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1.
Limnetica ; 42(1):143-154, 2023.
Article in English | Web of Science | ID: covidwho-2309631

ABSTRACT

Bromeliad phytotelmata: the first scientometric study Bromeliads are plants predominantly found in the Neotropical Region, with high diversity of species and wide distribution. Some representatives of this family have the ability to form phytotelma environments through the accumulation of water and organic matter, serving as substrate and food for a variety of organisms. Here, a scientometric analysis was carried out to show trends in scientific work on bromeliad phytotelmata and the importance of these microcosms for the maintenance of biodiversity. The papers were analyzed using the Thomson Reuters, Scopus and Scielo databases between the years 1970 and 2021. Information was sought on the years of publications, geographic regions, countries, article design (descriptive, predictive, experimental, review), focus (ecological, biological, molecular), and ecological level of study (organism, population, community and ecosystem). South America presented the highest number of works developed with the subject and also with researchers involved. Most studies presented predictive designs focusing on community ecology. Insecta, followed by Crustacea and Anura, were the most studied groups of organisms. The results contribute to a better understanding of biodiversity in bromeliad phytotelmata, pointing out gaps and trends in research directed at these natural microcosms.

2.
Viruses ; 15(4)2023 03 30.
Article in English | MEDLINE | ID: covidwho-2298421

ABSTRACT

Brazil currently ranks second in absolute deaths by COVID-19, even though most of its population has completed the vaccination protocol. With the introduction of Omicron in late 2021, the number of COVID-19 cases soared once again in the country. We investigated in this work how lineages BA.1 and BA.2 entered and spread in the country by sequencing 2173 new SARS-CoV-2 genomes collected between October 2021 and April 2022 and analyzing them in addition to more than 18,000 publicly available sequences with phylodynamic methods. We registered that Omicron was present in Brazil as early as 16 November 2021 and by January 2022 was already more than 99% of samples. More importantly, we detected that Omicron has been mostly imported through the state of São Paulo, which in turn dispersed the lineages to other states and regions of Brazil. This knowledge can be used to implement more efficient non-pharmaceutical interventions against the introduction of new SARS-CoV variants focused on surveillance of airports and ground transportation.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , Brazil/epidemiology , Transportation , Vaccination
3.
Ann Tour Res ; 93: 103319, 2022 Mar.
Article in English | MEDLINE | ID: covidwho-2262220
4.
Viruses ; 15(1)2022 Dec 31.
Article in English | MEDLINE | ID: covidwho-2232066

ABSTRACT

The circulation of SARS-CoV-2 omicron BA.4 and BA.5 subvariants with enhanced transmissibility and capacity for immune evasion resulted in a recent pandemic wave that began in April-May of 2022. We performed a statistical phylogeographic study that aimed to define the cross-border transmission patterns of BA.4 and BA.5 at the earliest stages of virus dispersal. Our sample included all BA.4 and BA.5 sequences that were publicly available in the GISAID database through mid-May 2022. Viral dispersal patterns were inferred using maximum likelihood phylogenetic trees with bootstrap support. We identified South Africa as the major source of both BA.4 and BA.5 that migrated to other continents. By contrast, we detected no significant export of these subvariants from Europe. Belgium was identified as a major hub for BA.4 transmission within Europe, while Portugal and Israel were identified as major sources of BA.5. Western and Northern European countries exhibited the highest rates of cross-border transmission, as did several popular tourist destinations in Southern and Central/Western Europe. Our study provides a detailed map of the early dispersal patterns of two highly transmissible SARS-CoV-2 omicron subvariants at a time when there was an overall relaxation of public health measures in Europe.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , Phylogeny , COVID-19/epidemiology , Europe/epidemiology , Belgium
6.
Front Med (Lausanne) ; 9: 930380, 2022.
Article in English | MEDLINE | ID: covidwho-2043487

ABSTRACT

The year of 2021 was marked by the emergence and dispersal of a number of SARS-CoV-2 lineages, resulting in the "third wave" of COVID-19 in several countries despite the level of vaccine coverage. Soon after the first confirmed cases of COVID-19 by the Delta variant in Brazil, at least seven Delta sub-lineages emerged, including the globally spread AY.101 and AY.99.2. In this study we performed a detailed analysis of the COVID-19 scenario in Brazil from April to December 2021 by using data collected by the largest private medical diagnostic company in Latin America (Dasa), and SARS-CoV-2 genomic sequences generated by its SARS-CoV-2 genomic surveillance project (GENOV). For phylogenetic and Bayesian analysis, SARS-CoV-2 genomes available at GISAID public database were also retrieved. We confirmed that the Brazilian AY.99.2 and AY.101 were the most prevalent lineages during this period, overpassing the Gamma variant in July/August. We also estimated that AY.99.2 likely emerged a few weeks after the entry of the B.1.617.2 in the country, at some point between late April and May and rapidly spread to other countries. Despite no increased fitness described for the AY.99.2 lineage, a rapid shift in the composition of Delta SARS-CoV-2 lineages prevalence in Brazil took place. Understanding the reasons leading the AY.99.2 to become the dominant lineage in the country is important to understand the process of lineage competitions that may inform future control measures.

7.
Microb Genom ; 8(9)2022 09.
Article in English | MEDLINE | ID: covidwho-2029182

ABSTRACT

During the first semester of 2021, all of Brazil has suffered an intense wave of COVID-19 associated with the Gamma variant. In July, the first cases of Delta variant were detected in the state of Rio de Janeiro. In this work, we have employed phylodynamic methods to analyse more than 1 600 genomic sequences of Delta variant collected until September in Rio de Janeiro to reconstruct how this variant has surpassed Gamma and dispersed throughout the state. After the introduction of Delta, it has initially spread mostly in the homonymous city of Rio de Janeiro, the most populous of the state. In a second stage, dispersal occurred to mid- and long-range cities, which acted as new close-range hubs for spread. We observed that the substitution of Gamma by Delta was possibly caused by its higher viral load, a proxy for transmissibility. This variant turnover prompted a new surge in cases, but with lower lethality than was observed during the peak caused by Gamma. We reason that high vaccination rates in the state of Rio de Janeiro were possibly what prevented a higher number of deaths.


Subject(s)
COVID-19 , SARS-CoV-2 , Brazil/epidemiology , COVID-19/epidemiology , Humans , SARS-CoV-2/genetics
8.
Biogeosciences ; 19(17):4089-4105, 2022.
Article in English | ProQuest Central | ID: covidwho-2025103

ABSTRACT

Contrary to most soils, permafrost soils have the atypical feature of being almost entirely deprived of soil fauna. Abiotic constraints on the fate of permafrost carbon after thawing are increasingly understood, but biotic constraints remain scarcely investigated. Incubation studies, essential to estimate effects of permafrost thaw on carbon cycling, typically measure the consequences of permafrost thaw in isolation from the topsoil and thus do not account for the effects of altered biotic interactions because of e.g. colonization by soil fauna. Microarthropods facilitate the dispersal of microorganisms in soil, both on their cuticle (ectozoochory) and through their digestive tract (endozoochory), which may be particularly important in permafrost soils, considering that microbial community composition can strongly constrain permafrost biogeochemical processes.Here we tested how a model species of microarthropod (the CollembolaFolsomia candida) affected aerobic CO2 production of permafrost soil over a 25 d incubation. By using Collembola stock cultures grown on permafrost soil or on an arctic topsoil, we aimed to assess the potential for endo- and ectozoochory of soil bacteria, while cultures grown on gypsum and sprayed with soil suspensions would allow the observation of only ectozoochory.The presence of Collembola introduced bacterial amplicon sequence variants (ASVs) absent in the no-Collembola control, regardless of their microbiome manipulation, when considering presence–absence metrics (unweighted UniFrac metrics), which resulted in increased species richness. However, these introduced ASVs did not induce changes in bacterial community composition as a whole (accounting for relative abundances, weighted UniFrac), which might only become detectable in the longer term.CO2 production was increased by 25.85 % in the presence of Collembola, about half of which could be attributed to Collembola respiration based on respiration rates measured in the absence of soil. We argue that the rest of the CO2 being respired can be considered a priming effect of the presence of Collembola, i.e. a stimulation of permafrost CO2 production in the presence of active microarthropod decomposers. Overall, our findings underline the importance of biotic interactions in permafrost biogeochemical processes and the need to explore the additive or interactive effects of other soil food web groups of which permafrost soils are deprived.

9.
Viruses ; 14(8)2022 07 27.
Article in English | MEDLINE | ID: covidwho-1969493

ABSTRACT

In the present study, we provide a retrospective genomic surveillance of the SARS-CoV-2 pandemic in Lebanon; we newly sequence the viral genomes of 200 nasopharyngeal samples collected between July 2020 and February 2021 from patients in different regions of Lebanon and from travelers crossing the Lebanese-Syrian border, and we also analyze the Lebanese genomic dataset available at GISAID. Our results show that SARS-CoV-2 infections in Lebanon during this period were shaped by the turnovers of four dominant SARS-CoV-2 lineages, with B.1.398 being the first to thoroughly dominate. Lebanon acted as a dispersal center of B.1.398 to other countries, with intercontinental transmissions being more common than within-continent. Within the country, the district of Tripoli, which was the source of 43% of the total B.1.398 sequences in our study, was identified as being an important source of dispersal in the country. In conclusion, our findings exemplify the butterfly effect, by which a lineage that emerges in a small area can be spread around the world, and highlight the potential role of developing countries in the emergence of new variants.


Subject(s)
COVID-19 , COVID-19/epidemiology , Humans , Lebanon/epidemiology , Pandemics , Retrospective Studies , SARS-CoV-2/genetics
10.
Revista Peruana de Biologia ; 29(1):1-10, 2022.
Article in English | ProQuest Central | ID: covidwho-1811588

ABSTRACT

Future research should prioritize both the preservation of ecological processes and the understanding of the negative effects of human impacts on local biodiversity. Unfortunately, Western Ecuador has suffered several environmental problems over a prolonged period, such as deforestation, illegal hunting, and rapid change in land use (Dodson & Gentry 1991, Parker & Carr 1992), causing declines in mammalian species. [...]the loss of large herbivores affects seed dispersal and recruitment, the loss of carnivores decreases predatory activity and nutrient recycling, and the decline of other mammalian species impacts pollination (Rumiz 2010). [...]to aid in mammal management and conservation, it is important to document current species richness and evaluate potential threats (Cervera et al. 2016, Lizcano et al. 2016). [...]there are 21 protected areas that include coastal-marine landscapes, mangroves, the humid forest of Chocó, and Tumbesian dry forests (MAE 2015).

11.
J Hosp Infect ; 123: 52-60, 2022 May.
Article in English | MEDLINE | ID: covidwho-1757533

ABSTRACT

BACKGROUND: Meticillin-resistant Staphylococcus aureus (MRSA) infections are rampant in hospitals and residential care homes for the elderly (RCHEs). AIM: To analyse the prevalence of MRSA colonization among residents and staff, and degree of environmental contamination and air dispersal of MRSA in RCHEs. METHODS: Epidemiological and genetic analysis by whole-genome sequencing (WGS) in 12 RCHEs in Hong Kong. FINDINGS: During the COVID-19 pandemic (from September to October 2021), 48.7% (380/781) of RCHE residents were found to harbour MRSA at any body site, and 8.5% (8/213) of staff were nasal MRSA carriers. Among 239 environmental samples, MRSA was found in 39.0% (16/41) of randomly selected resident rooms and 31.3% (62/198) of common areas. The common areas accessible by residents had significantly higher MRSA contamination rates than those that were not accessible by residents (37.2%, 46/121 vs. 22.1%, 17/177, P=0.028). Of 124 air samples, nine (7.3%) were MRSA-positive from four RCHEs. Air dispersal of MRSA was significantly associated with operating indoor fans in RCHEs (100%, 4/4 vs. 0%, 0/8, P=0.002). WGS of MRSA isolates collected from residents, staff and environmental and air samples showed that ST 1047 (CC1) lineage 1 constituted 43.1% (66/153) of all MRSA isolates. A distinctive predominant genetic lineage of MRSA in each RCHE was observed, suggestive of intra-RCHE transmission rather than clonal acquisition from the catchment hospital. CONCLUSION: MRSA control in RCHEs is no less important than in hospitals. Air dispersal of MRSA may be an important mechanism of dissemination in RCHEs with operating indoor fans.


Subject(s)
COVID-19 , Methicillin-Resistant Staphylococcus aureus , Staphylococcal Infections , Aged , COVID-19/epidemiology , Carrier State/epidemiology , Humans , Methicillin , Methicillin-Resistant Staphylococcus aureus/genetics , Pandemics , Staphylococcal Infections/epidemiology
12.
J Med Virol ; 94(6): 2414-2421, 2022 06.
Article in English | MEDLINE | ID: covidwho-1669580

ABSTRACT

As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) evolves, it accumulates mutations, which are changes in the genetic code. Because this virus has built-in RNA repair mechanisms, it generates mutations more slowly than some other RNA viruses. Thousands of mutations have emerged since the beginning of the pandemic throughout all virus genomes sequenced to date, resulting in thousands of distinct variants. However, some variants have recently been discovered that appear to increase transmissibility and may affect illness pervasiveness. In this study, we investigated SARS-CoV-2 variants and how countries intervene with them. We also depicted the top 25 countries where the Omicron variant is prevalent, with the UK, US, Denmark, France, and Australia having the top five places as of January 13, 2022. The perception of SARS-CoV-2 variants was investigated in those five countries, and the propagation rate of the Omicron variant was determined to be 51%, 29%, 26%, 15%, and 44%, respectively, indicating that the Omicron variant is the most prevalent among the others. Then, a study of SARS-CoV-2 infection test rate based on tests conducted per one million populations with a number of sequences in those five countries reveals that 25%, 73%, 1.6%, 4.8%, and 1.5%, respectively, it suggests that viral testing should be increased in all five countries since it will help to determine the precise distribution of variants and aid governments in making policy decisions for public safety. We anticipated the production of new variants strains. This study implies that limiting disease transmissions, such as acquiring a coronavirus disease 2019 vaccine and booster doses for those aged 18 and older, as well as wearing the mask in public places, is the best strategy to prevent the emergence of new variants.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiology , COVID-19 Vaccines , Humans , Pandemics , SARS-CoV-2/genetics
13.
Geological Magazine ; 159(2):177-178, 2022.
Article in English | ProQuest Central | ID: covidwho-1627071

ABSTRACT

[...]a model of palaeo-flow dynamics, sediment dispersal pattern, depositional setting, cyclicity pattern and basin tectonics is put forward. [...]they suggest that the younger 40Ar/39Ar, Rb–Sr and U–Pb ages in the Kaladgi and Bhima basins could reflect the timing of post-depositional alteration events. [...]of the presence of terrigenous material within the stromatolites, whole-rock geochemical analyses for trace elements and rare earth elements cannot be used for interpretation of seawater chemistry and the redox conditions of the time.

14.
IEEE Open J Eng Med Biol ; 2: 26-35, 2021.
Article in English | MEDLINE | ID: covidwho-1599005

ABSTRACT

The SARS-CoV-2 virus is primarily transmitted through virus-laden fluid particles ejected from the mouth of infected people. Face covers can mitigate the risk of virus transmission but their outward effectiveness is not fully ascertained. Objective: by using a background oriented schlieren technique, we aim to investigate the air flow ejected by a person while quietly and heavily breathing, while coughing, and with different face covers. Results: we found that all face covers without an outlet valve reduce the front flow through by at least 63% and perhaps as high as 86% if the unfiltered cough jet distance was resolved to the anticipated maximum distance of 2-3 m. However, surgical and handmade masks, and face shields, generate significant leakage jets that may present major hazards. Conclusions: the effectiveness of the masks should mostly be considered based on the generation of secondary jets rather than on the ability to mitigate the front throughflow.

15.
Comput Human Behav ; 127: 107059, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1525722

ABSTRACT

On the basis of parasite-stress theory of sociality and behavioral immune system theory, this research examined how concerns regarding the Coronavirus disease 2019 (COVID-19) in cyberspace (i.e., online search volume for coronavirus-related keywords) would predict human reduced dispersal in the real world (i.e., human mobility trends throughout the pandemic) between January 05, 2020 and May 22, 2021. Multiple regression analyses controlling for COVID-19 cases per million, case fatality rate, death-thought accessibility, government stringency index, yearly trends, season, religious holidays, and reduced dispersal in the preceding week were conducted. Meta-regression analysis of the multiple regression results showed that when there were high levels of COVID-19 concerns in cyberspace in a given week, the amount of time people spent at home increased from the previous week across American states (Study 1) and 115 countries/territories (Study 2). Across studies, the associations between COVID-19 concerns and reduced dispersal were stronger in areas of higher historical risks of infectious-disease contagion. Compared with actual coronavirus threat, COVID-19 concerns in cyberspace had significantly larger effects on predicting human reduced dispersal in the real world. Thus, online query data have invaluable implications for predicting large-scale behavioral changes in response to life-threatening events in the real world and are indispensable for COVID-19 surveillance.

16.
Front Public Health ; 8: 551836, 2020.
Article in English | MEDLINE | ID: covidwho-1207721

Subject(s)
COVID-19 , Humans , SARS-CoV-2
17.
PeerJ ; 9: e11036, 2021.
Article in English | MEDLINE | ID: covidwho-1136628

ABSTRACT

We test the hypothesis that the tree species previously known as Deinbollia sp. 2. is a new species for science. We formally characterise and name this species as Deinbollia onanae (Sapindaceae-Litchi clade) and we discuss it in the context of the assemblage of montane tree species in the Cameroon Highlands of West-Central Africa. The new species is a shade-bearing, non-pioneer understorey forest tree species reaching 15 m high and a trunk diameter that can attain over 40 cm at 1.3 m above the ground. Seed dispersal has been recorded by chimpanzees (Pan troglodytes ellioti) and by putty-nose monkeys (Cercopithecus nictitans) and the species is used by chimpanzees for nesting. Cameroon has the highest species-diversity and species endemism known in this African-Western Indian Ocean genus of 42, mainly lowland species. Deinbollia onanae is an infrequent tree species known from six locations in surviving islands of montane (sometimes also upper submontane) forest along the line of the Cameroon Highlands, including one at Ngel Nyaki in Mambilla, Nigeria. Deinbollia onanae is here assessed as Endangered according to the IUCN 2012 standard, threatened by severe fragmentation of its mountain forest habitat due to extensive and ongoing clearance for agriculture. The majority of the 28 tree species of montane forest (above 2000 m alt.) in the Cameroon Highlands are also widespread in East African mountains (i.e. are Afromontane wide). Deinbollia onanae is one of only seven species known to be endemic (globally restricted to) these highlands. It is postulated that this new species is morphologically closest to Deinbollia oreophila, a frequent species at a lower (submontane) altitudinal band of the same range. Detailed ecological data on Deinbollia onanae from the Nigerian location, Ngel Nyaki, where it has been known under the name Deinbollia "pinnata", is reviewed.

18.
Adv Colloid Interface Sci ; 290: 102400, 2021 Apr.
Article in English | MEDLINE | ID: covidwho-1116130

ABSTRACT

We review concepts involved in describing the chemodynamic features of nanoparticles and apply the framework to gain physicochemical insights into interactions between SARS-CoV-2 virions and airborne particulate matter (PM). Our analysis is highly pertinent given that the World Health Organisation acknowledges that SARS-CoV-2 may be transmitted by respiratory droplets, and the US Center for Disease Control and Prevention recognises that airborne transmission of SARS-CoV-2 can occur. In our theoretical treatment, the virion is assimilated to a core-shell nanoparticle, and contributions of various interaction energies to the virion-PM association (electrostatic, hydrophobic, London-van der Waals, etc.) are generically included. We review the limited available literature on the physicochemical features of the SARS-CoV-2 virion and identify knowledge gaps. Despite the lack of quantitative data, our conceptual framework qualitatively predicts that virion-PM entities are largely able to maintain equilibrium on the timescale of their diffusion towards the host cell surface. Comparison of the relevant mass transport coefficients reveals that virion biointernalization demand by alveolar host cells may be greater than the diffusive supply. Under such conditions both the free and PM-sorbed virions may contribute to the transmitted dose. This result points to the potential for PM to serve as a shuttle for delivery of virions to host cell targets. Thus, our critical review reveals that the chemodynamics of virion-PM interactions may play a crucial role in the transmission of COVID-19, and provides a sound basis for explaining reported correlations between episodes of air pollution and outbreaks of COVID-19.


Subject(s)
COVID-19/transmission , Epithelial Cells/virology , Particulate Matter/chemistry , SARS-CoV-2/chemistry , Virion/chemistry , Aerosols , Biomechanical Phenomena , COVID-19/virology , Diffusion , Humans , Hydrophobic and Hydrophilic Interactions , Models, Chemical , Nanoparticles/chemistry , Pulmonary Alveoli/virology , SARS-CoV-2/metabolism , SARS-CoV-2/pathogenicity , Static Electricity , Virion/metabolism , Virion/pathogenicity , Virus Internalization , Water/chemistry
19.
PeerJ ; 9: e10690, 2021.
Article in English | MEDLINE | ID: covidwho-1029596

ABSTRACT

The Asian giant hornet (AGH, Vespa mandarinia) is the world's largest hornet, occurring naturally in the Indomalayan region, where it is a voracious predator of pollinating insects including honey bees. In September 2019, a nest of Asian giant hornets was detected outside of Vancouver, British Columbia; multiple individuals were detected in British Columbia and Washington state in 2020; and another nest was found and eradicated in Washington state in November 2020, indicating that the AGH may have successfully wintered in North America. Because hornets tend to spread rapidly and become pests, reliable estimates of the potential invasive range of V. mandarinia in North America are needed to assess likely human and economic impacts, and to guide future eradication attempts. Here, we assess climatic suitability for AGH in North America, and suggest that, without control, this species could establish populations across the Pacific Northwest and much of eastern North America. Predicted suitable areas for AGH in North America overlap broadly with areas where honey production is highest, as well as with species-rich areas for native bumble bees and stingless bees of the genus Melipona in Mexico, highlighting the economic and environmental necessity of controlling this nascent invasion.

20.
Viruses ; 12(12)2020 11 25.
Article in English | MEDLINE | ID: covidwho-945954

ABSTRACT

Since the recent epidemics of yellow fever in Angola and Brazil as well as the importation of cases to China in 2016, there has been an increased interest in the century-old enigma, absence of yellow fever in Asia. Although this topic has been repeatedly reviewed before, the history of human intervention has never been considered a critical factor. A two-stage literature search online for this review, however, yielded a rich history indispensable for the debate over this medical enigma. As we combat the pandemic of COVID-19 coronavirus worldwide today, we can learn invaluable lessons from the historical events in Asia. In this review, I explore the history first and then critically examine in depth major hypotheses proposed in light of accumulated data, global dispersal of the principal vector, patterns of YF transmission, persistence of urban transmission, and the possibility of YF in Asia. Through this process of re-examination of the current knowledge, the subjects for research that should be conducted are identified. This review also reveals the importance of holistic approach incorporating ecological and human factors for many unresolved subjects, such as the enigma of YF absence in Asia, vector competence, vector dispersal, spillback, viral persistence and transmission mechanisms.


Subject(s)
Aedes/physiology , Mosquito Vectors/physiology , Yellow Fever/prevention & control , Yellow Fever/transmission , Aedes/virology , Animal Distribution , Animals , Asia , Humans , Mosquito Vectors/virology , Yellow fever virus
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