The bad part of it that is going to hurt Poland is that people live in such close quarters.
I know a guy that caught it flying back from California to Detroit Michigan on a commercial flight.
Two days after he got back he noticed a dry cough and scratchy throat and the next day a very soar throat and a runny nose.
The third day he got a headache from hell that even after taking several Vicodin, that didn't even touch it, he knew that he was in trouble.
He was suffering in pure hell with this violent headache (24 hours) that he called to get tested to see if he had it.
He was told to stay home and self quarantine to see if the symptoms would get better. (he was refused testing at that point)
His doctors office did call him back the next morning to find out the poor guy had improved considerable with the headache dissipating even though he was very weak and had muscle and joint pains.
He was told to stay in lock down quarantine for two weeks from the day he first noticed the first symptoms.
The sixth day he was almost back to normal again.
The best case scenario is that you don't show any symptoms at all and the worst case (short of dying) is what I just described of what my friend experienced.
I pray for the best for everyone in Poland.