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1.
High Alt Med Biol ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634740

RESUMO

Grimm, Mirjam, Lucie Ziegler, Annina Seglias, Maamed Mademilov, Kamila Magdieva, Gulzada Mirzalieva, Aijan Taalaibekova, Simone Suter, Simon R. Schneider, Fiona Zoller, Vera Bissig, Lukas Reinhard, Meret Bauer, Julian Müller, Tanja L. Ulrich, Arcangelo F. Carta, Patrick R. Bader, Konstantinos Bitos, Aurelia E. Reiser, Benoit Champigneulle, Damira Ashyralieva, Philipp M. Scheiwiller, Silvia Ulrich, Talant M. Sooronbaev, Michael Furian, and Konrad E. Bloch. SARS-CoV-2 Transmission during High-Altitude Field Studies. High Alt Med Biol. 00:00-00, 2024. Background: Throughout the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) pandemic, virus transmission during clinical research was of concern. Therefore, during high-altitude field studies performed in 2021, we took specific COVID-19 precautions and investigated the occurrence of SARS-CoV-2 infection. Methods: From May to September 2021, we performed studies in patients with chronic obstructive pulmonary disease (COPD) and in healthy school-age children in Kyrgyzstan in high-altitude facilities at 3,100 m and 3,250 m and at 760 m. The various implemented COVID-19 safety measures included systematic SARS-CoV-2 rapid antigen testing (RAT). Main outcomes were SARS-CoV-2-RAT-positive rate among participants and staff at initial presentation (prevalence) and SARS-CoV-2-RAT-positive conversion during and within 10 days after studies (incidence). Results: Among 338 participants and staff, SARS-CoV-2-RAT-positive prevalence was 15 (4.4%). During mean ± SD duration of individual study participation of 3.1 ± 1.0 day and within 10 days, RAT-positive conversion occurred in 1/237(0.4%) participants. Among staff working in studies for 31.5 ± 29.3 days, SARS-CoV-2-RAT-positive conversion was 11/101(10.9%). In all 338 individuals involved in the studies over the course of 15.6 weeks, the median SARS-CoV-2-RAT-positive incidence was 0.00%/week (quartiles 0.00; 0.64). Over the same period, the median background incidence among the total Kyrgyz population of 6,636 million was 0.06%/week (0.03; 0.11), p = 0.013 (Wilcoxon rank sum test). Conclusions: Taking precautions by implementing specific safety measures, SARS-CoV-2 transmission during clinical studies was very rare, and the SARS-CoV-2 incidence among participants and staff was lower than that in the general population during the same period. The results are reassuring and may help in decision-making on the conduct of clinical research in similar settings.

2.
Front Vet Sci ; 11: 1330657, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628945

RESUMO

Lumpy skin disease (LSD) is a transboundary viral infection, affecting cattle with characteristic manifestations involving multiple body systems. A distinctive characteristic of lumpy skin disease is the subclinical disease manifestation wherein animals have viremia and shed the virus through nasal and ocular discharges, while exhibiting no nodules but enlarged lymph nodes that are easily oversighted by inexperienced vets. Further research on the role of subclinically ill animals in the transmission of LSD virus (LSDV) can contribute to the development of more effective tools to control the disease worldwide. Thus, this study aims to determine the potential role of subclinical infection in virus transmission in a non-vector-borne manner. To achieve this, we inoculated animals with the recombinant vaccine-like strain (RVLS) Udmurtiya/2019 to cause clinical and subclinical LSDV infection. After the disease manifestation, we relocated the subclinically ill animals to a new clean facility followed by the introduction of another five animals to determine the role of RVLS-induced subclinical infection in the virus transmission via direct/indirect contact. After the introduction of the naïve animals to the relocated subclinically ill ones in a shared airspace, two introduced animals contracted the virus (clinically and subclinically), showing symptoms of fever, viremia, and seroconversion in one animal, while three other introduced animals remained healthy and PCR-negative until the end of the study. In general, the findings of this study suggest the importance of considering LSDV subclinical infection as a high-risk condition in disease management and outbreak investigations.

3.
Pest Manag Sci ; 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38459962

RESUMO

BACKGROUND: The Southern rice black-streaked dwarf virus (SRBSDV) transmitted by Sogatella furcifera constitutes a threat to sustainable rice production. However, most rice varieties are highly vulnerable to SRBSDV, whereas the occurrence of the viral disease varies significantly under field conditions. This study aimed to evaluate the potential of rice varietal resistance to S. furcifera in reducing SRBSDV transmission. RESULTS: Among the five rice varieties, Zhongzheyou8 and Deyou108 exhibited high resistance to S. furcifera, Baixiangnuo33 was susceptible, and TN1 and Diantun502 were highly susceptible. The S. furcifera generally showed non-preference for and low feeding on the Zhongzheyou8 and Deyou108 plants, which may explain the resistance of these varieties to S. furcifera. Transmission of SRBSDV by S. furcifera was significantly impaired on the resistant varieties, both inoculation and acquisition rates were much lower on Zhongzheyou8 than on TN1. The short durations of S. furcifera salivation and phloem-related activities and the low S. furcifera feeding amount may explain the reduced SRBSDV inoculation and acquisition rates associated with Zhongzheyou8. Spearman's rank correlation revealed a significant negative correlation between S. furcifera resistance and SRBSDV transmission among the tested varieties. CONCLUSION: The results indicate that rice varietal resistance to the vector S. furcifera hinders SRBSDV transmission, which is largely associated with the host plant selection and feeding behaviors of the vector. The current findings shed light on the management of the SRBSDV viral disease through incorporation of S. furcifera resistant rice varieties in the management protocol. © 2024 Society of Chemical Industry.

4.
BMC Genomics ; 25(1): 311, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532315

RESUMO

BACKGROUND: The Argentine stem weevil (ASW, Listronotus bonariensis) is a significant pasture pest in Aotearoa New Zealand, primarily controlled by the parasitoid biocontrol agent Microctonus hyperodae. Despite providing effective control of ASW soon after release, M. hyperodae parasitism rates have since declined significantly, with ASW hypothesised to have evolved resistance to its biocontrol agent. While the parasitism arsenal of M. hyperodae has previously been investigated, revealing many venom components and an exogenous novel DNA virus Microctonus hyperodae filamentous virus (MhFV), the effects of said arsenal on gene expression in ASW during parasitism have not been examined. In this study, we performed a multi-species transcriptomic analysis to investigate the biology of ASW parasitism by M. hyperodae, as well as the decline in efficacy of this biocontrol system. RESULTS: The transcriptomic response of ASW to parasitism by M. hyperodae involves modulation of the weevil's innate immune system, flight muscle components, and lipid and glucose metabolism. The multispecies approach also revealed continued expression of venom components in parasitised ASW, as well as the transmission of MhFV to weevils during parasitism and some interrupted parasitism attempts. Transcriptomics did not detect a clear indication of parasitoid avoidance or other mechanisms to explain biocontrol decline. CONCLUSIONS: This study has expanded our understanding of interactions between M. hyperodae and ASW in a biocontrol system of critical importance to Aotearoa-New Zealand's agricultural economy. Transmission of MhFV to ASW during successful and interrupted parasitism attempts may link to a premature mortality phenomenon in ASW, hypothesised to be a result of a toxin-antitoxin system. Further research into MhFV and its potential role in ASW premature mortality is required to explore whether manipulation of this viral infection has the potential to increase biocontrol efficacy in future.


Assuntos
Himenópteros , Vespas , Gorgulhos , Animais , Controle Biológico de Vetores , Insetos/genética , Himenópteros/genética , Gorgulhos/genética , Perfilação da Expressão Gênica , Vespas/genética , Interações Hospedeiro-Parasita
5.
J Gen Virol ; 105(3)2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38441560

RESUMO

Plant viruses are transmitted mechanically or by vegetative propagation, and by vectors such as arthropods, fungi, nematodes, or parasitic plants. Sources to access available information regarding plant virus transmissions are scattered and require extensive literature searches. Here, a recently created plant virus transmission database is described. This was developed to provide access to the modes of transmission and vectors of over 1600 plant viruses. The database was compiled using over 3500 publication records spanning the last 100 years. The information is publicly accessible via https://library.wur.nl/WebQuery/virus and fully searchable by virus name, taxonomic position, mode of transmission or vector.


Assuntos
Artrópodes , Vírus de Plantas , Animais , Vírus de Plantas/genética , Bases de Dados Factuais
6.
J Aerosol Med Pulm Drug Deliv ; 37(2): 51-63, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38285475

RESUMO

Background: Quantitatively collecting and characterizing exhaled aerosols is vital for infection risk assessment, but the entire droplet size spectrum has often been neglected. We analyzed particle number and size distribution of healthy participants in various respiratory activities, considering inter-individual variability, and deployed a simplified far-field model to inform on infection risks. Methods: Participants repeated the same respiratory activities on two visits. Particles were collected using an airtight extraction helmet supplied with High Efficiency Particulate Air (HEPA) filtered air. The sampling volume flow was transported to two particle counters covering the small and large particle spectrum. The applied simple mass balance model included respiratory activity, viral load, room size, and air exchange rates. Results: Thirty participants completed the study. The major fraction of the number-based size distribution was <5 µm in all respiratory activities. In contrast, the major fraction of the volume-based size distribution was 2-12 µm in tidal breathing, but >60 µm in all other activities. Aerosol volume flow was lowest in tidal breathing, 10-fold higher in quiet/normal speaking, deep breathing, coughing, and 100-fold higher in loud speaking/singing. Intra-individual reproducibility was high. Between participants, aerosol volume flow varied by two orders of magnitude in droplets <80 µm, and three orders of magnitude in droplets >80 µm. Simple model calculations not accounting for potential particle size-dependent differences in viral load and infection-related differences were used to model airborne pathogen concentrations. Conclusions: Quantitative analysis of exhaled aerosols for the entire droplet size spectrum as well as the variability in aerosol emission between individuals provides information that can support infection research. Clinical Trial Registration number: NCT04771585.


Assuntos
Aerossóis e Gotículas Respiratórios , Humanos , Reprodutibilidade dos Testes , Tamanho da Partícula , Administração por Inalação , Aerossóis
7.
J Hosp Infect ; 144: 75-84, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38040038

RESUMO

BACKGROUND: The contagiousness of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is known to be linked to the emission of bioaerosols. Thus, aerosol-generating procedures (AGPs) could increase the risk of infection among healthcare workers (HCWs). AIM: To investigate the impact of an aerosol protection box, the SplashGuard Caregiver (SGGC) with suction system, by direct analysis of the presence of viral particles after an AGP, and by using the computational fluid dynamics (CFD) simulation method. METHODS: This prospective observational study investigated HCWs caring for patients with SARS-CoV-2 admitted to an intensive care unit (ICU). Rooms were categorized as: SGCG present and SGCG absent. Virus detection was performed through direct analysis, and using a CFD model to simulate the movement dynamics of airborne particles produced by a patient's respiratory activities. FINDINGS: Of the 67 analyses performed, three samples tested positive on quantitative polymerase chain reaction: one of 33 analyses in the SCCG group (3%) and two of 34 analyses in the non-SGCG group (5.9%). CFD simulations showed that: (1) reduction of the gaps of an SGCG could decrease the number of emitted particles remaining airborne within the room by up to 70%; and (2) positioning HCWs facing the opposite direction to the main air flow would reduce their exposure. CONCLUSIONS: This study documented the presence of SARS-CoV-2 among HCWs in a negative pressure ICU room of an infected patient with or without the use of an SGCG. The simulation will help to improve the design of the SGCG and the positioning of HCWs in the room.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , Cuidadores , Estudos Prospectivos , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Aerossóis e Gotículas Respiratórios , Unidades de Terapia Intensiva
8.
Econ Hum Biol ; 52: 101314, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38056317

RESUMO

Outbreaks of COVID-19 in crowded work locations led to mass infection events during the pandemic that stressed health capacity in rural communities. This led to disparate responses - either isolating and restricting workers to facilities and potentially amplifying spread between them, more intense community wide restrictions, or an acceptance of higher disease spread. An extreme case is the salmon fishery in Bristol Bay, Alaska, where fishermen, factory workers, and residents all interact during the summer fishing season. During the pandemic, policy measures were debated, including community mask mandates, restricting workers to their boats and factories, and even closing the valuable seasonal fishery. We develop an agent-based SIR model (ABM) to examine COVID-19 transmission in a resource-dependent community populated by distinct subgroups. The model includes a virus spreading within and between three heterogenous populations who interact with other members of their type in their home location, and with different types of agents when out in the community. We simulate various non-pharmaceutical interventions and vaccination rates across these groups. Results demonstrate the efficacy of non-pharmaceutical interventions and vaccinations, as well as tradeoffs between duration and intensity and tradeoffs between groups impacted by the outbreak. This ABM demonstrates the impact of public policy mechanisms on health outcomes in resource-dependent communities with distinct populations.


Assuntos
COVID-19 , Humanos , Pandemias , Surtos de Doenças , Vacinação , Local de Trabalho
9.
Adv Mater ; 36(9): e2305378, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37931029

RESUMO

The recent prevalence of monkeypox has led to the declaration of a Public Health Emergency of International Concern. Monkeypox lesions are typically ulcers or pustules (containing high titers of replication-competent virus) in the skin and mucous membranes, which allow monkeypox virus to transmit predominantly through intimate contact. Currently, effective clinical treatments for monkeypox are lacking, and strategies for blocking virus transmission are fraught with drawbacks. Herein, this work constructs a biomimetic nanotemplate (termed TBD@M NPs) with macrophage membranes as the coat and polymeric nanoparticles loading a versatile aggregation-induced emission featured photothermal molecule TPE-BT-DPTQ as the core. In a surrogate mouse model of monkeypox (vaccinia-virus-infected tail scarification model), intravenously injected TBD@M NPs show precise tracking and near-infrared region II fluorescence imaging of the lesions. Upon 808 nm laser irradiation, the virus is eliminated by the photothermal effect and the infected wound heals rapidly. More importantly, the inoculation of treated lesion tissue suspensions does not trigger tail infection or inflammatory activation in healthy mice, indicating successful blockage of virus transmission. This study demonstrates for the first time monkeypox theranostics using nanomedicine, and may bring a new insight into the development of a viable strategy for monkeypox management in clinical trials.


Assuntos
Nanopartículas , Animais , Camundongos , Terapia Fototérmica , Biomimética , Macrófagos , Nanopartículas/uso terapêutico
10.
Insect Sci ; 31(1): 255-270, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37358052

RESUMO

Sap-sucking insects often transmit plant viruses but also carry insect viruses, which infect insects but not plants. The impact of such insect viruses on insect host biology and ecology is largely unknown. Here, we identified a novel insect-specific virus carried by brown citrus aphid (Aphis citricidus), which we tentatively named Aphis citricidus picornavirus (AcPV). Phylogenetic analysis discovered a monophyletic cluster with AcPV and other unassigned viruses, suggesting that these viruses represent a new family in order Picornavirales. Systemic infection with AcPV triggered aphid antiviral immunity mediated by RNA interference, resulting in asymptomatic tolerance. Importantly, we found that AcPV was transmitted horizontally by secretion of the salivary gland into the feeding sites of plants. AcPV influenced aphid stylet behavior during feeding and increased the time required for intercellular penetration, thus promoting its transmission among aphids with plants as an intermediate site. The gene expression results suggested that this mechanism was linked with transcription of salivary protein genes and plant defense hormone signaling. Together, our results show that the horizontal transmission of AcPV in brown citrus aphids evolved in a manner similar to that of the circulative transmission of plant viruses by insect vectors, thus providing a new ecological perspective on the activity of insect-specific viruses found in aphids and improving the understanding of insect virus ecology.


Assuntos
Afídeos , Citrus , Vírus de Insetos , Vírus de Plantas , Vírus de RNA , Animais , Afídeos/genética , RNA/metabolismo , Vírus de Insetos/genética , Filogenia , Vírus de RNA/genética , Vírus de Plantas/genética , Doenças das Plantas
11.
Braz. j. biol ; 84: e246460, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1350310

RESUMO

Abstract Field survey study was conducted season (2017). Soybeans and weeds were weekly sampled randomly. Thrips adults were identified and counted. Detection of the virus isolate and the natural incidence was determined using; Mechanical transmission, host range, DAS-ELISA, RT-PCR. The natural incidence thrips individuals was detected depending on the SVNV% in thrips individuals and weeds hosts. Ten thrips species were associated with soybean plants in the field. The most abundant species was T. tabaci, average 256.5 average no.of individuals, followed by F. occidentalis (142.5 average no. of individuals), then N. variabilis (86.6/ average no. of individuals). Fourteen thrips species occurred on 5 legumes field crops and 41 weed plant species within soybean field. The highest average number 40.6.of individuals were recorded on Ammi majus. While the lowest one 3.3 average no. of individuals were on Urtica urens. Only 21diagnostic plant species were susceptible to infection with SVNV. G. max and Vigna radiate, were the highest percentage of infection 80% followed by V. unguilata & N. benthamiana, 75%. Egyptian isolate of Soybean vein necrosis virus (SVNV) in this study showed a high degree of similarity and it is closely related to TSWV from Egypt (DQ479968) and TCSV from USA (KY820965) with nucleotide sequence identity of 78%. Four thrips species transmitted SVNV (F. fusca 4.0%, F. schultzei 4.3%, F. tritici 3.3% and N. variabilis 68.0% transmission). Both C. phaseoli and M. sjostedti can acquire the virus but unable to transmit it. The following species; T. tabaci, F. occidentalis, S. dorsallis and T. palmi cannot acquire or transmit SVNV. The incidence of SVNV in the field started by the end of July then increased gradualy from 12.7 to 71.3% by the end of the season. In conclusion, few thrips individuals invaded soybean crops are enough to transmit high rate of SVNV within the crop. Furthermore, several vector species are also abundant on weeds, which are the major sources of soybean viruses transmitted to the crops. This information might be important for control and reduce the incidence of SVNV infection.


Resumo O estudo de pesquisa de campo foi realizado na temporada (2017). A soja e as ervas daninhas foram amostradas semanalmente de forma aleatória. Tripes adultos foram identificados e contados. A detecção do vírus isolado e a incidência natural foram determinadas usando transmissão mecânica, gama de hospedeiros, DAS-ELISA, RT-PCR. A incidência natural de tripes em indivíduos foi detectada dependendo da % de SVNV em tripes e hospedeiros infestantes. Dez espécies de tripes foram associadas a plantas de soja no campo. A espécie mais abundante foi T. tabaci, com média de 256,5 número médio de indivíduos, seguida por F. occidentalis (142,5) e N. variabilis (86,6 / número médio de indivíduos). Catorze espécies de tripes ocorreram em 5 culturas de leguminosas e 41 espécies de plantas daninhas dentro de campos de soja. O maior número médio de 40,6 indivíduos foi registrado em Ammi majus. Enquanto o mais baixo, 3,3 número médio de indivíduos, foi no Urtica urens. Apenas 21 espécies de plantas diagnosticadas foram suscetíveis à infecção com SVNV. G. max e Vigna radiate foram os maiores percentuais de infecção, 80%, seguidos por V. unguilata e N. benthamiana, 75%. O isolado egípcio neste estudo mostrou um alto grau de similaridade e está intimamente relacionado ao TSWV do Egito (DQ479968) e ao TCSV dos EUA (KY820965), com identidade de sequência de nucleotídeos de 78%. Quatro espécies de tripes transmitiram SVNV (F. fusca 4,0%, F. schultzei 4,3%, F. tritici 3,3% e N. variabilis 68,0% de transmissão). Tanto C. phaseoli quanto M. sjostedti podem adquirir o vírus, mas não podem transmiti-lo. As seguintes espécies, T. tabaci, F. occidentalis, S. dorsallis e T. palmi não podem adquirir ou transmitir SVNV. A incidência de SVNV no campo, iniciada no final de julho, aumentou gradativamente de 12,7 para 71,3% no final da temporada. Em conclusão, poucos indivíduos de tripes invadiram a cultura da soja e são suficientes para transmitir alta taxa de SVNV dentro da cultura. Além disso, várias espécies de vetores também abundam em ervas daninhas, que são as principais fontes dos vírus da soja transmitidos às lavouras. Essas informações podem ser importantes para controlar e reduzir a incidência de infecção por SVNV.


Assuntos
Humanos , Tospovirus , Doenças das Plantas , Soja , Incidência , Urticaceae , Egito/epidemiologia , Plantas Daninhas , Necrose
12.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469268

RESUMO

Abstract Field survey study was conducted season (2017). Soybeans and weeds were weekly sampled randomly. Thrips adults were identified and counted. Detection of the virus isolate and the natural incidence was determined using; Mechanical transmission, host range, DAS-ELISA, RT-PCR. The natural incidence thrips individuals was detected depending on the SVNV% in thrips individuals and weeds hosts. Ten thrips species were associated with soybean plants in the field. The most abundant species was T. tabaci, average 256.5 average no.of individuals, followed by F. occidentalis (142.5 average no. of individuals), then N. variabilis (86.6/ average no. of individuals). Fourteen thrips species occurred on 5 legumes field crops and 41 weed plant species within soybean field. The highest average number 40.6.of individuals were recorded on Ammi majus. While the lowest one 3.3 average no. of individuals were on Urtica urens. Only 21diagnostic plant species were susceptible to infection with SVNV. G. max and Vigna radiate, were the highest percentage of infection 80% followed by V. unguilata & N. benthamiana, 75%. Egyptian isolate of Soybean vein necrosis virus (SVNV) in this study showed a high degree of similarity and it is closely related to TSWV from Egypt (DQ479968) and TCSV from USA (KY820965) with nucleotide sequence identity of 78%. Four thrips species transmitted SVNV (F. fusca 4.0%, F. schultzei 4.3%, F. tritici 3.3% and N. variabilis 68.0% transmission). Both C. phaseoli and M. sjostedti can acquire the virus but unable to transmit it. The following species; T. tabaci, F. occidentalis, S. dorsallis and T. palmi cannot acquire or transmit SVNV. The incidence of SVNV in the field started by the end of July then increased gradualy from 12.7 to 71.3% by the end of the season. In conclusion, few thrips individuals invaded soybean crops are enough to transmit high rate of SVNV within the crop. Furthermore, several vector species are also abundant on weeds, which are the major sources of soybean viruses transmitted to the crops. This information might be important for control and reduce the incidence of SVNV infection.


Resumo O estudo de pesquisa de campo foi realizado na temporada (2017). A soja e as ervas daninhas foram amostradas semanalmente de forma aleatória. Tripes adultos foram identificados e contados. A detecção do vírus isolado e a incidência natural foram determinadas usando transmissão mecânica, gama de hospedeiros, DAS-ELISA, RT-PCR. A incidência natural de tripes em indivíduos foi detectada dependendo da % de SVNV em tripes e hospedeiros infestantes. Dez espécies de tripes foram associadas a plantas de soja no campo. A espécie mais abundante foi T. tabaci, com média de 256,5 número médio de indivíduos, seguida por F. occidentalis (142,5) e N. variabilis (86,6 / número médio de indivíduos). Catorze espécies de tripes ocorreram em 5 culturas de leguminosas e 41 espécies de plantas daninhas dentro de campos de soja. O maior número médio de 40,6 indivíduos foi registrado em Ammi majus. Enquanto o mais baixo, 3,3 número médio de indivíduos, foi no Urtica urens. Apenas 21 espécies de plantas diagnosticadas foram suscetíveis à infecção com SVNV. G. max e Vigna radiate foram os maiores percentuais de infecção, 80%, seguidos por V. unguilata e N. benthamiana, 75%. O isolado egípcio neste estudo mostrou um alto grau de similaridade e está intimamente relacionado ao TSWV do Egito (DQ479968) e ao TCSV dos EUA (KY820965), com identidade de sequência de nucleotídeos de 78%. Quatro espécies de tripes transmitiram SVNV (F. fusca 4,0%, F. schultzei 4,3%, F. tritici 3,3% e N. variabilis 68,0% de transmissão). Tanto C. phaseoli quanto M. sjostedti podem adquirir o vírus, mas não podem transmiti-lo. As seguintes espécies, T. tabaci, F. occidentalis, S. dorsallis e T. palmi não podem adquirir ou transmitir SVNV. A incidência de SVNV no campo, iniciada no final de julho, aumentou gradativamente de 12,7 para 71,3% no final da temporada. Em conclusão, poucos indivíduos de tripes invadiram a cultura da soja e são suficientes para transmitir alta taxa de SVNV dentro da cultura. Além disso, várias espécies de vetores também abundam em ervas daninhas, que são as principais fontes dos vírus da soja transmitidos às lavouras. Essas informações podem ser importantes para controlar e reduzir a incidência de infecção por SVNV.

13.
Cureus ; 15(12): e50171, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38077688

RESUMO

Background Monkeypox is a globally spreading disease, representing a significant threat to human life in all countries of the world, and Saudi Arabia is no exception. This study aimed to assess the knowledge of the general adult population in Riyadh, Saudi Arabia about monkeypox. Methodology This cross-sectional study was conducted in Riyadh, Saudi Arabia among a sample of adults (aged over 18 years) who attended the outpatient clinics of the First Cluster primary healthcare centers, King Saud Medical City, and Ministry of Health in November 2022. A self-administered Arabic questionnaire, including sociodemographic characteristics of the participants, beliefs regarding monkeypox, and knowledge assessment about monkeypox through 23 multiple-choice questions, was utilized. Results The study included 375 participants, of whom 270 (72%) were aged between 26 and 45 years, and 195 (52%) were males. Overall, 258 (68.8%) participants had insufficient knowledge about monkeypox. Multivariate logistic regression analysis revealed that participants aged over 45 years were almost at a three-fold risk of having an insufficient level of knowledge about the disease compared to those aged between 18 and 25 years (adjusted odds ratio (AOR) = 3.03, 95% confidence interval (CI) = 1.07-8.69, p = 0.037). University/higher educated participants were at 61% lower risk of having an insufficient level of knowledge about the disease compared to those with an education level of below secondary school (AOR = 0.39, 95% CI = 0.09-0.65, p = 0.013). Compared to housewives/non-working participants, governmental employees were at a significantly lower risk of having insufficient knowledge about monkeypox (AOR = 0.48, 95% CI = 0.26-0.89, p = 0.020). Conclusions Knowledge of the general population in Riyadh, Saudi Arabia regarding monkeypox is insufficient, particularly regarding the fact that a monkeypox vaccine is available in Saudi Arabia and monkeypox is not a new infection that appeared in 2022. Therefore, there is a need to implement educational sessions at primary care centers and outpatient clinics of hospitals about the disease.

14.
Plants (Basel) ; 12(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37960034

RESUMO

The transmission of plant viruses from infected to healthy host plants is a process in which insects play a major role, using various transmission strategies. Environmental factors have an impact on the transmission of viruses and the subsequent development of infections or diseases. When viruses are successful, plant virus diseases can reach epidemic proportions. Many plants across different regions are vulnerable to viral infections transmitted by the whitefly vector. Begomoviruses, which are transmitted by whiteflies, represent a significant threat to agriculture worldwide. The review highlights the mechanisms of virus acquisition and transmission by whiteflies and explores the factors influencing these interactions. Understanding the impacts of these changes is crucial for managing the spread of pests and mitigating damage to crops. It underscores the need for continued research to elucidate the mechanisms driving plant-insect-virus interactions and to identify new approaches for sustainable pest management.

15.
Plant Dis ; 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37923977

RESUMO

Maize yellow mosaic virus (MaYMV) is an emerging polerovirus that has been detected in maize, other cereal crops and weedy grass species in Asia, Africa, and the Americas. Disease symptoms in maize include prominent leaf tip reddening and stunting. Infection by MaYMV has been reported to reduce plant growth and yields by 10-30% in some instances. In this study, an experimental host range for MaYMV among agronomically important cereal crops and common grasses was established. Additional aphid species were assessed as potential vectors for MaYMV and their transmission efficiencies were determined. Here we report oats, foxtail millet, barley, and rye as new experimental cereal crop hosts of MaYMV in addition to confirming the previously reported hosts of corn, sorghum, wheat, and broom millet. Four of the nine other grass species evaluated were also identified as suitable experimental hosts for MaYMV: ryegrass, switchgrass, green foxtail, and sand love grass. Interestingly, no visible symptoms were present in any of the infected hosts besides the susceptible maize control. Vector range studies identified the greenbug aphid, Schizaphis graminum, as a new vector of MaYMV, though transmission efficiency was lower than the previously reported Rhopalosiphum maidis vector and similar to the other known aphid vector, R. padi. Given MaYMV's global ubiquity, ability to evade detection, and broad host range, further characterization of yield impacts and identification of viable control strategies are desirable.

16.
J Integr Plant Biol ; 2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37924266

RESUMO

Plant viruses are a group of intracellular pathogens that persistently threaten global food security. Significant advances in plant virology have been achieved by Chinese scientists over the last 20 years, including basic research and technologies for preventing and controlling plant viral diseases. Here, we review these milestones and advances, including the identification of new crop-infecting viruses, dissection of pathogenic mechanisms of multiple viruses, examination of multilayered interactions among viruses, their host plants, and virus-transmitting arthropod vectors, and in-depth interrogation of plant-encoded resistance and susceptibility determinants. Notably, various plant virus-based vectors have also been successfully developed for gene function studies and target gene expression in plants. We also recommend future plant virology studies in China.

17.
J Virol ; 97(11): e0106723, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37855618

RESUMO

IMPORTANCE: Many plant viruses are transmitted by insect vectors in a circulative manner. For efficient transmission, the entry of the virus from vector hemolymph into the primary salivary gland (PSG) is a step of paramount importance. Yet, vector components mediating virus entry into PSG remain barely characterized. Here, we demonstrate the role of clathrin-mediated endocytosis and early endosomes in begomovirus entry into whitefly PSG. Our findings unravel the key components involved in begomovirus transport within the whitefly body and transmission by their whitefly vectors and provide novel clues for blocking begomovirus transmission.


Assuntos
Begomovirus , Endocitose , Hemípteros , Animais , Begomovirus/fisiologia , Clatrina/metabolismo , Endossomos , Hemípteros/metabolismo , Hemípteros/virologia , Doenças das Plantas , Glândulas Salivares/metabolismo , Glândulas Salivares/virologia
18.
Pathogens ; 12(10)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37887755

RESUMO

This study aimed to characterize the mRNA signature of milk small extracellular vesicles (sEVs) from BLV-infected cattle. A total of 23 mRNAs, which showed greater abundance in milk sEVs from BLV-infected cattle compared to those from BLV-uninfected (control) cattle, were identified through microarray analyses conducted in our previous study. To assess the significance of these differences in mRNA abundance, milk was collected from six control cattle and twenty-six cattle infected with BLV. The infected cattle were categorized into two distinct groups based on their proviral loads: a group of eight cattle with low proviral loads (LPVL), characterized by <10,000 copies per 105 white blood cells (WBC), and a group of eighteen cattle with high proviral loads (HPVL), marked by ≥10,000 copies per 105 WBC. The qPCR analysis quantified 7 out of 23 mRNAs, including BoLA, CALB1, IL33, ITGB2, MYOF, TGFBR1, and TMEM156, in the milk sEVs from control cattle, LPVL cattle, and HPVL cattle. Significantly, the average relative expression of CALB1 mRNA in milk sEVs was higher in LPVL cattle compared to HPVL cattle and control cattle (p < 0.05), while it was relatively lower in HPVL cattle compared to LPVL cattle and control cattle (p > 0.05). Likewise, the average relative expression of TMEM156 mRNA in milk sEVs was significantly higher in LPVL cattle compared to HPVL cattle (p < 0.05), and relatively lower in HPVL cattle compared to LPVL cattle and control cattle (p > 0.05). The results indicate distinct patterns of CALB1 and TMEM156 mRNA levels in milk sEVs, with higher levels observed in LPVL cattle and lower levels in HPVL cattle. The current study could provide essential information to comprehend the complexities during the progression of BLV infection and direct the exploration of mRNA biomarkers for monitoring the clinical stage of BLV infection.

19.
Int J Mol Sci ; 24(19)2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37834280

RESUMO

Potato virus Y, an important viral pathogen of potato, has several genetic variants and geographic distributions which could be affected by environmental factors, aphid vectors, and reservoir plants. PVY is transmitted to virus-free potato plants by aphids and passed on to the next vegetative generations through tubers, but the effects of tuber transmission in PVY is largely unknown. By using high-throughput sequencing, we investigated PVY populations transmitted to potato plants by aphids in different climate zones of Russia, namely the Moscow and Astrakhan regions. We analyzed sprouts from the tubers produced by field-infected plants to investigate the impact of tuber transmission on PVY genetics. We found a significantly higher diversity of PVY isolates in the Astrakhan region, where winters are shorter and milder and summers are warmer compared to the Moscow region. While five PVY types, NTNa, NTNb, N:O, N-Wi, and SYR-I, were present in both regions, SYRI-II, SYRI-III, and 261-4 were only found in the Astrakhan region. All these recombinants were composed of the genome sections derived from PVY types O and N, but no full-length sequences of such types were present. The composition of the PVY variants in the tuber sprouts was not always the same as in their parental plants, suggesting that tuber transmission impacts PVY genetics.


Assuntos
Afídeos , Potyvirus , Solanum tuberosum , Animais , Potyvirus/genética , Doenças das Plantas , Solanum tuberosum/genética , Federação Russa , Genoma Viral , Afídeos/genética
20.
Animals (Basel) ; 13(19)2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37835686

RESUMO

This study reports on the molecular epidemiology of Ingelvac-PRRS-MLV-associated cases in Hungary for the period 2020-2021. Field epidemiology investigations led the experts to conclude that imported pigs, which were shipped through transit stations in Denmark, introduced the vaccine virus. The movement of fatteners and the neglect of disease control measures contributed to the spread of the virus to PRRS-free pig holdings in the vicinity. Deep sequencing was performed to genetically characterize the genes coding for the virion antigens (i.e., ORF2 through ORF7). The study isolates exhibited a range of 0.1 to 1.8% nucleotide sequence divergence from the Ingelvac PRRS MLV and identified numerous polymorphic sites (up to 57 sites) along the amplified 3.2 kilo base pair genomic region. Our findings confirm that some PRRSV-2 vaccine strains can accumulate very high number of point mutations within a short period in immunologically naive pig herds.

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