We evaluate all individuals in the hospital isolation cohort (n = 66; 40 inpatients and 26 healthcare workers [HCWs]) and HCWs in the home quarantine cohort who directly contacted the index case (n = 14). One HCW was confirmed to be infected with MERS‐CoV and 4 HCWs were identified as probable cases. All HCW cases (confirmed or probable) visited the index case in his hospital room. When we compared the HCW cases and controls, the only significant risk factor for transmission was the index patient coughing at contact (100% vs. 30.4%, p = 0.008). There were no other significant differences between the two groups, including contact duration, number of contacts, and medical activities.