An overview and analysis of the factors underlying the recent Middle East respiratory syndrome coronavirus (MERS-CoV) outbreak in Korea has been published online ahead of print in the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine.

The authors attribute the quick spread of the outbreak to factors similar to those seen in the Middle East, including poor infection prevention and control measures and overcrowding in emergency rooms and medical wards.

Additional factors unique to South Korea, including the seeking of medical attention in different healthcare facilities and inviting family members and friends to stay in already crowded healthcare facilities, also contributed to the outbreak.

Other potential risk factors named by the authors include the use of aerosol-generating procedures, poor ward ventilation, and environmental contamination.

“As the infection was unexpected and unfamiliar to most clinicians and the general public in Korea in the initial period, the infection spread quickly within and across health care facilities, leading to 175 confirmed cases as of 23 June 2015 in several large hospital clusters,” write co-authors David S Hui, MD, of the Chinese University of Hong Kong,  and Malik Peiris, DPhil, of the University of Hong Kong.

“The Korean hospital clusters and export of an active case to Huizhou, China highlight the importance of implementation of stringent hospital infection control and prevention measures, contact tracing and mandatory quarantine for close contacts, strengthening of public health surveillance in addition to increasing the availability of isolation rooms,” the authors write.

“While the spread of MERS-CoV infection to Korea, China, and Thailand has posed challenges to the clinicians and hospital administrators, this has also provided an opportunity to try to tackle many unanswered questions, including the mode and risk factors of MERS-CoV transmission in health care settings, pathogenesis, prognostic factors, viral kinetics in relation to infectivity, serological response, and optimal treatment including the role of convalescent plasma and monoclonal antibody.”