vol21no7_pdf-version

Imported Case of MERS, United States, 2014seems less able than SARS-CoV to spread from personto-person(23–26). Reports from the SARS-CoV epidemicshowed tertiary transmission to >100 people, and 20% ofhealth care workers become infected from the index patient(24,27). Most documented clusters of MERS-CoV infectionshow limited spread outside certain hospital settings,and unlike transmission in the SARS-CoV epidemic, therehave been no foci of sustained transmission outside of theMERS-CoV infection epicenter in and near the ArabianPeninsula (23). However, as with SARS-CoV, the risk forMERS-CoV transmission may vary by patient, and healthcare facilities must maintain a high index of suspicion andimmediately institute appropriate infection control practicesfor suspected cases.This investigation is unique because we had independentdocumentation of duration of exposure from GPSbasedtracer tags for 20% of HCP contacts. Most HCP contactsaccurately reported case-patient exposure. However,HCP with the most contact had poorer recall accuracy, and20 minutes’ difference in exposure may alter the HCP contactrisk, given that each visit was generally