scholarly journals SARS-CoV-2 lineage dynamics in England from September to November 2021: high diversity of Delta sub-lineages and increased transmissibility of AY.4.2

2021 ◽  
Author(s):  
Oliver Eales ◽  
Andrew Page ◽  
Leonardo de Oliveira Martins ◽  
Haowei Wang ◽  
Barbara Bodinier ◽  
...  
Keyword(s):  
Mutation Rate ◽  
Immune Escape ◽  
Evolutionary Rate ◽  
Reproduction Number ◽  
Natural Infection ◽  
Community Sample ◽  
Rt Pcr ◽  
Slowing Down ◽  
Routine Surveillance ◽  
Community Transmission

Since the emergence of SARS-CoV-2, evolutionary pressure has driven large increases in the transmissibility of the virus. However, with increasing levels of immunity through vaccination and natural infection the evolutionary pressure will switch towards immune escape. Here we present phylogenetic relationships and lineage dynamics within England (a country with high levels of immunity), as inferred from a random community sample of individuals who provided a self-administered throat and nose swab for rt-PCR testing as part of the REal-time Assessment of Community Transmission-1 (REACT-1) study. From 9 to 27 September 2021 (round 14) and 19 October to 5 November 2021 (round 15), all lineages sequenced within REACT-1 were Delta or a Delta sub-lineage with 44 unique lineages identified. The proportion of the original Delta variant (B.1.617.2) was found to be increasing between September and November 2021, which may reflect an increasing number of sub-lineages which have yet to be identified. The proportion of B.1.617.2 was greatest in London, which was further identified as a region with an increased level of genetic diversity. The Delta sub-lineage AY.4.2 was found to be robustly increasing in proportion, with a reproduction number 15% (8%, 23%) greater than its parent and most prevalent lineage, AY.4. Both AY.4.2 and AY.4 were found to be geographically clustered in September but this was no longer the case by late October/early November, with only the lineage AY.6 exhibiting clustering towards the South of England. Though no difference in the viral load based on cycle threshold (Ct) values was identified, a lower proportion of those infected with AY.4.2 had symptoms for which testing is usually recommend (loss or change of sense of taste, loss or change of sense of smell, new persistent cough, fever), compared to AY.4 (p = 0.026). The evolutionary rate of SARS-CoV-2, as measured by the mutation rate, was found to be slowing down during the study period, with AY.4.2 further found to have a reduced mutation rate relative to AY.4. As SARS-CoV-2 moves towards endemicity and new variants emerge, genomic data obtained from random community samples can augment routine surveillance data without the potential biases introduced due to higher sampling rates of symptomatic individuals.

scholarly journals SARS-CoV-2 lineage dynamics in England from January to March 2021 inferred from representative community samples

2021 ◽  
Author(s):  
Oliver Eales ◽  
Andrew Page ◽  
Sonja N. Tang ◽  
Caroline E. Walters ◽  
Haowei Wang ◽  
...  
Keyword(s):  
Reproduction Number ◽  
Sequence Data ◽  
Community Sample ◽  
Age Groups ◽  
Health Interventions ◽  
Wild Type ◽  
Rt Pcr ◽  
Community Surveys ◽  
Community Transmission ◽  
Middle Aged Adults

Genomic surveillance for SARS-CoV-2 lineages informs our understanding of possible future changes in transmissibility and vaccine efficacy. However, small changes in the frequency of one lineage over another are often difficult to interpret because surveillance samples are obtained from a variety of sources. Here, we describe lineage dynamics and phylogenetic relationships using sequences obtained from a random community sample who provided a throat and nose swab for rt-PCR during the first three months of 2021 as part of the REal-time Assessment of Community Transmission-1 (REACT-1) study. Overall, diversity decreased during the first quarter of 2021, with the B.1.1.7 lineage (first identified in Kent) predominant, driven by a 0.3 unit higher reproduction number over the prior wild type. During January, positive samples were more likely B.1.1.7 in younger and middle-aged adults (aged 18 to 54) than in other age groups. Although individuals infected with the B.1.1.7 lineage were no more likely to report one or more classic COVID-19 symptoms compared to those infected with wild type, they were more likely to be antibody positive 6 weeks after infection. Viral load was higher in B.1.1.7 infection as measured by cycle threshold (Ct) values, but did not account for the increased rate of testing positive for antibodies. The presence of infections with non-imported B.1.351 lineage (first identified in South Africa) during January, but not during February or March, suggests initial establishment in the community followed by fade-out. However, this occurred during a period of stringent social distancing and targeted public health interventions and does not immediately imply similar lineages could not become established in the future. Sequence data from representative community surveys such as REACT-1 can augment routine genomic surveillance.

scholarly journals Fernando de Noronha: how an island controlled the community transmission of COVID-19 in Brazil

2020 ◽  
Author(s):  
Mozart Júlio Tabosa Sales ◽  
Ligia Regina Franco Sansigolo Kerr ◽  
Regina Vianna Brizolara ◽  
Ivana Cristina de Holanda Cunha Barreto ◽  
Rosa Lívia Freitas de Almeida ◽  
...  
Keyword(s):  
Public Health ◽  
Cohort Study ◽  
Food Insecurity ◽  
Control Measures ◽  
Prevention Measures ◽  
Rt Pcr ◽  
Routine Surveillance ◽  
Essential Services ◽  
Fernando De Noronha ◽  
Community Transmission

AbstractIntroductionFernando Noronha (FNA) is a small Brazilian archipelago in the Atlantic, part of the state of Pernambuco that COVID-19 has decimated. Anticipating the worst from the pandemic, Island and state authorities implemented a series of public health actions to contain the epidemic. This paper, reporting the results of the first wave of a cohort study, documents the measures and their effects through a cohort study.MethodsMeasures were documented at the time of implementation. A random sample of 904 residents were selected from the health register, interviewed and tested for COVID-19 (RT-PCR and serology). The survey explored socioeconomic variables and adherence to prevention behaviors.ResultsFlights were reduced from 38 to once a week, FNA was closed to tourism, schools were closed, and testing and tracing contacts was mandated along with social distancing and use of masks. A household lockdown was briefly imposed for residents. A prevalence of 5.1% was found, and a total of 158 cases of COVID-19 was estimated, although only 28 had been reported in routine surveillance. Half of the population reported food insecurity and applied for government COVID-19 benefits. Adherence to control measures was high, except for intrahousehold mask use with family and friends.ConclusionDespite high levels of COVID-19 in Pernambuco, continued exposure through the provision of essential services from the mainland, and lack of direction from national authorities, FNA was able to implement a series of prevention measures unique in Brazil that contained the epidemic on the island.

An Updated Review on COVID-19

2020 ◽  
Vol 20 ◽  
Author(s):  
Mahmoud Ahmed Ebada ◽  
Ahmed Wadaa Allah ◽  
Eshak Bahbah ◽  
Ahmed Negida
Keyword(s):  
Screening Tool ◽  
Distress Syndrome ◽  
Reproduction Number ◽  
Case Fatality ◽  
Current Data ◽  
Future Research ◽  
Rt Pcr ◽  
Viral Structure ◽  
Discharge Criteria ◽  
Serology Testing

: Coronavirus Disease (COVID-19) pandemic has affected more than seven million individuals in 213 countries worldwide with a basic reproduction number ranging from 1.5 to 3.5 and an estimated case fatality rate ranging from 2% to 7%. A substantial proportion of COVID-19 patients are asymptomatic; however, symptomatic cases might present with fever, cough, and dyspnoea or severe symptoms up to acute respiratory distress syndrome. Currently, RNA RT-PCR is the screening tool, while bilateral chest CT is the confirmatory clinical diagnostic test. Several drugs have been repurposed to treat COVID-19, including chloroquine or hydroxychloroquine with or without azithromycin, lopinavir/ritonavir combination, remdesivir, favipiravir, tocilizumab, and EIDD-1931. Recently, Remdesivir gained FDA emergency approval based on promising early findings from the interim analysis of 1063 patients. The recently developed serology testing for SARSCoV-2 antibodies opened the door to evaluate the actual burden of the disease and to determine the rate of the population who have been previously infected (or developed immunity). This review article summarizes current data on the COVID-19 pandemic starting from the early outbreak, viral structure and origin, pathogenesis, diagnosis, treatment, discharge criteria, and future research.

scholarly journals Molecular epidemiology of coxsackievirus A16 circulating in children in Beijing, China from 2010 to 2019

2021 ◽  
Author(s):  
Ya-Fang Hu ◽  
Li-Ping Jia ◽  
Fang-Yuan Yu ◽  
Li-Ying Liu ◽  
Qin-Wei Song ◽  
...  
Keyword(s):  
Molecular Epidemiology ◽  
Evolutionary Rate ◽  
Foot And Mouth Disease ◽  
Recent Common Ancestor ◽  
Rt Pcr ◽  
Coxsackievirus A16 ◽  
Most Recent Common Ancestor ◽  
Etiological Agents ◽  
High Level ◽  
And Control

Abstract Background Coxsackievirus A16 (CVA16) is one of the major etiological agents of hand, foot and mouth disease (HFMD). This study aimed to investigate the molecular epidemiology and evolutionary characteristics of CVA16. Methods Throat swabs were collected from children with HFMD and suspected HFMD during 2010–2019. Enteroviruses (EVs) were detected and typed by real-time reverse transcription-polymerase chain reaction (RT-PCR) and RT-PCR. The genotype, evolutionary rate, the most recent common ancestor, population dynamics and selection pressure of CVA16 were analyzed based on viral protein gene (VP1) by bioinformatics software. Results A total of 4709 throat swabs were screened. EVs were detected in 3180 samples and 814 were CVA16 positive. More than 81% of CVA16-positive children were under 5 years old. The prevalence of CVA16 showed obvious periodic fluctuations with a high level during 2010–2012 followed by an apparent decline during 2013–2017. However, the activities of CVA16 increased gradually during 2018–2019. All the Beijing CVA16 strains belonged to sub-genotype B1, and B1b was the dominant strain. One B1c strain was detected in Beijing for the first time in 2016. The estimated mean evolutionary rate of VP1 gene was 4.49 × 10–3 substitution/site/year. Methionine gradually fixed at site-23 of VP1 since 2012. Two sites were detected under episodic positive selection, one of which (site-223) located in neutralizing linear epitope PEP71. Conclusions The dominant strains of CVA16 belonged to clade B1b and evolved in a fast evolutionary rate during 2010–2019 in Beijing. To provide more favorable data for HFMD prevention and control, it is necessary to keep attention on molecular epidemiological and evolutionary characteristics of CVA16.

scholarly journals The effects of non-pharmaceutical interventions on SARS-CoV-2 transmission in different socioeconomic populations in Kuwait: a modeling study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Fatima Khadadah ◽  
Abdullah A. Al-Shammari ◽  
Ahmad Alhashemi ◽  
Dari Alhuwail ◽  
Bader Al-Saif ◽  
...  
Keyword(s):  
Disease Transmission ◽  
Reproduction Number ◽  
Transmission Model ◽  
Socioeconomic Groups ◽  
Before And After ◽  
Cross Transmission ◽  
Community Transmission ◽  
The Impact ◽  
Pharmaceutical Interventions ◽  
The Basic Reproduction Number

Abstract Background Aggressive non-pharmaceutical interventions (NPIs) may reduce transmission of SARS-CoV-2. The extent to which these interventions are successful in stopping the spread have not been characterized in countries with distinct socioeconomic groups. We compared the effects of a partial lockdown on disease transmission among Kuwaitis (P1) and non-Kuwaitis (P2) living in Kuwait. Methods We fit a modified metapopulation SEIR transmission model to reported cases stratified by two groups to estimate the impact of a partial lockdown on the effective reproduction number ($$ {\mathcal{R}}_e $$ R e ). We estimated the basic reproduction number ($$ {\mathcal{R}}_0 $$ R 0 ) for the transmission in each group and simulated the potential trajectories of an outbreak from the first recorded case of community transmission until 12 days after the partial lockdown. We estimated $$ {\mathcal{R}}_e $$ R e values of both groups before and after the partial curfew, simulated the effect of these values on the epidemic curves and explored a range of cross-transmission scenarios. Results We estimate $$ {\mathcal{R}}_e $$ R e at 1·08 (95% CI: 1·00–1·26) for P1 and 2·36 (2·03–2·71) for P2. On March 22nd, $$ {\mathcal{R}}_e $$ R e for P1 and P2 are estimated at 1·19 (1·04–1·34) and 1·75 (1·26–2·11) respectively. After the partial curfew had taken effect, $$ {\mathcal{R}}_e $$ R e for P1 dropped modestly to 1·05 (0·82–1·26) but almost doubled for P2 to 2·89 (2·30–3·70). Our simulated epidemic trajectories show that the partial curfew measure greatly reduced and delayed the height of the peak in P1, yet significantly elevated and hastened the peak in P2. Modest cross-transmission between P1 and P2 greatly elevated the height of the peak in P1 and brought it forward in time closer to the peak of P2. Conclusion Our results indicate and quantify how the same lockdown intervention can accentuate disease transmission in some subpopulations while potentially controlling it in others. Any such control may further become compromised in the presence of cross-transmission between subpopulations. Future interventions and policies need to be sensitive to socioeconomic and health disparities.

scholarly journals First Report of Natural Infection of Penstemon acuminatus with Cucumber mosaic virus in the Treasure Valley Region of Idaho and Oregon

Plant Disease ◽  
2009 ◽  
Vol 93 (7) ◽  
pp. 762-762 ◽  
Author(s):  
R. K. Sampangi ◽  
C. Almeyda ◽  
K. L. Druffel ◽  
S. Krishna Mohan ◽  
C. C. Shock ◽  
...  
Keyword(s):  
Cucumber Mosaic Virus ◽  
Mosaic Virus ◽  
Great Basin ◽  
Natural Infection ◽  
The United States ◽  
Native Plant ◽  
Rt Pcr ◽  
Cmv Infection ◽  
Spot Virus ◽  
First Report

Penstemons are perennials that are grown for their attractive flowers in the United States. Penstemon species (P. acuminatus, P. deustus, and P. speciosus) are among the native forbs considered as a high priority for restoration of great basin rangelands. During the summer of 2008, symptoms of red spots and rings were observed on leaves of P. acuminatus (family Scrophulariaceae) in an experimental trial in Malheur County, Oregon where the seeds from several native forbs were multiplied for restoration of range plants in intermountain areas. These plants were cultivated as part of the Great Basin Native Plant Selection and Increase Project. Several native wildflower species are grown for seed production in these experimental plots. Plants showed red foliar ringspots and streaks late in the season. Fungal or bacterial infection was ruled out. Two tospoviruses, Impatiens necrotic spot virus and Tomato spotted wilt virus, and one nepovirus, Tomato ring spot virus, are known to infect penstemon (2,3). Recently, a strain of Turnip vein-clearing virus, referred to as Penstemon ringspot virus, was reported in penstemon from Minnesota (1). Symptomatic leaves from the penstemon plants were negative for these viruses when tested by ELISA or reverse transcription (RT)-PCR. However, samples were found to be positive for Cucumber mosaic virus (CMV) when tested by a commercially available kit (Agdia Inc., Elkhart, IN). To verify CMV infection, total nucleic acid extracts from the symptomatic areas of the leaves were prepared and used in RT-PCR. Primers specific to the RNA-3 of CMV were designed on the basis of CMV sequences available in GenBank. The primer pair consisted of CMV V166: 5′ CCA ACC TTT GTA GGG AGT GA 3′ and CMV C563: 5′ TAC ACG AGG ACG GCG TAC TT 3′. An amplicon of the expected size (400 bp) was obtained and cloned and sequenced. BLAST search of the GenBank for related sequences showed that the sequence obtained from penstemon was highly identical to several CMV sequences, with the highest identity (98%) with that of a sequence from Taiwan (GenBank No. D49496). CMV from infected penstemon was successfully transmitted by mechanical inoculation to cucumber seedlings. Infection of cucumber plants was confirmed by ELISA and RT-PCR. To our knowledge, this is the first report of CMV infection of P. acuminatus. With the ongoing efforts to revegetate the intermountain west with native forbs, there is a need for a comprehensive survey of pests and diseases affecting these plants. References: (1) B. E. Lockhart et al. Plant Dis. 92:725, 2008. (2) D. Louro. Acta Hortic. 431:99, 1996. (3) M. Navalinskiene et al. Trans. Estonian Agric. Univ. 209:140, 2000.

scholarly journals Molecular Analysis and Genome Sequencing of SARS-Cov-2 during Second Wave 2021 Revealed Variant Diversity in India

2021 ◽  
Author(s):  
Rupinder Bakshi ◽  
Satinder Kaur ◽  
Karashdeep Kaur ◽  
Ramanpreet Kaur ◽  
Jaspreet Kaur Boparai ◽  
...  
Keyword(s):  
Genome Sequencing ◽  
Immune Escape ◽  
Age Group ◽  
Wild Type ◽  
Rt Pcr ◽  
Dominant Trait ◽  
Male Population ◽  
Second Wave ◽  
Rapid Emergence ◽  
Critical Challenge

SARS-CoV-2 variants rapid emergence has posed critical challenge of higher transmission and immune escape causing serious threats to control the pandemic. The present study was carried out in confirmed cases of SARS-CoV-2 patients to elucidate the prevalence of SARS-CoV-2 variant strain. We performed RT-PCR using extracted RNA from the nasopharyngeal swabs of suspected Covid-19 patients. Confirmed positive cases with CT<25 were subjected to whole-genome sequencing to track the prevalence of the virus in the Malwa region of Punjab. The presence of B.1, B.1.1.7, B.1.351, B.1.617.1, B.1.617.2, AY.1 and other unidentified variants of SARS-CoV-2 was found in the studied population. Among all the variants, B.1.1.7 (UK variant) and B.1.617.2 (delta-Indian variant) was found to be the most dominant variant in the population and was found majorly in Patiala followed by Ludhiana, SBS Nagar, Mansa and Sangrur. In addition to this, sequencing results also observed that the dominant trait was more prevalent in male population and age group 21-40 years. The B.1.1.7 and B.1.617.2 variant of SARS-CoV-2 is replacing the wild type (Wuhan Strain) and emerging as the dominant variant in Punjab.

Foxp3 in Lewis Lung Cancer Cells Enhances the Expression of TGF-β1 and IL-10

2014 ◽  
Vol 998-999 ◽  
pp. 252-255
Author(s):  
Li Song Chen ◽  
Xiao Dong Gai ◽  
Chun Li
Keyword(s):  
Lung Cancer ◽  
Immune Escape ◽  
Lewis Lung ◽  
Rt Pcr ◽  
Vector Group ◽  
Lewis Lung Cancer ◽  
Tumor Immune Escape ◽  
Empty Vector ◽  
Tgf Β1 ◽  
Empty Vector Group

In order to explore the related mechanism of Foxp3 in tumor immune escape, the study detected the expression of Foxp3 in lewis lung cancer (LLC) cells and analyzed the expression of TGF-β1 and IL-10 in Foxp3 overexpressed LLC cells. Foxp3 mRNA was detected in LLC cells by RT-PCR. Foxp3 was highly expressed in Foxp3 transfected LLC group than that of in empty vector group and LLC group by RT-PCR(P <0.01). The mRNA and protein expression of TGF-β1 and IL-10 significantly increased in Foxp3 transfected LLC group than that of in empty vector group and LLC group by RT-PCR and ELISA(P <0.05). These results suggest that Foxp3 in LLC cells may promote tumor immune escape by enhancing the expression of TGF-β1 and IL-10.

scholarly journals First Report on the Natural Occurrence of Cherry virus A in Mirabelle Plum (Prunus domestica var. insititia)

Plant Disease ◽  
2005 ◽  
Vol 89 (4) ◽  
pp. 433-433 ◽  
Author(s):  
L. Svanella-Dumas ◽  
A. Marais ◽  
P. Gentit ◽  
J. Lamorte ◽  
T. Candresse
Keyword(s):  
Natural Infection ◽  
Plant Viruses ◽  
Natural Occurrence ◽  
Prunus Domestica ◽  
Rt Pcr ◽  
Pcr Assay ◽  
First Report ◽  
Specific Pcr ◽  
Specific Pcr Assay ◽  
Prunus Spp

Cherry virus A (CVA) is a member of the Capillovirus genus (2). It was discovered serendipitously during cloning of the little cherry agent (2) and has since been shown to be relatively widespread in sweet and sour cherry (Prunus cerasus and P. avium) (2,3). It is currently unclear whether CVA is associated with any specific symptoms in these hosts. Although it can be transmitted by grafting and thus propagated in peach, it has not been reported to naturally infect any host other than cherry. Using a degenerate reverse transcription-polymerase chain reaction (RT-PCR) technique targeting a conserved region of the RNA-dependent RNA polymerase (RdRp) and allowing the amplification of members of the Trichovirus, Capillovirus, and Foveavirus genera of filamentous plant viruses (1), a number of symptomatic Prunus spp. germplasm were evaluated. Among these, a cv. Mirabelle dorée accession (Prunus domestica var. insititia P332) of French origin exhibited severe symptoms of rosetting, severe leaf and fruit deformation, and yellow mosaic occasionally turning necrotic. RT-PCR conducted on symptomatic samples produced an amplification product of the expected size (362 bp) in several independent experiments. Sequencing of these products yielded a single sequence (GenBank Accession No. AY792509) with 88.1% nucleotide identity and 93.2% amino acid identity with the type strain of CVA (2). Presence of a CVA isolate was independently confirmed using a CVA-specific PCR assay directly on the original plum material or following experimental transmission by grafting on several new hosts including apricot (P. armeniaca cv. Priana) and plum (P. domestica cv. Prune d'Ente). To our knowledge, this is the first report of natural infection of CVA in plum. The symptoms observed in the infected plum are reminiscent of those caused by severe Prune dwarf virus (PDV) strains. Infection by PDV was confirmed using a PDV-specific PCR assay. The contribution, if any, of CVA to the symptoms observed remains to be evaluated. These findings suggest that the possible presence of CVA in noncherry Prunus spp. hosts should be taken into consideration by quarantine and certification programs. References: (1) X. Foissac et al. Acta Hortic. 550:3743, 2001. (2) W. Jelkmann. J. Gen. Virol. 76:2015, 1995. (3) M. J. Kirby et al. Plant Pathol. 50:6, 2001.

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