Patterns of infection, origins and transmission of ranaviruses among the ectothermic vertebrates of Asia

Ranaviral infections, a malady of ectothermic vertebrates, are becoming frequent, severe, and widespread, causing mortality among both native and cultured species, raising odds of species extinctions and economic losses. This turn of events is possibly due to the broad host range of ranaviruses and the transmission of these pathogens through regional and international trade in Asia, where outbreaks have been increasingly reported over the past decade. Here we focus attention on the origins, means of transmission, and patterns of spread of this infection within the region. Infections have been recorded in both cultured and wild populations in at least twelve countries/administrative regions, together with mass die-offs in some regions. Despite the imminent seriousness of the disease in Asia, surveillance efforts are still incipient. Some of the infections transmitted within Asia may transmit across host-taxon barriers, posing a significant risk to native species. Factors such as rising temperatures due to global climate change seem to exacerbate ranaviral activity, as most known outbreaks have been recorded during summer; however, data are still inadequate to verify this for Asia. Import risk analysis, using protocols such as Pandora+, pre-border pathogen screening, and effective biosecurity measures, can be used to mitigate introduction to uninfected areas and curb transmission within Asia. Comprehensive surveillance using molecular diagnostic tools for ranavirus species and variants will help in understanding the prevalence and disease burden in the region. This is an important step towards conserving native biodiversity and safeguarding the aquaculture industry.

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Frequency of benzimidazole resistance inHaemonchus contortus populations isolated from buffalo, goat and sheep herds

Revista Brasileira de Parasitologia Veterinária ◽

10.1590/s1984-29612013000400015 ◽

2013 ◽

Vol 22 (4) ◽

pp. 548-553 ◽

Cited By ~ 12

Author(s):

Ronaldo Luiz Nunes ◽

Livia Loiola dos Santos ◽

Eduardo Bastianetto ◽

Denise Aparecida Andrade de Oliveira ◽

Bruno Santos Alves Figueiredo Brasil

Keyword(s):

Haemonchus Contortus ◽

Significant Variation ◽

Genetic Basis ◽

Anthelmintic Resistance ◽

Allelic Frequency ◽

Molecular Diagnostic ◽

Economic Losses ◽

Diagnostic Tools ◽

Ruminant Species ◽

Benzimidazole Resistance

Anthelmintic resistance is an increasing problem that threatens livestock production worldwide. Understanding of the genetic basis of benzimidazole resistance recently allowed the development of promising molecular diagnostic tools. In this study, isolates of Haemonchus contortus obtained from goats, sheep and buffaloes raised in Brazil were screened for presence of the polymorphism Phe200Tyr in the β-tubulin 1 gene, which confers resistance to benzimidazole. The allelic frequency of the mutation conferring resistance ranged from 7% to 43%, and indicated that resistance to benzimidazole could be found in nematodes isolated from all the ruminant species surveyed. Although significant variation in the frequency of the F200Y mutation was observed between different herds or host species, no significant variation could be found in populations isolated from animals within the same herd. These findings suggest that screening of samples from a few animals has the potential to provide information about the benzimidazole resistance status of the entire herd, which would enable a considerable reduction in the costs of diagnosis for the producer. Molecular diagnosis has practical advantages, since it can guide the choice of anthelmintic drug that will be used, before its application in the herd, thus reducing the economic losses driven by anthelmintic resistance.

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Global Distribution and Genetic Heterogeneity of Border Disease Virus

Viruses ◽

10.3390/v13060950 ◽

2021 ◽

Vol 13 (6) ◽

pp. 950

Author(s):

Cecilia Righi ◽

Stefano Petrini ◽

Ilaria Pierini ◽

Monica Giammarioli ◽

Gian Mario De Mia

Keyword(s):

Disease Virus ◽

Significant Risk ◽

Small Ruminants ◽

Control Measures ◽

Interspecies Transmission ◽

Economic Losses ◽

Border Disease Virus ◽

Diarrhea Virus ◽

Geographical Regions ◽

Border Disease

Border disease virus (BDV) belongs to the genus Pestivirus of the family Flaviviridae. Interspecies transmission of BDV between sheep, cattle, and pigs occurs regularly, sometimes making diagnosis a challenge. BDV can yield substantial economic losses, including prenatal and postnatal infections in lambs, which are the primary source of infection and maintenance of the virus in the population. Since BDV is antigenically and genetically related to bovine viral diarrhea virus (BVDV), it might pose a significant risk to cattle, influencing BVDV eradication campaigns. Similarly, the presence of BDV in swine herds due to pestivirus spillover between small ruminants and pigs might cause uncertainty in classical swine fever virus (CSFV) diagnostics. Therefore, knowledge of BDV epidemiology in different geographical regions will help prevent its spread and optimize control measures. Previous epidemiological studies have shown that various BDV genotypes are predominant in different countries. This review provides an overview of the spread of BDV world-wide in different host species.

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Development of a loop-mediated isothermal amplification (LAMP) assay for the identification of the invasive wood borer Aromia bungii (Coleoptera: Cerambycidae) from frass

3 Biotech ◽

10.1007/s13205-020-02602-w ◽

2021 ◽

Vol 11 (2) ◽

Author(s):

Domenico Rizzo ◽

Nicola Luchi ◽

Daniele Da Lio ◽

Linda Bartolini ◽

Francesco Nugnes ◽

...

Keyword(s):

Lamp Assay ◽

Isothermal Amplification ◽

Molecular Diagnostic ◽

Diagnostic Tools ◽

Loop Mediated Isothermal Amplification ◽

Larval Stages ◽

Longhorn Beetle ◽

Rapid Monitoring ◽

Major Pest ◽

Wood Borer

AbstractThe red-necked longhorn beetle Aromia bungii (Faldermann, 1835) (Coleoptera: Cerambycidae) is native to east Asia, where it is a major pest of cultivated and ornamental species of the genus Prunus. Morphological or molecular discrimination of adults or larval specimens is required to identify this invasive wood borer. However, recovering larval stages of the pest from trunks and branches causes extensive damage to plants and is timewasting. An alternative approach consists in applying non-invasive molecular diagnostic tools to biological traces (i.e., fecal pellets, frass). In this way, infestations in host plants can be detected without destructive methods. This paper presents a protocol based on both real-time and visual loop-mediated isothermal amplification (LAMP), using DNA of A. bungii extracted from fecal particles in larval frass. Laboratory validations demonstrated the robustness of the protocols adopted and their reliability was confirmed performing an inter-lab blind panel. The LAMP assay and the qPCR SYBR Green method using the F3/B3 LAMP external primers were equally sensitive, and both were more sensitive than the conventional PCR (sensitivity > 103 to the same starting matrix). The visual LAMP protocol, due to the relatively easy performance of the method, could be a useful tool to apply in rapid monitoring of A. bungii and in the management of its outbreaks.

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The new Internal Transcribed Spacer 2 diagnostic tool clarifies the taxonomic position and geographic distribution of the North American malaria vector Anopheles punctipennis

Malaria Journal ◽

10.1186/s12936-021-03676-4 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

James M. Hodge ◽

Andrey A. Yurchenko ◽

Dmitriy A. Karagodin ◽

Reem A. Masri ◽

Ryan C. Smith ◽

...

Keyword(s):

Malaria Vector ◽

Internal Transcribed Spacer ◽

Single Species ◽

Its2 Sequence ◽

Pathogen Transmission ◽

Molecular Diagnostic ◽

Diagnostic Tools ◽

Sequence Length ◽

Phylogenetic Position ◽

Internal Transcribed Spacer 2

Abstract Background The malaria mosquito Anopheles punctipennis, a widely distributed species in North America, is capable of transmitting human malaria and is actively involved in the transmission of the ungulate malaria parasite Plasmodium odocoilei. However, molecular diagnostic tools based on Internal Transcribed Spacer 2 (ITS2) of ribosomal DNA are lacking for this species. Anopheles punctipennis is a former member of the Anopheles maculipennis complex but its systematic position remains unclear. Methods In this study, ITS2 sequences were obtained from 276 An. punctipennis specimens collected in the eastern and midwestern United States and a simple and robust Restriction Fragment Length Polymorphism approach for species identification was developed. The maximum-likelihood phylogenetic tree was constructed based on ITS2 sequences available through this study and from GenBank for 20 species of Anopheles. Results The analysis demonstrated a consistent ITS2 sequence length and showed no indications of intragenomic variation among the samples based on ITS2, suggesting that An. punctipennis represents a single species in the studied geographic locations. In this study, An. punctipennis was found in urban, rural, and forest settings, suggesting its potential broad role in pathogen transmission. Phylogeny based on ITS2 sequence comparison demonstrated the close relationship of this species with other members of the Maculipennis group. Conclusions This study developed molecular tools based on ITS2 sequences for the malaria vector An. punctipennis and clarified the phylogenetic position of the species within the Maculipennis group.

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LAMP in Neglected Tropical Diseases: A Focus on Parasites

Diagnostics ◽

10.3390/diagnostics11030521 ◽

2021 ◽

Vol 11 (3) ◽

pp. 521

Author(s):

Juan García-Bernalt Diego ◽

Pedro Fernández-Soto ◽

Antonio Muro

Keyword(s):

Neglected Tropical Diseases ◽

Treatment Success ◽

Public Health Problem ◽

Nucleic Acid Amplification ◽

Molecular Diagnostic ◽

Diagnostic Tools ◽

World Population ◽

Major Public Health Problem ◽

Tropical Diseases ◽

Early 21St Century

Neglected Tropical Diseases (NTDs), particularly those caused by parasites, remain a major Public Health problem in tropical and subtropical regions, with 10% of the world population being infected. Their management and control have been traditionally hampered, among other factors, by the difficulty to deploy rapid, specific, and affordable diagnostic tools in low resource settings. This is especially true for complex PCR-based methods. Isothermal nucleic acid amplification techniques, particularly loop-mediated isothermal amplification (LAMP), appeared in the early 21st century as an alternative to PCR, allowing for a much more affordable molecular diagnostic. Here, we present the status of LAMP assays development in parasite-caused NTDs. We address the progress made in different research applications of the technique: xenomonitoring, epidemiological studies, work in animal models and clinical application both for diagnosis and evaluation of treatment success. Finally, we try to shed a light on the improvements needed to achieve a true point-of-care test and the future perspectives in this field.

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A 2.8-Angstrom-Resolution Cryo-Electron Microscopy Structure of Human Parechovirus 3 in Complex with Fab from a Neutralizing Antibody

Journal of Virology ◽

10.1128/jvi.01597-18 ◽

2018 ◽

Vol 93 (4) ◽

Cited By ~ 5

Author(s):

Aušra Domanska ◽

Justin W. Flatt ◽

Joonas J. J. Jukonen ◽

James A. Geraets ◽

Sarah J. Butcher

Keyword(s):

Electron Microscopy ◽

Monoclonal Antibody ◽

High Resolution ◽

Cultured Cells ◽

Human Monoclonal Antibody ◽

Neutralizing Antibody ◽

Molecular Diagnostic ◽

Diagnostic Tools ◽

Human Parechovirus ◽

Cryo Electron Microscopy

ABSTRACTHuman parechovirus 3 (HPeV3) infection is associated with sepsis characterized by significant immune activation and subsequent tissue damage in neonates. Strategies to limit infection have been unsuccessful due to inadequate molecular diagnostic tools for early detection and the lack of a vaccine or specific antiviral therapy. Toward the latter, we present a 2.8-Å-resolution structure of HPeV3 in complex with fragments from a neutralizing human monoclonal antibody, AT12-015, using cryo-electron microscopy (cryo-EM) and image reconstruction. Modeling revealed that the epitope extends across neighboring asymmetric units with contributions from capsid proteins VP0, VP1, and VP3. Antibody decoration was found to block binding of HPeV3 to cultured cells. Additionally, at high resolution, it was possible to model a stretch of RNA inside the virion and, from this, identify the key features that drive and stabilize protein-RNA association during assembly.IMPORTANCEHuman parechovirus 3 (HPeV3) is receiving increasing attention as a prevalent cause of sepsis-like symptoms in neonates, for which, despite the severity of disease, there are no effective treatments available. Structural and molecular insights into virus neutralization are urgently needed, especially as clinical cases are on the rise. Toward this goal, we present the first structure of HPeV3 in complex with fragments from a neutralizing monoclonal antibody. At high resolution, it was possible to precisely define the epitope that, when targeted, prevents virions from binding to cells. Such an atomic-level description is useful for understanding host-pathogen interactions and viral pathogenesis mechanisms and for finding potential cures for infection and disease.

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The burden of congenital Chagas disease and implementation of molecular diagnostic tools in Latin America

BMJ Global Health ◽

10.1136/bmjgh-2018-001069 ◽

2018 ◽

Vol 3 (5) ◽

pp. e001069 ◽

Cited By ~ 21

Author(s):

Albert Picado ◽

Israel Cruz ◽

Maël Redard-Jacot ◽

Alejandro G Schijman ◽

Faustino Torrico ◽

...

Keyword(s):

Latin America ◽

Chagas Disease ◽

Diagnostic Algorithm ◽

Diagnostic Methods ◽

Diagnosis And Treatment ◽

Molecular Diagnostic ◽

Diagnostic Tools ◽

Molecular Tests ◽

Epidemiological Impact ◽

And Performance

It is estimated that between 8000 and 15 000 Trypanosoma cruzi infected babies are born every year to infected mothers in Chagas disease endemic countries. Currently, poor access to and performance of the current diagnostic algorithm, based on microscopy at birth and serology at 8–12 months after delivery, is one of the barriers to congenital Chagas disease (CCD) control. Detection of parasite DNA using molecular diagnostic tools could be an alternative or complement to current diagnostic methods, but its implementation in endemic regions remains limited. Prompt diagnosis and treatment of CCD cases would have a positive clinical and epidemiological impact. In this paper, we analysed the burden of CCD in Latin America, and the potential use of molecular tests to improve access to early diagnosis and treatment of T. cruzi infected newborns.

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Identification of pathogenic Leptospira species and serovars in New Zealand using metabarcoding

PLoS ONE ◽

10.1371/journal.pone.0257971 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0257971

Author(s):

David A. Wilkinson ◽

Matthew Edwards ◽

Jackie Benschop ◽

Shahista Nisa

Keyword(s):

New Zealand ◽

Diagnostic Techniques ◽

Molecular Diagnostic ◽

Diagnostic Tools ◽

Pathogenic Leptospira ◽

Molecular Barcoding ◽

Sequencing Platform ◽

Oxford Nanopore ◽

Culture Independent ◽

Variant Identification

Leptospirosis is a zoonotic disease of global importance. The breadth of Leptospira diversity associated with both human and animal disease poses major logistical challenges to the use of classical diagnostic techniques, and increasingly molecular diagnostic tools are used for their detection. In New Zealand, this has resulted in an increase in positive cases reported nationally that have not been attributed to the infecting serovar or genomospecies. In this study, we used data from all pathogenic Leptospira genomes to identify a partial region of the glmU gene as a suitable locus for the discrimination of the infecting species and serovars of New Zealand-endemic Leptospira. This method can be used in culture and culture-independent scenarios making it flexible for diagnostics in humans, animals, and environmental samples. We explored the use of this locus as a molecular barcoding tool via the Oxford Nanopore Technology (ONT) sequencing platform MinION. Sequences obtained by this method allowed specific identification of Leptospira species in mixed and enriched environmental cultures, however read error inherent in the MinION sequencing system reduced the accuracy of strain/variant identification. Using this approach to characterise Leptospira in enriched environmental cultures, we detected the likely presence of Leptospira genomospecies that have not been reported in New Zealand to date. This included a strain of L. borgpetersenii that has recently been identified in dairy cattle and sequences similar to those of L. mayottensis. L. tipperaryensis, L. dzianensis and L. alstonii.

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Predicting Current Potential Distribution and the Range Dynamics of Pomacea canaliculata in China under Global Climate Change

Biology ◽

10.3390/biology11010110 ◽

2022 ◽

Vol 11 (1) ◽

pp. 110

Author(s):

Yingxuan Yin ◽

Qing He ◽

Xiaowen Pan ◽

Qiyong Liu ◽

Yinjuan Wu ◽

...

Keyword(s):

Climate Change ◽

Native Species ◽

Potential Distribution ◽

Global Climate ◽

Social Economy ◽

Maximum Temperature ◽

Pomacea Canaliculata ◽

Climate Conditions ◽

Jackknife Test ◽

Recent Climate

Pomacea canaliculata is one of the 100 worst invasive alien species in the world, which has significant effects and harm to native species, ecological environment, human health, and social economy. Climate change is one of the major causes of species range shifts. With recent climate change, the distribution of P. canaliculata has shifted northward. Understanding the potential distribution under current and future climate conditions will aid in the management of the risk of its invasion and spread. Here, we used species distribution modeling (SDM) methods to predict the potential distribution of P. canaliculata in China, and the jackknife test was used to assess the importance of environmental variables for modeling. Our study found that precipitation of the warmest quarter and maximum temperature in the coldest months played important roles in the distribution of P. canaliculata. With global warming, there will be a trend of expansion and northward movement in the future. This study could provide recommendations for the management and prevention of snail invasion and expansion.

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The Effects of Soil Drying Out and Rewetting on Nitrogen and Carbon Leaching—Results of a Long-Term Lysimeter Experiment

Water ◽

10.3390/w13182601 ◽

2021 ◽

Vol 13 (18) ◽

pp. 2601

Author(s):

Holger Rupp ◽

Nadine Tauchnitz ◽

Ralph Meissner

Keyword(s):

Climate Change ◽

Best Management Practices ◽

Management Practices ◽

Global Climate ◽

Significant Risk ◽

Climatic Conditions ◽

Leaching Losses ◽

Lysimeter Experiment ◽

Nitrogen Concentrations ◽

Northeastern Germany

As a result of global climate change, heavy rainfall events and dry periods are increasingly occurring in Germany, with consequences for the water and solute balance of soils to be expected. The effects of climate change on nitrogen and carbon leaching were investigated using 21 non-weighable manually filled lysimeters of the UFZ lysimeter facility Falkenberg, which have been managed since 1991 according to the principles of the best management practices and organic farming. Based on a 29-year dataset (precipitation, evaporation, leachate, nitrate and dissolved organic carbon concentrations), the lysimeter years 1995/96, 2018/19, and 2003/04 were identified as extremely dry years. Under the climatic conditions in northeastern Germany, seepage fluxes were disrupted in these dry years. The reoccurrence of seepage was associated with exceptionally high nitrogen concentrations and leaching losses, which exceeded the current drinking water limits by many times and may result in a significant risk to water quality. In contrast, increased DOC leaching losses occurred primarily as a result of increased seepage fluxes.

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