The CDC is only mandating screening in the US for flights from Iran and China

People from Iran, Italy and South Korea are meant to be screened before they board their flights 

Whether or not that is actually happening is of concern; several people have been able to return to the US from Italy recently with the virus 

One Vice journalist says she walked through JFK on Thursday after returning from Milan - Italy's virus epicenter - without anyone stopping her 

On top of that, it's unclear what the screening is meant to look like and if it will be effective

Many of the people now diagnosed with coronavirus in the US do not have symptoms, so it's unclear if a temperature check would be sufficient

New York City Mayor Bill de Blasio has asked people returning from all five countries to self-isolate for 14 days as a precaution