Molecular Epidemiology of Hospital Outbreak of Middle East Respiratory Syndrome, Riyadh, Saudi Arabia, 2014

• Main Authors: Shamsudeen F. Fagbo, Leila Skakni, Daniel K.W. Chu, Musa A. Garbati, Mercy Joseph, Ahmed M. Hakawi
• Format: Article
• Language: English
• Published: Centers for Disease Control and Prevention 2015-11-01
• Series: Emerging Infectious Diseases
• Subjects: Middle East respiratory syndrome; MERS; Middle East respiratory syndrome coronavirus; MERS-CoV; coronavirus; viruses
• Online Access: https://wwwnc.cdc.gov/eid/article/21/11/15-0944_article

We investigated an outbreak of Middle East respiratory syndrome (MERS) at King Fahad Medical City (KFMC), Riyadh, Saudi Arabia, during March 29–May 21, 2014. This outbreak involved 45 patients: 8 infected outside KFMC, 13 long-term patients at KFMC, 23 health care workers, and 1 who had an indeterminate source of infection. Sequences of full-length MERS coronavirus (MERS-CoV) from 10 patients and a partial sequence of MERS-CoV from another patient, when compared with other MERS-CoV sequences, demonstrated that this outbreak was part of a larger outbreak that affected multiple health care facilities in Riyadh and possibly arose from a single zoonotic transmission event that occurred in December 2013 (95% highest posterior density interval November 8, 2013–February 10, 2014). This finding suggested continued health care–associated transmission for 5 months. Molecular epidemiology documented multiple external introductions in a seemingly contiguous outbreak and helped support or refute transmission pathways suspected through epidemiologic investigation.