Clinical Presentation and Outcomes of Middle East Respiratory Syndrome in the Republic of Korea

Choi, Won Suk; Kang, Cheol-In; Kim, Yonjae; Choi, Jae-Phil; Joh, Joon Sung; Shin, Hyoung-Shik; Kim, Gayeon; Peck, Kyong Ran; Chung, Doo Ryeon; Kim, Hye Ok; Song, Sook Hee; Kim, Yang Ree; Sohn, Kyung Mok; Jung, Younghee; Bang, Ji Hwan; Kim, Nam Joong; Lee, Kkot Sil; Jeong, Hye Won; Rhee, Ji-Young; Kim, Eu Suk; Woo, Heungjeong; Oh, Won Sup; Huh, Kyungmin; Lee, Young Hyun; Song, Joon Young; Lee, Jacob; Lee, Chang-Seop; Kim, Baek-Nam; Choi, Young Hwa; Jeong, Su Jin; Lee, Jin-Soo; Yoon, Ji Hyun; Wi, Yu Mi; Joung, Mi Kyong; Park, Seong Yeon; Lee, Sun Hee; Jung, Sook-In; Kim, Shin-Woo; Lee, Jae Hoon; Lee, Hyuck; Ki, Hyun Kyun; Kim, Yeon-Sook

Since its initial identification in Saudi Arabia in 2012, 1,638 cases of laboratory-confirmed MERS-CoV infection have been reported as of February 26th, 2016. In that time interval, another multi-facility outbreak in an endemic area has occurred since the first healthcare facility-related outbreak was reported by Assiri, et al [9] . Here, we describe the clinical findings of 186 MERS patients in the Republic of Korea from May through September 2015. To the best of our knowledge, this is the largest report of an outbreak outside of the Middle East. In this study of the MERS outbreak in the Republic of Korea, the reported data suggest that MERS-CoV is most likely to be transmitted as a healthcare-associated infection. No communi- ty-associated infections lacking any history of contact with MERS-CoV were found in this outbreak. Even though the overall transmissibility of MERS-CoV was relatively low, there were several so-called 'super-spreading' events posing a serious threat to public health. Rapid transmission and high attack rates in dialysis units were noted, in a previous report, in Saudi Arabia [5] . However, no additional cases in dialysis units were reported in this Korean outbreak, even though many patients undergoing hemodialysis were exposed to MERS in dialysis units. This apparent heterogeneity in transmission, with many infected patients not transmitting disease at all and several patients transmitting disease to others, may be characteristic of MERS-CoV infections, similar to SARS [4, 5, 10, 11] .