Microbial Risk Analysis最新文献

{"title":"Assessment of COVID-19 risk and prevention effectiveness among spectators of mass gathering events","authors":"Tetsuo Yasutaka ,&nbsp;Michio Murakami ,&nbsp;Yuichi Iwasaki ,&nbsp;Wataru Naito ,&nbsp;Masaki Onishi ,&nbsp;Tsukasa Fujita ,&nbsp;Seiya Imoto","doi":"10.1016/j.mran.2022.100215","DOIUrl":"10.1016/j.mran.2022.100215","url":null,"abstract":"<div><p>There is a need to evaluate and minimize the risk of novel coronavirus infections at mass gathering events, such as sports. In particular, to consider how to hold mass gathering events, it is important to clarify how the local infection prevalence, the number of spectators, the capacity proportion, and the implementation of preventions affect the infection risk. In this study, we used an environmental exposure model to analyze the relationship between infection risk and infection prevalence, the number of spectators, and the capacity proportion at mass gathering events in football and baseball games. In addition to assessing risk reduction through the implementation of various preventive measures, we assessed how face-mask-wearing proportion affects infection risk. Furthermore, the model was applied to estimate the number of infectors who entered the stadium and the number of newly infected individuals, and to compare them with actual reported cases. The model analysis revealed an 86–95% reduction in the infection risk due to the implementation of face-mask wearing and hand washing. Under conditions in which vaccine effectiveness was 20% and 80%, the risk reduction rates of infection among vaccinated spectators were 36% and 96%, respectively. Among the individual measures, face-mask wearing was particularly effective, and the infection risk increased as the face-mask-wearing proportion decreased. A linear relationship was observed between infection risk at mass gathering events and the infection prevalence. Furthermore, the number of newly infected individuals was also dependent on the number of spectators and the capacity proportion independent of the infection prevalence, confirming the importance of considering spectator capacity in infection risk management. These results highlight that it is beneficial for organisers to ensure prevention compliance and to mitigate or limit the number of spectators according to the prevalence of local infection. Both the estimated and reported numbers of newly infected individuals after the events were small, below 10 per 3–4 million spectators, despite a small gap between these numbers.</p></div>","PeriodicalId":48593,"journal":{"name":"Microbial Risk Analysis","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2352352222000159/pdfft?md5=862424f5eb5ef881b107c43819c82c35&pid=1-s2.0-S2352352222000159-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42380480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A climate-driven model for predicting the level of Vibrio parahaemolyticus in oysters harvested from Taiwanese farms using elastic net regularized regression","authors":"Nodali Ndraha ,&nbsp;Hsin-I Hsiao","doi":"10.1016/j.mran.2022.100201","DOIUrl":"10.1016/j.mran.2022.100201","url":null,"abstract":"<div><p>This study aimed at, and developed, a climate-driven model for predicting the abundance of <em>V. parahaemolyticus</em> in oysters based on the local climatological and environmental conditions in Taiwan. The predictive model was constructed using the elastic net machine learning method, and the most influential predictors were evaluated using a permutation-based approach. The abundance of <em>V. parahaemolyticus</em><span> in oysters in different seasons, time horizons, and representative concentration pathways (RCPs) were predicted using the Elastic-net machine learning model. The results showed: (1) the variation in wind speed or gust wind speed, sea surface temperature, precipitation, and pH influenced the prediction of </span><em>V. parahaemolyticus</em> concentration in oysters, and (2) the level of <em>V. parahaemolyticus</em> in oysters in Taiwan was projected to be increased by 40–67% in the near future (2046–2065) and by 39–86% by the end of twentieth-century (2081–2100) if the global temperature continues to increase due to climate change. The findings in this study may be used as inputs for quantifying the <em>V. parahaemolyticus</em> infection risk from eating this seafood in Taiwan.</p></div>","PeriodicalId":48593,"journal":{"name":"Microbial Risk Analysis","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42564558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cryptosporidium’s burden of disease attributable to consumption of wastewater-irrigated raw vegetables","authors":"Marzieh Farhadkhani ,&nbsp;Mahnaz Nikaeen ,&nbsp;Mahdi Hadi ,&nbsp;Hossein Nikaein ,&nbsp;Absar Alum ,&nbsp;Morteza Abbaszadegan","doi":"10.1016/j.mran.2022.100218","DOIUrl":"https://doi.org/10.1016/j.mran.2022.100218","url":null,"abstract":"<div><p><span>Conventional wastewater treatment plants do not effectively remove parasitic protozoa resulting in their presence in wastewater effluent. Therefore, agricultural reuse of wastewater effluent could be a route of </span><span><em>Cryptosporidium</em></span> transmission into the food chain. Samples of secondary wastewater, wastewater-irrigated soil and vegetable samples were collected from an experimental field and analyzed using real-time PCR for quantification of <em>Cryptosporidium</em> oocysts. Quantitative microbial risk analysis (QMRA) was performed to determine the annual disease burden from <em>Cryptosporidium</em> associated with consumption of wastewater-irrigated vegetables. Detection of <span><em>Clostridium perfringens</em></span><span> spores as a potential indicator for the presence of </span><em>Cryptosporidium</em> was also performed. <em>Cryptosporidium</em> was observed in 64% of the effluent samples ranging from 16 to 162 oocysts L⁻¹, whereas no oocysts were detected in wastewater-irrigated soil and the vegetable samples. The mean annual disease burden for consumption of lettuce (6.6 × 10⁻⁵ DALY per person per year (pppy)) was higher than spring onion (3.4 × 10⁻⁶ DALY pppy) which both exceeding the WHO guideline of 10⁻⁶ DALYs pppy. However, the disease burden was within the acceptable range considering the less stringent level of 10⁻⁴ DALY pppy. <em>Clostridium</em> spores were detected in 92% of the effluent samples with no relationship with the presence of <em>Cryptosporidium</em>. The results of this study suggest that agricultural reuse of treated wastewater may not be a major health concern of cryptosporidiosis in a semi-arid region. However, because of the higher risk from lettuce, the choice of an appropriate crop would be needed to completely meet the WHO recommendations for safe reuse of wastewater. The accuracy of the QMRA model could be improved by further investigating the decay rate of oocysts in the same region.</p></div>","PeriodicalId":48593,"journal":{"name":"Microbial Risk Analysis","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136434731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Parameter estimates to support future risk assessment of Mycobacterium bovis in raw milk cheese","authors":"Áine B. Collins ,&nbsp;Simon J. More","doi":"10.1016/j.mran.2022.100204","DOIUrl":"10.1016/j.mran.2022.100204","url":null,"abstract":"<div><p>Zoonotic tuberculosis, caused by <em>Mycobacterium bovis</em>, is mainly linked to the consumption of raw milk from infected cows. In many countries, cases are rare, due to pasteurisation of milk and national programmes to control <em>M. bovis</em> infection in cattle. Speciality cheeses, which are often produced using raw milk, present challenges to risk managers in countries where <em>M. bovis</em> is endemic or (re-) emerging. A key concern is the potential risk of zoonotic transmission of <em>M. bovis</em> via the consumption of dairy products produced using raw milk originating from herds infected with <em>M. bovis</em> (bovine tuberculosis, bTB). The aim of this study was to determine parameter estimates to support the future risk assessment of <em>M. bovis</em> in raw milk cheese. In this study, the hazard was identified as viable <em>M. bovis</em> organisms in raw milk cheese. Parameters of interest in this study related to exposure assessment (the estimated extent of human exposure to viable <em>M. bovis</em> organisms) and hazard characterisation (the risk posed to human health following exposure to viable <em>M. bovis</em> organisms). The pathway for exposure assessment was visualised using a conceptual framework, which describes the steps through which <em>M. bovis</em> may be transferred from an infected animal(s) through manufacturing to the final cheese product. Estimation of most parameters for exposure assessment and hazard characterisation was undertaken using systematic literature reviews. Estimates could be derived for many parameters, but not all. In particular, the number of <em>M. bovis</em> organisms excreted in the milk and present in the faeces of infected cattle are unknown. There is zero-tolerance for <em>M. bovis</em> in foods of animal origin destined for human consumption in European legislation. This work has highlighted important gaps in knowledge, and areas for further research. For each of the parameters for which estimates are available, we outline the types/sources of uncertainty as reflected in relevant published papers. In any future application of these parameter estimates, care will be needed to reflect the uncertainties associated with these elements of exposure assessment.</p></div>","PeriodicalId":48593,"journal":{"name":"Microbial Risk Analysis","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2352352222000044/pdfft?md5=6b93654bac1c72d9cfc9b7895dee35c4&pid=1-s2.0-S2352352222000044-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45453917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Risk and socio-economic impact for Staphylococcus aureus foodborne illness by ready-to-eat salad consumption","authors":"Yewon Lee ,&nbsp;Hyemin Oh ,&nbsp;Yeongeun Seo ,&nbsp;Joohyun Kang ,&nbsp;Eunyoung Park ,&nbsp;Yohan Yoon","doi":"10.1016/j.mran.2022.100219","DOIUrl":"10.1016/j.mran.2022.100219","url":null,"abstract":"<div><p>Microbial risk assessment is a valuable tool to provide scientific evidence to control food safety. Therefore, this study evaluated the risk of foodborne illness caused by <em>Staphylococcus aureus</em> in ready-to-eat (RTE) salad products and economic impact. The prevalence of <em>S. aureus</em> in salads, the RTE salad consumption, and distribution conditions (time and temperature) in market parameters were determined, and the data were analysed using the @RISK program to determine the appropriate probabilistic distribution. Predictive models were developed to describe the fate of <em>S. aureus</em> under distribution conditions. A simulation model was prepared with the collected data to calculate the risk of illness per person per day, and this risk was used to calculate the economic impact. <em>S. aureus</em> was detected in 2% of RTE salads<em>,</em> and the initial contamination level was calculated using the Beta distribution. Baranyi model was used to calculate the maximum specific growth rate (<em>μ</em>_max), lag phase duration (<em>LPD</em>), and the secondary models well described the temperature effect on <em>LPD</em> and <em>μ</em>_max with <em>R²</em> values of 0.973–0.979. Also, the root mean square error values of 0.362 suggested that the model performance was appropriate. Lognormal distribution estimated that the average daily consumption amount and ratio was 137.7 g and 9.8%, respectively. The simulation model showed that the average probability of <em>S. aureus</em> foodborne illness following RTE salad consumption was 2.1 × 10⁻⁹ per person per day. The probability was used to estimate the socio-economic burden, and the annual socio-economic cost was calculated as $48,343.</p></div>","PeriodicalId":48593,"journal":{"name":"Microbial Risk Analysis","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49336612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Disease burden from simultaneous exposure of Cryptosporidium sp. and Giardia sp. and land use vulnerability assessment in a Costa Rican drinking water system","authors":"Eric Morales ,&nbsp;Gabriel Ibarra ,&nbsp;Liliana Reyes ,&nbsp;Kenia Barrantes ,&nbsp;Rosario Achí ,&nbsp;Luz Chacón","doi":"10.1016/j.mran.2022.100213","DOIUrl":"10.1016/j.mran.2022.100213","url":null,"abstract":"<div><p>Human and animal feces are one of the main pollutants in drinking water systems (DWS). Both sources of fecal pollution are related to environmental conditions, such as poor land use management and little micro-basin protection. <em>Cryptosporidium</em> sp. and <em>Giardia</em> sp. are zoonotic protozoan water and foodborne transmitted parasitic pathogens and a frequent cause of diarrhea in children in low- and middle-income countries. In Latin America, DWS microbial risk assessment of these parasites is scarce. The aim of this study was to apply land use analysis, quantitative microbial risk assessment (QMRA), and disease burden (DALY; disability-adjusted life years) estimation of <em>Cryptosporidium</em> sp. and <em>Giardia</em> sp. for DWS that supplies 1.4% of the Costa Rican population. Land use analysis showed pollution sources and urban activities at the catchment area of all micro-basins, demonstrating the pollution's vulnerability, especially near to catchment sites of the DWS. The risk of infection by <em>Cryptosporidium</em> sp. and <em>Giardia</em> sp. was higher than US EPA standards, and the health burdens were above WHO recommendations. The higher risk of infection was observed in the micro-basins with the higher area of urban use, mainly in the buffer zones. QMRA and land use analysis are useful tools for the characterization of possible pollution foci in hazard identification.</p></div>","PeriodicalId":48593,"journal":{"name":"Microbial Risk Analysis","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45789478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of the transfer probability of Salmonella ser. Typhimurium between pork and a cutting knife in an experimental model","authors":"Eduardo de Freitas Costa ,&nbsp;Claudia Navarrete Rivas ,&nbsp;Vanessa Bielefeld Leotti ,&nbsp;Marisa Cardoso ,&nbsp;Luis Gustavo Corbellini","doi":"10.1016/j.mran.2022.100203","DOIUrl":"10.1016/j.mran.2022.100203","url":null,"abstract":"<div><p>Cross-contamination is an important event for bacterial transfer throughout the pork production chain. In Brazil, <em>Salmonella</em> sp. is the most relevant hazard in the pork industry, and further knowledge concerning its contamination is essential for in-depth risk assessments. Thus, we aimed to assess the transfer probability of <em>Salmonella</em> sp. between a knife and pork in a domestic kitchen scenario to provide parametrization for incorporating transfer of <em>Salmonella</em> sp. in risk assessment models. To estimate <em>Salmonella</em> Typhimuium transfer rates between contaminated pork and a knife blade during cutting, 23 independent experiments were performed. A Bayesian inference was utilized to determine the transfer probability, capturing the uncertainty generated in the transfer probability experiments. The mean transfer probability was 0.03 for knife to pork [0.029; 0.032] 95% credible interval (CrI) and 0.0042 for pork to knife [0.0041; 0.0043] 95% CrI. The probabilistic estimate of the transfer probability of <em>Salmonella</em> sp. during pork cutting gives insights on a relevant parameter for the consumer phase of the pork production industry in Brazil, allowing for enhanced risk assessment models.</p></div>","PeriodicalId":48593,"journal":{"name":"Microbial Risk Analysis","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2352352222000032/pdfft?md5=d2ce85724b7743148da8376b4ac790e5&pid=1-s2.0-S2352352222000032-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46984941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbiological profile and modeling the survival of Escherichia coli ATCC 25922 in Amlou: A traditional Moroccan spread food","authors":"Youssef Ezzaky ,&nbsp;Mariem Zanzan ,&nbsp;Fouad Achemchem ,&nbsp;Antonio Valero ,&nbsp;Fatima Hamadi","doi":"10.1016/j.mran.2022.100216","DOIUrl":"10.1016/j.mran.2022.100216","url":null,"abstract":"<div><p>This study was carried out to assess the bacteriological profile and to model the combined effects of physicochemical parameters on <em>Escherichia coli</em> ATCC 25922 levels in <em>Amlou</em>, a typical Moroccan traditional spread food made with argan oil, sweet almonds, and honey or sugar. Microbiological analyses of the samples (<em>n</em><span><span> = 44), collected from different traditional producers, included total viable count (TVC), total </span>coliforms (TC), fecal coliforms (FC), </span><em>E. coli,</em><span> lactic acid bacteria (LAB), yeasts and molds (YM), </span><span><em>Staphylococcus aureus</em><span><em>, Salmonella, and </em><em>Listeria</em></span></span> spp<em>.</em> The results showed that 61% of samples met the Moroccan hygiene standards for vegetable paste spreads, with contamination levels of 4.21, 2.94, 2.38, 1.87, and 1.50 log cfu/g for TVC, YM, TC, FC, and <em>E. coli</em>, respectively. <em>S. aureus</em> was detected in 6.82% of <em>Amlou</em> samples, while <em>Salmonella</em> and <em>Listeria</em> spp. were not detected in any of the analyzed samples. On the other hand, the effects of water activity (a_w<span>) (0.44, 0.50, 0.53), temperature (23, 30 °C), and pH (5.5, 6.5) on the kinetics parameters, inactivation rate (IR, log cfu/g/d), and shoulder period (SP, d) of </span><em>E. coli</em> ATCC 25922, were investigated. The survival curves generated under different conditions were fitted using the Baranyi model. Secondary modeling for the combined effects of a_w, temperature, and pH on the survival parameters was carried out using a polynomial equation. Finally, the goodness of fit was assessed for the survival kinetics of <em>E. coli</em>. Root mean square error (RMSE) and standard error of prediction (%SEP) obtained were 0.20 and 10.22% for IR and 0.24 and 40.01% for SP. These models can provide an estimate of <em>E. coli</em> inactivation in <em>Amlou</em>. Further studies should consider other factors such as argan oil concentration and amount of protein before being applied to ensure food safety for <em>E. coli</em> control in <em>Amlou</em>.</p></div>","PeriodicalId":48593,"journal":{"name":"Microbial Risk Analysis","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43785954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using thermodynamic equilibrium models to predict the effect of antiviral agents on infectivity: Theoretical application to SARS-CoV-2 and other viruses.","authors":"Paul Gale","doi":"10.1016/j.mran.2021.100198","DOIUrl":"10.1016/j.mran.2021.100198","url":null,"abstract":"<div><p>Thermodynamic equilibrium models predict the infectivity of novel and emerging viruses using molecular data including the binding affinity of the virus to the host cell (as represented by the association constant K_{a_virus_T}) and the probability, p_virogenesis, of the virus replicating after entry to the cell. Here those models are adapted based on the principles of ligand binding to macromolecules to assess the effect on virus infectivity of inhibitor molecules which target specific proteins of the virus. Three types of inhibitor are considered using the thermodynamic equilibrium model for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection of the human lung with parameters for the strength and nature of the interaction between the target virus protein and the inhibitor molecule. The first is competitive inhibition of the SARS-CoV-2 spike glycoprotein (SGP) trimer binding to its human angiotensin converting enzyme 2 (ACE2) receptor by unfractionated heparin (UFH). Using a novel approach presented here, a value of K_{a_virus_T} = 3.53 × 10¹⁷ M⁻¹ is calculated for SARS-CoV-2 from the IC₅₀ for inhibition by UFH of SARS-CoV-2 plaque formation in cell culture together with the dissociation constant K_VI of 0.73 × 10⁻¹⁰ M reported for heparin binding to SARS-CoV-2 SGP trimer. Such a high K_{a_virus_T} limits the effectiveness of competitive inhibitors such as UFH. The second is the attachment of a nanoparticle such as a zinc oxide tetrapod (ZnOT) to the virus shell as for herpes simplex virus (HSV). The increase in molecular weight through ZnOT attachment is predicted to decrease K_{a_virus_T} by orders of magnitude by making the entropy change (ΔS_{a_immob}) on immobilisation of the ZnOT:virus complex on cell binding more negative than for the virus alone. According to the model, ZnOT acts synergistically with UFH at the IC₅₀ of 33 μg/cm³ which together decrease viral infectivity by 61,000-fold compared to the two-fold and three-fold decreases predicted for UFH alone at the IC₅₀ and for ZnOT alone respectively. According to the model here, UFH alone at its peak deliverable dose to the lung of 1,000 μg/cm³ only decreases infectivity by 31-fold. Practicable approaches to target and decrease ΔS_{a_immob} for respiratory viruses should therefore be considered. The combination of decreasing ΔS_{a_immob} together with blocking the interaction of virus surface protein with its host cell receptor may achieve synergistic effects for faecal-oral viruses and HSV. The third is reversible noncompetitive inhibition of the viral main protease (M^pro) for which the decrease in p_virogenesis is assumed to be proportional to the decrease in enzyme activity as predicted by enzyme kinetic equations for a given concentration of inhibitor which binds to M<sup>pro","PeriodicalId":48593,"journal":{"name":"Microbial Risk Analysis","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8642839/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39721646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strain Wars: Competitive interactions between SARS-CoV-2 strains are explained by Gibbs energy of antigen-receptor binding","authors":"Marko Popovic ,&nbsp;Marta Popovic","doi":"10.1016/j.mran.2022.100202","DOIUrl":"10.1016/j.mran.2022.100202","url":null,"abstract":"<div><p>Since the beginning of the COVID-19 pandemic, SARS-CoV-2 has mutated several times into new strains, with an increased infectivity. Infectivity of SARS-CoV-2 strains depends on binding affinity of the virus to its host cell receptor. In this paper, we quantified the binding affinity using Gibbs energy of binding and analyzed the competition between SARS-CoV-2 strains as an interference phenomenon. Gibbs energies of binding were calculated for several SARS-SoV-2 strains, including Hu-1 (wild type), B.1.1.7 (alpha), B.1.351 (beta), P.1 (Gamma), B.1.36 and B.1.617 (Delta). The least negative Gibbs energy of binding is that of Hu-1 strain, -37.97 kJ/mol. On the other hand, the most negative Gibbs energy of binding is that of the Delta strain, -49.50 kJ/mol. We used the more negative Gibbs energy of binding to explain the increased infectivity of newer SARS-CoV-2 strains compared to the wild type. Gibbs energies of binding was found to decrease chronologically, with appearance of new strains. The ratio of Gibbs energies of binding of mutated strains and wild type was used to define a susceptibility coefficient, which is an indicator of viral interference, where a virus can prevent or partially inhibit infection with another virus.</p></div>","PeriodicalId":48593,"journal":{"name":"Microbial Risk Analysis","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8816792/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39792280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}