An outbreak of carbapenem-resistant Acinetobacter baumannii in an isolation ward for COVID-19 and successful outbreak control with infection control measures

Background. The superinfection of multidrug-resistant bacteria is an important complication in critically ill COVID-19 patients. An outbreak of carbapenemresistant Acinetobacter baumannii (CRAB) occurred in an isolation ward for COVID-19. We performed an outbreak investigation, and successfully controlled the outbreak with the enhanced environmental cleaning and additional gowning and gloving. Methods. This study analyzed all COVID-19 patients with CRAB in any specimen, who admitted to an isolation ward for COVID-19 of a tertiary hospital in South Korea from October to November 2021. Results. During the outbreak period, a total of 23 patients with COVID-19 and CRAB were identified (Figure 1). Index case was 85-year old female patient who was referred from a long-term care facility. The mean age of cases was 72.9 and 14 (60.9%) patients were male. In most patients (91.3%), CRAB were identified in sputum culture, two were identified in blood culture at initial, and four patients were identified in sputum and blood culture at the same time. Most of the patients were applying high flow nasal cannula (26.1%) or mechanical ventilation (60.9%)(Table1). As shown in figure2, CRAB outbreak occurred mainly in the wards around the index case, and in particular, environmental culture was carried out in the area marked with a rectangle. CRAB was cultured on the floor, air inlet, air outlet, and window frame of the ward except for wards 3305 and 3319. Phenotypic antimicrobial resistance patterns of CRAB isolates from patients and environment were identical, and additional whole genome sequencing analyses are ongoing to find the clonality of isolates. We applied the infection control measures with the enhanced environmental cleaning using sodium hypochlorite(NaClO) 1000ppm and phenolic compounds more than twice a day, enhanced hand hygiene, and additional gowning and gloving over personal protective equipment (PPE) mandatory for COVID-19 on 29th October. No additional CRAB cases occurred since 2nd November 2021 for two weeks. Conclusion. Even when PPEs and precautions for COVID-19 are applied to isolation wards for COVID-19, it is helpful for preventing transmission of multidrug-resistant bacteria to apply additional contact precautions and environmental cleaning.

Clinical accuracy and utility of plasma microbial cell free DNA NGS for the diagnosis of invasive aspergillosis in patients with hematologic malignancy and COVID-19

Background. Invasive aspergillosis (IA) is a great threat to the severely immunocompromised and patients with coronavirus disease (COVID-19). However, diagnosis of IA is often difficult due to need for invasive biopsy and low sensitivity of other diagnostic tests. Next-generation sequencing (NGS) of plasma cell free DNA (cfDNA) can be a novel non-invasive diagnostic modality. We evaluated the clinical accuracy and utility of microbial cfDNA NGS for the diagnosis of IA in patients with hematologic malignancy (HM) and COVID-19. Methods. A single-center prospective study of plasma microbial cfDNA NGS was conducted in a tertiary-care hospital in South Korea. We enrolled adult patients with HM and COVID-19, who suspected IA and performed conventional diagnostic tests for IA. The results of NGS were compared with the diagnosis of IA through conventional methods. IA cases were diagnosed according to EORTC/MSG definitions in patients with HM, and modified AspICU criteria in patients with COVID-19. (Figure 1). Figure 1. Flow chart for the participant selection method used in this study Results. Between March 2021 and January 2022, a total of 33 participants (22 [64.7%] male, median age 66.0 [50.5, 72.0]) were enrolled;19 participants with HM and 15 with COVID-19 were analyzed (Figure1 and Table1). In participants with HM, aspergillus cfDNA was detected in 100% of both proven (1/1) and probable (12/12) IA cases, and 33.3% of both possible (1/3) and no IA (1/3) cases. In participants with COVID-19, 46.2% of probable IA (6/13) showed positive aspergillus cfDNA. Detection rate of aspergillus cfDNA was significantly higher in proven/probable IA cases in participants with HM compared to participants with COVID-19. (100% vs 46.2%, p=0.005) (Figure 2). As shown in Table 2, among proven/probable IA cases, participants with positive aspergillus cfDNA showed significantly higher rate of having uncontrolled hematologic disease, receiving stem cell transplantation and recent chemotherapy. In three participants with HM, non-aspergillus strains confirmed by cfDNA NGS were in accordance with pathogens identified through conventional culture methods. Conclusion. Detection of aspergillus cfDNA showed high concordance in the results of conventional diagnostic methods in proven/probable IA of patients with HM and could be a helpful non-invasive approach to IA diagnosis in those populations.

Risk factors for COVID-19 associated pulmonary aspergillosis (CAPA) in severe COVID-19 and impact of airborne fungal contamination within negative pressure isolation room

Background. COVID-19 increase the risk of invasive pulmonary aspergillosis. However, the risk factors and fungal origin of COVID-19 associated pulmonary aspergillosis (CAPA) is not fully defined yet. We aim to identify the risk factors for CAPA in severe COVID-19 and evaluate association between fungal contamination within the air of negative pressure rooms and diagnosis of CAPAs. Methods. We performed a retrospective case-control study to identify risk factors for CAPA with 420 severe COVID-19 patients from March 2020 to January 2022 who admitted to a tertiary care hospital in South Korea. CAPA was defined with modified AspICU criteria. Control, matched by admission date and severity of COVID-19 at admission, was selected for each case. Air sampling and fungal culture was done on Jan 2022 with a microbial air sampler (MAS-100NT) at 11 spaces in the COVID-19 designated isolation ward including 9 negative pressure isolation rooms (IRs). A cross-sectional comparison between rooms with and without airborne fungal contamination was performed. Results. A total of 420 COVID-19 patients were hospitalized during the study period, and 51 patients were diagnosed with CAPA (prevalence 12.14%, incidence 6.26 per 1000 patient.day). Multivariate analysis showed that older age (odds ratio [OR] 1.051, 95% confidence intervals [CI] 1.006-1.009, p=0.025), mechanical ventilator use (OR 2.692, 95% CI 1.049-6.911, p=0.04), and lymphopenia (OR 4.353, 95% CI 1.727-10.975, p=0.02) were independent risk factors for CAPA. (Table 1, 2) Aspergillus spp. was identified within the air from 7 out of 11 spaces including 6 IRs and 1 doctors' room. (Figure 1). All 6 IRs with positive aspergillus culture were being occupied by patients at least 8 days. Among 6 patients, 3 had already been diagnosed with CAPA whereas the other 3 were not diagnosed with CAPA through the observation period. Among 4 patients in isolation rooms without airborne aspergillus contamination, one patient had been diagnosed as CAPA before air sampling. (Table 3). Conclusion. Association between CAPA and airborne aspergillus contamination within the negative pressure room could not be demonstrated in this study. Rather than environmental factors, patient factors such as older age, ventilator care, and lymphopenia were found to be associated with CAPA diagnosis.

Risk factor and clinical characteristics of pneumothorax and pneumomediastinum in COVID-19: a matched case-control study

Background. During the novel coronavirus SARS-CoV-2 pandemic, a considerable number of pneumothorax and pneumomediastinum associated with COVID-19 have been reported, and the incidence was higher in critically ill patients. Despite using a protective ventilation strategy, barotrauma still occurs in COVID-19 patients with invasive mechanical ventilation. This study aims to identify the risk factors and clinical characteristics of pneumothorax and pneumomediastinum in COVID-19 by a matched case-control study. Methods. This retrospective study enrolled adult patients diagnosed with a COVID-19, admitted to a critical care unit in South Korea from 2020 March 1st to 2022 January 31st. COVID-19 patients with pneumothorax and pneumomediastinum were compared, in a 1 to 2 ratio, to a control group of COVID-19 patients without pneumothorax and pneumomediastinum, matched on age, gender, and worst National Institute of Allergy and Infectious Diseases ordinal scale (NIAID-OS). Conditional logistic regression analysis was performed to assess the risk factors for pneumothorax and pneumomediastinum in COVID-19. Results. A total of 427 patients with COVID-19 were admitted during the study period. Of these patients, 24 patients were diagnosed as pneumothorax or pneumomediastinum. When comparing the characteristics of both groups, body mass index (BMI) was significantly lower in the case group (22.8 kg/m2 and 24.7 kg/m2;P = 0.048). BMI was statistically significant risk factor for barotrauma in univariate conditional logistic regression analysis (Odds ratio (OR), 0.85;Confidence interval (CI), 0.72-0.996;P = 0.044) but not in multivariate analysis. For the patients with invasive mechanical ventilation, the period from symptom onset to intubation was longer in the case-patients (13 and 9.5 days;P = 0.032). Univariate conditional logistic regression analysis showed the statistical significance of the period from symptom onset to intubation (OR, 1.14;CI, 1.006-1.293;P = 0.041). Conclusion. In this case-control study with age, gender, severity matching, lower BMI was associated with the pneumothorax in COVID-19, and delayed application of invasive mechanical ventilation might contribute to this complication.

Clinical significance of antineutrophil cytoplasmic antibody positivity in patients infected with SARS-CoV-2

Background. The Coronavirus Disease 2019 (COVID-19) is well-known for its broad spectrum of immune-related phenotypes similar to those seen in autoimmune or inflammatory diseases. Furthermore, evidence has gradually accumulated that COVID-19 may induce systemic inflammatory manifestations such as multisystem inflammatory syndrome, haemophagocytic syndromes, and systemic vasculitis. Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a small vessel vasculitis characterised by necrotising vasculitis. So far, there have been several case reports regarding AAV occurrence after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which have indicated a triggering potential of SARS-CoV-2 infection for AAV occurrence. This study investigated the rate of ANCA positivity and its clinical significance in COVID-19 patients. Methods. This study included 178 patients infected with SARS-CoV-2 who were enrolled in a cohort of a single center. Myeloperoxidase (MPO)-ANCA and proteinase 3 (PR3)-ANCA from the stored blood sera were measured using the immunoassay kits. Mortality, mechanical ventilator care, and severe infection were assessed as poor outcomes. Severe infection was defined as a medical condition that required a high-flow nasal cannula and/or mechanical ventilator care. The 2022 American College of Rheumatology and the European Alliance of Associations for Rheumatology classification criteria for the three subtypes of AAV were applied only to patients who had MPO-ANCA or PR3-ANCA among the study subjects Results. The detection rate of ANCA positivity was 18.5%: MPO-ANCA and PR3-ANCA were found in 22 (12.4%) and 14 (7.9%) patients. Patients with ANCA positivity exhibited a lower cumulative survival rate than those without, but the difference was not statistically significant (P = 0.057). However, neither MPO-ANCA nor PR3-ANCA affected the three poor outcomes. According to the new criteria, 12 (6.7%) and 21 (11.8%) patients were classified as having granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA) Neither ANCA positivity nor ANCA subtype (MPO-ANCA and PR3-ANCA) positivity had a significant influence on poor outcomes of SARS-CoV-2. ANCA: antineutrophil cytoplasmic antibody;MPO: myeloperoxidase;PR3: proteinase 3;SARS-CoV-2: severe acute respiratory syndrome coronavirus 2. Conclusion. SARS-CoV-2 infection may increase the rate of ANCA positivity, which may not affect poor outcomes but contribute to the classification of GPA and MPA despite uncertain clinical significance.

Social Perception Network Analysis of Educational Communities before and After the Covid-19 Based on Big Data

The purpose of this study is to understand the meaning by utilizing and analyzing big data on the educational community before and after the era of Covid-19, and to suggest the research direction of the future educational community. The keyword ‘Education + Community’ was used to compare big data before February 19, 2020 and after February 19, 2020, when confirmed cases with Covid-19 began to be reported in Republic of Korea. Semantic network analysis was performed from the collected data to the final data that had undergone a refinement process. The big data used in this study consisted of data before February 19, 5,280 data (1,866 KB) and 1314 data (849 KB) after February 19, searched with the keyword ‘educational community’. The analyzed data is a total of 6,594 cases (2715 KB). This study is meaningful in comparing the relationship between keywords related to the educational community in big data before and after the outbreak of Covid-19.Based on the results of this study, practical welfare alternatives and policy alternatives for the future educational community were suggested. © 2021

Absence of neutralizing activity in serum 1 year after successful treatment with antivirals and recovery from MERS in South Korea

We evaluated the neutralizing activity in serum from three patients >1 year after recovery from Middle East respiratory syndrome (MERS) associated with mild pneumonia treated with antivirals during the MERS outbreak in South Korea at 2015. The neutralizing activity in serum was measured by pseudovirus inhibition assays. Three-fold diluted serum of subjects showed only 9.7%, 10.3%, and 2.2% reductions in relative light units. So, significant neutralizing activity was not demonstrated in any sera of three patients with mild pneumonia >1 year after being successfully treated with antiviral agents and recovering from MERS coronavirus infection. FAU - Choi, Jun Yong

Clinical Presentation and Outcomes of Middle East Respiratory Syndrome in the Republic of Korea

Background: From May to July 2015, the Republic of Korea experienced the largest outbreak of Middle East respiratory syndrome (MERS) outside the Arabian Peninsula. A total of 186 patients, including 36 deaths, had been diagnosed with MERS-coronavirus (MERS-CoV) infection as of September 30th, 2015. Materials and Methods: We obtained information of patients who were confirmed to have MERS-CoV infection. MERS-CoV infection was diagnosed using real-time reverse-transcriptase polymerase chain reaction assay. Results: The median age of the patients was 55 years (range, 16 to 86). A total of 55.4% of the patients had one or more coexisting medical conditions. The most common symptom was fever (95.2%). At admission, leukopenia (42.6%), thrombocytopenia (46.6%), and elevation of aspartate aminotransferase (42.7%) were observed. Pneumonia was detected in 68.3% of patients at admission and developed in 80.8% during the disease course. Antiviral agents were used for 74.7% of patients. Mechanical ventilation, extracorporeal membrane oxygenation, and convalescent serum were employed for 24.5%, 7.1%, and 3.8% of patients, respectively. Older age, presence of coexisting medical conditions including diabetes or chronic lung disease, presence of dyspnea, hypotension, and leukocytosis at admission, and the use of mechanical ventilation were revealed to be independent predictors of death. Conclusion: The clinical features of MERS-CoV infection in the Republic of Korea were similar to those of previous outbreaks in the Middle East. However, the overall mortality rate (20.4%) was lower than that in previous reports. Enhanced surveillance and active management of patients during the outbreak may have resulted in improved outcomes. FAU - Choi, Won Suk

Environmental contamination in the isolation rooms of COVID-19 patients with severe pneumonia requiring mechanical ventilation or high-flow oxygen therapy.

BACKGROUND: Identifying the extent of environmental contamination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential for infection control and prevention. The extent of environmental contamination has not been fully investigated in the context of severe coronavirus disease (COVID-19) patients. AIM: To investigate environmental SARS-CoV-2 contamination in the isolation rooms of severe COVID-19 patients requiring mechanical ventilation or high-flow oxygen therapy. METHODS: Environmental swab samples and air samples were collected from the isolation rooms of three COVID-19 patients with severe pneumonia. Patients 1 and 2 received mechanical ventilation with a closed suction system, while patient 3 received high-flow oxygen therapy and non-invasive ventilation. Real-time reverse transcription-polymerase chain reaction (rRT-PCR) was used to detect SARS-CoV-2; viral cultures were performed for samples not negative on rRT-PCR. FINDINGS: Of the 48 swab samples collected in the rooms of patients 1 and 2, only samples from the outside surfaces of the endotracheal tubes tested positive for SARS-CoV-2 by rRT-PCR. However, in patient 3's room, 13 of the 28 environmental samples (fomites, fixed structures, and ventilation exit on the ceiling) showed positive results. Air samples were negative for SARS-CoV-2. Viable viruses were identified on the surface of the endotracheal tube of patient 1 and seven sites in patient 3's room. CONCLUSION: Environmental contamination of SARS-CoV-2 may be a route of viral transmission. However, it might be minimized when patients receive mechanical ventilation with a closed suction system. These findings can provide evidence for guidelines for the safe use of personal protective equipment.