South Korea on Sep 8 announced that a 61-year-old man who got sick during a business trip to Kuwait tested positive for Middle East respiratory syndrome coronavirus (MERS-CoV) after arriving home, marking the country's first imported case in 3 years.
In a statement yesterday, the World Health Organization (WHO) said the man had been in Kuwait between Aug 16 and Sep 6 and was hospitalized with fever, diarrhea, and respiratory symptoms shortly after he returned to South Korea.
"While this case is unusual, it is not unexpected that MERS will occasionally appear outside of the Middle East," the WHO said, adding that implementing rapid response measures can minimize the spread of the disease. The WHO said it is in discussions with the Korea Centers for Disease Control and Prevention (KCDC) and is ready to provide support, if needed.
South Korea's case is the second recent exported MERS-CoV from the Middle East. About two and a half weeks ago, the United Kingdom announced an infection in a Saudi visitor who had a history of contact with camels.
Quick action in South Korea
In 2015, South Korea's last imported case sparked a series of hospital-related outbreaks that eventually sickened 186 people, 36 of them fatally.
Maria Van Kerkhove, PhD, the WHO's technical lead for MERS-CoV, told CIDRAP News that, after its 2015 outbreak, South Korea made substantial changes to its entire public health system, from the legislative level down to detection and investigation.
"In this instance, the Korean authorities very quickly suspected MERS and isolated the patient immediately," she said. "Contact tracing is still ongoing, and we may see some secondary infections, but this quick action likely prevented many human cases in Korea."
KCDC early investigation findings
According to a machine translation of a KCDC press release today, the man was at the airport in Incheon for 26 minutes before a taxi took him to Samsung Hospital Seoul, where he was evaluated for more than 4 hours before he was taken to Seoul National University Hospital, a designated isolation hospital.
So far, 417 contacts, including airline passengers, have been identified, and 21 of those are defined as close contacts who are under monitoring.
While in Kuwait, the man was living in a work facility and experienced abdominal symptoms and diarrhea on Aug 28, for which he sought hospital treatment on Sep 4. He reported no contact with camels, and an investigation into his medical care in Kuwait and how he contracted the virus is under way.
In Kuwait, the man's contacts include 20 South Korean workers living in two or three facilities.
He flew back to South Korea through Dubai in the United Arab Emirates, sitting next to one of his coworkers. The list of close contacts includes eight airline passengers and four crew members.
At the airport, the quarantine officer said the man did not have a fever or respiratory symptoms. Before leaving the airport, he called a doctor at Samsung Medical Center to report his symptoms, which included weakness and diarrhea.
During his workup at the hospital, his body temperature was elevated, and chest x-rays suggested pneumonia and that he was possibly infected with MERS-CoV.
A reminder that MERS hasn't gone away
MERS-CoV is actively circulating in dromedary camels in large parts of the Middle East and beyond, and health officials expect human cases to continue, Van Kerkhove said.
The two recent exported cases are unrelated—the UK MERS patient likely contracted the virus from camels in Saudi Arabia, while the South Korean patient had been to Kuwait on business, she said, adding that Kuwait's health ministry is investigating the man's actions and exposures before he became ill. Kuwait has reported four MERS cases since 2012, with its most recent on in 2015, Van Kerkhove said.
"Kuwait has also reported circulating of MERS-CoV in dromedary camels in the country."
One of the main messages from the two recent cases is that MERS-CoV hasn't gone away, she said. "This high threat respiratory pathogen may be rare, but MERS is a global threat and each human case has the potential to start a large outbreak."
Although early recognition, applying standard infection prevention and control practices, and comprehensive contact tracing and follow-up have dramatically cut human-to-human transmission in health settings, especially in Saudi Arabia, Van Kerkhove said health officials haven't had as much success reducing community infections from contact with infected camels.
"Until we can reduce spillover, cases will continue to occur and cases will continue to be exported to other countries," she said.
Sep 9 WHO statement
Sep 10 KCDC press release (in Korean)