MERS, or just pneumonia?

BILL* has a fever (37.9°C), a productive cough and basal rales on the right. 

woman at airport wearing a face mask

He is 56, obese, a heavy smoker and returned 10 days ago from a two-week trip to South Korea. He became ill 48 hours ago, but is not too distressed at the moment.

Diagnose pneumonia, get a chest x-ray and start the appropriate antibiotic?

Correct, but don’t forget the possibility of Middle East respiratory syndrome (MERS). If Bill has MERS,