By Betsy Todd, MPH, RN, CIC, AJN clinical editor
Middle East respiratory syndrome (MERS) first emerged in Saudi Arabia in September 2012. Until last month, most MERS cases have occurred in that country. But on May 20, South Korea reported its first laboratory-confirmed case of MERS, in a 68-year-old man who had recently returned from a business trip to the Middle East.
The diagnosis was made only after the man had visited four health care facilities since his return home. This resulted in nosocomial transmission to other patients, health care workers, and visitors. To date, the Republic of Korea’s Ministry of Health has identified 108 cases of MERS in South Korea. Nine patients (all with serious preexisting health conditions) have died.
The WHO notes that all of these cases are epidemiologically linked to the index case. That is, there is no evidence that a new “reservoir” of MERS virus has suddenly surfaced in South Korea—all cases thus far stem from the Korean traveler who acquired his infection while visiting the Arabian Peninsula.
This is the largest outbreak of MERS so far outside of the Middle East, and therefore a reason for some concern. However, person-to-person transmission of MERS is not new, and there has as yet been no sustained community transmission in South Korea or elsewhere. Readers may recall that two U.S. hospitals safely diagnosed and managed patients with MERS during the spring of 2014. These two unrelated cases in the U.S. were imported via health care providers who lived and worked in Saudi Arabia. The patients were isolated and successfully treated at Community Hospital in Munster, Indiana, and Dr. P. Phillips Hospital in Orlando, Florida, and there was no further transmission of the virus.
In response to the South Korean outbreak, the CDC has updated its case definition for “patients under investigation” to include a history of having been in a health care facility (as patient, worker, or visitor) in South Korea within 14 days of symptom onset.
This outbreak in a new geographical area reminds us once again of the importance of taking a travel history when a patient presents with signs of infection. A patient with fever and respiratory symptoms along with a relevant travel history (as described in CDC case definitions) should be placed on airborne and contact isolation precautions until infections of concern are ruled out.
For information on specimen collection and testing, infection control, and isolation measures along with updates as this outbreak continues to unfold, visit: http://www.cdc.gov/coronavirus/mers/index.htm.