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The production of aquatic animals has more than doubled over the last 50 years and is anticipated to continually increase. While fish are recognized as a valuable and sustainable source of nutrition, particularly in the context of human population growth and climate change, the rapid expansion of aquaculture coincides with the emergence of highly pathogenic viruses that often spread globally through aquacultural practices. Here, we provide an overview of the fish virome and its relevance for disease emergence, with a focus on the insights gained through metagenomic sequencing, noting potential areas for future study. In particular, we describe the diversity and evolution of fish viruses, for which the majority have no known disease associations, and demonstrate how viruses emerge in fish populations, most notably at an expanding domestic-wild interface. We also show how wild fish are a powerful and tractable model system to study virus ecology and evolution more broadly and can be used to identify the major factors that shape vertebrate viromes. Central to this is a process of virus-host co-divergence that proceeds over many millions of years, combined with ongoing cross-species virus transmission.
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Evolução Molecular , Doenças dos Peixes , Peixes , Vírus , Animais , Aquicultura/tendências , Doenças dos Peixes/transmissão , Doenças dos Peixes/virologia , Peixes/classificação , Peixes/virologia , Variação Genética , Metagenômica , Filogenia , Viroma/genética , Viroses/transmissão , Viroses/veterinária , Viroses/virologia , Vírus/genética , Vírus/classificaçãoRESUMO
Despite the importance of virulence in epidemiological theory, the relative contributions of host and parasite to virulence outcomes remain poorly understood. Here, we use reciprocal cross experiments to disentangle the influence of host and parasite on core virulence components-infection and pathology-and understand dramatic differences in parasite-induced malformations in California amphibians. Surveys across 319 populations revealed that amphibians' malformation risk was 2.7× greater in low-elevation ponds, even while controlling for trematode infection load. Factorial experiments revealed that parasites from low-elevation sites induced higher per-parasite pathology (reduced host survival and growth), whereas there were no effects of host source on resistance or tolerance. Parasite populations also exhibited marked differences in within-host distribution: ~90% of low-elevation cysts aggregated around the hind limbs, relative to <60% from high-elevation. This offers a novel, mechanistic basis for regional variation in parasite-induced malformations while promoting a framework for partitioning host and parasite contributions to virulence.
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Parasitos , Trematódeos , Infecções por Trematódeos , Animais , Virulência , Interações Hospedeiro-Parasita , Infecções por Trematódeos/parasitologia , Anfíbios/parasitologiaRESUMO
VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory and somatic mutation) syndrome is a novel autoinflammatory, late-onset, disorder first identified in 2020. It is caused by mutations in the UBA1 gene. The most prominent clinical features reported by VEXAS patients are cutaneous and haematological, having characteristic skin features reported as the initial presenting findings of the disease. VEXAS is a severe and treatment-resistant condition with high morbidity and mortality rates. Here, we examine all case reports and case series of VEXAS syndrome through March 2023 focusing on those presenting cutaneous manifestations. We discuss these manifestations and their reported treatment strategies. In many cases, it might be first suspected and diagnosed by dermatologists, highlighting their vital role in initiating timely multidisciplinary care.
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Doenças Hereditárias Autoinflamatórias , Síndromes Mielodisplásicas , Dermatopatias Genéticas , Humanos , Mutação , Pele , Síndrome , Doenças Hereditárias Autoinflamatórias/genética , Doenças Hereditárias Autoinflamatórias/terapiaRESUMO
Lumpy skin disease (LSD) is a highly infectious and economically devastating viral disease of cattle. It is caused by Lumpy Skin Disease Virus (LSDV) belonging to the genus Capripoxvirus and family Poxviridae. The origin of lumpy skin disease has been traced to Zambia, (an African nation) in Southern part during the year 1929. The first reported case of LSD besides Africa was from Israel, a Middle Eastern nation, thus proving inter-continental spread. Subsequently, the disease entered Middle East, Eastern Europe and Asia with numerous outbreaks in the recent years. LSD has emerged as a significant concern in the Indian sub-continent, due to outbreaks reported in countries such as Bangladesh, India, China in 2019. In the following years, other South and East Asian countries like Taipei, Nepal, Sri Lanka, Myanmar, Bhutan, Vietnam, Hong Kong, Thailand, Malaysia, Laos, Cambodia, Pakistan, Indonesia and Singapore also faced severe outbreaks. At present, LSD is considered to be an emerging disease in the Indian sub-continent due to the recent status of disease. Considering the global scenario, LSDV is changing its transmission dynamics as evidenced by a shift in its epidemiology. As a result of high morbidity and mortality rate among cattle, the current outbreaks have been a major cause of socio-economic catastrophe. This contagious viral disease has eminent repercussions as the estimated monetary damage incurred is quite high. Despite having networked surveillance and comprehensive databases, the recurring outbreaks have raised major concern among researchers. Therefore, this review offers brief insights into the emergence of LSDV by amalgamating the newest literature related to its biology, transmission, clinico-pathology, epidemiology, prevention strategies, and economic consequences. Additionally, we have also provided the epidemiological insights of the recent outbreaks with detailed state wise studies.
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Doença Nodular Cutânea , Vírus da Doença Nodular Cutânea , Bovinos , Animais , Vírus da Doença Nodular Cutânea/genética , Doença Nodular Cutânea/epidemiologia , Surtos de Doenças/veterinária , China , Índia/epidemiologiaRESUMO
Riparian formations encompass a diverse suite of transitional zones between terrestrial and aquatic ecosystems. During the last decades, these formations have been impacted by several emerging diseases. The first outbreaks were detected on alder formations, but have progressively also been observed on other plant species such as Betula pubescens, Nerium oleander, Populus alba, Salix alpina, Salix purpurea and Tamarix gallica. Declining plants showed a plethora of symptoms (leaf spot, shoot blight, bleeding cankers and root rot) indicative of Phytophthora infections. Since there is little information about the aetiology of these pathosystems, from November 2019 to March 2023, an in-depth study was conducted in 46 riparian ecosystems spanning from the Mediterranean to Alpine regions. Overall, 744 symptomatic samples (stem bleeding cankers and root with rhizosphere) from 27 host species were collected for Phytophthora isolation. Based on morphology and DNA sequence data, 20 known Phytophthora species belonging to seven phylogenetic clades have been identified: P. plurivora (202 isolates), P. gonapodyides (156), P. pseudosyringae (84), P. lacustris (57), P. acerina (31), P. idaei (30), P. alpina (20), P. pseudocryptogea (19), P. cambivora (13), P. pseudotsugae (13), P. cactorum (9), P. honggalleglyana (6), P. pseudogregata (6), P. debattistii (4), P. multivora (4), P. cinnamomi (3), P. bilorbang (2) P. crassamura (2), P. ilicis (2) and P. inundata (2). In addition, 26 isolates of a new putative species obtained from Alnus incana and Pinus sylvestris are described here as Phytophthora heteromorpha sp. nov. The new species proved to be pathogenic on grey alder causing symptoms congruent with field observations. This study represents the most comprehensive investigation on the Phytophthora species associated with declining riparian vegetation in Italy and highlights that the polyphagous pathogen P. plurivora represents a growing threat to Mediterranean, temperate and alpine ecosystems.
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Ecossistema , Phytophthora , Filogenia , Análise de Sequência de DNA , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Ácidos Graxos/química , Itália , Phytophthora/genéticaRESUMO
BACKGROUND: Cutaneous bacillary angiomatosis (cBA) is a vascular proliferative disorder due to Bartonella spp. that mostly affects people living with HIV (PLWH), transplanted patients and those taking immunosuppressive drugs. Since cBA is mostly related to these major immunocompromising conditions (i.e., T-cell count impairment), it is considered rare in relatively immunocompetent patients and could be underdiagnosed in them. Moreover, antimicrobial treatment in this population has not been previously investigated. METHODS: We searched the databases PubMed, Google Scholar, Scopus, OpenAIRE and ScienceDirect by screening articles whose title included the keywords "bacillary" AND "angiomatosis" and included case reports about patients not suffering from major immunocompromising conditions to provide insights about antibiotic treatments and their duration. RESULTS: Twenty-two cases of cBA not related to major immunocompromising conditions were retrieved. Antibiotic treatment duration was shorter in patients with single cBA lesion than in patients with multiple lesions, including in most cases macrolides and tetracyclines. CONCLUSIONS: cBA is an emerging manifestation of Bartonella spp. infection in people not suffering from major immunocompromising conditions. Until evidence-based guidelines are available, molecular tests together with severity and extension of the disease can be useful to personalize the type of treatment and its duration.
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Angiomatose Bacilar , Antibacterianos , Humanos , Angiomatose Bacilar/tratamento farmacológico , Angiomatose Bacilar/microbiologia , Antibacterianos/uso terapêutico , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Feminino , Adulto , Idoso , Bartonella/efeitos dos fármacosRESUMO
PURPOSE: To investigate the clinical manifestations, management and outcomes of Leishmania lesions in the ear-nose-throat (ENT) region, and its relationship with tumor necrosis factor (TNF)-α blocking drugs. METHODS: Single-center retrospective observational study. Patients diagnosed with cutaneous and mucosal leishmaniasis in the otorhinolaryngologic area at a tertiary referral center over a period of 8 years. RESULTS: Three cases of Leishmania lesions in the ear and two in the nose were encountered at our institution. All patients were under treatment with TNF-α blocking drugs. Diagnosis was challenging, and it was important to have a clinical suspicion in order to use accurate detection techniques. All patients received systemic treatment and achieved a complete resolution of the lesions. CONCLUSIONS: With the increasing use of biologic treatments like TNF-α blockers, this type of infection will be increasingly frequent in endemic areas and also worldwide. It is important to include leishmaniasis in the differential diagnosis of inflammatory/infectious lesions in the ENT region.
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Leishmaniose Cutânea , Leishmaniose , Otolaringologia , Humanos , Fator de Necrose Tumoral alfa , Leishmaniose/diagnóstico , Leishmaniose/tratamento farmacológico , Pele , Estudos Retrospectivos , Leishmaniose Cutânea/terapiaRESUMO
OBJECTIVES: Marburg virus, previously referred to as Marburg hemorrhagic fever, is a highly severe and frequently fatal illness that affects humans. This study aimed to develop and validate a French questionnaire to assess knowledge, attitude, and practice toward Marburg virus disease (FKAP-MVD). STUDY DESIGN: An anonymous online survey was used, which was distributed through various platforms and emails. Data were collected from Burkina Faso, Guinea, the Democratic Republic of Congo, and Senegal. METHODS: To conduct the study, an anonymous online survey was used, which was distributed through various platforms such as Facebook, Twitter, WhatsApp, and emails. The survey was uploaded onto a Google form to facilitate data collection. Data were collected from Burkina Faso, Guinea, the Democratic Republic of Congo, and Senegal. RESULTS: Of the total sample of 510 participants, 60.0% were male, their mean age was 28.41 ± 6.32 years, 38.0% were married, 86.6% resided in urban areas and 64.1% had a university education. The questionnaire had good internal consistency; Cronbach's alpha was 0.87. The correlation between knowledge and attitude was 0.002, the correlation between knowledge and practice was 0.204, and the correlation between practice and attitude was relatively weak and negative at -0.060. This indicates the divergent validity of the questionnaire. The KMO value of 0.91 indicates a high level of adequacy, suggesting that the data are suitable for factor analysis. The Bartlett test of Sphericity yielded an approximate χ2 value of 4016.890 with 300 degrees of freedom and a P-value of 0.0001. The confirmatory factor analysis revealed 25 questions in three domains. The normed chi-square value is 1.224. The goodness of Fit Index (GFI) is 0.902, the Comparative Fit Index (CFI) is 0.982, the Root Mean Square Error of Approximation (RMSEA) is 0.033, and the Root Mean Square Residual (RMR) is 0.062. These values indicate a good fit of the model to the data. CONCLUSIONS: In general, the developed questionnaire has significant potential to inform public health initiatives and interventions related to MVD.
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Doença do Vírus de Marburg , Animais , Humanos , Masculino , Adulto Jovem , Adulto , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Saúde Pública , Inquéritos e Questionários , Reprodutibilidade dos Testes , África Subsaariana , PsicometriaRESUMO
A novel disease affecting small immature fruits has surfaced in 'Saiwaihong' apples (Malus pumila), a recently developed variety extensively cultivated across more than 20,000 hectares in China. In an effort to pinpoint the causal agent(s) responsible for this ailment, RNA sequencing analysis was conducted on four diseased and four healthy apple samples. The results revealed a diverse range of viruses and viroids, indicating a mixed viral infection in diseased samples. However, a more focused examination involving 152 diseased and 122 healthy fruit samples, utilizing RT-PCR and dot-blotting hybridization techniques, highlighted a close association between the disease and the presence of apple scar skin viroid (ASSVd). Among the obtained ASSVd variants from diseased 'Saiwaihong' apples, 20 were identified, and they were either identical or closely related to isolates from various apple varieties cultivated in different regions and countries. This suggests that ASSVd isolates in 'Saiwaihong' might have been introduced from other apple varieties. Furthermore, the analysis indicates the possibility of two separate introductions, as the ASSVd 'Saiwaihong' isolates demonstrated two distinct phylogenetic groups. These insights provide valuable guidance for disease control strategies and emphasize the significance of ongoing monitoring for ASSVd, both in its familiar forms and potential new variants.
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Wheat (Triticum aestivum) loses 21.5% yield to pests and diseases annually (Savary et al. 2019). Among the wheat diseases, bacterial leaf streak (BLS) is a growing problem, costing $78.5 million in losses (https://cropprotectionnetwork.org/). In July 2022, we sampled winter wheat leaf samples at Volga (44.30, -96.92), South Dakota, USA with an estimated disease incidence of 40% (n=100). The typical symptoms were water-soaking with large necrotic and chlorotic streaks extending the length of the leaves and were strikingly similar to BLS. To isolate the pathogen, leaves were cut lengthwise into 1 cm pieces and surface-sterilized using a 10% NaOCl solution for 3 min, followed by 70% ethanol for 3 min, and then rinsed with sterile distilled water and placed in 500 ul of sterile distilled water for 5 min and using a sterile loop the water was streaked over a plate of Nutrient Agar (NA). Following Duveiller et al. (1997), the streaked plate was incubated in the dark at 28â for 48 h. Observed single colonies were sub-cultured thrice onto fresh NA plates to obtain a pure culture. We named the culture SD101. Bacteria were found to be gram-negative with a colony morphology initially raised, smooth, and white that later turned yellow. DNA was extracted using the Wizard HMW DNA Extraction Kit (Promega, Madison, WI) following the manufacturer's protocol, and sequenced using Nanopore MinION R9.4 (Oxford Nanopore Technology). We used the Rapid Annotation Using Subsystems Technology approach (Aziz eal. 2008) to extract the 16S rDNA, DNA gyrase subunit B (gyrB), and translation initiation factor IF-2 (infB) gene sequences that were deposited in GenBank under accession numbers PP329908.1 for 16S rDNA, PP496481 for infB, and PP328920.1 for gyrB. Homology analysis using CLC Genomics Workbench 22.0.2 (QIAGEN) and BLASTn against the GenBank nucleotide database resulted in a 99.74% match (1543/ 1547 bp) of the 16S sequence, 99.59% match (2674/ 2685 bp) of the infB sequence, and 99.42% match (2396/ 2410 bp) of the gyrB sequence with Pantoea ananatis strain AJ13355 (AP012032). To test pathogenicity, seeds of spring wheat breeding line SD4892 were planted in 30 cm × 30 cm pots in a greenhouse under a 16 h light photoperiod. The inoculum was prepared from 48-h-old NA plates of SD101 rinsed with 1X Phosphate Buffer Saline (PBS buffer), adjusted to an OD600 = 1.0, and amended with two drops of Tween 20 (polyoxyethylene sorbitol ester, Millipore Sigma). PBS with Tween 20 was used as a negative control. The inoculum was sprayed on 15 replicates of 15-day-old seedlings, kept at 95% relative humidity for 48 h, then moved to the greenhouse at 23 to 25°C. The symptoms appeared as water soaking that later turned to necrotic streaks with surrounding chlorosis on all 15 inoculated plants while control plants remained healthy. The pathogen was re-isolated from the leaves as described above. The 16S rDNA, infB, and gyrB sequences amplified and sequenced were identical to the gene sequences from the whole genome sequencing. The experiment was repeated with the same results, completing Koch's postulates. Although P. ananatis is pathogenic on corn, rice, and other plant species in the United States (Coutinho et al. 2009), and was reported pathogenic on wheat in Poland (Krawczyk et al. 2020), this is the first report of its pathogenicity on wheat in the United States. The prevalence, and incidence of BLS disease caused by P. ananatis in wheat is needed to estimate its threat to wheat production and to develop management strategies.
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Anthracnose, a destructive fungal disease, poses a significant threat to chili pepper (Capsicum annuum L.) production worldwide (de Silva et al. 2019). In South Korea, anthracnose outbreaks have traditionally been attributed to several Colletotrichum species such as C. gloeosporioides and C. acutatum. About 10% of the yield (chili production) is lost annually in South Korea due to chili anthracnose (Oo et al. 2020). During field surveys conducted in August 2017, symptomatic lesions resembling anthracnose were observed on chili pepper in two farmer's fields (Gochang and Cheongyang) in South Korea. Affected fruits exhibited characteristic symptoms, including circular sunken lesions with dark margins and abundant orange spore masses on the surface. About 20% of chili pepper fruit were affected in each field with an area of about 0.2 ha. Five putative Colletotrichum spp. isolates were obtained from six affected fruits (three from each field) following the procedure described by Cai et el. (2009). Three isolates (C01049, C01111, and C01115), representing each location, were selected to identify at the species level. Colonies on potato dextrose agar (incubated at 25°C in the dark for 7 days) were cottony with entire margins, white aerial mycelium and dark gray in the center. Conidia were hyaline, aseptate, cylindrical with bothnds round, and 17.8 - 30.5 × 6.0 -10.0 µm (mean 23.8 ×7.9 µm, n = 30). Appressoria were dark brown, irregular but mostly ovoid with smooth walls. These morphological features align with those of Colletotrichum spp. within the Colletotrichum gigasporum species (Liu et al. 2014). The identity of the pathogen was further confirmed through multi-locus phylogenetic analysis. The target genes including ITS, ACT, CHS-1, GAPDH, TUB2, and GS were amplified and sequenced using the primer sets ITS1/ITS4, ACT 512F/ ACT-783R, CHS-79F/ CHS-345R, GDF/GDR, T1/Bt2b, and GSF1/GSR1, respectively (Weir et al. 2012; Liu et al. 2014). The resulting sequences were deposited in GenBank (accession no: ITS: MT605261, MT605262, LC823714; ACT: MT612991, MT612992, LC823718; CHS-1: MT612993, MT612994, LC823717; GAPDH: LC811375, LC811376, LC823716; TUB2: MT612997, MT612998, LC823715; GS: LC811377, LC811378, LC823719). The constructed Bayesian and maximum likelihood tree based on combined sequences of ITS, ACT, CHS-1, GAPDH, TUB2, and GS confirmed the identification of the isolates (C01049, C01111, C01115) as C. gigasporum. Pathogenicity tests were conducted by inoculating healthy chili fruit with 70 µL of a conidial suspension (1×106 conidia /mL) of pure cultures of the isolates. The conidial suspension was applied on 10 wounded or 10 non-wounded fruit. The same number of fruit were treated with sterile distilled water as controls. Within 5 days of inoculation, symptoms consistent with anthracnose developed on the inoculated wounded fruit, whereas non-wounded and control fruit remained asymptomatic. This experiment was repeated twice. Colletotrichum gigasporum was re-isolated from diseased tissue of inoculated fruit. Colletotrichum gigasporum has been identified as the cause of anthracnose on Dalbergia odorifera, Carica papaya in China, and Brassica oleracea in India (Wan et al., 2018; Saini et al. 2022; He et al. 2023). To the best of our knowledge, this report marks the first documented instance of C. gigasporum causing anthracnose of chili pepper in South Korea. These results indicate that various species of Colletotrichum can be the fungi causing chili pepper anthracnose. The findings of this study emphasize the need for effective disease management strategies to mitigate impact of C. gigasporum on chili pepper cultivation in the region.
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Wheat (Triticum aestivum) is an important crop worldwide, contributing to about one third of the global caloric intake. In June 2021, leaves with bacterial blight symptoms, including yellow and necrotic lesions running parallel to veins, were found in several fields across five counties in eastern Colorado (Weld, Morgan, Sedgwick, Baca, and Kit Carson). Plants exhibiting these symptoms were scattered throughout fields, but symptoms appeared consistent across counties. To determine the causal agent and complete Koch's postulates, a 1 cm2 symptomatic leaf area was excised and macerated in 0.5 mL of sterilized water from four field samples. The lysate was spread on yeast extract dextrose calcium carbonate medium (YDC agar, 1% yeast extract, 2% dextrose, 2% calcium carbonate, 1.5% agar) to isolate bacteria. Single colonies of yellow, mucoid morphology were selected and streaked on new YDC plates. Isolate genomic DNA was extracted (Zymo Research Quick-DNA Fungal/Bacterial Miniprep Kit, #D6005), and ~30 ng of gDNA was used to amplify the 16S rRNA, gyrB, and rpoB genes of all four isolates (Barret et al., 2015; Delétoile et al., 2009; Krawczyk et al., 2020; Ogier et al., 2019). Amplified PCR products were cleaned (Zymo DNA Clean & Concentrator kit, #D4033) and Sanger sequenced, and all sequences have been deposited in NCBI (16S rRNA: OR707336, OR707337, OR707338, OR707339), (gyrB: PP407951, PP407952, PP407953, PP407954), (rpoB: PP407955, PP407956, PP407957, PP407958). A BLAST search against whole genomes identified one isolate from Kit Carson county (CO314) and two isolates from Baca county (CO316 and CO317) as Pantoea agglomerans with 100% identity for the 16S rRNA, gyrB, and rpoB genes, and one isolate from Weld county (CO315) was 100% identical to Pantoea allii for all three genes. To complete Koch's postulates and confirm Pantoea sp. as the causal disease agents, isolates were grown as lawns on DifcoTM Nutrient Agar (NA) medium (48h, 28â), suspended in 10 mM MgCl2 using a final optical density of 0.1 (~109 colony forming units per milliliter (CFU/mL)), and syringe-infiltrated into the entire leaf area of 10-day-old wheat seedling leaves (var. Hatcher). Treatments of 10mM MgCl2 and a field isolate that does not cause symptoms, identified as Pseudomonas synxantha by 16S rRNA and gyrB sequencing, were negative controls. Inoculated wheat plants were transferred to a growth chamber (22â, 90% relative humidity). Symptoms developed 14 days post inoculation (dpi), with the most severe appearing 21 dpi. Each of the four Pantoea isolates were re-isolated from symptomatic leaves by grinding them in a Tissue Lyser II (Qiagen) with two metal beads and diluting with 0.4 mL of sterile water. A 20 µL sample of each isolate was plated on NA (24h, 28â). The colonies appeared phenotypically identical to the original isolates, and Sanger sequencing confirmed the identities of the isolates. To our knowledge, this is the first report of P. agglomerans causing disease in wheat in the United States, and the first report of P. allii as a wheat disease-causing agent. This report is consistent with previous communications showing P. agglomerans causing wheat disease in China (Gao et al., 2023), and P. ananatis in Poland (Krawczyk et al., 2020). The growing numbers of reports of Pantoea spp. as pathogens in recent years suggests increasing novel disease emergence on cereals worldwide.
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In May 2023, pennycress (Thlaspi arvense, L.) lines undergoing seed production in the Walnut Street Greenhouse at the University of Wisconsin-Madison displayed symptoms of chlorosis and black necrotic leaf spots (Fig. S1-A). Lesions eventually enlarged to 1-2 cm in diameter, became necrotic, and coalesced to cover a substantial portion of leaves. Symptoms were observed in ~30% of the pennycress lines adversely affecting overall growth and reproduction. Symptomatic leaves were surface sterilized for 30 seconds in 0.75% sodium hypochlorite, rinsed in sterile deionized water, and bacteria were isolated using three-phase streaking of symptomatic tissue onto KB medium (King et al., 1954). Single colonies of three isolates (creamy white to yellow) from this initial isolation were streaked onto KB medium to obtain pure cultures. Individual colonies were transferred for growth overnight in nutrient broth (Difco) and an equal amount of the broth was added to 30% glycerol in deionized (di) water and stored at -80 °C. To validate Koch's Postulates, bacteria were grown from these stocks on Yeast Dextrose Calcium Carbonate medium (Wilson et al., 1967) and were used to inoculate 5-week-old pennycress plants in the greenhouse. The bacteria were grown for 48 hours at 26°C, suspended in 300 ml of 0.05 M PBS buffer (pH=7.2) for inoculum preparation. Plants were inoculated with three bacterial isolates (approx. 108 CFU/ml) by piercing the mid veins or hydathodes with a sterilized toothpick dipped in the suspension. Inoculated plants were then enclosed in clear plastic bags for 24-48 hours and maintained in the greenhouse at a constant temperature of 26°C with a 16-hour photoperiod. After seven days, water-soaked lesions appeared on the inoculated leaves, eventually developing into the characteristic black spots (Fig. S1-B). DNA from the original isolates was extracted, and 16S PCR and sequencing of the positive bands was done. The negative control only produced brown spots at the site of inoculation (Fig. S1-C). The primer sequences were as follows: 27F: AGAGTTTGATCMTGGCTCAG; 1492R: GGTTACCTTGTTACGACTT (Eden et al., 1991; Weisburg et al., 1991). A BLAST analysis showed that the isolates had an E value of 0.0 to the genus Xanthomonas as well as 100% identity. Amplification and sequencing of the bacterium using gyrB amplicons revealed a 99-100% pairwise match with Xc. To enhance taxonomy resolution and confirm the identity of these isolates, the complete genomes of three samples were sequenced using NextSeq2000 Illumina platform (NCBI bioproject ID PRJNA1040293). Average Nucleotide Identity (ANI) analysis was conducted with representative strains from the Xc species (Dubrow et al., 2022), using PanExplorer (Dereeper et al., 2020) featuring integrated FastANI module (Jain et al., 2018). The isolates genomes exhibited over 98% identity and clustered with that of Xc pv. incanae and Xc pv. barbarae (Fig S2). Further work will be required to identify the pathovar of Xc identified in this study through phenotypic host range assay. This marks the first documented case of Xc in pennycress in the Midwestern US. Given the potential use of pennycress as a cover crop in the region, further investigations are warranted to assess its economic impact on production and develop management strategies.
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Tularemia is increasing in Austria. We report Francisella tularensis subspecies holarctica isolated from 3 patients who had been bitten by arthropods. Next-generation sequencing showed substantial isolate similarity. Clinicians should consider bloodstream F. tularensis infections for patients with signs/symptoms of ulceroglandular tularemia, and surveillance of potential vectors should be intensified.
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Mordeduras e Picadas , Francisella tularensis , Tularemia , Humanos , Tularemia/diagnóstico , Tularemia/epidemiologia , Francisella tularensis/genética , Áustria/epidemiologiaRESUMO
Domesticated honeybees and wild bees are some of the most important beneficial insects for human and environmental health, but infectious diseases pose a serious risk to these pollinators, particularly following the emergence of the ectoparasitic mite Varroa destructor as a viral vector. The acquisition of this novel viral vector from the Asian honeybee Apis ceranae has fundamentally changed viral epidemiology in its new host, the western honeybee A. mellifera. While the recently discovered Lake Sinai Viruses (LSV) have been associated with weak honeybee colonies, they have not been associated with vector-borne transmission. By combining a large-scale multi-year survey of LSV in Chinese A. mellifera and A. cerana honeybee colonies with globally available LSV-sequence data, we investigate the global epidemiology of this virus. We find that globally distributed LSV is a highly diverse multi-strain virus, which is predominantly associated with the western honeybee A. mellifera. In contrast to the vector-borne deformed wing virus, LSV is not an emerging disease. Instead, demographic reconstruction and strong global and local population structure indicates that it is a highly variable multi-strain virus in a stable association with its main host, the western honeybee. Prevalence patterns in China suggest a potential role for migratory beekeeping in the spread of this pathogen, demonstrating the potential for disease transmission with the man-made transport of beneficial insects.
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Abelhas , Vírus de RNA , Varroidae , Animais , Humanos , Abelhas/parasitologia , Abelhas/virologia , China/epidemiologia , Vírus de RNA/genética , Varroidae/virologia , VírusRESUMO
Mycopathogenic bacteria play a pivotal role in the productivity of edible mushrooms grown under controlled conditions. In this study, we carried out a comprehensive farm survey and sampling (2018 to 2021) on button mushroom (Agaricus bisporus) farms in 15 provinces in Iran to monitor the status of bacterial pathogens infecting the crop. Mycopathogenic bacterial strains were isolated from pins, stems, and caps, as well as the casing layer on 38 mushroom farms. The bacterial strains incited symptoms on mushroom caps ranging from faint discoloration to dark brown and blotch of the inoculated surfaces. Among the bacterial strains inciting disease symptoms on bottom mushroom, 40 were identified as Ewingella americana based on biochemical assays and phylogeny of 16S rRNA and the gyrB gene. E. americana strains differed in their aggressiveness on mushroom caps and stipes, where the corresponding symptoms ranged from deep yellow to dark brown. In the phylogenetic analyses, all E. americana strains isolated in this study were clustered in a monophyletic clade closely related to the nonpathogenic and environmental strains of the species. BOX-PCR-based fingerprinting revealed intraspecific diversity. Using the cutoff level of 73 to 76% similarity, the strains formed six clusters. A chronological pattern was observed, where the strains isolated in 2018 were differentiated from those isolated in 2020 and 2021. Taken together, due to the multifaceted nature of the pathogen, such a widespread occurrence of E. americana on mushroom farms in Iran could be an emerging threat for the mushroom industry in the country.
Assuntos
Enterobacteriaceae , Doenças das Plantas , Filogenia , RNA Ribossômico 16S/genética , Enterobacteriaceae/genética , Bactérias/genéticaRESUMO
Mycobacterium infection in fish is a well-known disease problem globally, mainly in the farming of ornamental fish or fish for food. Less is known about the prevalence, distribution and the effects such infections have on wild fish species. Presumptive mycobacteriosis has previously been observed in Atlantic mackerel (Scomber scombrus). Since 2018, there has been an increase in reports of granulomatous kidney disease in Atlantic mackerel with the suspicion of this being mycobacteriosis. A total of six individuals were sent to the Institute of Marine Research for further examination. They were caught in the Nordic Sea by either commercial fishing vessels or during the International Ecosystem Summer Survey in the Nordic Seas (IESSNS research cruise) between 2018 and 2020. Samples for both histological and molecular analysis were collected. Here, we detect a likely novel Mycobacterium species in tissue samples from Atlantic mackerel with this condition, on the basis of rDNA and protein gene sequences. The same unnamed bacterium seems to have been found in some Pacific marine fishes. The macroscopic and histological manifestation of the disease is described. Over the past years, there has been an increase in reports of mycobacteriosis worldwide and climate change has been suggested as one of the driving forces as these bacteria prefer warm water.
Assuntos
Doenças dos Peixes , Infecções por Mycobacterium , Perciformes , Animais , Ecossistema , Oceanos e Mares , Bactérias , Perciformes/genéticaRESUMO
Blackberry (Rubus L. subgenus Rubus Watson) is a deciduous berry crop that is the fourth most economically important berry crop, and its production is expanding in the southeastern United States. However, since most commercially available cultivars were bred under temperate conditions, they are not always well adapted and could be threatened by new pathogen populations inhabiting subtropical areas. In 2017, plants showing purple or brown leaf spots and angular-to-irregular lesions on both leaf surfaces, with clusters of black conidiophores at the center, were observed in a field trial at the University of Florida's Gulf Coast Research and Education Center (UF/GCREC) in Wimauma, FL. A fungus resembling Cercospora/Pseudocercospora was isolated from the lesions. The ribosomal DNA internal transcribed spacers, the translation elongation factor 1-alpha, and the actin genes were amplified and sequenced. Based on the phylogenetic analysis, the closest related species was Pseudocercospora pancratii. Pathogenicity assays and subsequent reisolation confirmed that this species is the causal agent of the disease. Among eight cultivars screened, no complete resistance was found. However, 'Osage' was the least susceptible, and 'Kiowa' was the most susceptible. This study is the first report of P. pancratii causing leaf spots on blackberry worldwide, and it may help shape future research into disease epidemiology and management for a crop that is rapidly expanding but has very limited disease information currently available for Florida growers.
Assuntos
Ascomicetos , Rubus , Florida , Filogenia , Melhoramento VegetalRESUMO
Strawberry root and crown rot caused by the fungus Neopestalotiopsis rosae is an emerging disease that has caused yield losses reaching 70% in Mexico and other regions worldwide. This research evaluated the effects of biological and chemical fungicides applied as preventive and curative applications for controlling root and crown rot caused by N. rosae in strawberries under greenhouse conditions. Treatments included these chemical fungicides: prochloraz, prochloraz+thiram, cyprodinil+fludioxonil, difenoconazole+azoxystrobin, iprodione, captan, thiram, pydiflumetofen+fludioxonil, fluxapyroxad+pyraclostrobin, and hymexazol; each applied at commercial doses. Also tested were biological treatments based on Trichoderma koningiopsis, Trichoderma asperellum, Streptomyces sp., and Bacillus amyloliquefaciens strain D747 (B. velezensis). Disease incidence, severity, plant mortality, root length, and dry weight were determined. Results showed that overall, preventive applications of the fungicides pydiflumetofen+fludioxonil, cyprodinil+fludioxonil, and prochloraz resulted in the smallest area under the disease progress curve, and lowest final disease incidence, severity, and plant mortality. An intermediate group of effective treatments entailed hymexazol, iprodione, T. asperellum, and T. koningiopsis (50-75% efficacy). Treatments with greater efficacy (99 to 100%), prochloraz pydiflumetofen+fludioxonil, cyprodinil+fludioxonil, and prochloraz, also had maximal total plant biomass vis-à-vis the untreated control. In contrast, each treatment's efficacy was significantly reduced when applied curatively (0 to 37% treatment efficacy). These results suggest that certain treatments are useful for controlling strawberry root and crown rot caused by N. rosae, when applied preventively (as root dipping). These results will contribute to design more effective management programs of root rot and crown rot caused by N. rosae on strawberry.
RESUMO
BACKGROUND & OBJECTIVES: Emerging zoonotic and vector-borne diseases are posing new challenges to public health authorities. Morbidities and mortalities due to acute encephalitis syndrome (AES) is a serious health problem in paediatric patients. We conducted serological investigations on AES cases from six districts of north eastern Madhya Pradesh (MP), India for Japanese encephalitis (JE). METHODS: The paired serum and CSF samples were collected from paediatric patients having signs and symptoms of encephalitis and admitted at a tertiary care hospital during the study period from August 2020 to October 2021. Demographic and clinical information was collected in predesigned formats. Serum and CSF were subjected to JE IgM specific ELISA. RESULTS: Samples from 110 patients were collected during the study period of which 28 (25.4%) were reactive for JE IgM antibodies. JE IgM positivity was marginally higher in male children (26.6%) as compared to female children (22.8%). Out of 28 positive cases, 11 (39.2%) deaths were attributed to JE. Four districts of north eastern Madhya Pradesh showed JE activity. Maximum cases were observed in post-monsoon season. INTERPRETATION & CONCLUSION: Our results show that JEV is an emerging threat in eastern central India and health authorities need to be vigilant. A systematic molecular and serological survey among humans and animals along with xenomonitoring will help in understanding intricacies of JE epidemiology in the region.