Outbreaks of Middle East Respiratory Syndrome in Two Hospitals Initiated by a Single Patient in Daejeon, South Korea

Abstract

BackgroundA Middle East Respiratory Syndrome coronavirus (MERS-CoV) outbreak in South Korea in 2015 started by a single imported case and was amplified by intra- and inter-hospital transmission. We describe two hospital outbreaks of MERS-CoV infection in Daejeon caused by a single patient who was infected by the first Korean case of MERS.Materials and MethodsDemographic and clinical information involving MERS cases in the Daejeon cluster were retrospectively collected and potential contacts and exposures were assessed. The incubation periods and serial intervals were estimated. Viral RNAs were extracted from respiratory tract samples obtained from the index case, four secondary cases and one tertiary case from each hospital. The partial S2 domain of the MERS-CoV spike was sequenced.ResultsIn Daejeon, a MERS patient (the index case) was hospitalized at Hospital A in the first week of illness and was transferred to Hospital B because of pneumonia progression in the second week of illness, where he received a bronchoscopic examination and nebulizer therapy. A total of 23 secondary cases (10 in Hospital A and 13 in Hospital B) were detected among patients and caregivers who stayed on the same ward with the index case. There were no secondary cases among healthcare workers. Among close hospital contacts, the secondary attack rate was 15.8% (12/76) in Hospital A and 14.3% (10/70) in Hospital B. However, considering the exposure duration, the incidence rate was higher in Hospital B (7.7/100 exposure-days) than Hospital A (3.4/100 exposure-days). In Hospital B, the median incubation period was shorter (4.6 days vs. 10.8 days), the median time to pneumonia development was faster (3 days vs. 6 days) and mortality was higher (70% vs. 30.8%) than in Hospital A. MERS-CoV isolates from 11 cases formed a single monophyletic clade, with the closest similarity to strains from Riyadh.ConclusionExposure to the MERS case in the late stage (2nd week) of diseases appeared to increase the risk of transmission and was associated with shorter incubation periods and rapid disease progression among those infected. Early detection and isolation of cases is critical in preventing the spread of MERS in the hospital and decreasing the disease severity among those infected.

Unusual presentation of Middle East respiratory syndrome coronavirus leading to a large outbreak in Riyadh during 2017

“…In MERS-COV, previous reports have attributed this phenomenon to either a very high viral load in the upper airway secretions of the index case (usually related to exposure to patients in the later stage of disease; that is, the second week of illness]), excessive cough or aerosol-generating procedures, or/and delayed diagnosis and improper isolation of the index case due to other illnesses known to mask MERS-CoV clinical presentation (eg, chronic renal failure and chronic heart disease). [6][7][8][9] In this report, we describe a patient who presented with acute renal failure requiring hemodialysis and became a MERS-CoV superspreader igniting a recent multihospital outbreak in Riyadh. We describe the outbreak at King Saud Medical City (KSMC).…”

No molecular evidence of MERS-CoV circulation in Jeddah, Saudi Arabia between 2010–2012: a single-center retrospective study

“…Unlike SARS-CoV which disappeared within a couple of years from its introduction, MERS-CoV continues to be endemic in the Arabian Peninsula since its emergence with high potential to cause global spread as recently observed in South Korea [11]. Nonetheless, the progression pattern of the two viruses seems to be somewhat similar in terms of their initial sporadic introduction, eventual establishment, and sustained dissemination in humans [12,13].…”

“…Nonetheless, the progression pattern of the two viruses seems to be somewhat similar in terms of their initial sporadic introduction, eventual establishment, and sustained dissemination in humans [12,13]. Indeed, MERS-CoV started by causing sporadic infections in mid 2012 which then progressed to a sustained human-to-human transmission causing several hospital and household outbreaks with global spread in some occasions [4,11].…”

A multi-faceted approach of a nursing led education in response to MERS-CoV infection

“…The initial targeted groups were healthcare workers at the first patients encounter. Multiple outbreaks had occurred in emergency rooms [6,[19][20][21][22] highlighting the importance of having healthcare workers working in these areas as the primary focus of education and training. Having a dedicated staff who were trained and well informed about the virus, its transmission and techniques and processes of infection control had a great positive impact on alleviating anxiety and fear.…”