<< There are less cases of the coronavirus in Vietnam than there is in the United States as of today and the US number is only 11. So relax. >>
Well, it seems that Vietnam isn't relaxing.
"Vietnam is setting up field hospitals with thousands of beds to handle a potential influx of coronavirus cases."
Note that Vietnam is setting up hospitals. You might note that the word "hospital" is plural. So they aren't setting up 1 hospital, but multiple.
In addition, the hospitals will have "thousands of beds".
So it seems that the government of Vietnam is expecting a huge outbreak and they are trying to prepare as best that they can.
They wouldn't be spending all of that time, manpower, and money if they were only expecting a few cases.