As LG1 it really depends on the infection rate. Another good point is the .gov may try to downplay how serious it is.
Low infection rate means there's less to worry about.
Given even a moderate infection rate, say 40 percent, Given news that there was an outbreak anywhere in the country, I would be extremely cautious and should there be even mild evidence that it's spreading I would immediately go into full isolation.
With an infection rate of 75 percent in any major city in the world I probably lock the doors and see how it plays out. It's just too easy for diseases to spread from travel these days. Its not hard to have been in 5 major world cities on 3 different continents in 1 week. If there's a 7 day incubation period its not unreasonable that basically the entire world will already be infected.
It is better to remain silent and appear stupid, then to speak and remove all doubt.