[National Surveillance and Response to Possible and Suspected Middle East Respiratory Syndrome Cases in the Republic of Korea, 2022].

Middle East Respiratory Syndrome (MERS) is an acute respiratory infection transmitted mainly through camels and individuals infected with the MERS-CoV. It was first reported in Saudi Arabia in 2012 and is predominantly prevalent in the Middle East. By 2022, there were 341 possible cases of MERS in the Republic of Korea. The winter months of January and February contributed to 30.2% (103 cases) of all reports in 2022, followed by a decrease; however, an increase was observed during the second half of the year. This is presumed to be attributed to the simultaneous response policy to coronavirus disease 2019 (COVID-19) and MERS implemented in December 2021, the international easing of COVID-19 prevention measures, an increase in travelers from the Middle East, and seasonal factors. Among the 341 possible MERS cases reported in 2022, 122 suspected MERS cases classified as underwent MERS testing with no confirmed cases. Moreover, to efficiently prevent the influx of MERS, along with COVID-19 prevention measures during the quarantine stage, a simultaneous response policy to COVID-19 and MERS was implemented in December 2021. Suspected MERS cases were transferred to quarantine facilities within the quarantine station for simultaneous testing for COVID-19 and MERS, replacing the previous practice of conducting tests after transfer to hospitals. This convenience appears to have led to the proactive reporting and surveillance of possible MERS symptoms at the quarantine stage. Therefore, we propose further analyses on the convenience of conducting MERS tests at quarantine facilities and their impact on MERS surveillance. This information can be actively utilized in the development of new MERS surveillance systems.