We report a retrospectively identified fatal case of severe fever with thrombocytopenia syndrome (SFTS) in South Korea from 2012. SFTS virus was isolated from the stored blood of the patient. Phylogenetic analysis revealed this isolate was closely related to SFTS virus strains from China and Japan.

In December 2019, a viral pneumonia outbreak caused by a novel betacoronavirus, the 2019 novel coronavirus (2019-nCoV), began in Wuhan, China. We report the epidemiological and clinical features of the first patient with 2019-nCoV pneumonia imported into Korea from Wuhan. This report suggests that in the early phase of 2019-nCoV pneumonia, chest radiography would miss patients with pneumonia and highlights taking travel history is of paramount importance for early detection and isolation of 2019-nCoV cases.

NCT00890708.

We investigated the kinetics of the Middle East respiratory syndrome coronavirus (MERS-CoV) neutralizing and spike protein antibody titers over the course of 1 year in 11 patients who were confirmed by reverse transcription PCR to have been infected during the outbreak in South Korea in 2015. Robust antibody responses were detected in all survivors who had severe disease; responses remained detectable, albeit with some waning, for <1 year. The duration of viral RNA detection (but not viral load) in sputum significantly correlated with the antibody response magnitude. The MERS S1 ELISA antibody titers correlated well with the neutralizing antibody response. Antibody titers in 4 of 6 patients who had mild illness were undetectable even though most had evidence of pneumonia. This finding implies that MERS-CoV seroepidemiologic studies markedly underestimate the extent of mild and asymptomatic infection. Obtaining convalescent-phase plasma with high antibody titers to treat MERS will be challenging.

No potential conflict of interest relevant to this letter was reported. The authors reply: Campochiaro and Caruso are correct that mention of cardiovascular associations with ankylosing spondylitis and axial spondyloarthritis, including specific conductionsystem lesions and aortic-root lesions, was largely absent from our review of spondyloarthritis. These specific lesions are uncommon and tend to occur late in the disease course, as does the other more common but less specific cardiovascular illness mentioned in their letter. The focus of our article was on early diagnosis and clinical management of the axial disease, and this priority, along with space and citation limitations, precluded our describing specific cardiovascular manifestations. Rudwaleit M, van derRudwaleit and colleagues make the important point that diagnosis in clinical practice cannot be based solely on fulfillment of classification criteria. We tried to make this point in the article, but perhaps our wording conveyed some unintended ambiguity. In order to introduce the new concept of axial spondyloarthritis, we described the classification criteria for this entity proposed by the ASAS in 2009. In discussing this concept, including the critical role of MRI, we referred to this entity as a diagnosis, in the sense of its being a defined medical condition. We did not intend by this to imply that one can rely strictly on these criteria to establish a diagnosis in clinical practice. In fact, we stated explicitly, "These classification criteria have limited use outside the arena of clinical research," to introduce the algorithm (in Fig. 2 of our article) for use in clinical practice.The algorithm itself is a modification of one published by the correspondents and their colleagues, 1 but it was modified specifically to further emphasize the importance of weighing clinical data and post-test probabilities 2 and of applying clinical judgment to the diagnostic process. Moreover, the discussion of MRI findings includes mention of lesions that are not part of the classification criteria but that can be helpful in supporting a diagnosis in clinical practice. Finally, the Summary section in our article reemphasizes the potential difficulty in accurately establishing or ruling out a diagnosis of axial spondyloarthritis, with no mention of criteria. Viral Load Kinetics of MERS Coronavirus InfectionTo the Editor: The outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV) infection in South Korea involved 186 patients and resulted in 38 deaths, with four large hospital outbreaks accounting for 82% of the total cases. 1,2 Here, we report changes in viral load over time in patients with MERS.We included all patients who were admitted to three Seoul National University-affiliated hospitals; the institutional review boards of these hospitals approved this study and waived the need for written informed consent on public health grounds. The patients were categorized into a group with severe disease (severe group) or a group with mild disease (mild grou...

Clinical progression over time and cytokine profiles have not been well defined in patients with Middle East respiratory syndrome coronavirus (MERS-CoV) infection. We included 17 patients with laboratory-confirmed MERS-CoV during the 2015 outbreak in Korea. Clinical and laboratory parameters were collected prospectively. Serum cytokine and chemokine levels in serial serum samples were measured using enzyme-linked immunosorbent assay. All patients presented with fever. The median time to defervescence was 18 days. Nine patients required oxygen supplementation and classified into severe group. In the severe group, chest infiltrates suddenly began to worsen around day 7 of illness, and dyspnea developed at the end of the first week and became apparent in the second week. Median time from symptom onset to oxygen supplementation was 8 days. The severe group had higher neutrophil counts during week 1 than the mild group (4,500 vs. 2,200/µL, P = 0.026). In the second week of illness, the severe group had higher serum levels of IL-6 (54 vs. 4 pg/mL, P = 0.006) and CXCL-10 (2,642 vs. 382 pg/mL, P < 0.001). IFN-α response was not observed in mild cases. Our data shows that clinical condition may suddenly deteriorate around 7 days of illness and the serum levels of IL-6 and CXCL-10 was significantly elevated in MERS-CoV patients who developed severe diseases.

Novel coronavirus (SARS-CoV-2) is found to cause a large outbreak started from Wuhan since December 2019 in China and SARS-CoV-2 infections have been reported with epidemiological linkage to China in 25 countries until now. We isolated SARS-CoV-2 from the oropharyngeal sample obtained from the patient with the first laboratory-confirmed SARS-CoV-2 infection in Korea. Cytopathic effects of SARS-CoV-2 in the Vero cell cultures were confluent 3 days after the first blind passage of the sample. Coronavirus was confirmed with spherical particle having a fringe reminiscent of crown on transmission electron microscopy. Phylogenetic analyses of whole genome sequences showed that it clustered with other SARS-CoV-2 reported from Wuhan.Coronaviruses (CoVs), within the order Nidovirales, are enveloped, single-strand, positivesense RNA viruses with a large genome of approximately 30 kbp in length. CoV was cultured for the first time in human embryonic tracheal organ cultures by Tyrrell and Bynoe in 1965, 1 and it was named as 'corona' due to crown-like appearance of the surface projections on electron microscopy. All CoVs develop only in the cytoplasm of infected cells, bud into cytoplasmic vesicles, and then extrude in virus particles of 70-80 nm in diameter by exocytic secretory pathway.Among four genera of CoVs, beta-CoV includes five subgenus-embevovirus, sarbecovirus including severe acute respiratory syndrome (SARS)-CoV, merbecovirus including Middle East respiratory syndrome (MERS)-CoV, nobecovirus, and hibecovirus. Because CoVs can infect a variety of animals, SARS-CoV and MERS-CoV crossed the species barriers.Since December 2019, 2019 novel CoV (SARS-CoV-2) has been making a large outbreak involving 49,053 laboratory-confirmed patients and 1,383 mortality in 25 countries including J Korean Med Sci. 2020 Feb 24;35(7):e84 https://doi.

Middle East Respiratory Syndrome coronavirus (MERS-CoV) was first isolated from a patient with severe pneumonia in 2012. The 2015 Korea outbreak of MERSCoV involved 186 cases, including 38 fatalities. A total of 83% of transmission events were due to five superspreaders, and 44% of the 186 MERS cases were the patients who had been exposed in nosocomial transmission at 16 hospitals. The epidemic lasted for 2 months and the government quarantined 16,993 individuals for 14 days to control the outbreak. This outbreak provides a unique opportunity to fill the gap in our knowledge of MERS-CoV infection. Therefore, in this paper, we review the literature on epidemiology, virology, clinical features, and prevention of MERS-CoV, which were acquired from the 2015 Korea outbreak of MERSCoV.