Factors associated with an increased risk of SARS-CoV-2 infection in healthcare workers in aerosol-generating disciplines.

BACKGROUND: Healthcare workers (HCWs) are at a high risk of SARS-CoV-2 infection due to exposure to potentially infectious material, especially during aerosol-generating procedures (AGP). We aimed to investigate risk factors for SARS-CoV-2 infection among HCWs in medical disciplines with AGP. METHODS: A nationwide questionnaire-based study in private practices and hospital settings was conducted between 12/16/2020 and 01/24/2021. Data on SARS-CoV-2 infections among HCWs and potential risk factors of infection were investigated. RESULTS: 2070 healthcare facilities with 25113 employees were included in the study. The overall infection rate among HCWs was 4.7%. Multivariate analysis showed that regions with higher incidence rates had a significantly increased risk of infection. Furthermore, hospital setting and HCWs in gastrointestinal endoscopy (GIE) had more than double the risk of infection (OR 2.63; 95% CI 2.50-2.82, p<0.01 and OR 2.35; 95% CI 2.25-2.50, p<0.01). For medical facilities who treated confirmed SARS-CoV-2 cases, there was a tendency towards higher risk of infection (OR 1.39; 95% CI 1.11-1.63, p=0.068). CONCLUSION: Both factors within and outside medical facilities appear to be associated with an increased risk of infection among HCWs. Therefore, GIE and healthcare delivery setting were related to increased infection rates. Regions with higher SARS-CoV-2 incidence rates were also significantly associated with increased risk of infection.

[Impact of Covid 19 on endoscopy in Germany]. / Ein Jahr Covid-19: Testung, Verwendung von Schutzausrüstung und Auswirkungen auf die Gastrointestinale Endoskopie in Deutschland.

BACKGROUND: Practices and hospitals are facing great challenges in coping with the COVID-19-pandemic. So far, data on the impact of the pandemic on gastroenterological facilities are lacking, especially on a temporal course. A database is lacking, especially for the outpatient care sector. University Hospital of Augsburg was commissioned to generate data on this as a part of the collaborative project B-FAST of the Network of University Medicine (NUM). METHODS: Gastroenterological institutions nationwide were surveyed by an online questionnaire. Recruitment was carried out via the German Society of Gastroenterology, Digestive and Metabolic Diseases (DGVS) and the Professional Association of Gastroenterologists in Private Practice (bng). This manuscript provides an overview of data on the use of protective equipment, pre-interventional testing of patients, staff screening and economic impact over the course of the pandemic. RESULTS: 429 facilities answered the questionnaire. Practices tested their patients pre-interventionally significantly less often than clinics (7.8% vs. 82.6%). In clinics, inpatients (93.1%) were tested significantly more often than outpatients (72.2%). The use of personal protective equipment (PPE) increased significantly during the pandemic. It was shown that over 70% of facilities screened their staff for SARS-CoV-2 without cause. Clinics cancelled elective procedures significantly more often than practices in quarter 4/2020. Procedures and turnover decreased in 2020 compared to the previous year. However, fewer facilities were affected by a loss of revenue than expected in previous studies. CONCLUSION: Our data demonstrate the variable implementation of pre-interventional SARS-CoV-2 testing in outpatient and inpatient care. The use of adequate PPE and staff screening increased during the pandemic.

[Screening gastroscopy in Germany - first results of the pilot phase of the Prä-GIT study]. / Vorsorgegastroskopie in Deutschland ­ erste Ergebnisse der Pilotphase der Prä-GIT-Studie.

The primary aim of the Prä-GIT study is to collect information on the prevalence and course of precancerous and early malignant lesions in the upper GIT (uGIT) as well as risk factors associated with these lesions in asymptomatic individuals. Study participants presenting for a screening colonoscopy will undergo an additional endoscopic examination of the uGIT in the same session. 5000 participants in 30 endoscopy clinics in Bayern will be included. The pilot study presented here was performed to test the main study protocol as well as the acceptance of an additional uGIT endoscopic examination. METHODS: Three endoscopy clinics in Bayern took part in the three-month pilot study between October and December 2018. Patients presenting for a screening colonoscopy in these clinics were offered an additional endoscopic examination of the uGIT which was performed according to a standard operating procedure (SOP). Furthermore, data on dietary habits and lifestyle, as well as biological samples, were collected. RESULTS: 52 participants were included in three clinics in Altötting, Augsburg and Regensburg. The average age was 63.4 years. The average time spent per uGIT endoscopy was 11 minutes. No complications occurred. One participant showed a polyp of the recessus piriformis. Refluxesophagitis was seen in 21 participants, four participants had Barrett's esophagus with histological evidence of low-grade dysplasia in one patient, and an esophageal polyp with low-grade dysplasia was seen in one participant. Helicobacter-pylori gastritis was documented in 12 participants. Corpus-dominant atrophy was described in one participant, while a duodenal adenoma with low-grade dysplasia was seen in two participants. 100 % and 89 % of study participants gave a blood or a stool sample, respectively. All participants answered the questionnaire on dietary and lifestyle habits. CONCLUSION: The Prä-GIT study was designed to generate a database for premalignant and early cancerous lesions of the uGIT in Germany in asymptomatic individuals presenting for a regular screening colonoscopy. The current pilot study has delivered important insights into the feasibility of the main study protocol. Additionally, the pilot study has shown a high rate of acceptance of an additional uGIT examination in this study population.

Potential of a novel brine-struvite-based growth medium for sustainable biomass and phycocyanin production by Arthrospira platensis.

Nutrient recovery is crucial for sustainability as it helps to recycle valuable resources, reduce environmental pollution, and promote the efficient use of natural materials in various agricultural and industrial processes. The present study investigated the impact of using brine and struvite as sustainable nutrient sources on the growth and c-phycocyanin (C-PC) production by the cyanobacterium Arthrospira platensis. Three modified growth media were compared to the standard SAG-spirul medium under yellow-white light [YLT], and blue-white light [BLT]. In the modified medium BSI, a struvite solution was utilized to replace dipotassium phosphate, while diluted brine was used to replace NaCl and de-ionized H2O. For BSII, struvite and brine were used as in BSI, with elimination of the micronutrient from the solution. In BSIII, no other nutrient sources than bicarbonate-buffer were used in addition to struvite and brine. For each medium, A. platensis was cultivated and incubated under YLT or BLT till the stationary phase. The results showed that the combinations of brine and struvite did not have any significant negative impact on the growth rates in BSIII. However, adding struvite as a phosphorus source boosted C-PC production just as effectively as YLT, with boosting biomass yield, unlike when only BLT was used. In conclusion, the brine/struvite-based media resulted in high biomass productivity with higher C-PC yields, making it an ideal growth medium for commercial sustainable C-PC production.

SARS-CoV-2 Vaccination Rate and SARS-CoV-2 Infection of Health Care Workers in Aerosol-Generating Medical Disciplines.

Healthcare workers (HCW) who perform aerosol-generating procedures (AGP) are at high risk of SARS-CoV-2 infection. Data on infection rates and vaccination are limited. A nationwide, cross-sectional study focusing on AGP-related specialties was conducted between 3 May 2021 and 14 June 2021. Vaccination rates among HCW, perception of infection risk, and infection rates were analyzed, focusing on the comparison of gastrointestinal endoscopy (GIE) and other AGP-related specialties (NON-GIE), from the beginning of the pandemic until the time point of the study. Infections rates among HCW developed similarly to the general population during the course of the pandemic, however, with significantly higher infections rates among the GIE specialty. The perceived risk of infection was distributed similarly among HCW in GIE and NON-GIE (91.7%, CI: 88.6−94.4 vs. 85.8%, CI: 82.4−89.0; p < 0.01) with strongest perceived threats posed by AGPs (90.8%) and close patient contact (70.1%). The very high vaccination rate (100−80%) among physicians was reported at 83.5%, being significantly more frequently reported than among nurses (56.4%, p < 0.01). GIE had more often stated very high vaccination rate compared with NON-GIE (76.1% vs. 65.3%, p < 0.01). A significantly higher rate of GIE was reported to have fewer concerns regarding infection risk after vaccination than NON-GIE (92.0% vs. 80.3%, p < 0.01).

Computer-aided detection of colorectal polyps using a newly generated deep convolutional neural network: from development to first clinical experience.

AIM: The use of artificial intelligence represents an objective approach to increase endoscopist's adenoma detection rate (ADR) and limit interoperator variability. In this study, we evaluated a newly developed deep convolutional neural network (DCNN) for automated detection of colorectal polyps ex vivo as well as in a first in-human trial. METHODS: For training of the DCNN, 116 529 colonoscopy images from 278 patients with 788 different polyps were collected. A subset of 10 467 images containing 504 different polyps were manually annotated and treated as the gold standard. An independent set of 45 videos consisting of 15 534 single frames was used for ex vivo performance testing. In vivo real-time detection of colorectal polyps during routine colonoscopy by the DCNN was tested in 42 patients in a back-to-back approach. RESULTS: When analyzing the test set of 15 534 single frames, the DCNN's sensitivity and specificity for polyp detection and localization within the frame was 90% and 80%, respectively, with an area under the curve of 0.92. In vivo, baseline polyp detection rate and ADR were 38% and 26% and significantly increased to 50% (P = 0.023) and 36% (P = 0.044), respectively, with the use of the DCNN. Of the 13 additionally with the DCNN detected lesions, the majority were diminutive and flat, among them three sessile serrated adenomas. CONCLUSION: This newly developed DCNN enables highly sensitive automated detection of colorectal polyps both ex vivo and during first in-human clinical testing and could potentially increase the detection of colorectal polyps during colonoscopy.