Nosocomial outbreak of severe fever with thrombocytopenia syndrome among healthcare workers in a single hospital in Daegu, Korea.

BACKGROUND: In August 2020, 17 healthcare workers (HCWs) were simultaneously diagnosed with severe fever with thrombocytopenia syndrome (SFTS) at a university hospital in Daegu, Republic of Korea. METHODS: An epidemiologic investigation using questionnaires was conducted for all suspected HCWs who had viral infection symptoms or who had the possibility of exposure to the index patient. RESULTS: A total of 17 HCWs infected with the SFTS virus (SFTSV) (28.8%) were identified among the 59 HCWs who had contact with the patient. Operating a bag valve mask during cardiopulmonary resuscitation (CPR) (OR 7.50, 95% CI 1.75-41.07), cardiac massage during CPR (OR 12.00, 95% CI 1.76-241.94), exposure to the patient's body fluids (OR 7.43, 95% CI 1.91-34.69), and shorter individual hospital work experience periods (OR 6.79, 95% CI 1.70-32.10) were significantly associated with SFTS infection in the univariate analysis. However, exposure to body fluids was found to be the only statistically significant risk factor when multivariate analysis was conducted (OR 6.27. 95% CI 1.23-42.81, p = 0.036). CONCLUSIONS: This finding illustrates the importance of wearing appropriate personal protective equipment in treatment areas and when conducting any medical procedures, including CPR for patients with SFTS, and any procedure that involves potential exposure to body fluids.

Detection and Isolation of SARS-CoV-2 in Serum, Urine, and Stool Specimens of COVID-19 Patients from the Republic of Korea.

OBJECTIVES: Coronavirus Disease-19 (COVID-19) is a respiratory infection characterized by the main symptoms of pneumonia and fever. It is caused by the novel coronavirus severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2), which is known to spread via respiratory droplets. We aimed to determine the rate and likelihood of SARS-CoV-2 transmission from COVID-19 patients through non-respiratory routes. METHODS: Serum, urine, and stool samples were collected from 74 hospitalized patients diagnosed with COVID-19 based on the detection of SARS-CoV-2 in respiratory samples. The SARS-CoV-2 RNA genome was extracted from each specimen and real-time reverse transcription polymerase chain reaction performed. CaCo-2 cells were inoculated with the specimens containing the SARS-COV-2 genome, and subcultured for virus isolation. After culturing, viral replication in the cell supernatant was assessed. RESULTS: Of the samples collected from 74 COVID-19 patients, SARS-CoV-2 was detected in 15 serum, urine, or stool samples. The virus detection rate in the serum, urine, and stool samples were 2.8% (9/323), 0.8% (2/247), and 10.1% (13/129), and the mean viral load was 1,210 ± 1,861, 79 ± 30, and 3,176 ± 7,208 copy/µL, respectively. However, the SARS-CoV-2 was not isolated by the culture method from the samples that tested positive for the SARS-CoV-2 gene. CONCLUSION: While the virus remained detectable in the respiratory samples of COVID-19 patients for several days after hospitalization, its detection in the serum, urine, and stool samples was intermittent. Since the virus could not be isolated from the SARS-COV-2-positive samples, the risk of viral transmission via stool and urine is expected to be low.

Cloning and Expression of Recombinant Tick-Borne Encephalitis Virus-like Particles in Pichia pastoris.

OBJECTIVES: The purpose of this study was to verify the feasibility of using the glyceraldehyde-3-phosphate dehydrogenase (GAP) promotor based Pichia pastoris expression system to produce tick-borne encephalitis virus (TBEV) virus-like particles (VLPs). METHODS: The complementary DNA encoding the TBEV prM signal peptide, prM, and E proteins of TBEV Korean strain (KrM 93) was cloned into the plasmid vector pGAPZɑA, then integrated into the genome of P. pastoris, under the control of the GAP promoter. Expression of TBEV VLPs was determined by Western blotting using monoclonal antibody against TBEV envelope (E) protein. RESULTS: Recombinant TBEV VLPs consisting of prM and E protein were successfully expressed using the GAP promoter-based P. pastoris expression system. The results of Western blotting showed that the recombinant proteins were secreted into the culture supernatant from the P. pastoris and glycosylated. CONCLUSION: This study suggests that recombinant TBEV VLPs from P. pastoris offer a promising approach to the production of VLPs for use as vaccines and diagnostic antigens.