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Liu M, Liu J, Cao Q, Li X, Liu S, Ji S, Lin CH, Wei D, Shen X, Long Z, Chen Q. Evaluation of different air distribution systems in a commercial airliner cabin in terms of comfort and COVID-19 infection risk. BUILDING AND ENVIRONMENT 2022; 208:108590. [PMID: 34812218 PMCID: PMC8599143 DOI: 10.1016/j.buildenv.2021.108590] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 10/09/2021] [Accepted: 11/15/2021] [Indexed: 05/24/2023]
Abstract
The air distribution system in an airliner plays a key role in maintaining a comfortable and healthy environment in the aircraft cabin. To evaluate the performance of a novel displacement ventilation (DV) system and a traditional mixing ventilation (MV) system in an airliner cabin, this study conducted experiments and simulations in a seven-row cabin mockup. This investigation used ultrasonic anemometers and T-thermocouples to measure the air velocity, temperature and distribution of 1 μm and 5 μm particles. Simulation verifications were performed for these operating conditions, and additional scenarios with different occurrence source locations were also simulated. This study combined the Wells-Riley equation with a real case based on a COVID-19 outbreak among passengers on a long-distance bus to obtain the COVID-19 quanta value. Through an evaluation of the airflow organization, thermal comfort, and risk of COVID-19 infection, the two ventilation systems were compared. This investigation found that polydisperse particles should be used to calculate the risk of infection in airliner cabins. In addition, at the beginning of the pandemic, the infection risk with DV was lower than that with MV. In the middle and late stages of the epidemic, the infection risk with MV can be reduced when passengers wear masks, leading to an infection risk approximately equal to that of DV.
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Motamedi H, Shirzadi M, Tominaga Y, Mirzaei PA. CFD modeling of airborne pathogen transmission of COVID-19 in confined spaces under different ventilation strategies. SUSTAINABLE CITIES AND SOCIETY 2022; 76:103397. [PMID: 34631393 PMCID: PMC8487408 DOI: 10.1016/j.scs.2021.103397] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/21/2021] [Accepted: 09/23/2021] [Indexed: 05/18/2023]
Abstract
Airborne transmission is an important route of spread of viral diseases (e.g., COVID-19) inside the confined spaces. In this respect, computational fluid dynamics (CFD) emerged as a reliable and fast tool to understand the complex flow patterns in such spaces. Most of the recent studies, nonetheless, focused on the spatial distribution of airborne pathogens to identify the infection probability without considering the exposure time. This research proposes a framework to evaluate the infection probability related to both spatial and temporal parameters. A validated Eulerian-Lagrangian CFD model of exhaled droplets is first developed and then evaluated with an office case study impacted by different ventilation strategies (i.e., cross- (CV), single- (SV), mechanical- (MV) and no-ventilation (NV)). CFD results were analyzed in a bespoke code to calculate the tempo-spatial distribution of accumulated airborne pathogens. Furthermore, two indices of local and general infection risks were used to evaluate the infection probability of the ventilation scenarios. The results suggest that SV has the highest infection probability while SV and NO result in higher dispersions of airborne pathogens inside the room. Eventually, the time history of indices reveals that the efficiency of CV and MV can be poor in certain regions of the room.
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Zhang CM, Xu PC, Du WW, Wang XC. Exposure parameters and health risk of Cryptosporidium and Giardia in the recreational water activities for urban residents in China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:1573-1583. [PMID: 34363153 DOI: 10.1007/s11356-021-15463-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Accepted: 07/12/2021] [Indexed: 06/13/2023]
Abstract
Knowledge gaps in the exposure parameters for recreational water activities make quantitative risk assessment related to water recreation difficult. Therefore, the annual exposure frequency and single exposure duration for the recreational water activities of residents from ten cities in the North and South of China were investigated. Questionnaire interviews were carried on recreational water activities comprising swimming (SW), boating (BA), playing in interactive fountains (PF), and watching fountains (WF). Quantitative microbial risk assessment for the exposure of urban residents to Cryptosporidium and Giardia was also performed. For the four recreational water activities, the participation rates of urban residents in SW and WF were higher than the others. For SW and BA, the mean annual exposure frequency and single exposure duration for males were significantly higher than those for females. PF and WF showed the opposite. The annual exposure frequency for above 35-year-old residents was higher than that for young residents (18-35 years). However, the single exposure duration for young residents was highest in SW, BA, and PF. The mean annual exposure frequency and single exposure duration for North China residents were higher than those for South China residents in all recreational water activities, except for SW. Overall, the annual exposure frequency and single exposure duration in recreational water activities for all urban residents followed a lognormal distribution. In the four recreational water activities, the total annual infection risk of male exposure to Cryptosporidium was 1.0 × 10-2, with the confidence intervals between 95 and 5% of [4.3 × 10-4, 3.7 × 10-2], whereas that for females was 6.8 × 10-3 and [4.2 × 10-4, 2.4 × 10-2]. Also, the annual infection risk of males to Giardia was 8.8 × 10-3 and [5.1×10-4, 3.2×10-2], and that of females was 5.3 × 10-3 and [4.0 × 10-4, 1.8 × 10-2]. These results demonstrated that SW and PF made the highest contribution to the total annual infection risk. Sensitivity analysis highlighted that the characterization of exposure parameters plays a critical role in health risk assessment, which may provide a scientific basis for recreational water quality standards formulation.
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Li H, Shankar SN, Witanachchi CT, Lednicky JA, Loeb JC, Alam MM, Fan ZH, Mohamed K, Boyette JA, Eiguren-Fernandez A, Wu CY. Environmental Surveillance for SARS-CoV-2 in Two Restaurants from a Mid-scale City that Followed U.S. CDC Reopening Guidance. AEROSOL AND AIR QUALITY RESEARCH 2022; 22:210304. [PMID: 35024044 PMCID: PMC8752097 DOI: 10.4209/aaqr.210304] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Since mask use and physical distancing are difficult to maintain when people dine indoors, restaurants are perceived as high risk for acquiring COVID-19. The air and environmental surfaces in two restaurants in a mid-scale city located in north central Florida that followed the Centers for Disease Control and Prevention (CDC) reopening guidance were sampled three times from July 2020 to February 2021. Sixteen air samples were collected for 2 hours using air samplers, and 20 surface samples by using moistened swabs. The samples were analyzed by real-time reverse transcriptase-polymerase chain reaction (RT-PCR) for the presence of SARS-CoV-2 genomic RNA. A total of ~550 patrons dined in the restaurants during our samplings. SARS-CoV-2 genomic RNA was not detected in any of the air samples. One of the 20 surface samples (5%) was positive. That sample had been collected from a plastic tablecloth immediately after guests left the restaurant. Virus was not isolated in cell cultures inoculated with aliquots of the RT-PCR-positive sample. The likelihood that patrons and staff acquire SARS-CoV-2 infections may be low in restaurants in a mid-scale city that adopt CDC restaurant reopening guidelines, such as operation at 50% capacity so that tables can be spaced at least 6 feet apart, establishment of adequate mechanical ventilation, use of a face covering except while eating or drinking, and implementation of disinfection measures.
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Albrecht K, Poddubnyy D, Leipe J, Sewerin P, Iking-Konert C, Scholz R, Krüger K. [Perioperative management of treatment of patients with inflammatory rheumatic diseases : Updated recommendations of the German Society of Rheumatology]. Z Rheumatol 2021; 81:212-224. [PMID: 34928422 DOI: 10.1007/s00393-021-01140-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/31/2021] [Indexed: 12/28/2022]
Abstract
BACKGROUND Prior to surgical interventions physicians and patients with inflammatory rheumatic diseases remain concerned about interrupting or continuing anti-inflammatory medication. For this reason, the German Society for Rheumatology has updated its recommendations from 2014. METHODS After a systematic literature search including publications up to 31 August 2021, the recommendations on the use of of glucocorticoids, conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and biologics (bDMARDs) were revised and recommendations on newer drugs and targeted synthetic (ts)DMARDs were added. RESULTS The glucocorticoid dose should be reduced to as low as possible 2-3 months before elective surgery (in any case <10 mg/day) but should be kept stable 1-2 weeks before and on the day of surgery. In many cases csDMARDs can be continued, exceptions being a reduction of high methotrexate doses to ≤15 mg/week and wash-out of leflunomide if there is a high risk of infection. Azathioprine, mycophenolate and ciclosporin should be paused 1-2 days prior to surgery. Under bDMARDs surgery can be scheduled for the end of each treatment interval. For major interventions Janus kinase (JAK) inhibitors should be paused for 3-4 days. Apremilast can be continued. If interruption is necessary, treatment should be restarted as soon as possible for all substances, depending on wound healing. CONCLUSION Whether bDMARDs increase the perioperative risk of infection and the benefits and risks of discontinuation remain unclear based on the currently available evidence. To minimize the risk of a disease relapse under longer treatment pauses, in the updated recommendations the perioperative interruption of bDMARDs was reduced from at least two half-lives to one treatment interval.
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Murakami M, Miura F, Kitajima M, Fujii K, Yasutaka T, Iwasaki Y, Ono K, Shimazu Y, Sorano S, Okuda T, Ozaki A, Katayama K, Nishikawa Y, Kobashi Y, Sawano T, Abe T, Saito MM, Tsubokura M, Naito W, Imoto S. COVID-19 risk assessment at the opening ceremony of the Tokyo 2020 Olympic Games. MICROBIAL RISK ANALYSIS 2021; 19:100162. [PMID: 33778137 PMCID: PMC7981581 DOI: 10.1016/j.mran.2021.100162] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 02/22/2021] [Accepted: 03/09/2021] [Indexed: 05/09/2023]
Abstract
The 2020 Olympic/Paralympic Games have been postponed to 2021, due to the COVID-19 pandemic. We developed a model that integrated source-environment-receptor pathways to evaluate how preventive efforts can reduce the infection risk among spectators at the opening ceremony of Tokyo Olympic Games. We simulated viral loads of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emitted from infectors through talking/coughing/sneezing and modeled temporal environmental behaviors, including virus inactivation and transfer. We performed Monte Carlo simulations to estimate the expected number of newly infected individuals with and without preventive measures, yielding the crude probability of a spectator being an infector among the 60,000 people expected to attend the opening ceremony. Two indicators, i.e., the expected number of newly infected individuals and the newly infected individuals per infector entry, were proposed to demonstrate the extent of achievable infection risk reduction levels by implementing possible preventive measures. A no-prevention scenario produced 1.5-1.7 newly infected individuals per infector entry, whereas a combination of cooperative preventive measures by organizers and the spectators achieved a 99% risk reduction, corresponding to 0.009-0.012 newly infected individuals per infector entry. The expected number of newly infected individuals was calculated as 0.005 for the combination of cooperative preventive scenarios with the crude probability of a spectator being an infector of 1 × 10-5. Based on our estimates, a combination of cooperative preventions between organizers and spectators is required to prevent a viral spread at the Tokyo Olympic/Paralympic Games. Further, under the assumption that society accepts < 10 newly infected persons traced to events held during the entire Olympic/Paralympic Games, we propose a crude probability of infectors of < 5 × 10-5 as a benchmark for the suppression of the infection. This is the first study to develop a model that can assess the infection risk among spectators due to exposure pathways at a mass gathering event.
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Srivastava S, Zhao X, Manay A, Chen Q. Effective ventilation and air disinfection system for reducing coronavirus disease 2019 (COVID-19) infection risk in office buildings. SUSTAINABLE CITIES AND SOCIETY 2021; 75:103408. [PMID: 34603942 PMCID: PMC8479514 DOI: 10.1016/j.scs.2021.103408] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 09/24/2021] [Accepted: 09/25/2021] [Indexed: 05/09/2023]
Abstract
During the COVID-19 pandemic, an increasing amount of evidence has suggested that the virus can be transmitted through the air inside buildings. The ventilation system used to create the indoor environment would facilitate the transmission of the airborne infectious diseases. However, the existing ventilation systems in most buildings cannot supply sufficient clean outdoor air for diluting the virus concentration. To reduce the airborne infection risk and minimize energy consumption, especially in existing buildings with well-mixed ventilation systems, this investigation used an ultraviolet-C (UV-C) air disinfection device (Rheem's third generation products, RM3) with 99.9% disinfection efficiency to clean air carrying the COVID-19 virus (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2) which could help promote environmental sustainability and create healthy cities. This investigation assessed the impact of the RM3 UV-C units on the infection risk, the number of RM3 UV-C units required, and the strategy for decreasing the infection risk, with the use of computational-fluid-dynamics (CFD) numerical simulations. An actual office building with a combination of individual offices and workstations was selected as an example for the research. According to the numerical results, the best strategy would be to use a combination of 100% outside air and UV-C in heating, ventilation and air-conditioning (HVAC) ducts with air disinfected by the RM3 UV-C units. The infection risk in the office building could thus be reduced to a negligible level. These findings could provide theoretical basis and engineering application basis for COVID-19 epidemic prevention and control.
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Griffiths D, Sheehan L, van Vreden C, Whiteford P, Collie A. Returning to the Workplace During the COVID-19 Pandemic: The Concerns of Australian Workers. JOURNAL OF OCCUPATIONAL REHABILITATION 2021; 31:711-720. [PMID: 34131836 PMCID: PMC8204924 DOI: 10.1007/s10926-021-09990-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/04/2021] [Indexed: 06/12/2023]
Abstract
Purpose To determine the nature and prevalence of workers' concerns regarding workplaces reopening during the pandemic. To identify characteristics of workers and industries where particular concerns are more common. Method Prospective cohort study of 1063 employed Australian adults, enrolled at the start of the pandemic. Data on attitudes to workplaces reopening were collected 1 July-30 September 2020. The frequency of concerns describes infection risk and changes to work and impact on home life. Regression models examined associations between demographic and industry factors with reopening concerns. Results More than four in five (82.4%) of workers reported concerns about workplace infection risk. Just over half (53.4%) reported concerns about impacts to work and home life. Concerns were more prevalent for workers reporting psychological distress, financial stress, and among those exclusively working from home. Concerns regarding infection risk were common for workers in health care (IRR 1.16, 95% CI [1.01, 1.33]), retail (IRR 1.31, 95% CI [1.06, 1.61]), and accommodation/food service industries (IRR 1.25, 95% CI [1.01, 1.55]). Concerns regarding changes to work and home life were more common for female workers (IRR 1.24, 95% CI [1.07, 1.43]), and partners/spouses with dependent children (IRR 1.44, 95% CI [1.16, 1.79]). Conclusion Concerns of COVID-19 infection in the workplace are common. Many workers are also concerned about changes to their work and home life. The prevalence of concerns is related to the nature of work and responsibilities at home. Actions that reduce risk of workplace transmission, coupled with effective communication of infection controls, may alleviate worker concerns whilst recognising workers' family and social circumstances.
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Bu Y, Ooka R, Kikumoto H, Oh W. Recent research on expiratory particles in respiratory viral infection and control strategies: A review. SUSTAINABLE CITIES AND SOCIETY 2021; 73:103106. [PMID: 34306994 PMCID: PMC8272400 DOI: 10.1016/j.scs.2021.103106] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 06/07/2021] [Accepted: 06/15/2021] [Indexed: 05/15/2023]
Abstract
The global spread of coronavirus disease 2019 poses a significant threat to human health. In this study, recent research on the characteristics of expiratory particles and flow is reviewed, with a special focus on different respiratory activities, to provide guidance for reducing the viral infection risk in the built environment. Furthermore, environmental influence on particle evaporation, dispersion, and virus viability after exhalation and the current methods for infection risk assessment are reviewed. Finally, we summarize promising control strategies against infectious expiratory particles. The results show that airborne transmission is a significant viral transmission route, both in short and long ranges, from infected individuals. Relative humidity affects the evaporation and trajectories of middle-sized droplets most, and temperature accelerates the inactivation of SARS-CoV-2 both on surfaces and in aerosols. Future research is needed to improve infection risk models to better predict the infection potential of different transmission routes. Moreover, further quantitative studies on the expiratory flow features after wearing a mask are needed. Systematic investigations and the design of advanced air distribution methods, portable air cleaners, and ultraviolet germicidal irradiation systems, which have shown high efficacy in removing contaminants, are required to better control indoor viral infection.
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Yousefghahari B, Navari S, Sadeghi M, Soleimaniamiri S, Soleimaniamiri M, Heidari B, Babaei M, Ghodrati K, Guran A, Gholinia H. Risk of COVID-19 infection in patients with rheumatic disease taking disease-modifying anti-rheumatic drugs. Clin Rheumatol 2021; 40:4309-4315. [PMID: 34052904 PMCID: PMC8164488 DOI: 10.1007/s10067-021-05779-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 05/15/2021] [Accepted: 05/19/2021] [Indexed: 12/23/2022]
Abstract
BACKGROUND AND OBJECTIVE Patients with rheumatic disease taking long-term disease-modifying anti-rheumatic drugs (DMARDs) are expected to have a higher risk of infection due to the alterations in cellular immunity associated with these medications. However, the potential risks associated with these drugs remain unclear. This study aimed to estimate the risk of COVID-19 infection in patients with rheumatic disease taking disease-modifying anti-rheumatic drugs. METHODS Patients with autoimmune rheumatic disease taking DMARDs with or without long-term (> 6 months) HCQ treatment prior to the COVID-19 outbreak were selected consecutively. The diagnosis of COVID-19 was made based on the history of symptoms suggestive of the disease and/or serum IgG positivity. During statistical analysis, the risk of COVID-19 infection was calculated in rheumatic patients taking DMARDs versus controls, as well as in patients taking HCQ versus those who are not. The ORs and 95% CIs were also calculated. The participants in the control group were selected from individuals without RD. RESULTS A total of 800 patients with RD and 449 controls were analyzed. COVID-19 infection was detected in 16.8% of rheumatic patients versus 17.6% of controls (OR 0.95; 95% CI 0.7-1.28). The proportions of COVID-19 infection in HCQ users versus non-users were 15.3% and 18.1%, respectively (OR 0.87; 95% CI 0.61-1.26). These results remained unchanged after adjusting for all covariates using logistic regression analysis. CONCLUSION These findings indicate that rheumatic patients taking DMARDs are not at a higher risk of COVID-19 infection, and that HCQ therapy has no influence on the risk of COVID-19 infection. Key points • The risk of COVID-19 infection is not higher in patients with RD on DMARD therapy. • The prevalence of COVID-19 infection in HCQ users has not significant difference relative to non-users. • Significant percent of RD patients taking DMARDs had asymptomatic infection. • There was a positive association between leflunamide therapy and the risk of COVID-19 infection.
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Procter SR, Abbas K, Flasche S, Griffiths U, Hagedorn B, O'Reilly KM, Jit M. SARS-CoV-2 infection risk during delivery of childhood vaccination campaigns: a modelling study. BMC Med 2021; 19:198. [PMID: 34384441 PMCID: PMC8359640 DOI: 10.1186/s12916-021-02072-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 07/26/2021] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND The COVID-19 pandemic has disrupted the delivery of immunisation services globally. Many countries have postponed vaccination campaigns out of concern about infection risks to the staff delivering vaccination, the children being vaccinated, and their families. The World Health Organization recommends considering both the benefit of preventive campaigns and the risk of SARS-CoV-2 transmission when making decisions about campaigns during COVID-19 outbreaks, but there has been little quantification of the risks. METHODS We modelled excess SARS-CoV-2 infection risk to vaccinators, vaccinees, and their caregivers resulting from vaccination campaigns delivered during a COVID-19 epidemic. Our model used population age structure and contact patterns from three exemplar countries (Burkina Faso, Ethiopia, and Brazil). It combined an existing compartmental transmission model of an underlying COVID-19 epidemic with a Reed-Frost model of SARS-CoV-2 infection risk to vaccinators and vaccinees. We explored how excess risk depends on key parameters governing SARS-CoV-2 transmissibility, and aspects of campaign delivery such as campaign duration, number of vaccinations, and effectiveness of personal protective equipment (PPE) and symptomatic screening. RESULTS Infection risks differ considerably depending on the circumstances in which vaccination campaigns are conducted. A campaign conducted at the peak of a SARS-CoV-2 epidemic with high prevalence and without special infection mitigation measures could increase absolute infection risk by 32 to 45% for vaccinators and 0.3 to 0.5% for vaccinees and caregivers. However, these risks could be reduced to 3.6 to 5.3% and 0.1 to 0.2% respectively by use of PPE that reduces transmission by 90% (as might be achieved with N95 respirators or high-quality surgical masks) and symptomatic screening. CONCLUSIONS SARS-CoV-2 infection risks to vaccinators, vaccinees, and caregivers during vaccination campaigns can be greatly reduced by adequate PPE, symptomatic screening, and appropriate campaign timing. Our results support the use of adequate risk mitigation measures for vaccination campaigns held during SARS-CoV-2 epidemics, rather than cancelling them entirely.
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Liu F, Luo Z, Li Y, Zheng X, Zhang C, Qian H. Revisiting physical distancing threshold in indoor environment using infection-risk-based modeling. ENVIRONMENT INTERNATIONAL 2021; 153:106542. [PMID: 33819720 PMCID: PMC8016632 DOI: 10.1016/j.envint.2021.106542] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 03/20/2021] [Accepted: 03/22/2021] [Indexed: 05/09/2023]
Abstract
Physical distancing has been an important policy to mitigate the spread of the novel coronavirus disease 2019 (COVID-19) in public settings. However, the current 1-2 m physical distancing rule is based on the physics of droplet transport and could not directly translate into infection risk. We therefore revisit the 2-m physical distancing rule by developing an infection-risk-based model for human speaking. The key modeling framework components include viral load, droplets dispersion and evaporation, deposition efficiency, viral dose-response rate and infection risk. The results suggest that the one-size-fits-all 2-m physical distancing rule derived from the pure droplet-physics-based model is not applicable under some realistic indoor settings, and may rather increase transmission probability of diseases. Especially, in thermally stratified environments, the infection risk could exhibit multiple peaks for a long distance beyond 2 m. With Sobol's sensitivity analysis, most variance of the risk is found to be significantly attributable to the variability in temperature gradient, exposure time and breathing height difference. Our study suggests there is no such magic 2 m physical distancing rule for all environments, but it needs to be used alongside other strategies, such as using face cover, reducing exposure time, and controlling the thermal stratification of indoor environment.
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Ye Y, Qiu H. Using urban landscape pattern to understand and evaluate infectious disease risk. URBAN FORESTRY & URBAN GREENING 2021; 62:127126. [PMID: 33824634 PMCID: PMC8017915 DOI: 10.1016/j.ufug.2021.127126] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 02/26/2021] [Accepted: 03/30/2021] [Indexed: 05/24/2023]
Abstract
COVID-19 case numbers in 161 sub-districts of Wuhan were investigated based on landscape epidemiology, and their landscape metrics were calculated based on land use/land cover (LULC). Initially, a mediation model verified a partially mediated population role in the relationship between landscape pattern and infection number. Adjusted incidence rate (AIR) and community safety index (CSI), two indicators for infection risk in sub-districts, were 25.82∼63.56 ‱ and 3.00∼15.87 respectively, and central urban sub-districts were at higher infection risk. Geographically weighted regression (GWR) performed better than OLS regression with AICc differences of 7.951∼181.261. The adjusted R2 in GWR models of class-level index and infection risk were 0.697 to 0.817, while for the landscape-level index they were 0.668 to 0.835. Secondly, 16 key landscape metrics were identified based on GWR, and then a prediction model for infection risk in sub-districts and communities was developed. Using principal component analysis (PCA), development intensity, landscape level, and urban blue-green space were considered to be principal components affecting disease infection risk, explaining 73.1 % of the total variance. Cropland (PLAND and LSI), urban land (NP, LPI, and LSI) and unused land (NP) represent development intensity, greatly affecting infection risk in urban areas. Landscape level CONTAG, DIVISION, SHDI, and SHEI represent mobility and connectivity, having a profound impact on infection risk in both urban and suburban areas. Water (PLAND, NP, LPI, and LSI) and woodland (NP, and LSI) represent urban blue-green spaces, and were particularly important for infection risk in suburban areas. Based on urban landscape pattern, we proposed a framework to understand and evaluate infection risk. These findings provide a basis for risk evaluation and policy-making of urban infectious disease, which is significant for community management and urban planning for infectious disease worldwide.
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Roth M, Holtmann C, Tillmann A, Bertram B, Geerling G. [Assessment of subjective risk of infection and willingness to vaccinate against SARS-CoV-2 among German ophthalmologists : Results of a survey by DOG and BVA]. Ophthalmologe 2021; 118:675-683. [PMID: 34019126 PMCID: PMC8139227 DOI: 10.1007/s00347-021-01425-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 05/04/2021] [Accepted: 05/07/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND AND OBJECTIVE After approval of the first COVID-19 vaccines in Germany, vaccination prioritization and vaccination preparedness are central topics in the discussion on strategies to end the pandemic. How ophthalmologists evaluate their risk of infection and whether they are willing to be vaccinated has not been investigated so far. The aim of this project was to assess the subjective rating of the risk of infection and the willingness to be vaccinated among German ophthalmologists. METHODS Data were collected by an anonymous online survey conducted by the Professional Association of Ophthalmologists in Germany (BVA) and the German Ophthalmological Society (DOG) under the auspices of the University Eye Hospital Düsseldorf. The questionnaire was open for participation from 22 January to 12 February 2021. The survey was addressed to all colleagues in ophthalmology. RESULTS A total of 1162 completed questionnaires were analyzed. On average, survey respondents rated their risk of infection as 7.5 ± 1.9 (scale of 1-10; 1 = very low risk, 10 = very high risk). Of the respondents 971 (83.6%) rated their risk of infection as higher compared to other disciplines and 92.9% (n = 1079) indicated they would be willing to be vaccinated. CONCLUSION The ophthalmologists interviewed consider their professional group to be exposed to an above-average risk of SARS-COV‑2 infection compared to other disciplines. They frequently criticized the prioritization ranking of the German Ministry of Health (BMG), which deviated from the suggestions of the Standing Vaccination Committee of Germany (STIKO). The willingness to be vaccinated was very high among the surveyed German ophthalmologists.
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Shen J. Measuring the impact of mitigation measures on infection risk of covid-19 in Hong Kong since February 2020. CITIES (LONDON, ENGLAND) 2021; 114:103192. [PMID: 33776182 PMCID: PMC7985930 DOI: 10.1016/j.cities.2021.103192] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 02/22/2021] [Accepted: 03/18/2021] [Indexed: 05/05/2023]
Abstract
Is it possible to control the covid-19 pandemic in large cities like Hong Kong? Many cities have adopted various mitigation measures to contain the covid-19 pandemic. But few studies have been made to measure the impact of mitigation measures on infection risk at city level such as Hong Kong. This paper introduced three indicators to measure the infection risk of covid-19 under mitigation measures: the infection rate, the primary risk of infection and daily risk of infection. Two factors are introduced to consider the impact of mitigation measures on infection risk in Hong Kong. They are the number of trips per day and the percentage of people wearing face masks. With these two mitigation measures, the daily risk of infection was reduced from 1826.11 per million to 644.58 per million in the peak of covid-19 infection on 2 August 2020. The covid-19 infection risk would be 2.83 times higher if above mitigation measures were not adopted. The covid-19 pandemic continues in 2021 and city governments are strongly recommended to take effective measures to encourage the public to reduce unnecessary trips and wear face mask before the pandemic is fully controlled.
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Wang J, Huang J, Feng Z, Cao SJ, Haghighat F. Occupant-density-detection based energy efficient ventilation system: Prevention of infection transmission. ENERGY AND BUILDINGS 2021; 240:110883. [PMID: 33716390 PMCID: PMC7940037 DOI: 10.1016/j.enbuild.2021.110883] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/16/2021] [Accepted: 03/01/2021] [Indexed: 05/09/2023]
Abstract
Ventilation plays an important role in prevention and control of COVID-19 in enclosed indoor environment and specially in high-occupant-density indoor environments (e.g., underground space buildings, conference room, etc.). Thus, higher ventilation rates are recommended to minimize the infection transmission probability, but this may result in higher energy consumption and cost. This paper proposes a smart low-cost ventilation control strategy based on occupant-density-detection algorithm with consideration of both infection prevention and energy efficiency. The ventilation rate can be automatically adjusted between the demand-controlled mode and anti-infection mode with a self-developed low-cost hardware prototype. YOLO (You Only Look Once) algorithm was applied for occupancy detection based on video frames from surveillance cameras. Case studies show that, compared with a traditional ventilation mode (with 15% fixed fresh air ratio), the proposed ventilation control strategy can achieve 11.7% energy saving while lowering the infection probability to 2%. The developed ventilation control strategy provides a feasible and promising solution to prevent transmission of infection diseases (e.g., COVID-19) in public and private buildings, and also help to achieve a healthy yet sustainable indoor environment.
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COVID-19 and air pollution in Vienna-a time series approach. Wien Klin Wochenschr 2021; 133:951-957. [PMID: 33959810 PMCID: PMC8101341 DOI: 10.1007/s00508-021-01881-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 04/20/2021] [Indexed: 11/12/2022]
Abstract
We performed a time series analysis in Vienna, Austria, investigating the temporal association between daily air pollution (nitrogen dioxide, NO2 and particulate matter smaller than 10 µm, PM10) concentration and risk of coronavirus disease 2019 (COVID-19) infection and death. Data covering about 2 months (March–April 2020) were retrieved from public databases. Infection risk was defined as the ratio between infected and infectious. In a separate sensitivity analysis different models were applied to estimate the number of infectious people per day. The impact of air pollution was assessed through a linear regression on the natural logarithm of infection risk. Risk of COVID-19 mortality was estimated by Poisson regression. Both pollutants were positively correlated with the risk of infection with the coefficient for NO2 being 0.032 and for PM10 0.014. That association was significant for the irritant gas (p = 0.012) but not for particles (p = 0.22). Pollutants did not affect COVID-19-related mortality. The study findings might have wider implications on an interaction between air pollution and infectious agents.
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Tzamouranis DD, Chandrinos A. Dataset on the questionnaire-based survey of the perceived risk of COVID-19 infection and Contact lens (CL) wearers. Data Brief 2021; 36:107101. [PMID: 33969164 PMCID: PMC8087585 DOI: 10.1016/j.dib.2021.107101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 04/17/2021] [Accepted: 04/20/2021] [Indexed: 11/27/2022] Open
Abstract
The data set presents data collected by an online questionnaire, applying closed-ended question types (multiple-choice, Likert scale) and questions Skip Logic. Instruments from previous studies in the field of optometry such as Contact Lens User Experience (CLUE Scales), Quality of Life Questionnaire (CLIQ), Quality of Vision (QoV) Questionnaire, did not meet the needs of this study. Therefore, in order to provide a statistically valid and consistent instrument to examine the psychopathological reactions in Contact lens wearers due to COVID-19, a new questionnaire was designed. The steps followed to collect and manage data were, definition of the objectives of the study, questionnaire design, questionnaire pilot testing (validity, reliability, repeatability), data administration and results interpretation. This descriptive survey employed online data collection using an anonymized questionnaire. The questionnaire was made available via an online link on social networks from 28/09/2020 to 11/10/2020. The questionnaire, in order to record the psychopathological reactions in Contact lens wearers due to COVID-19, was structured according to three psychopathological reactions (COVID-RS scales), (a) disorganized behaviors, (b) avoidant behaviors, (c) maladaptive information consumption. Therefore includes, (a) socio-demographic variables such as, (age, gender, educational level, Professional status, geographical area of habitation), (b) Health and Consumer behavior in Contact lens wearers, (c) Perceived risk of infection due to COVID-19 in Contact lens users, with a total of 22 items and maximum completion time 4 min. The survey included 1676 participants, 1037 were Contact Lens users and completed the online questionnaire. Of them, 76.7% (795) were female and 23.3% (242) were male. The educational level of the participants was, 7.5% (8) primary education, 18.9% (197) Secondary education, 57.9% (601) Undergraduate education, 22.3% (231) Postgraduate education. According to the age groups, 68.2% (707) participants were between 18 and 34 years old, 23.4% (278) participants were between 35 and 54 years old, 4.8% (50) participants were between 55 and 74 years old, 0.2% (2) participants were 75 and over. All data were exported to Excel spreadsheets. Only the completed questionnaires were used in the analyses. Data were analyzed using the Statistical Package for Social Sciences (SPSS) software version 24. Cronbach's alpha showed for the group, Health and Consumer behavior in Contact lens wearers (6 items), to reach acceptable reliability α= 0,881. Cronbach's alpha showed for the group, Perceived risk of infection due to COVID-19 in contact lens wearers (6 items), to reach acceptable reliability α= 0,886. The data set can be used to understand the relationship between the perceived risk of Covid-19 infection and contact lens (CL) use, the potential effect of the pandemic in Health and consumer behavior in Contact lens users, to draft a survey strategy and design, to verify results, etc.
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Grindle KR. Impact of technology on community nursing during the pandemic. Br J Community Nurs 2021; 26:110-115. [PMID: 33719559 DOI: 10.12968/bjcn.2021.26.3.110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The purpose of this article is critical analysis, reflection and discussion in regards to the uses and impacts technology has had in community settings, specifically care homes during the COVID-19 pandemic. This will be investigated and supported with special emphasis on virtual assessment platforms and their use within the care homes settings, furthermore reviewing specific data collected in relation to the usage within community care homes. The article will outline the positive attributes and critically reflect upon the benefits of using audio and video conferencing when assessing patients and the beneficial impacts this has had on patients and the wider health community. While conversely addressing the obstacles and threats faced by clinicians in the use of assessment software.
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Abstract
Infektionen spielen für die Morbidität und Mortalität von Patienten mit rheumatologischen Erkrankungen eine wichtige Rolle. Das Infektionsrisiko wird zum einen durch allgemeine Faktoren wie das Alter des Patienten und vorhandene Komorbiditäten, zum anderen krankheitsbezogen durch die Aktivität der Grunderkrankung selbst und durch die laufende – insbesondere immunsuppressive – Therapie bestimmt. Dementsprechend zählen zu wichtigsten risikoverringernden Maßnahmen eine optimale Kontrolle über die Krankheitsaktivität und die Erfassung und optimale Behandlung eventuell vorhandener Komorbiditäten. Notwendig ist außerdem die Erkennung und besondere Überwachung von Patienten mit erhöhtem Infektionsrisiko, wie z. B. schweren Infektionen in der Anamnese. Weiterhin kann die Wahl der antirheumatischen Therapie das Risiko beeinflussen: risikosteigernd wirken besonders Glucocorticoide (GC), eher risikosenkend bei guter Krankheitskontrolle und optimiertem Einsatz DMARDs („disease-modifying anti-rheumatic drugs“). Schließlich sorgen prophylaktische Maßnahmen wie Schutztherapien und optimierter Impfstatus für eine Verringerung des Infektionsrisikos.
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Bhattacharya J, Chakraborty S, Yu X. A rational-choice model of Covid-19 transmission with endogenous quarantining and two-sided prevention. JOURNAL OF MATHEMATICAL ECONOMICS 2021; 93:102492. [PMID: 33568880 PMCID: PMC7862051 DOI: 10.1016/j.jmateco.2021.102492] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 12/19/2020] [Accepted: 12/22/2020] [Indexed: 05/06/2023]
Abstract
This paper offers a parsimonious, rational-choice model to study the effect of pre-existing inequalities on the transmission of COVID-19. Agents decide whether to "go out" (or self-quarantine) and, if so, whether to wear protection such as masks. Three elements distinguish the model from existing work. First, non-symptomatic agents do not know if they are infected. Second, some of these agents unknowingly transmit infections. Third, we permit two-sided prevention via the use of non-pharmaceutical interventions: the probability of a person catching the virus from another depends on protection choices made by each. We find that a mean-preserving increase in pre-existing income inequality unambiguously increases the equilibrium proportion of unprotected, socializing agents and may increase or decrease the proportion who self-quarantine. Strikingly, while higher pre-COVID inequality may or may not raise the overall risk of infection, it increases the risk of disease in social interactions.
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Tirkolaee EB, Abbasian P, Weber GW. Sustainable fuzzy multi-trip location-routing problem for medical waste management during the COVID-19 outbreak. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 756:143607. [PMID: 33220997 PMCID: PMC7654290 DOI: 10.1016/j.scitotenv.2020.143607] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 10/29/2020] [Accepted: 10/31/2020] [Indexed: 05/03/2023]
Abstract
The performance of waste management system has been recently interrupted and encountered a very serious situation due to the epidemic outbreak of the novel Coronavirus (COVID-19). To this end, the handling of infectious medical waste has been particularly more vital than ever. Therefore, in this study, a novel mixed-integer linear programming (MILP) model is developed to formulate the sustainable multi-trip location-routing problem with time windows (MTLRP-TW) for medical waste management in the COVID-19 pandemic. The objectives are to concurrently minimize the total traveling time, total violation from time windows/service priorities and total infection/environmental risk imposed on the population around disposal sites. Here, the time windows play a key role to define the priority of services for hospitals with a different range of risks. To deal with the uncertainty, a fuzzy chance-constrained programming approach is applied to the proposed model. A real case study is investigated in Sari city of Iran to test the performance and applicability of the proposed model. Accordingly, the optimal planning of vehicles is determined to be implemented by the municipality, which takes 19.733 h to complete the processes of collection, transportation and disposal. Finally, several sensitivity analyses are performed to examine the behavior of the objective functions against the changes of controllable parameters and evaluate optimal policies and suggest useful managerial insights under different conditions.
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Baby bottle and other disinfection devices used during travel to low electrical voltage (110V) regions: A practical experiment with implications for baby, lactating mothers and patient safety. Travel Med Infect Dis 2021; 40:101991. [PMID: 33610764 DOI: 10.1016/j.tmaid.2021.101991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 02/10/2021] [Accepted: 02/11/2021] [Indexed: 11/20/2022]
Abstract
BACKGROUND Baby bottle steam disinfectors are important for the disinfection of devices used with baby nutrition, lactating mothers and respiratory patients (e.g. nebulisers). There have been no reports to date describing the effect of incorrect voltage on thermal performance. It was the aim of this study to evaluate thermal output, at low (110 V) voltage compared to 220 V. Such data will determine if variation in voltage, results in temperature differences, constituting a microbiological safety risk. METHODS Thermal performance was evaluated by positioning calibrated thermocouple probes in multiple locations operating the device at 110 V and 220-240 V. RESULTS Within the upper tray at 220-240 V, a maximum temperature (TempMAX) of 100 °C was achieved, with the unit remaining at 90 °C for 420 s (A0 = 3000), whereas at 110 V, TempMAX = 71.1 °C, remaining at >70 °C for 630 s. Most importantly, when the lower tray of the device was examined at 110 V, TempMAX = 48.6 °C at one location, remaining >40 °C for 1140 s, whereas at 220-240 V, the lowest temperature achieved was 86.1 °C, with an A0 equivalence of A0 = 60. CONCLUSIONS This study showed that input voltage of 110 V to the baby bottle steam disinfector had an adverse effect on thermal performance, by not achieving intended time/temperature combinations, compared to 220-240 V. Parents of babies and infants need to be made aware of the microbiological safety risks of operating such devices outside the manufacturers' specification. For the safety of babies, infants, mothers and patients, users must ensure that such devices are always operated safely within manufacturer's specifications and instructions for use.
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Heidemann J, Schmitz B, Kostev K. Association between antiseizure medication use and risk of urinary tract infection: A case-control study. Epilepsy Behav 2021; 115:107502. [PMID: 33323337 DOI: 10.1016/j.yebeh.2020.107502] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/31/2020] [Accepted: 09/11/2020] [Indexed: 12/23/2022]
Abstract
AIM The aim of this study was to analyze the association between antiseizure medication (ASM) and the risk of urinary tract infections (UTI) in patients with epilepsy treated in general practices in Germany. METHODS This study includes a total of 2201 patients (mean age: 61.4) whose first documented UTI diagnosis occurred between January 2015 and December 2019 (index date) and who were prescribed at least one ASM in 1198 general practices in Germany within one year prior to the index date. Based on a case-control design, the association between predefined criteria and UTI was investigated by matching (1:1) controls without UTI to cases with UTI by sex, age, and codiagnoses. Logistic regression models were used to analyze the association between ASM use and UTI risk. RESULTS In the first regression model, phenytoin (PHT), primidone, carbamazepine (CBZ), and valproate (VPA) were associated with an increased risk of UTI. In the second model, these associations were confirmed with effects per prescription for PHT, primidone, CBZ, and VPA use. Additionally, the effect per prescription was significant for oxcarbazepine (OXC), topiramate, and gabapentin. CONCLUSION The study found that PHT, primidone, CBZ, and VPA in particular are associated with an increased risk of infections of the urinary tract. Oxcarbazepine, topiramate, and gabapentin are also associated with increased risk of UTI, albeit to a less significant extent. In general, the immunological and hematological side effects of these molecules may play an important role in the development of UTI under anticonvulsant therapy.
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Jones DL, Baluja MQ, Graham DW, Corbishley A, McDonald JE, Malham SK, Hillary LS, Connor TR, Gaze WH, Moura IB, Wilcox MH, Farkas K. Shedding of SARS-CoV-2 in feces and urine and its potential role in person-to-person transmission and the environment-based spread of COVID-19. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 749:141364. [PMID: 32836117 PMCID: PMC7836549 DOI: 10.1016/j.scitotenv.2020.141364] [Citation(s) in RCA: 238] [Impact Index Per Article: 59.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 07/27/2020] [Accepted: 07/28/2020] [Indexed: 04/14/2023]
Abstract
The recent detection of SARS-CoV-2 RNA in feces has led to speculation that it can be transmitted via the fecal-oral/ocular route. This review aims to critically evaluate the incidence of gastrointestinal (GI) symptoms, the quantity and infectivity of SARS-CoV-2 in feces and urine, and whether these pose an infection risk in sanitary settings, sewage networks, wastewater treatment plants, and the wider environment (e.g. rivers, lakes and marine waters). A review of 48 independent studies revealed that severe GI dysfunction is only evident in a small number of COVID-19 cases, with 11 ± 2% exhibiting diarrhea and 12 ± 3% exhibiting vomiting and nausea. In addition to these cases, SARS-CoV-2 RNA can be detected in feces from some asymptomatic, mildly- and pre-symptomatic individuals. Fecal shedding of the virus peaks in the symptomatic period and can persist for several weeks, but with declining abundances in the post-symptomatic phase. SARS-CoV-2 RNA is occasionally detected in urine, but reports in fecal samples are more frequent. The abundance of the virus genetic material in both urine (ca. 102-105 gc/ml) and feces (ca. 102-107 gc/ml) is much lower than in nasopharyngeal fluids (ca. 105-1011 gc/ml). There is strong evidence of multiplication of SARS-CoV-2 in the gut and infectious virus has occasionally been recovered from both urine and stool samples. The level and infectious capability of SARS-CoV-2 in vomit remain unknown. In comparison to enteric viruses transmitted via the fecal-oral route (e.g. norovirus, adenovirus), the likelihood of SARS-CoV-2 being transmitted via feces or urine appears much lower due to the lower relative amounts of virus present in feces/urine. The biggest risk of transmission will occur in clinical and care home settings where secondary handling of people and urine/fecal matter occurs. In addition, while SARS-CoV-2 RNA genetic material can be detected by in wastewater, this signal is greatly reduced by conventional treatment. Our analysis also suggests the likelihood of infection due to contact with sewage-contaminated water (e.g. swimming, surfing, angling) or food (e.g. salads, shellfish) is extremely low or negligible based on very low predicted abundances and limited environmental survival of SARS-CoV-2. These conclusions are corroborated by the fact that tens of million cases of COVID-19 have occurred globally, but exposure to feces or wastewater has never been implicated as a transmission vector.
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