Considering Revision the Criteria for Patients under Investigations for MERS-CoV Infections: Diarrhea or Not

Kim, Mi-Na; Kim, Eui-Chong

Although human-to-human transmission in Saudi Arabia is markedly decreasing, 6 the current case clearly showed that MERS-CoV patients can be imported from countries other than Saudi Arabia with atypical presentation in Korea, which will make recognition of PUI more difficult. As we learned from the Korean MERS outbreak, it is an absolute necessity to detect any influx of the MERS-CoV infections at quarantine surveillance to prevent its outbreak. There is a concern of excessive testing and preemptive isolation if diarrhea is added to the criteria of PUI of MERS because traveler's diarrhea is common. During the "watch" period of the national MERS response against the current case in 2018, a tertiary care hospital in Seoul modified the criteria for testing MERS-CoV to include patients with diarrhea associated with traveling history of Middle East countries and total of 16 patients were tested for MERS-CoV but no one was tested because of diarrhea. Therefore, addition of diarrhea in clinical features indicating PUI possibly makes surveillance for MERS infections more thorough with an affordable burden. For 7 weeks during the 2015 outbreak, a total of 27,009 MERS-CoV real-time reverse transcription PCR tests were performed to confirm PUI in clinical laboratories in Korea, 10 which would be much larger than the number of MERS tests future, regardless of PUI criteria if no more outbreak occurs. Considering the detrimental impact on the healthcare system if an index case is missed, better PUI criteria provide tighter guard in quarantine surveillance. Note again that PUI criteria are not a case definition but for testing and revision of national PUI criteria to include diarrhea as a clinical feature would be beneficial in Korea.