scholarly journals Environmental Factors Contribute to the Transmissibility of COVID-19: Evidence from an Improved SEIR Model

Author(s):  
Jie Li ◽  
Kun Jia ◽  
Wenwu Zhao ◽  
Bo Yuan ◽  
Yanxu Liu

Abstract COVID-19 is ravaging Brazil, and its spread shows spatial heterogeneity. Changes in the environment have been implicated as potential factors involved in COVID-19 transmission. However, considerable research efforts have not elucidated the risk of environmental factors on COVID-19 transmission from the perspective of infectious disease dynamics. The aim of this study is to model the influence of the environment on COVID-19 transmission and to analyze how the socio-ecological factors affecting the probability of virus transmission in 10 states dramatically shifted during the early stages of the epidemic in Brazil. First, this study used a Pearson correlation to analyze the interconnection between COVID-19 morbidity and socio-ecological factors, and identified factors with significant correlations as the dominant factors affecting COVID-19 transmission. Then, the time-lag effect of dominant factors on the morbidity of COVID-19 was investigated by constructing a distributed lag nonlinear model, and the results were considered to be an improvement over the SEIR model. Lastly, a machine learning method was introduced to explore the nonlinear relationship between the environmental propagation probability and socio-ecological factors. By analyzing the impact of environmental factors on virus transmission, it can be found that population mobility directly caused by human activities had a greater impact on virus transmission than temperature and humidity. The heterogeneity of meteorological factors can be accounted for by the diverse climate patterns in Brazil. The improved SEIR model was adopted to explore the interconnection of COVID-19 transmission and the environment, which revealed a new strategy to probe the causal links between them.

Agriculture ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 502
Author(s):  
Junior Corneille Fingu-Mabola ◽  
Frédéric Francis

Aphids are responsible for the spread of more than half of the known phytovirus species. Virus transmission within the plant–aphid–phytovirus pathosystem depends on vector mobility which allows the aphid to reach its host plant and on vector efficiency in terms of ability to transmit phytoviruses. However, several other factors can influence the phytoviruses transmission process and have significant epidemiological consequences. In this review, we aimed to analyse the aphid behaviours and influencing factors affecting phytovirus spread. We discussed the impact of vector host-seeking and dispersal behaviours mostly involved in aphid-born phytovirus spread but also the effect of feeding behaviours and life history traits involved in plant–aphid–phytovirus relationships on vector performances. We also noted that these behaviours are influenced by factors inherent to the interactions between pathosystem components (mode of transmission of phytoviruses, vector efficiency, plant resistance, …) and several biological, biochemical, chemical or physical factors related to the environment of these pathosystem components, most of them being manipulated as means to control vector-borne diseases in the crop fields.


2020 ◽  
Vol 45 (2) ◽  
pp. 7900-7915
Author(s):  
Mostakim Lahcen ◽  
Fetnassi Nidal ◽  
Ghamizi Mohamed

Measuring the phytodiversity and determining environmental factors affecting the abundance and distribution of riparian plants of Zat sub-basin in Morocco were carried out in this study. A hypothesis was tested whether there is any statistically significant difference in environmental parameters and plants communities among the Zat River and its tributaries. For this purpose, water quality parameters such as temperature, pH, salinity, electrical conductivity, Dissolved Oxygen, nitrate and phosphorus concentration, and riparian plants diversity were estimated at 17 stations along the Zat River and its tributaries during the periods (2018 and 2019). The Canonical Correspondence Analysis (CCA) and Pearson correlation were preformed to assess the relationship between environmental parameters, and the distribution and abundance of riparian plants inventoried. The presence of 113 species was recorded, distributed between 43 families and 97 genera, 9 of which were floating-leaved, 24 submerged, and 80 emergent plants. The rare and threatened species inventoried were represented by 7 taxa, whereas 6 species are reported as endemic. Raunkiaer classification showed a dominance of therophytes (38.39%) over the other groups. According to CCA, the abiotic parameters (DO, elevation, salinity and nitrate concentration) were statistically significant parameters governing the distribution and abundance of the riparian plants inventoried. The results obtained reveal the state of the riparian vegetation in the Zat subBasin, therefore we can consider them as a reliable component for the assessment of the ecological status of the aquatic environment.


Author(s):  
Hua Wu ◽  
Wichai Eungpinichpong ◽  
Hui Ruan ◽  
Xinding Zhang ◽  
Sansan Wang ◽  
...  

Abstract Background: Preschooler inactivity and insufficient motor development have serious long-term consequences. The Chinese Ministry of Education launched a nationwide football-focused pilot project aimed at kindergartens in 2019 and issued the policy “Notice on the Establishment of National Football Kindergartens” in 2020. However, the impact of fundamental movement skills (FMS) interventions on other aspects of child development is unclear. Aim: This study will evaluate the effects of ball skills physical education projects on the development of Chinese preschoolers’ physical, motor, cognitive, and social competencies and examine the influencing factors. Method: This is a quasi-experimental study evaluating how well the “Hello Sunshine” curriculum project promotes children’s development over 10 weeks. The trial will be conducted from September 2021 to November 2021 in 12 classes from 3 kindergartens with a total of 249 children aged 4 to 6 years in Haikou, China. Pre- and posttest analyses will include tests on participants’ physical fitness, FMS, cognitive self-regulation, and emotional competence. Participants’ background information will be collected through questionnaires answered by parents and teachers. The intervention will focus on game-based basic ball skills. Findings: If this intervention provides evidence that these skills improve children’s multidimensional development, it will support the promotion of similar programs in China. We will also outline the social-ecological factors affecting the intervention’s results, providing further information for improving pedagogical methods related to preschool ball skills.


2020 ◽  
Author(s):  
Benn Sartorius ◽  
Andrew Lawson ◽  
Rachel L. Pullan

Abstract Background: COVID-19 caseloads in England appear have passed through a first peak, with evidence of an emerging second wave. To ensure continued response to the epidemic is most effective, it is imperative to better understand both retrospectively and prospectively the geographical evolution of COVID-19 caseloads and deaths, identify localised areas in space-time at significantly higher risk, quantify the impact of changes in localised population mobility (or movement) on caseloads, identify localised risk factors for increased mortality and project the likely course of the epidemic at small-area resolution in coming weeks.Methods: We applied a Bayesian space–time SEIR model to assess the spatiotemporal variability of COVID-19 caseloads (transmission) and deaths at small-area scale in England (Middle Layer Super Output Area [MSOA], 6791 units) and by week (using observed data from week 5 to 34), including key determinants, the modelled transmission dynamics and spatial-temporal random effects. We also estimate the number of cases and deaths at small-area resolution with uncertainty projected forward in time by MSOA (up to week 51 of 2020), the impact mobility reductions (and subsequent easing) have had on COVID-19 caseloads and quantify the impact of key socio-demographic risk factors on COVID-19 related mortality risk by MSOA.Results: Reductions in population mobility due the course of the first lockdown had a significant impact on the reduction of COVID-19 caseloads across England, however local authorities have had a varied rate of reduction in population movement which our model suggest has substantially impacted the geographic heterogeneity in caseloads at small-area scale. The steady gain in population mobility, observed from late April, appears to have contributed to a slowdown in caseload reductions towards late June and subsequent steady increase signalling the start of the second wave. MSOA with higher proportions of elderly (70+ years of age) and elderly living in deprivation, both with very distinct geographic distributions, have a significantly elevated COVID-19 mortality rates.Conclusions: While non-pharmaceutical interventions (that is, reductions in population mobility and social distancing) had a profound impact on the trajectory of the first wave of the COVID-19 outbreak in England, increased population mobility appears to have contributed to the current increase signalling the start of the second wave. A number of contiguous small-areas appear to be at a significant elevated risk of high COVID-19 transmission, many of which are also at increased risk for higher mortality rates. A geographically staggered re-introduction of intensified social distancing measures is advised and limited cross MSOA movement if the magnitude and geographic extent of the second wave is to be reduced.


Author(s):  
Peng Shi ◽  
Yinqiao Dong ◽  
Huanchang Yan ◽  
Xiaoyang Li ◽  
Chenkai Zhao ◽  
...  

ABSTRACTOBJECTIVETo investigate the impact of temperature and absolute humidity on the coronavirus disease 2019 (COVID-19) outbreak.DESIGNEcological study.SETTING31 provincial-level regions in mainland China.MAIN OUTCOME MEASURESData on COVID-19 incidence and climate between Jan 20 and Feb 29, 2020.RESULTSThe number of new confirm COVID-19 cases in mainland China peaked on Feb 1, 2020. COVID-19 daily incidence were lowest at -10 °C and highest at 10 °C, while the maximum incidence was observed at the absolute humidity of approximately 7 g/m3. COVID-19 incidence changed with temperature as daily incidence decreased when the temperature rose. No significant association between COVID-19 incidence and absolute humidity was observed in distributed lag nonlinear models. Additionally, A modified susceptible-exposed-infectious-recovered (M-SEIR) model confirmed that transmission rate decreased with the increase of temperature, leading to further decrease of infection rate and outbreak scale.CONCLUSIONTemperature is an environmental driver of the COVID-19 outbreak in China. Lower and higher temperatures might be positive to decrease the COVID-19 incidence. M-SEIR models help to better evaluate environmental and social impacts on COVID-19.What is already known on this topicMany infectious diseases present an environmental pattern in their incidence.Environmental factors, such as climate and weather condition, could drive the space and time correlations of infectious diseases, including influenza.Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be transmitted through aerosols, large droplets, or direct contact with secretions (or fomites) as influenza virus can.Little is known about environmental pattern in COVID-19 incidence.What this study addsThe significant association between COVID-19 daily incidence and temperature was confirmed, using 3 methods, based on the data on COVID-19 and weather from 31 provincial-level regions in mainland China.Environmental factors were considered on the basis of SEIR model, and a modified susceptible-exposed-infectious-recovered (M-SEIR) model was developed.Simulations of the COVID-19 outbreak in Wuhan presented similar effects of temperature on incidence as the incidence decrease with the increase of temperature.


2019 ◽  
Vol 49 ◽  
pp. 148-149
Author(s):  
Javakhadze R. ჯავახაძე რ. ◽  
Turmanauli M. თურმანაული მ. ◽  
Kverenchkhiladze R. კვერენჩხილაძე რ. ◽  
Chikovani A. ჩიქოვანი ა. ◽  
Arabidze M. არაბიძე მ. ◽  
...  

One of the actual global problems of mankind is an environmental pollution and its negative impact on a population’s health, that is the basis of existence of each human being and the entire state. The purpose of this article is to inform the public about the environmental factors affecting human health and its causes.As there is significant rise of ecological diseases, in many countries worldwide during the last years a great attention is paid to the legal side of environmental protection. Public well being is determined by ensuring its sanitaryepidemiological conditions,safe environment and disease prevention.


Coatings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1203
Author(s):  
Elżbieta Stanaszek-Tomal

The ability of microorganisms to degrade building materials depends on several factors. Biological corrosion occurs in close dependence with chemical and physical factors affecting microorganisms. The growth and development of microorganisms is stimulated by external stimuli, i.e., environmental factors. Microorganisms have a relatively large tolerance range for changes in environmental conditions. Under the right conditions, microorganisms thrive very well. The adverse effects may cause the inhibition of cell growth, damage, or lead to the death of the microorganism. Considering the impact of environmental factors on microorganisms, it is not possible to identify the most important of them. The result effect of overlapping factors determines the possibility of the growth of certain microorganisms. The main factors affecting the growth are temperature, humidity, hydrogen ion concentration in the environment, oxidoreductive potential, water activity in the environment, and hydrostatic pressure. This article provides a comprehensive overview of the factors causing biodeterioration. The influence of external/internal environment on the surface of cultural monuments made of mineral building materials, i.e., stone, concrete, mortar, etc., is presented.


2022 ◽  
Author(s):  
Elmakki AMIRI ◽  
Abderrahim El KARFA

It is worth pointing out that learning a foreign language in a multicultural context is a long and complex undertaking. Several factors influence whether or not English as a Foreign Language (EFL) students can accurately perceive and produce the foreign language. These variables can potentially contribute to the success and, or failure in learning and acquiring a foreign language. Given the Moroccan educational system, the research provided minimal insight into the relationship between those factors and language achievement. The present study’s aim, therefore, was to investigate the environmental factors that affect students’ academic performance. It also aimed to find out how these variables affect students’ academic achievements. To achieve this aim, data have been collected via open-ended questionnaires, and interviews addressed mainly to First Year Students of Master Programs, Department of English, FLDM, USMBA-Fez. The findings have shown that students’ academic achievements were significantly positively/negatively linked with the environmental factors, namely societal, home/family and school/classroom variables. The findings also revealed that the more highly sophisticated the social environment is, the more likely it is to foster EFL students’ academic achievements. In addition, the more similarity exists between the students’ cultures, the more successful the learning is. This study also showed that the development of EFL proficiency is a product of contextual factors influence. As such, the study concludes with several implications that brought up for possible effective change in the future to enhance the learning environment atmosphere, boost students’ academic achievements, and, therefore, achieve better results.


2014 ◽  
Vol 80 (17) ◽  
pp. 5427-5438 ◽  
Author(s):  
Denys Muzyka ◽  
Mary Pantin-Jackwood ◽  
Borys Stegniy ◽  
Oleksandr Rula ◽  
Vitaliy Bolotin ◽  
...  

ABSTRACTDespite the existence of 10 avian paramyxovirus (APMV) serotypes, very little is known about the distribution, host species, and ecological factors affecting virus transmission. To better understand the relationship among these factors, we conducted APMV wild bird surveillance in regions of Ukraine suspected of being intercontinental (north to south and east to west) flyways. Surveillance for APMV was conducted in 6,735 wild birds representing 86 species and 8 different orders during 2006 to 2011 through different seasons. Twenty viruses were isolated and subsequently identified as APMV-1 (n= 9), APMV-4 (n= 4), APMV-6 (n= 3), and APMV-7 (n= 4). The highest isolation rate occurred during the autumn migration (0.61%), with viruses isolated from mallards, teals, dunlins, and a wigeon. The rate of isolation was lower during winter (December to March) (0.32%), with viruses isolated from ruddy shelducks, mallards, white-fronted geese, and a starling. During spring migration, nesting, and postnesting (April to August) no APMV strains were isolated out of 1,984 samples tested. Sequencing and phylogenetic analysis of four APMV-1 and two APMV-4 viruses showed that one APMV-1 virus belonging to class 1 was epidemiologically linked to viruses from China, three class II APMV-1 viruses were epidemiologically connected with viruses from Nigeria and Luxembourg, and one APMV-4 virus was related to goose viruses from Egypt. In summary, we have identified the wild bird species most likely to be infected with APMV, and our data support possible intercontinental transmission of APMVs by wild birds.


2017 ◽  
Vol 12 (2) ◽  
pp. 100-111
Author(s):  
Mohammad Islam ◽  
Dulal Chandra Pattak

Abstract It goes without saying that Garments industry of Bangladesh has drawn a special attention to the mass people in the world because of being both cost leader and quality leader at the same time. The purpose of this research paper is to analyze the garments industry in Bangladesh which is going to be an emerging tiger in the world economy. It also aims to assess the impact of macro-environmental factors affecting the industry by PESTEL analysis. Again, five forces model has been analyzed to assess the impacts of competitive external factors on the Garments industry in Bangladesh. Furthermore, Garments sector competitive responses to the primary issues affecting the industry have been evaluated here. It also outlines the primary external influences to which this industry is subject. In this case, SWOT analysis has been conducted to assess the competitive position of this industry in comparison with the global perspective. The study suggests that total export is highly correlated with the exports of garments. It also finds that there is severe lacking in the safety and security compliance, wages and compensations and code of conduct of the current organizations. Moreover, GSP facility withdrawn can impact severely on the ready made garments of Bangladesh to compete with price in the international market with China, India and Vietnam etc. The ready made garments sector of Bangladesh is enjoying cost leadership as a source of completive advantage because of cheap labor. Finally, the study would like to recommend for further improvement of garment sector in Bangladesh.


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