Assessing the Impact on Virus Transmission and Insect Vector Behavior of a Viral Mixed Infection in Melon

Mixed viral infections in plants are common, and can result in synergistic or antagonistic interactions. Except in complex diseases with severe symptoms, mixed infections frequently remain unnoticed, and their impact on insect vector transmission is largely unknown. In this study, we considered mixed infections of two unrelated viruses commonly found in melon plants, the crinivirus cucurbit yellow stunting disorder virus (CYSDV) and the potyvirus watermelon mosaic virus (WMV), and evaluated their vector transmission by whiteflies and aphids, respectively. Their dynamics of accumulation was analyzed until 60 days postinoculation (dpi) in mixed-infected plants, documenting reduced titers of WMV and much higher titers of CYSDV compared with single infections. At 24 dpi, corresponding to the peak of CYSDV accumulation, similar whitefly transmission rates were obtained when comparing either individual or mixed-infected plants as CYSDV sources, although its secondary dissemination was slightly biased toward plants previously infected with WMV, regardless of the source plant. However, at later time points, mixed-infected plants partially recovered from the initially severe symptoms, and CYSDV transmission became significantly higher. Interestingly, aphid transmission rates both at early and late time points were unaltered when WMV was acquired from mixed-infected plants despite its reduced accumulation. This lack of correlation between WMV accumulation and transmission could result from compensatory effects observed in the analysis of the aphid feeding behavior by electrical penetration graphs. Thus, our results showed that mixed-infected plants could provide advantages for both viruses, directly favoring CYSDV dissemination while maintaining WMV transmission.

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Osteopontin ImpactsWest Nile virusPathogenesis and Resistance by Regulating Inflammasome Components and Cell Death in the Central Nervous System at Early Time Points

Mediators of Inflammation ◽

10.1155/2017/7582437 ◽

2017 ◽

Vol 2017 ◽

pp. 1-12 ◽

Cited By ~ 4

Author(s):

Nikki Bortell ◽

Claudia Flynn ◽

Bruno Conti ◽

Howard S. Fox ◽

Maria Cecilia G. Marcondes

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Viral Infections ◽

Early Time ◽

Cns Infection ◽

Critical Threshold ◽

Type I ◽

Time Points ◽

Viral Spread ◽

The Impact

Osteopontin (OPN) is a molecule that is common in central nervous system (CNS) pathologies, which participates in the activation, migration, and survival of inflammatory cells. However, the mechanisms by which OPN modulates inflammatory pathways are not clear. To understand the role of OPN in CNS viral infections, we used a lethal mouse model ofWest Nile virus(WNV), characterized by the injection of high doses of the Eg101 strain of WNV, causing the increase of OPN levels in the brain since early time points. To measure the impact of OPN in neuropathogenesis and resistance, we compared C57BI/6 WT with mice lacking the OPN gene (OPN KO). OPN KO presented a significantly higher mortality compared to WT mice, detectable since day 5 pi. Our data suggests that OPN expression at early time points may provide protection against viral spread in the CNS by negatively controlling the type I IFN-sensitive, caspase 1-dependent inflammasome, while promoting an alternative caspase 8-associated pathway, to control the apoptosis of infected cells during WNV infection in the CNS. Overall, we conclude that the expression of OPN maintains a critical threshold in the innate immune response that controls apoptosis and lethal viral spread in early CNS infection.

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Assessment of the Current Status of Potyviruses in Watermelon and Pumpkin Crops in Spain: Epidemiological Impact of Cultivated Plants and Mixed Infections

Plants ◽

10.3390/plants10010138 ◽

2021 ◽

Vol 10 (1) ◽

pp. 138

Author(s):

Celia De Moya-Ruiz ◽

Pilar Rabadán ◽

Miguel Juárez ◽

Pedro Gómez

Keyword(s):

Viral Load ◽

Mosaic Virus ◽

Plant Species ◽

Viral Infections ◽

Current Status ◽

Cultivated Plants ◽

Watermelon Mosaic Virus ◽

Cdna Clones ◽

Mixed Infections ◽

Cultivated Plant

Viral infections on cucurbit plants cause substantial quality and yield losses on their crops. The diseased plants can often be infected by multiple viruses, and their epidemiology may depend, in addition to the agro-ecological management practices, on the combination of these viral infections. Watermelon mosaic virus (WMV) is one of the most prevalent viruses in cucurbit crops, and Moroccan watermelon mosaic virus (MWMV) emerged as a related species that threatens these crops. The occurrence of WMV and MWMV was monitored in a total of 196 apical-leaf samples of watermelon and pumpkin plants that displayed mosaic symptoms. The samples were collected from 49 fields in three major cucurbit-producing areas in Spain (Castilla La-Mancha, Alicante, and Murcia) for three consecutive (2018–2020) seasons. A molecular hybridization dot-blot method revealed that WMV was mainly (53%) found in both cultivated plants, with an unadvertised occurrence of MWMV. To determine the extent of cultivated plant species and mixed infections on viral dynamics, two infectious cDNA clones were constructed from a WMV isolate (MeWM7), and an MWMV isolate (ZuM10). Based on the full-length genomes, both isolates were grouped phylogenetically with the Emergent and European clades, respectively. Five-cucurbit plant species were infected steadily with either WMV or MWMV cDNA clones, showing variations on symptom expressions. Furthermore, the viral load varied depending on the plant species and infection type. In single infections, the WMV isolate showed a higher viral load than the MWMV isolate in melon and pumpkin, and MWMV only showed higher viral load than the WMV isolate in zucchini plants. However, in mixed infections, the viral load of the WMV isolate was greater than MWMV isolate in melon, watermelon and zucchini, whereas MWMV isolate was markedly reduced in zucchini. These results suggest that the impaired distribution of MWMV in cucurbit crops may be due to the cultivated plant species, in addition to the high prevalence of WMV.

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Measurable Residual Disease Assessed by Flow-Cytometry Is a Stable Prognostic Factor for Pediatric T-Cell Acute Lymphoblastic Leukemia in Consecutive SEHOP Protocols Whereas the Impact of Oncogenetics Depends on Treatment

Frontiers in Pediatrics ◽

10.3389/fped.2020.614521 ◽

2021 ◽

Vol 8 ◽

Author(s):

Nerea Vega-García ◽

Sara Perez-Jaume ◽

Elena Esperanza-Cebollada ◽

Clara Vicente-Garcés ◽

Montserrat Torrebadell ◽

...

Keyword(s):

Flow Cytometry ◽

Acute Lymphoblastic Leukemia ◽

Residual Disease ◽

Lymphoblastic Leukemia ◽

Late Time ◽

Time Points ◽

Cell Acute Lymphoblastic Leukemia ◽

Wbc Count ◽

The Impact ◽

Measurable Residual Disease

Robust and applicable risk-stratifying genetic factors at diagnosis in pediatric T-cell acute lymphoblastic leukemia (T-ALL) are still lacking, and most protocols rely on measurable residual disease (MRD) assessment. In our study, we aimed to analyze the impact of NOTCH1, FBXW7, PTEN, and RAS mutations, the measurable residual disease (MRD) levels assessed by flow cytometry (FCM-MRD) and other reported risk factors in a Spanish cohort of pediatric T-ALL patients. We included 199 patients treated with SEHOP and PETHEMA consecutive protocols from 1998 to 2019. We observed a better outcome of patients included in the newest SEHOP-PETHEMA-2013 protocol compared to the previous SHOP-2005 cohort. FCM-MRD significantly predicted outcome in both protocols, but the impact at early and late time points differed between protocols. The impact of FCM-MRD at late time points was more evident in SEHOP-PETHEMA 2013, whereas in SHOP-2005 FCM-MRD was predictive of outcome at early time points. Genetics impact was different in SHOP-2005 and SEHOP-PETHEMA-2013 cohorts: NOTCH1 mutations impacted on overall survival only in the SEHOP-PETHEMA-2013 cohort, whereas homozygous deletions of CDKN2A/B had a significantly higher CIR in SHOP-2005 patients. We applied the clinical classification combining oncogenetics, WBC count and MRD levels at the end of induction as previously reported by the FRALLE group. Using this score, we identified different subgroups of patients with statistically different outcome in both Spanish cohorts. In SHOP-2005, the FRALLE classifier identified a subgroup of high-risk patients with poorer survival. In the newest protocol SEHOP-PETHEMA-2013, a very low-risk group of patients with excellent outcome and no relapses was detected, with borderline significance. Overall, FCM-MRD, WBC count and oncogenetics may refine the risk-stratification, helping to design tailored approaches for pediatric T-ALL patients.

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When Viruses Play Team Sports: Mixed Infections in Plants

Phytopathology ◽

10.1094/phyto-07-19-0250-fi ◽

2020 ◽

Vol 110 (1) ◽

pp. 29-48 ◽

Cited By ~ 20

Author(s):

Ana Beatriz Moreno ◽

Juan José López-Moya

Keyword(s):

Viral Infections ◽

Team Sports ◽

Plant Viruses ◽

Multiple Infections ◽

Mixed Infections ◽

Transmission Mechanisms ◽

Single Host ◽

Complex Events ◽

Experimental Approaches ◽

The Impact

The pathological importance of mixed viral infections in plants might be underestimated except for a few well-characterized synergistic combinations in certain crops. Considering that the host ranges of many viruses often overlap and that most plant species can be infected by several unrelated viruses, it is not surprising to find more than one virus simultaneously in the same plant. Furthermore, dispersal of the majority of plant viruses relies on efficient transmission mechanisms mediated by vector organisms, mainly but not exclusively insects, which can contribute to the occurrence of multiple infections in the same plant. Recent work using different experimental approaches has shown that mixed viral infections can be remarkably frequent, up to the point that they could be considered the rule more than the exception. The purpose of this review is to describe the impact of multiple infections not only on the participating viruses themselves but also on their vectors and on the common host. From this standpoint, mixed infections arise as complex events that involve several cross-interacting players, and they consequently require a more general perspective than the analysis of single-virus/single-host approaches for a full understanding of their relevance.

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A mathematical model for biodiversity diluting transmission of zika virus through competition mechanics

Discrete and Continuous Dynamical Systems - Series B ◽

10.3934/dcdsb.2021235 ◽

2021 ◽

Vol 0 (0) ◽

pp. 0

Author(s):

Zongmin Yue ◽

Fauzi Mohamed Yusof

Keyword(s):

Infectious Diseases ◽

Zika Virus ◽

Biological Diversity ◽

Viral Infections ◽

Virus Transmission ◽

Dilution Effect ◽

Positive Role ◽

Vector Borne ◽

The Stability ◽

The Impact

<p style='text-indent:20px;'>Whether increasing biodiversity will lead to a promotion (amplification effect) or inhibition (dilution effect) in the transmission of infectious diseases remains to be discovered. In vector-borne infectious diseases, Lyme Disease (LD) and West Nile Virus (WNV) have become typical examples of the dilution effect of biodiversity. Thus, as a vector-borne disease, biodiversity may also play a positive role in the control of the Zika virus. We developed a Zika virus model affected by biodiversity through a competitive mechanism. Through the qualitative analysis of the model, the stability condition of the disease-free equilibrium point and the control threshold of the disease - the basic reproduction number is given. Not only has the numerical analysis verified the inference results, but also it has shown the regulatory effect of the competition mechanism on Zika virus transmission. As competition limits the size of the vector population, the number of final viral infections also decreases. Besides, we also find that under certain parameter conditions, the dilution effect may disappear because of the different initial values. Finally, we emphasized the impact of human activities on biological diversity, to indirectly dilute the abundance of diversity and make the virus continuously spread.</p>

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Impact of Wheat streak mosaic virus and Triticum mosaic virus Coinfection of Wheat on Transmission Rates by Wheat Curl Mites

Plant Disease ◽

10.1094/pdis-08-14-0868-re ◽

2015 ◽

Vol 99 (8) ◽

pp. 1170-1174 ◽

Cited By ~ 8

Author(s):

C. Oliveira-Hofman ◽

S. N. Wegulo ◽

S. Tatineni ◽

G. L. Hein

Keyword(s):

Mosaic Virus ◽

Vector Competence ◽

Virus Transmission ◽

Wheat Streak Mosaic Virus ◽

Transmission Rates ◽

Wheat Curl Mite ◽

Virus Complex ◽

The Impact

Wheat streak mosaic virus (WSMV) and Triticum mosaic virus (TriMV) are transmitted by the wheat curl mite (WCM, Aceria tosichella), and coinfections of wheat by these viruses are common in the field. Previous work has shown that mite genotypes vary in their ability to transmit TriMV. However, the degree to which coinfection of wheat modifies WCM vector competence has not been studied. The objective was to determine whether mite genotypes differed in virus transmission ability when feeding on wheat coinfected by WSMV and TriMV. First, WCM genotype type 2 was used to determine virus transmission rates from mock-, WSMV-, TriMV-, and coinfected wheat plants. Transmission rates were determined by using single-mite transfers from replicated source plants. Coinfection reduced WSMV transmission by type 2 WCM from 50 to 35.6%; however, coinfection increased TriMV transmission from 43.3 to 56.8%. Mite survival on single-mite transfer test plants indicates that the reduction in WSMV transmission may result from poor mite survival when TriMV is present. In a second study, two separate colonies of WCM genotype type 1 were tested to assess the impact of coinfection on transmission. Type 1 mites did not transmit TriMV from coinfected plants but the two colonies varied in transmission rates for WSMV (20.9 to 36.5%). Even though these changes in mite transmission rates are moderate, they help explain the high relative incidence of TriMV-positive plants that are coinfected with WSMV in field observations. These findings begin to demonstrate the complicated interactions found in this mite–virus complex.

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Effects of COVID-19 prevention procedures on other common infections: a systematic review

European Journal of Medical Research ◽

10.1186/s40001-021-00539-1 ◽

2021 ◽

Vol 26 (1) ◽

Author(s):

Omid Dadras ◽

Seyed Ahmad Seyed Alinaghi ◽

Amirali Karimi ◽

Mehrzad MohsseniPour ◽

Alireza Barzegary ◽

...

Keyword(s):

Systematic Review ◽

Infectious Diseases ◽

Viral Infections ◽

Respiratory Infections ◽

Large Population ◽

Virus Transmission ◽

Population Based ◽

World Health ◽

Prevention Measures ◽

The Impact

Abstract Introduction Since the outbreak of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) began, necessary measures to prevent virus transmission and reduce mortality have been implemented, including mandatory public use of masks, regular hand-sanitizing and hand-washing, social distancing, avoidance of crowds, remote work, and cancellation of public events. During and after the introduction of COVID-19 lockout, we performed a systematic review of available published literature to investigate the incidence of seasonal influenza and other respiratory viral infections. Methods PubMed, Embase, Web of Science, Scopus, Science Direct, Google Scholar, Research Gate, and the World Health Organization databases and websites were systematically searched for original studies concerning the impact of COVID-19 prevention means and measures on other common respiratory infectious diseases during the pandemic published by March 2021. Results The findings showed that the adherence to health protocols to prevent COVID-19 could help to reduce the incidence of other infectious diseases such as influenza, pneumonia, and Mycobacterium tuberculosis. Conclusion The implemented prevention measures and protocols might have reduced the incidence of influenza and some other common respiratory infections. However, controversies exist on this matter and future large population-based studies might provide further information to address these controversies.

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Novel Applications of Nanotechnology in Controlling HIV and HSV Infections

Current Drug Research Reviews ◽

10.2174/2589977512999201124121931 ◽

2020 ◽

Vol 12 ◽

Author(s):

Sai Akilesh M ◽

Ashish Wadhwani

Keyword(s):

Drug Delivery ◽

Viral Infections ◽

Polymeric Nanoparticles ◽

Volume Ratio ◽

Fold Increase ◽

Multi Drug Resistance ◽

Health Crisis ◽

Pharmaceutical Properties ◽

Simplex Virus ◽

The Impact

: Infectious diseases have been prevalent since many decades and viral pathogens have caused global health crisis and economic meltdown on a devastating scale. High occurrence of newer viral infections in the recent years, in spite of the progress achieved in the field of pharmaceutical sciences defines the critical need for newer and more effective antiviral therapies and diagnostics. The incidence of multi-drug resistance and adverse effects due to the prolonged use of anti-viral therapy is also a major concern. Nanotechnology offers a cutting edge platform for the development of novel compounds and formulations for biomedical applications. The unique properties of nano-based materials can be attributed to the multi-fold increase in the surface to volume ratio at the nano-scale, tunable surface properties of charge and chemical moieties. Idealistic pharmaceutical properties such as increased bioavailability and retention times, lower toxicity profiles, sustained release formulations, lower dosage forms and most importantly, targeted drug delivery can be achieved through the approach of nanotechnology. The extensively researched nano-based materials are metal and polymeric nanoparticles, dendrimers and micelles, nano-drug delivery vesicles, liposomes and lipid based nanoparticles. In this review article, the impact of nanotechnology on the treatment of Human Immunodeficiency Virus (HIV) and Herpes Simplex Virus (HSV) viral infections during the last decade are outlined.

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Model-based evaluation of school- and non-school-related measures to control the COVID-19 pandemic

Nature Communications ◽

10.1038/s41467-021-21899-6 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Ganna Rozhnova ◽

Christiaan H. van Dorp ◽

Patricia Bruijning-Verhagen ◽

Martin C. J. Bootsma ◽

Janneke H. H. M. van de Wijgert ◽

...

Keyword(s):

Reproduction Number ◽

Additional Benefit ◽

Transmission Model ◽

Time Points ◽

School Based ◽

Admission Data ◽

Age Structured ◽

The Impact ◽

Pandemic Wave

AbstractThe role of school-based contacts in the epidemiology of SARS-CoV-2 is incompletely understood. We use an age-structured transmission model fitted to age-specific seroprevalence and hospital admission data to assess the effects of school-based measures at different time points during the COVID-19 pandemic in the Netherlands. Our analyses suggest that the impact of measures reducing school-based contacts depends on the remaining opportunities to reduce non-school-based contacts. If opportunities to reduce the effective reproduction number (Re) with non-school-based measures are exhausted or undesired and Re is still close to 1, the additional benefit of school-based measures may be considerable, particularly among older school children. As two examples, we demonstrate that keeping schools closed after the summer holidays in 2020, in the absence of other measures, would not have prevented the second pandemic wave in autumn 2020 but closing schools in November 2020 could have reduced Re below 1, with unchanged non-school-based contacts.

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Aphid–Plant–Phytovirus Pathosystems: Influencing Factors from Vector Behaviour to Virus Spread

Agriculture ◽

10.3390/agriculture11060502 ◽

2021 ◽

Vol 11 (6) ◽

pp. 502

Author(s):

Junior Corneille Fingu-Mabola ◽

Frédéric Francis

Keyword(s):

Influencing Factors ◽

Virus Transmission ◽

Physical Factors ◽

Factors Affecting ◽

Vector Borne Diseases ◽

Vector Behaviour ◽

Crop Fields ◽

Host Seeking ◽

The Impact ◽

Vector Efficiency

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.

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