Conversion of medical waste into value-added products using a novel integrated system with tail gas treatment: Process design, optimization, and thermodynamic analysis.

The COVID-19 pandemic has generated substantial medical waste (MW), posing risks to society. Based on widespread MW incineration, this study proposes an integrated system with tail gas treatment to convert MW into value-added products with nearly zero emissions. Herein, steam generators and supercritical CO2 cycles were used to recover energy from MW to produce high-temperature/pressure steam and electricity. A simple power generation cycle achieved a net electricity efficiency of 22.4% through optimization. Thermodynamic analysis revealed that the most energy and exergy loss occurred in incineration. Furthermore, a pressurized reactive distillation column purified the resultant tail gas. The effects of inlet temperature, pressure, liquid/gas ratio, and recycle ratio on the removal and conversion efficiencies of NO2 and SO2 were evaluated. Nearly 100% of the SO2 and 75% of the NO2 generated by the incineration of MW have been converted into their acid forms. Based on the proposed tail gas treatment unit, high-purity CO2 (∼98% purity) was finally obtained.

Transmission Mechanism of Post-COVID-19 Emergency Supply Chain Based on Complex Network: An Improved SIR Model

Since the COVID-19 epidemic swept the world, the emergency supply chain (ESC) has faced serious uncertainty risks. To maintain the stability of the emergency supply, risk prevention and contingency measures must be prepared. In this paper, the authors first obtain the initial risk value of 0.4 using the fuzzy comprehensive evaluation approach and then build an improved SIR model based on a complex network to investigate the risk propagation law of the ESC. The simulation results show that (1) the high number of nodes becomes the initial risk source, the risk propagates faster and the peak value arrives two days earlier on average;(2) the initial infection rate gradually increases from 0.2 to 0.4, 0.6, and 0.8, and the risk spread speed also accelerates;(3) the recovery rate of network nodes increases gradually from 0.1 to 0.2, 0.3, and 0.4, and the influence range of risk propagation decreases inversely;(4) appropriately increasing the deletion rate of network nodes is conducive to improving the stability of the ESC network. Given the above ESC risk propagation law, this paper proposes relevant risk prevention measures and suggests that a risk early warning system of node enterprises should be established in combination with the target immunization strategy. For ESC risk management, the result has significant theoretical and practical implications.

Current State, Development and Future Directions of Medical Waste Valorization

Elevated medical waste has urged the improvement of sustainable medical waste treatments. A bibliometric analysis is initially conducted to investigate scientific development of medical waste management to pinpoint the publication trends, influential articles, journals and countries and study hotspots. Publications on medical waste and its management sharply increased since 2020. The most influential article was written by Klemešet al., and 'Waste Management and Research';is the most productive journal. India, China, the United Kingdom, Iran and Italy have published the most works. The research spotlights have switched from 'human';and 'sustainable development';in 2019 to 'COVID-19';and 'circular economy';in 2021. Since government acts essentially in handling medical waste and controlling disease transmission, rule implementations among the abovementioned countries are summarized to seek gaps between scientific advancement and regulatory frameworks. For accomplishing a circular economy, waste-to-energy technologies (incineration, gasification, pyrolysis, plasma-based treatments, carbonization, hydrogenation, liquefaction, biomethanation, fermentation and esterification) are comprehensively reviewed. Incineration, gasification, pyrolysis and carbonization are relatively feasible methods, their characteristics and limitations are further compared. By holistically reviewing current status of medical waste research, the focal points involved in management at the policy and technical level have been highlighted to find proper routes for medical waste valorization.

The role of SARS-CoV-2 variants of concern in children and adolescents with COVID-19: a systematic review (preprint)

Background: Infections by SARS-CoV-2 variants of concern (VOCs) might affect children and adolescents differently than earlier viral lineages. We aimed to address five questions about SARS-CoV-2 VOC infections in children and adolescents: i) symptoms and severity, ii) risk factors for severe disease, iii) the risk of becoming infected, iv) the risk of transmission and v) long-term consequences following a VOC infection. Methods: We carried out a systematic review. We searched the COVID-19 Open Access Project database up to 1 March 2022 and PubMed up to 9 May 2022 for observational epidemiological studies about alpha, beta, gamma, delta and omicron VOCs among 0 to 18 year olds. We synthesised data for each question descriptively and assessed the risks of bias at the outcome level. Results: We included 53 articles, of which 47% were from high-income countries and none were from low-income countries, according to World Bank categories. Most children with any VOC infection presented with mild disease, with more severe disease being described with the delta or the gamma VOC. Diabetes and obesity were reported as risk factors for severe disease during the whole pandemic period. The risk of becoming infected with a SARS-CoV-2 VOC seemed to increase with age, while in daycare settings the risk of onward transmission of VOCs was higher for younger than older children or at least partially vaccinated adults. Long-term symptoms or signs following an infection with a VOC were described in <5% of children and adolescents. Conclusion: Overall patterns of SARS-CoV-2 VOC infections in children and adolescents are similar to those of earlier lineages. Comparisons between different pandemic periods, countries and age groups should be improved with complete reporting of relevant contextual factors, including VOCs, vaccination status of study participants and the risk of exposure of the population to SARS-CoV-2.

The requirements of nucleic acid test for COVID-19 during public health emergency: Current regulatory in Taiwan, Singapore, and the United States.

In mid-2022, the COVID-19 cases have reached close to 562 million, but its overall infection rate is hard to confirm. Even with effective vaccines, break-through infections with new variants occur, and safe and reliable testing still plays a critical role in isolation of infected individuals and in control of an outbreak of a COVID-19 pandemic. In response to this urgent need, the diagnostic tests for COVID-19 are rapidly evolving and improving these days. The health authorities of many countries issued requirements for detecting SARS-CoV-2 diagnosis tests during the pandemic and have timely access to these tests to ensure safety and effectiveness. In this study, we compared the requirements of EUA in Taiwan, Singapore, and the United States. For the performance evaluations of nucleic acid extraction, inclusivity, limit of detection (LoD), cross-reactivity, interference, cutoff, and stability, the requirements are similar in the three countries. The use of natural clinical specimens is needed for clinical evaluation in Taiwan and the United States. However, carry-over and cross-contamination studies can be exempted in Taiwan and the United States but are required in Singapore. This review outlines requirements and insight to guide the test developers on the development of IVDs. Considering the rapidly evolving viruses and severe pandemic of COVID-19, timely and accurate diagnostic testing is imperative to the management of diseases. As noted above, the performance requirements for SARS-CoV-2 nucleic acid tests are similar between Taiwan, Singapore and the United States. The differences are mainly in two points: the recommended microorganisms for cross-reactivity study, and the specimen requirement for clinical evaluation. This study provides an overview of current requirements of SARS-CoV-2 nucleic acid tests in Taiwan, Singapore, and the United States.

Otologic disease among patients with primary ciliary dyskinesia - an international observational study (preprint)

ABSTRACT Importance Otologic disease is common among people with primary ciliary dyskinesia, yet little is known about its spectrum and severity. Objective We characterized otologic disease among participants with primary ciliary dyskinesia using data from the Ear-Nose-Throat Prospective International Cohort of PCD patients (EPIC-PCD). Design Cross-sectional analysis of baseline cohort data. Setting Twelve specialized primary ciliary dyskinesia centers in 10 countries. Participants We prospectively included children and adults with primary ciliary dyskinesia diagnoses, routine ENT examinations, and completed symptom questionnaires at the same visit or within 2 weeks. Exposures Potential risk factors associated with increased risk of ear disease. Main outcomes and measures We describe the prevalence and characteristics of patient-reported otologic symptoms and findings from otologic examinations; we identify potential factors associated with increased risk of ear inflammation and hearing impairment. Results We included 397 (211 males) participants with median age 15 (range 0–73). A total of 204 (51%) reported ear pain, 110 (28%) ear discharge, and 183 (46%) hearing problems. Adults reported ear pain and hearing problems more frequently when compared with children. Otitis media with effusion—usually bilateral—from otoscopy was most common among 121 (32%) of 384 participants. Retracted tympanic membrane and tympanic sclerosis were more commonly seen among adults. Tympanometry was performed on 216 participants and showed pathologic type B results for 114 (53%). Audiometry was performed on 273 participants and showed hearing impairment in at least 1 ear, most commonly mild. Season of visit was the strongest risk factor for problems related to ear inflammation (autumn compared with spring odds ratio, 95% confidence interval: 2.4, 1.5–3.8) and age 30 and older of hearing impairment (age 41–50 compared with age 10 years and younger odds ratio, 95% confidence interval: 3.3, 1.1–9.9). Conclusion and relevance Many people with primary ciliary dyskinesia suffer from ear problems yet frequency varies, highlighting disease expression differences and possible clinical phenotypes. Understanding differences in otologic disease expression and progression during lifetime may inform clinical decisions about follow-up and medical care. We recommend multidisciplinary primary ciliary dyskinesia management includes regular otologic assessments for all ages even without specific complaints. Key Points Question What are the characteristics of otologic disease among patients with primary ciliary dyskinesia (PCD)? Findings Baseline data from a large multicenter cohort of patients with PCD showed frequent reports of ear pain and reduced hearing with age as the main factor associated with hearing impairment. Otitis media with effusion was the most common otoscopic finding; adults often presented with tympanic sclerosis following history of previous ear infections. Meaning Since otologic disease is an important yet underreported part of PCD’s clinical expression, we recommend otologic assessments for all age groups as part of regular clinical follow-up.

Accurate virus identification with interpretable Raman signatures by machine learning.

Rapid identification of newly emerging or circulating viruses is an important first step toward managing the public health response to potential outbreaks. A portable virus capture device, coupled with label-free Raman spectroscopy, holds the promise of fast detection by rapidly obtaining the Raman signature of a virus followed by a machine learning (ML) approach applied to recognize the virus based on its Raman spectrum, which is used as a fingerprint. We present such an ML approach for analyzing Raman spectra of human and avian viruses. A convolutional neural network (CNN) classifier specifically designed for spectral data achieves very high accuracy for a variety of virus type or subtype identification tasks. In particular, it achieves 99% accuracy for classifying influenza virus type A versus type B, 96% accuracy for classifying four subtypes of influenza A, 95% accuracy for differentiating enveloped and nonenveloped viruses, and 99% accuracy for differentiating avian coronavirus (infectious bronchitis virus [IBV]) from other avian viruses. Furthermore, interpretation of neural net responses in the trained CNN model using a full-gradient algorithm highlights Raman spectral ranges that are most important to virus identification. By correlating ML-selected salient Raman ranges with the signature ranges of known biomolecules and chemical functional groups­for example, amide, amino acid, and carboxylic acid­we verify that our ML model effectively recognizes the Raman signatures of proteins, lipids, and other vital functional groups present in different viruses and uses a weighted combination of these signatures to identify viruses.

ERS International Congress 2021: highlights from the Paediatric Assembly.

In this review, Early Career Members of the European Respiratory Society (ERS) and the Chairs of the ERS Assembly 7: Paediatrics present the highlights in paediatric respiratory medicine from the ERS International Congress 2021. The eight scientific Groups of this Assembly cover respiratory physiology and sleep, asthma and allergy, cystic fibrosis (CF), respiratory infection and immunology, neonatology and intensive care, respiratory epidemiology, bronchology, and lung and airway development. We here describe new developments in lung function testing and sleep-disordered breathing diagnosis, early life exposures affecting pulmonary function in children and effect of COVID-19 on sleep and lung function. In paediatric asthma, we present the important role of the exposome in asthma development, and how biologics can provide better outcomes. We discuss new methods to assess distal airways in children with CF, as some details remain blind when using the lung clearance index. Moreover, we summarise the new ERS guidelines for bronchiectasis management in children and adolescents. We present interventions to reduce morbidity and monitor pulmonary function in newborns at risk of bronchopulmonary dysplasia and long-term chronic respiratory morbidity of this disease. In respiratory epidemiology, we characterise primary ciliary dyskinesia, identify early life determinants of respiratory health and describe the effect of COVID-19 preventive measures on respiratory symptoms. Also, we describe the epidemiology of interstitial lung diseases, possible consequences of tracheomalacia and a classification of diffuse alveolar haemorrhage in children. Finally, we highlight that the characterisation of genes and pathways involved in the development of a disease is essential to identify new biomarkers and therapeutic targets.

Accurate Virus Identification with Interpretable Raman Signatures by Machine Learning (preprint)

Rapid identification of newly emerging or circulating viruses is an important first step toward managing the public health response to potential outbreaks. A portable virus capture device coupled with label-free Raman Spectroscopy holds the promise of fast detection by rapidly obtaining the Raman signature of a virus followed by a machine learning approach applied to recognize the virus based on its Raman spectrum, which is used as a fingerprint. We present such a machine learning approach for analyzing Raman spectra of human and avian viruses. A Convolutional Neural Network (CNN) classifier specifically designed for spectral data achieves very high accuracy for a variety of virus type or subtype identification tasks. In particular, it achieves 99% accuracy for classifying influenza virus type A vs. type B, 96% accuracy for classifying four subtypes of influenza A, 95% accuracy for differentiating enveloped and non-enveloped viruses, and 99% accuracy for differentiating avian coronavirus (infectious bronchitis virus, IBV) from other avian viruses. Furthermore, interpretation of neural net responses in the trained CNN model using a full-gradient algorithm highlights Raman spectral ranges that are most important to virus identification. By correlating ML-selected salient Raman ranges with the signature ranges of known biomolecules and chemical functional groups (for example, amide, amino acid, carboxylic acid), we verify that our ML model effectively recognizes the Raman signatures of proteins, lipids and other vital functional groups present in different viruses and uses a weighted combination of these signatures to identify viruses.

COVID-19 Vaccinations: Perceptions and Behaviours in People with Primary Ciliary Dyskinesia.

Primary ciliary dyskinesia (PCD) is a rare genetic disease that causes recurrent respiratory infections. People with PCD may be at higher risk of severe coronavirus disease 2019 (COVID-19), and therefore vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is important. We studied vaccination willingness, speed of vaccination uptake, side effects, and changes in social contact behaviour after vaccination in people with PCD. We used data from COVID-PCD, an international participatory cohort study. A COVID-19 vaccination questionnaire was emailed to participants in May 2021 and 423 participants from 31 countries replied (median age: 30 years, range 1-85 years; 261 (62%) female). Vaccination uptake and willingness were high, with 273 of 287 adults (96%) being vaccinated or willing to be in June 2021; only 4% were hesitant. The most common reason for hesitancy was fear of side effects, reported by 88%. Mild side effects were common, but no participant reported severe side effects. Half of the participants changed their social behaviour after vaccination by seeing friends and family more often. The high vaccination willingness in the study population might reflect the extraordinary effort taken by PCD support groups to inform people about COVID-19 vaccination. Clear and specific information and involvement of representatives is important for high vaccine uptake.

The high diversity of SARS-CoV-2-related coronaviruses in pangolins alerts potential ecological risks.

Understanding the zoonotic origin and evolution history of SARS-CoV-2 will provide critical insights for alerting and preventing future outbreaks. A significant gap remains for the possible role of pangolins as a reservoir of SARS-CoV-2 related coronaviruses (SC2r-CoVs). Here, we screened SC2r-CoVs in 172 samples from 163 pangolin individuals of four species, and detected positive signals in muscles of four Manis javanica and, for the first time, one M. pentadactyla. Phylogeographic analysis of pangolin mitochondrial DNA traced their origins from Southeast Asia. Using in-solution hybridization capture sequencing, we assembled a partial pangolin SC2r-CoV (pangolin-CoV) genome sequence of 22 895 bp (MP20) from the M. pentadactyla sample. Phylogenetic analyses revealed MP20 was very closely related to pangolin-CoVs that were identified in M. javanica seized by Guangxi Customs. A genetic contribution of bat coronavirus to pangolin-CoVs via recombination was indicated. Our analysis revealed that the genetic diversity of pangolin-CoVs is substantially higher than previously anticipated. Given the potential infectivity of pangolin-CoVs, the high genetic diversity of pangolin-CoVs alerts the ecological risk of zoonotic evolution and transmission of pathogenic SC2r-CoVs.

COVID-19 vaccinations: perceptions and behaviours in people with primary ciliary dyskinesia (preprint)

Primary ciliary dyskinesia (PCD) is a rare genetic disease that causes recurrent respiratory infections. People with PCD may be at high risk of severe COVID-19 and vaccination against SARS-CoV-2 is therefore important. We studied vaccination willingness, speed of vaccination uptake, side effects, and changes in social contact behavior after vaccination in people with PCD. We used data from COVID-PCD, an international participatory cohort study. A questionnaire was e-mailed to participants in May 2021 that asked about COVID-19 vaccinations. 423 participants from 31 countries replied (median age: 30 years; 261 (62%) female). Vaccination uptake and willingness was high with 273 of 287 adults (96%) being vaccinated or willing to be in June 2021; only 4% were hesitant. The most common reasons for hesitancy were fear of side effects (reported by 88%). Mild side effects were common but no participant reported severe side effects. Half of participants changed their social contact behaviour after vaccination by seeing friends and family more often. The high vaccination willingness in the study population might reflect the extraordinary effort taken by PCD support groups to inform people about COVID-19 vaccination. Clear and specific public information and involvement of representatives is important for high vaccine uptake.

A public survey of traditional, complementary and integrative medicine use during the COVID-19 outbreak in Hong Kong.

BACKGROUND: During COVID-19, the public actively sought non-pharmacological and self-management approaches to prevent infection. Little is known on the use of traditional, complementary and integrative medicine (TCIM) by the public as preventive measures. This study investigated the prevalence and patterns of TCIM use during the pandemic, and identified factors associated with its use among the general population in Hong Kong. METHODS: An online cross-sectional survey was conducted from November to December 2020. The survey solicited information on the respondents' sociodemographic characteristics, risk perception of the pandemic, and use of TCIM before and during the pandemic. Logistic regression analysis was conducted to determine predictors of TCIM use. RESULTS: In total, 632 responses (completion rate = 88.1%) were analyzed. TCIM was used by 44.0% of respondents during the pandemic. The most popular forms of TCIM were vitamins or other dietary supplements (n = 160, 25.3%) and Chinese herbal medicine (n = 122, 19.3%) during the pandemic. The most frequently reported indication was strengthening the immune system, especially for vitamins or other dietary supplements (n = 142/160, 88.8%). Respondents who reported using TCIM were more likely to be female (adjusted odds ratio [aOR] = 1.82, 95% confidence interval [CI] = 1.29-2.59), had higher education attainment (aOR = 2.21, 95% CI = 1.39-3.59), and older-aged (age >55 years: aOR = 1.77, 95% CI = 1.04-3.02). Respondents who resided in districts with moderate to high number of confirmed COVID-19 cases (aOR = 1.60, 95% CI = 1.07-2.42) and had a higher level of risk perception (aOR = 1.04, 95% CI = 1.01-1.07) were also more likely to use TCIM. CONCLUSION: TCIM was used commonly in Hong Kong during the COVID-19 pandemic. While vaccination and social distancing remain the mainstay of controlling the pandemic, professional bodies should proactively consider public preferences and provide information regarding the effectiveness and safety of TCIM for COVID-19 prevention and treatment.

Accurate Virus Identification with Interpretable Raman Signatures by Machine Learning (preprint)

Rapid identification of newly emerging or circulating viruses is an important first step toward managing the public health response to potential outbreaks. A portable virus capture device coupled with label-free Raman Spectroscopy holds the promise of fast detection by rapidly obtaining the Raman signature of a virus followed by a machine learning approach applied to recognize the virus based on its Raman spectrum. In this paper, we present a machine learning analysis on Raman spectra of human and avian viruses. A Convolutional Neural Network (CNN) classifier specifically designed for spectral data achieves very high accuracy for a variety of virus type or subtype identification tasks. In particular, it achieves 99% accuracy for classifying influenza virus type A vs. type B, 96% accuracy for classifying four subtypes of influenza A, 95% accuracy for differentiating enveloped and non-enveloped viruses, and 99% for differentiating avian coronavirus (infectious bronchitis virus, IBV) from other avian viruses. Furthermore, interpretation of neural net responses in the trained CNN model using a full-gradient algorithm highlights Raman spectral ranges that are most important to virus identification. By correlating ML-selected salient Raman ranges with the signature ranges of known biomolecules and chemical functional groups (e.g. amide, amino acid, carboxylic acid) we verify that our ML model effectively recognizes the Raman signatures of proteins, lipids and other vital functional groups present in different viruses and uses a weighted combination of these signatures to identify viruses. The accurate and interpretable machine learning model developed for Raman virus identification presents promising potential in a real-time virus detection system. Significance Statement A portable micro-fluidic platform for virus capture promises rapid enrichment and label-free optical identification of viruses by Raman spectroscopy. A large Raman dataset collected on a variety of viruses enables the training of machine learning (ML) models capable of highly accurate and sensitive virus identification. The trained ML models can then be integrated with the portable device to provide real-time virus detection and identification capability. We validate this conceptual framework by presenting highly accurate virus type and subtype identification results using a convolutional neural network to classify Raman spectra of viruses.

COVID-PCD: a participatory research study on the impact of COVID-19 in people with primary ciliary dyskinesia.

COVID-PCD is a participatory study initiated by people with primary ciliary dyskinesia (PCD) who have an essential vote in all stages of the research from the design of the study to the recruitment of participants, and interpretation and communication of the study results. COVID-PCD aims to collect epidemiological data in real-time from people with PCD throughout the pandemic to describe incidence of coronavirus disease 2019 (COVID-19), symptoms and course of disease; identify risk factors for prognosis; and assess experiences, wishes and needs. The study is advertised through patient support groups and participants register online on the study website (www.covid19pcd.ispm.ch). The study invites persons of any age from anywhere in the world with a suspected or confirmed PCD. A baseline questionnaire assesses details on PCD diagnosis, habitual symptoms and COVID-19 episodes that occurred before study entry. Afterwards, participants receive a weekly follow-up questionnaire with questions on incident severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections, current symptoms, social contact behaviour and physical activity. Occasional thematic questionnaires are sent out focussing on emerging questions of interest chosen by people with PCD. In case of hospitalisation, patients or family members are asked to obtain a hospital report. Results are continuously analysed and summaries put online. The study started recruitment on April 30, 2020, and 556 people with PCD completed the baseline questionnaire by November 2, 2020. The COVID-PCD study is a participatory study that follows people with PCD during the COVID-19 pandemic, helps to empower affected persons, and serves as a platform for communication between patients, physicians and researchers.

COVID-PCD a participatory research study on the impact of COVID-19 in people with Primary Ciliary Dyskinesia (preprint)

Introduction COVID-PCD is a participatory study initiated by people with PCD who have an essential vote in all stages of the research from the design of the study to the recruitment of participants, and interpretation and communication of the study results. COVID-PCD aims to collect epidemiological data in real time from people with PCD throughout the pandemic to describe incidence of COVID-19, symptoms, and course of disease; identify risk factors for prognosis; and assess experiences, wishes, and needs. Methods The study is advertised through patient support groups and participants register online on the study website (www.covid19pcd.ispm.ch). The study invites persons of any age from anywhere in the world with a suspected or confirmed PCD. A baseline questionnaire assesses details on PCD diagnosis, habitual symptoms, and COVID-19 episodes that occurred before study entry. Afterwards, participants receive a weekly follow-up questionnaire with questions on incident SARS-CoV-2 infections, current symptoms, social contact behaviour, and physical activity. Occasional thematic questionnaires are sent out focusing on emerging questions of interest chosen by people with PCD. In case of hospitalisation, patients or family members are asked to obtain a hospital report. Results are continuously analysed and summaries put online. Conclusion The study started recruitment on April 30, 2020, and 556 people with PCD completed the baseline questionnaire by November 2, 2020. The COVID-PCD study is a participatory study that follows people with PCD during the COVID-19 pandemic, helps to empower affected persons, and serves as a platform for communication between patients, physicians, and researchers.