flights, just as customs does once people land.
Are some latent going to get thru? Probably. Will they be spreaders? depends on their level of morality and social responsibility. Some people are assholes. Most people aren’t. I will say anecdotally that I’ve watched a whole lot more youtube videos of returnees willing and happy to self-quarantine and limit their contacts over those who don’t care.