We identified a total of 31 HCWs in the emergency department during his 27-min stay. Of these 31 HCWs, nine were classified as having been within 3–6 feet of the patient. These nine HCWs were quarantined at home and monitored for 14 days. If fever or respiratory symptoms developed, RT-PCR for MERS was immediately performed by the KCDC. One individual became symptomatic. Sera were collected from the other eight HCWs approximately 3 weeks after their exposure to the index patient. Serum from the symptomatic HCW, who was finally diagnosed with MERS by RT-PCR performed in the KCDC, was collected approximately 6 weeks after his exposure to the index patient upon his recovery from MERS.