Epidemiology of a Novel Recombinant Middle East Respiratory Syndrome Coronavirus in Humans in Saudi Arabia.

Background: Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe respiratory illness in humans. Fundamental questions about circulating viruses and transmission routes remain.

Methods: We assessed routinely collected epidemiologic data for MERS-CoV cases reported in Saudi Arabia during 1 January-30 June 2015 and conducted a more detailed investigation of cases reported during February 2015.