OBJECTIVETo analyze the epidemiological characteristics of Middle East Respiratory Syndrome (MERS) outbreak in the Republic of Korea in 2015 and provide related information for the public health professionals in China.

METHODSThe incidence data of MERS were collected from the websites of the Korean government, WHO and authoritative media in Korea for this epidemiological analysis.

RESULTSBetween May 20 and July 13, 2015, a total of 186 confirmed MERS cases (1 index case, 29 secondary cases, 125 third generation cases, 25 fourth generation cases and 6 cases without clear generation data), including 36 deaths (case fatality rate: 19%), were reported in Korea. All cases were associated with nosocomial transmission except the index case and two possible family infections. Sixteen hospitals in 11 districts in 5 provinces/municipalities in Korea reported confirmed MERS cases, involving 39 medical professionals or staff. For the confirmed cases and death cases, the median ages were 55 years and 70 years respectively, and the cases and deaths in males accounted for 60% and 67% respectively. Up to 78% of the deaths were with underlying medical conditions. Besides the index case, other 12 patients were reported to cause secondary cases, in which 1 caused 84 infections. One imported MERS case from Korea was confirmed in China on May 29, no secondary cases occurred. The viruses strains isolated from the cases in Korea and the imported case in China show no significant variation compared with the strains isolated in the Middle East.

CONCLUSIONThe epidemiological pattern of the MERS outbreak in Korea was similar to MERS outbreaks occurred in the Middle East.