Pathogens

16 pages, 3961 KiB

Open AccessEditor’s ChoiceArticle

Influence of Different Light Regimes on the Mycoparasitic Activity and 6-Pentyl-α-pyrone Biosynthesis in Two Strains of Trichoderma atroviride

by Dubraska Moreno-Ruiz, Alessandro Fuchs, Kristina Missbach, Rainer Schuhmacher and Susanne Zeilinger

Pathogens 2020, 9(10), 860; https://doi.org/10.3390/pathogens9100860 - 21 Oct 2020

Cited by 15 | Viewed by 3239

Abstract

The ascomycete Trichoderma atroviride is well known for its mycoparasitic lifestyle. Similar to other organisms, light is an important cue for T. atroviride. However, besides triggering of conidiation, little is known on the physiological responses of T. atroviride to light. In this study, [...] Read more.

The ascomycete Trichoderma atroviride is well known for its mycoparasitic lifestyle. Similar to other organisms, light is an important cue for T. atroviride. However, besides triggering of conidiation, little is known on the physiological responses of T. atroviride to light. In this study, we analyzed how cultivation under different light wavelengths and regimes impacted the behavior of two T. atroviride wild-type strains: IMI206040 and P1. While colony extension of both strains was slightly affected by light, massive differences in their photoconidation responses became evident. T. atroviride P1 colonies conidiated under all conditions tested including growth in complete darkness, while IMI206040 required white, blue or green light to trigger asexual reproduction. Interestingly, deletion of the stress-activated MAP kinase-encoding gene tmk3 abolished the ability of strain P1 to conidiate in red and yellow light as well as in darkness. Furthermore, light-dependent differences in the mycoparasitic activity and in the biosynthesis of the secondary metabolite 6-pentyl-α-pyrone (6-PP) became evident. 6-PP production was highest upon dark incubation, while light, especially exposure to white light as light/dark cycles, had an inhibitory effect on its biosynthesis. We conclude that the response of T. atroviride to light is strain-dependent and impacts differentiation, mycoparasitism, and 6-PP production; hence, this should be considered in experiments testing the mycoparasitic activity of these fungi. Full article

(This article belongs to the Section Plant Pathogens)

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13 pages, 1325 KiB

Open AccessArticle

Vector Competence for Dengue-2 Viruses Isolated from Patients with Different Disease Severity

by Ronald Enrique Morales-Vargas, Dorothée Missé, Irwin F. Chavez and Pattamaporn Kittayapong

Pathogens 2020, 9(10), 859; https://doi.org/10.3390/pathogens9100859 - 21 Oct 2020

Cited by 4 | Viewed by 2622

Abstract

Dynamics of dengue serotype 2 virus isolated from patients with different disease severity, namely flu-like classic dengue fever (DF) and dengue shock syndrome (DSS) were studied in its mosquito vector Aedes aegypti. We compared isolate infectivity and vector competence (VC) among thirty [...] Read more.

Dynamics of dengue serotype 2 virus isolated from patients with different disease severity, namely flu-like classic dengue fever (DF) and dengue shock syndrome (DSS) were studied in its mosquito vector Aedes aegypti. We compared isolate infectivity and vector competence (VC) among thirty two A. aegypti-viral isolate pairs. Mosquito populations from high dengue incidence area exhibited overall greater VC than those from low dengue incidence area at 58.1% and 52.5%, respectively. On the other hand, the overall infection rates for the isolates ThNR2/772 (DF, 62.3%) and ThNR2/391 (DSS, 60.9%), were significantly higher than those for isolates ThNR2/406 (DF, 55.2%) and ThNR2/479 (DSS, 54.8%). These results suggest that the efficacy of dengue virus circulation was likely to vary according to the combination between the virus strains and origin of the mosquito strains, and this may have epidemiologic implications toward the incidence of flu-like classic dengue fever (DF) and dengue shock syndrome (DSS). Full article

(This article belongs to the Special Issue Untargeted Alternative Routes of Arbovirus Transmission)

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12 pages, 374 KiB

Open AccessEditor’s ChoiceReview

Control of Cytokines in Latent Cytomegalovirus Infection

by Pearley Chinta, Erica C. Garcia, Kiran Hina Tajuddin, Naomi Akhidenor, Allyson Davis, Lionel Faure and Juliet V. Spencer

Pathogens 2020, 9(10), 858; https://doi.org/10.3390/pathogens9100858 - 21 Oct 2020

Cited by 10 | Viewed by 4091

Abstract

Human cytomegalovirus (HCMV) has evolved a number of mechanisms for long-term co-existence within its host. HCMV infects a wide range of cell types, including fibroblasts, epithelial cells, monocytes, macrophages, dendritic cells, and myeloid progenitor cells. Lytic infection, with the production of infectious progeny [...] Read more.

Human cytomegalovirus (HCMV) has evolved a number of mechanisms for long-term co-existence within its host. HCMV infects a wide range of cell types, including fibroblasts, epithelial cells, monocytes, macrophages, dendritic cells, and myeloid progenitor cells. Lytic infection, with the production of infectious progeny virions, occurs in differentiated cell types, while undifferentiated myeloid precursor cells are the primary site of latent infection. The outcome of HCMV infection depends partly on the cell type and differentiation state but is also influenced by the composition of the immune environment. In this review, we discuss the role of early interactions between HCMV and the host immune system, particularly cytokine and chemokine networks, that facilitate the establishment of lifelong latent infection. A better understanding of these cytokine signaling pathways could lead to novel therapeutic targets that might prevent latency or eradicate latently infected cells. Full article

(This article belongs to the Special Issue Cytomegalovirus (CMV) Infection and Latency)

10 pages, 930 KiB

Open AccessArticle

Molecular and Serological Prevalence of Leptospira spp. in Feral Pigs (Sus scrofa) and their Habitats in Alabama, USA

by Anil Poudel, Md Monirul Hoque, Steven Madere, Sara Bolds, Stuart Price, Subarna Barua, Folasade Adekanmbi, Anwar Kalalah, Steven Kitchens, Vienna Brown, Chengming Wang and B. Graeme Lockaby

Pathogens 2020, 9(10), 857; https://doi.org/10.3390/pathogens9100857 - 20 Oct 2020

Cited by 6 | Viewed by 2838

Abstract

Leptospirosis is a widespread zoonosis and has been recognized as a re-emerging infectious disease in humans and a variety of wild and domestic animal species. In order to understand the prevalence and diversity of Leptospira spp. in feral pig populations of Alabama, we [...] Read more.

Leptospirosis is a widespread zoonosis and has been recognized as a re-emerging infectious disease in humans and a variety of wild and domestic animal species. In order to understand the prevalence and diversity of Leptospira spp. in feral pig populations of Alabama, we trapped 315 feral pigs in Bullock County east-central Alabama, and collected 97 environmental samples from riparian areas in Bullock County and Macon County east-central Alabama. Two previously published PCRs followed by DNA sequencing and BLASTn were performed to identify pathogenic Leptospira species in the kidney of feral pigs (3.2%, 10/315) as well as environmental samples collected from the habitats of feral pigs (2.1%, 2/97), but not in the whole blood samples (n = 276) or spleen (n = 51). An ELISA determined that 44.2% of serum samples (122/276) were antibody-positive for Leptospira. The identification of two pathogenic Leptospira species from environmental samples and the high sero-positivity in feral pigs suggests potential pathogen shedding from feral pigs to environments, and to humans and domestic animals. In order to better understand the risk to human health associated with feral swine presence, further studies are warranted to explore the interrelationship between Leptospira spp. shedding in the urine of feral pigs and bacterial culture to explore pathogenicity. Multi-locus sequencing typing (MLST) and microscopic agglutination tests (MAT) should be performed in future studies to make a definite determination of pathogenic Leptospira in feral pigs in Alabama. Full article

(This article belongs to the Section Animal Pathogens)

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21 pages, 984 KiB

Open AccessEditor’s ChoiceReview

Hepatitis E Virus Infection: Circulation, Molecular Epidemiology, and Impact on Global Health

by Srinivas Reddy Pallerla, Dominik Harms, Reimar Johne, Daniel Todt, Eike Steinmann, Mathias Schemmerer, Jürgen J. Wenzel, Jörg Hofmann, James Wai Kuo Shih, Heiner Wedemeyer, C.-Thomas Bock and Thirumalaisamy P. Velavan

Pathogens 2020, 9(10), 856; https://doi.org/10.3390/pathogens9100856 - 20 Oct 2020

Cited by 69 | Viewed by 7309

Abstract

Infection with hepatitis E virus (HEV) represents the most common source of viral hepatitis globally. Although infecting over 20 million people annually in endemic regions, with major outbreaks described since the 1950s, hepatitis E remains an underestimated disease. This review gives a current [...] Read more.

Infection with hepatitis E virus (HEV) represents the most common source of viral hepatitis globally. Although infecting over 20 million people annually in endemic regions, with major outbreaks described since the 1950s, hepatitis E remains an underestimated disease. This review gives a current view of the global circulation and epidemiology of this emerging virus. The history of HEV, from the first reported enteric non-A non-B hepatitis outbreaks, to the discovery of the viral agent and the molecular characterization of the different human pathogenic genotypes, is discussed. Furthermore, the current state of research regarding the virology of HEV is critically assessed, and the challenges towards prevention and diagnosis, as well as clinical risks of the disease described. Together, these points aim to underline the significant impact of hepatitis E on global health and the need for further in-depth research to better understand the pathophysiology and its role in the complex disease manifestations of HEV infection. Full article

(This article belongs to the Special Issue Hepatitis E Virus (HEV) Infections)

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14 pages, 3237 KiB

Open AccessArticle

Ursolic Acid Potentializes Conventional Therapy in Experimental Leishmaniasis

by Jéssica Adriana Jesus, Thays Nicolli Fragoso da Silva, Eduardo Seiji Yamamoto, João Henrique G. Lago, Márcia Dalastra Laurenti and Luiz Felipe Domingues Passero

Pathogens 2020, 9(10), 855; https://doi.org/10.3390/pathogens9100855 - 20 Oct 2020

Cited by 10 | Viewed by 2777

Abstract

Ursolic acid (UA) is a triterpene with a broad array of pharmacological activities. In leishmaniasis, UA killed different species of parasites, and it was active in the experimental model of cutaneous and visceral leishmaniasis. Thus, the objective of this work was to study [...] Read more.

Ursolic acid (UA) is a triterpene with a broad array of pharmacological activities. In leishmaniasis, UA killed different species of parasites, and it was active in the experimental model of cutaneous and visceral leishmaniasis. Thus, the objective of this work was to study the therapeutic efficacy of the conventional drugs amphotericin B (AmB) or glucantime (Glu) combined with UA in experimental visceral and cutaneous leishmaniasis, respectively. L. (L.) infantum-infected hamsters were treated with AmB alone or combined with UA. L. (L.) amazonensis-infected BALB/c mice were treated with Glu alone or combined with UA. Animals were treated for 15 consecutive days by intraperitoneal or intralesional routes. Following one week after the last dose, the tissue parasitism and cellular immune responses were analyzed. Hamsters treated with 0.2 and 1.0 mg/kg of AmB plus 1.0 mg/kg of UA showed low hepatic and splenic parasitisms; however, AmB given as monotherapy did not reduce the number of viable parasites in the spleen of treated animals. In cutaneous leishmaniasis, Glu given as monotherapy was inactive at 2.0 mg/kg, showed mild activity at 10.0 mg/kg, and at 50.0 mg/kg was highly active at eliminating parasites in the skin. When animals were treated with Glu plus UA, higher leishmanicidal activity was observed in comparison to all groups treated with monotherapy schemes, and such activity was related to lesion improvement and upregulation of IFN-γ production. Altogether, data suggest that the association of drugs for the treatment of leishmaniasis can increase the efficiency of the treatment and decrease the toxicity associated to the conventional drugs. Full article

(This article belongs to the Section Vaccines and Therapeutic Developments)

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14 pages, 2679 KiB

Open AccessEditor’s ChoiceArticle

Prevalence of Cytauxzoon felis Infection-Carriers in Eastern Kansas Domestic Cats

by Yvonne M. Wikander, Tippawan Anantatat, Qing Kang and Kathryn E. Reif

Pathogens 2020, 9(10), 854; https://doi.org/10.3390/pathogens9100854 - 20 Oct 2020

Cited by 10 | Viewed by 4902

Abstract

Cytauxzoon felis is a hemoprotozoal tick-transmitted pathogen of felids. Felids that survive acute disease often remain infected and serve as reservoirs for subsequent tick transmission to other susceptible felines. States adjacent to Kansas have identified C. felis-domestic cat carriers while statewide awareness [...] Read more.

Cytauxzoon felis is a hemoprotozoal tick-transmitted pathogen of felids. Felids that survive acute disease often remain infected and serve as reservoirs for subsequent tick transmission to other susceptible felines. States adjacent to Kansas have identified C. felis-domestic cat carriers while statewide awareness and concern of cytauxzoonosis have increased. The objective of this study was to determine the prevalence of C. felis-carriers in the eastern Kansas domestic cat population using a sensitive quantitative PCR assay targeting the C. felis Cox3 mitochondrial gene. An overall C. felis infection prevalence of 25.8% was determined for asymptomatic domestic cats in eastern Kansas. Significantly more C. felis-carrier cats were identified in spring and fall, suggesting a seasonal fluctuation of survivors. Additionally, a greater percentage of feral and owned cats were positive for C. felis compared to rescue/rescinded cats. This study demonstrates that C. felis-domestic cat carriers are common among cats that spend at least a portion of time outdoors in eastern Kansas, and that more cats likely survive cytauxzoonosis than expected. Understanding the role of domestic cat carriers of C. felis is essential in developing cytauxzoonosis mitigation strategies, including recommending year-round use of acaricide products for all cats that spend any time outdoors. Full article

(This article belongs to the Section Animal Pathogens)

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11 pages, 400 KiB

Open AccessArticle

An Abattoir-Based Study on the Prevalence of Salmonella Fecal Carriage and ESBL Related Antimicrobial Resistance from Culled Adult Dairy Cows in Wuhan, China

by Jie Wang, Kaili Xue, Ping Yi, Xiaojie Zhu, Qingjie Peng, Zijian Wang, Yongchong Peng, Yingyu Chen, Ian D. Robertson, Xiang Li, Aizhen Guo and Joshua W. Aleri

Pathogens 2020, 9(10), 853; https://doi.org/10.3390/pathogens9100853 - 19 Oct 2020

Cited by 7 | Viewed by 2879

Abstract

The objective of this study was to estimate the fecal carriage of Salmonella spp. among culled adult dairy cows presented to an abattoir in Wuhan, China and to evaluate their antimicrobial resistance profiles. Rectal swabs from 138 culled cows were cultured. Laboratory analysis [...] Read more.

The objective of this study was to estimate the fecal carriage of Salmonella spp. among culled adult dairy cows presented to an abattoir in Wuhan, China and to evaluate their antimicrobial resistance profiles. Rectal swabs from 138 culled cows were cultured. Laboratory analysis involved the identification of Salmonella, the susceptibility assessment and the presence of Extended Spectrum β-lactamases and mcr genes in the isolates. An overall prevalence of Salmonella of 29.0% was recorded with 63.4% (26/41) and 2.4% (1/41) of the isolates identified as S. Typhimurium and S. Dublin, respectively. The occurrence of Salmonella was higher (odd ratios: 3.3) in culled cows originating from the northeast zone of China than cows originating from the central and north zones. Twenty multi-drug resistant strains (resistant to three or more antimicrobial agents) were detected (48.8%) and overall, a high resistance to ampicillin (36/41) and tetracycline (15/41) was observed. Extended Spectrum β-lactamases phenotypes were found in 7/41 isolates, of which all contained the bla_CTX-M resistance gene, and no mcr genes were found by polymerase chain reaction. The high prevalence of Salmonella fecal carriage and antimicrobial resistance may contribute to an increased risk of Salmonella transmission to food. Full article

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15 pages, 2692 KiB

Open AccessArticle

Concordance between Histology, Immunohistochemistry, and RT-PCR in the Diagnosis of Feline Infectious Peritonitis

by Angelica Stranieri, Donatella Scavone, Saverio Paltrinieri, Alessia Giordano, Federico Bonsembiante, Silvia Ferro, Maria Elena Gelain, Sara Meazzi and Stefania Lauzi

Pathogens 2020, 9(10), 852; https://doi.org/10.3390/pathogens9100852 - 18 Oct 2020

Cited by 14 | Viewed by 6713

Abstract

Histology, immunohistochemistry (IHC), and reverse transcription polymerase chain reaction (RT-PCR) have been used to diagnose feline infectious peritonitis (FIP), but no information regarding the comparison of their diagnostic performances on the same organ is available. The aims of this study were to determine [...] Read more.

Histology, immunohistochemistry (IHC), and reverse transcription polymerase chain reaction (RT-PCR) have been used to diagnose feline infectious peritonitis (FIP), but no information regarding the comparison of their diagnostic performances on the same organ is available. The aims of this study were to determine the concordance among these tests and to evaluate which combination of tests and organs can be used in vivo. Histology, IHC, and nested RT-PCR (RT-nPCR) for feline coronavirus (FCoV) were performed on spleen, liver, mesenteric lymph node, kidney, large and small intestine, and lung from 14 FIP and 12 non-FIP cats. Sensitivity, specificity, predictive values, likelihood ratios, and concordance were calculated. IHC and RT-nPCR had the highest concordance in lung and liver, histology and IHC in the other organs. The sensitivity of histology, IHC, and RT-nPCR on the different organs ranged from 41.7 to 76.9%, 46.2 to 76.9%, and 64.3 to 85.7%, respectively, and their specificity ranged from 83.3 to 100.0%, 100% and 83.3 to 100.0%. Therefore, IHC is recommended when histology is consistent with FIP. If RT-nPCR is performed as the first diagnostic approach, results should always be confirmed with IHC. Lung or liver provide accurate information regardless of the method, while IHC is preferred to RT-nPCR to confirm FIP in the kidney or intestine. Full article

(This article belongs to the Special Issue Advances on Feline Coronavirus Infection)

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8 pages, 1279 KiB

Open AccessArticle

Onychomycosis in Northwestern Greece over a 7-Year Period

by Hercules Sakkas, Christos Kittas, Georgia Kapnisi, Efthalia Priavali, Amalia Kallinteri, Ioannis D. Bassukas and Konstantina Gartzonika

Pathogens 2020, 9(10), 851; https://doi.org/10.3390/pathogens9100851 - 17 Oct 2020

Cited by 13 | Viewed by 2912

Abstract

Onychomycosis is considered as one of the major public health problems with a global distribution associated with geographic, demographic and environmental factors, underlying comorbidities and immunodeficiency disorders. This study was conducted to investigate the etiological agents of onychomycosis, in Northwestern Greece during a [...] Read more.

Onychomycosis is considered as one of the major public health problems with a global distribution associated with geographic, demographic and environmental factors, underlying comorbidities and immunodeficiency disorders. This study was conducted to investigate the etiological agents of onychomycosis, in Northwestern Greece during a 7-year period. The study population included 1095 outpatients with clinically suspected onychomycosis that presented to the University Hospital of Ioannina, NW Greece (2011–2017). Samples were examined for causative fungi, and mycological identification was established using standard mycological methods. Demographic data of each patient, comorbidities, localization of infection and history of previous fungal infection were collected. Onychomycosis was diagnosed in 317 of the 1095 suspected cases (28.9%) and the most frequently isolated pathogens were yeasts (50.8%) followed by dermatophytes (36.9%) and non-dermatophyte molds (NDMs) (12.3%). Dermatophytes were mostly involved in toenail onychomycosis (90.6%) and more commonly affected males than females (57.3% vs. 42.7%), while the predominantly isolated pathogen was Τrichophyton rubrum (74.4%) followed by Τrichophyton interdigitale (21.4%). Candida albicans was the most prevalent isolated yeast (82%), whereas among the cases with onychomycosis due to NDMs, Aspergillus spp. were isolated as the principal species (59%). Continuous monitoring should be performed in order to identify possible trends and shifts in species isolation rates and to evaluate the impact of onychomycosis among the general population and high-risk groups. Full article

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29 pages, 1543 KiB

Open AccessEditor’s ChoiceReview

Immunological Perspective for Ebola Virus Infection and Various Treatment Measures Taken to Fight the Disease

by Sahil Jain, Svetlana F. Khaiboullina and Manoj Baranwal

Pathogens 2020, 9(10), 850; https://doi.org/10.3390/pathogens9100850 - 17 Oct 2020

Cited by 18 | Viewed by 6142

Abstract

Ebolaviruses, discovered in 1976, belongs to the Filoviridae family, which also includes Marburg and Lloviu viruses. They are negative-stranded RNA viruses with six known species identified to date. Ebola virus (EBOV) is a member of Zaire ebolavirus species and can cause the Ebola [...] Read more.

Ebolaviruses, discovered in 1976, belongs to the Filoviridae family, which also includes Marburg and Lloviu viruses. They are negative-stranded RNA viruses with six known species identified to date. Ebola virus (EBOV) is a member of Zaire ebolavirus species and can cause the Ebola virus disease (EVD), an emerging zoonotic disease that results in homeostatic imbalance and multi-organ failure. There are three EBOV outbreaks documented in the last six years resulting in significant morbidity (>32,000 cases) and mortality (>13,500 deaths). The potential factors contributing to the high infectivity of this virus include multiple entry mechanisms, susceptibility of the host cells, employment of multiple immune evasion mechanisms and rapid person-to-person transmission. EBOV infection leads to cytokine storm, disseminated intravascular coagulation, host T cell apoptosis as well as cell mediated and humoral immune response. In this review, a concise recap of cell types targeted by EBOV and EVD symptoms followed by detailed run-through of host innate and adaptive immune responses, virus-driven regulation and their combined effects contributing to the disease pathogenesis has been presented. At last, the vaccine and drug development initiatives as well as challenges related to the management of infection have been discussed. Full article

(This article belongs to the Special Issue Pathogenesis of Emerging Zoonotic Viral Infections)

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13 pages, 1154 KiB

Open AccessArticle

Inactivation of Multi-Drug Resistant Non-Typhoidal Salmonella and Wild-Type Escherichia coli STEC Using Organic Acids: A Potential Alternative to the Food Industry

by Vinicius Silva Castro, Yhan da Silva Mutz, Denes Kaic Alves Rosario, Adelino Cunha-Neto, Eduardo Eustáquio de Souza Figueiredo and Carlos Adam Conte-Junior

Pathogens 2020, 9(10), 849; https://doi.org/10.3390/pathogens9100849 - 16 Oct 2020

Cited by 13 | Viewed by 2865

Abstract

Salmonella and Escherichia coli are the main bacterial species involved in food outbreaks worldwide. Recent reports showed that chemical sanitizers commonly used to control these pathogens could induce antibiotic resistance. Therefore, this study aimed to describe the efficiency of chemical sanitizers and organic [...] Read more.

Salmonella and Escherichia coli are the main bacterial species involved in food outbreaks worldwide. Recent reports showed that chemical sanitizers commonly used to control these pathogens could induce antibiotic resistance. Therefore, this study aimed to describe the efficiency of chemical sanitizers and organic acids when inactivating wild and clinical strains of Salmonella and E. coli, targeting a 4-log reduction. To achieve this goal, three methods were applied. (i) Disk-diffusion challenge for organic acids. (ii) Determination of MIC for two acids (acetic and lactic), as well as two sanitizers (quaternary compound and sodium hypochlorite). (iii) The development of inactivation models from the previously defined concentrations. In disk-diffusion, the results indicated that wild strains have higher resistance potential when compared to clinical strains. Regarding the models, quaternary ammonium and lactic acid showed a linear pattern of inactivation, while sodium hypochlorite had a linear pattern with tail dispersion, and acetic acid has Weibull dispersion to E. coli. The concentration to 4-log reduction differed from Salmonella and E. coli in acetic acid and sodium hypochlorite. The use of organic acids is an alternative method for antimicrobial control. Our study indicates the levels of organic acids and sanitizers to be used in the inactivation of emerging foodborne pathogens. Full article

(This article belongs to the Section Waterborne/Foodborne/Airborne Pathogens)

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17 pages, 1938 KiB

Open AccessEditor’s ChoiceArticle

Sequencing of Historical Isolates, K-mer Mining and High Serological Cross-Reactivity with Ross River Virus Argue against the Presence of Getah Virus in Australia

by Daniel J. Rawle, Wilson Nguyen, Troy Dumenil, Rhys Parry, David Warrilow, Bing Tang, Thuy T. Le, Andrii Slonchak, Alexander A. Khromykh, Viviana P. Lutzky, Kexin Yan and Andreas Suhrbier

Pathogens 2020, 9(10), 848; https://doi.org/10.3390/pathogens9100848 - 16 Oct 2020

Cited by 14 | Viewed by 4329

Abstract

Getah virus (GETV) is a mosquito-transmitted alphavirus primarily associated with disease in horses and pigs in Asia. GETV was also reported to have been isolated from mosquitoes in Australia in 1961; however, retrieval and sequencing of the original isolates (N544 and N554), illustrated [...] Read more.

Getah virus (GETV) is a mosquito-transmitted alphavirus primarily associated with disease in horses and pigs in Asia. GETV was also reported to have been isolated from mosquitoes in Australia in 1961; however, retrieval and sequencing of the original isolates (N544 and N554), illustrated that these viruses were virtually identical to the 1955 GETV_MM2021 isolate from Malaysia. K-mer mining of the >40,000 terabases of sequence data in the Sequence Read Archive followed by BLASTn confirmation identified multiple GETV sequences in biosamples from Asia (often as contaminants), but not in biosamples from Australia. In contrast, sequence reads aligning to the Australian Ross River virus (RRV) were readily identified in Australian biosamples. To explore the serological relationship between GETV and other alphaviruses, an adult wild-type mouse model of GETV was established. High levels of cross-reactivity and cross-protection were evident for convalescent sera from mice infected with GETV or RRV, highlighting the difficulties associated with the interpretation of early serosurveys reporting GETV antibodies in Australian cattle and pigs. The evidence that GETV circulates in Australia is thus not compelling. Full article

(This article belongs to the Special Issue Animal Vector-Borne Diseases)

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7 pages, 586 KiB

Open AccessArticle

OV16 Seroprevalence among Persons with Epilepsy in Onchocerciasis Endemic Regions: A Multi-Country Study

by Alfred Dusabimana, Dan Bhwana, Michel Mandro, Bruno P. Mmbando, Joseph N. Siewe Fodjo and Robert Colebunders

Pathogens 2020, 9(10), 847; https://doi.org/10.3390/pathogens9100847 - 16 Oct 2020

Cited by 3 | Viewed by 2647

Abstract

There is growing epidemiological evidence that onchocerciasis may induce epilepsy. High prevalence of onchocerciasis has been reported in onchocerciasis-meso and hyper-endemic regions. We aimed to determine the OV16 antibody prevalence in persons with epilepsy (PWE) in four onchocerciasis-endemic regions. PWE were identified during [...] Read more.

There is growing epidemiological evidence that onchocerciasis may induce epilepsy. High prevalence of onchocerciasis has been reported in onchocerciasis-meso and hyper-endemic regions. We aimed to determine the OV16 antibody prevalence in persons with epilepsy (PWE) in four onchocerciasis-endemic regions. PWE were identified during studies in Mahenge area (Tanzania), Kitgum and Pader districts (Uganda), the Mbam and Sanaga river valleys (Cameroon), and the Logo health zone (Democratic Republic of Congo). Exposure to Onchocerca volvulus was assessed by testing PWE for OV16 IgG4 antibodies using a rapid diagnostic test. The OV16 seroprevalence among PWE in the four onchocerciasis-endemic study sites ranged from 35.2% to 59.7%. OV16 seroprevalence increased with age until the age of 39 years, after which it decreased drastically. Our study suggests that, in onchocerciasis-endemic regions, epilepsy in young people is often associated with onchocerciasis, while epilepsy in older persons seems unrelated to O. volvulus exposure. Full article

(This article belongs to the Section Human Pathogens)

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17 pages, 1968 KiB

Open AccessArticle

Detection of Borrelia burgdorferi Sensu Lato and Relapsing Fever Borrelia in Feeding Ixodes Ticks and Rodents in Sarawak, Malaysia: New Geographical Records of Borrelia yangtzensis and Borrelia miyamotoi

by Alice C. C. Lau, Yongjin Qiu, Mohamed Abdallah Mohamed Moustafa, Ryo Nakao, Michito Shimozuru, Manabu Onuma, Jayasilan Mohd-Azlan and Toshio Tsubota

Pathogens 2020, 9(10), 846; https://doi.org/10.3390/pathogens9100846 - 15 Oct 2020

Cited by 14 | Viewed by 4932

Abstract

Members of the Borrelia burgdorferi sensu lato (Bbsl) complex are etiological agents of Lyme disease (LD), and Borrelia miyamotoi is one of the relapsing fever Borrelia (RFB). Despite the serological evidence of LD in Malaysia, there has been no report from Sarawak, Malaysian [...] Read more.

Members of the Borrelia burgdorferi sensu lato (Bbsl) complex are etiological agents of Lyme disease (LD), and Borrelia miyamotoi is one of the relapsing fever Borrelia (RFB). Despite the serological evidence of LD in Malaysia, there has been no report from Sarawak, Malaysian Borneo. Thus, this study aimed to detect and characterize Borrelia in rodents and Ixodes ticks from primary forests and an oil palm (OP) plantation in Sarawak. Borrelia yangtzensis (a member of the Bbsl complex) was detected in 43.8% (14/32) of Ixodes granulatus; most of the positive ticks were from the OP plantation (13/14). Out of 56 rodents, B. yangtzensis was detected in four Rattus spp. from the OP plantation and B. miyamotoi was detected in one rodent, Sundamys muelleri, from the primary forest. Further, the positive samples of B. yangtzensis were randomly selected for multilocus sequence analysis (MLSA). The MLSA results of successfully amplified tick samples revealed a clustering with the sequences isolated from Japan and China. This study is the first evidence of B. miyamotoi, a known human pathogen in Malaysia, and B. yangtzensis, which is circulating in ticks and rodents in Sarawak, Malaysian Borneo, and presenting a new geographical record of the Borrelia spp. Full article

(This article belongs to the Section Human Pathogens)

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19 pages, 1660 KiB

Open AccessEditor’s ChoiceReview

Renibacterium salmoninarum—The Causative Agent of Bacterial Kidney Disease in Salmonid Fish

by Mohammad Reza Delghandi, Mansour El-Matbouli and Simon Menanteau-Ledouble

Pathogens 2020, 9(10), 845; https://doi.org/10.3390/pathogens9100845 - 15 Oct 2020

Cited by 26 | Viewed by 7983

Abstract

Renibacterium salmoninarum is one of the oldest known bacterial pathogens of fish. This Gram-positive bacterium is the causative agent of bacterial kidney disease, a chronic infection that is mostly known to infect salmonid fish at low temperatures. Externally, infected fish can display exophthalmia [...] Read more.

Renibacterium salmoninarum is one of the oldest known bacterial pathogens of fish. This Gram-positive bacterium is the causative agent of bacterial kidney disease, a chronic infection that is mostly known to infect salmonid fish at low temperatures. Externally, infected fish can display exophthalmia as well as blebs on the skin and ulcerations alongside haemorrhages at the base of the fins and alongside the lateral line. Internally, the kidney, heart, spleen and liver can show signs of swelling. Granulomas can be seen on various internal organs, as can haemorrhages, and the organs can be covered with a false membrane. Ascites can also accumulate in the abdominal cavity. The bacterium is generally cultivated on specialized media such as kidney disease medium-1 (KDM-1), KDM-2 and selective kidney disease medium (SKDM), and a diagnostic is performed using molecular tools such as PCRs or real-time quantitative PCRs (RT-qPCRs). Several virulence mechanisms have been identified in R. salmoninarum, in particular the protein p57 that is known to play a role in both agglutination and immunosuppression of the host’s defense mechanisms. Control of the disease is difficult; the presence of asymptomatic carriers complicates the eradication of the disease, as does the ability of the bacterium to gain entrance inside the eggs. Bacterin-killed vaccines have proven to be of doubtful efficacy in controlling the disease, and even more recent application of a virulent environmental relative of R. salmoninarum is of limited efficacy. Treatment by antibiotics such as erythromycin, azithromycin and enrofloxacin can be effective but it is slow and requires prolonged treatment. Moreover, antibiotic-resistant strains have been reported. Despite being known for a long time, there is still much to be discovered about R. salmoninarum, notably regarding its virulence mechanisms and its vaccine potential. Consequently, these gaps in knowledge continue to hinder control of this bacterial disease in aquaculture settings. Full article

(This article belongs to the Special Issue Pathogen Characterization, Host Immune Response and Development of Strategies to Reduce Losses to Disease in Aquaculture)

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9 pages, 271 KiB

Open AccessReview

Sepsis, Phages, and COVID-19

by Andrzej Górski, Jan Borysowski and Ryszard Międzybrodzki

Pathogens 2020, 9(10), 844; https://doi.org/10.3390/pathogens9100844 - 15 Oct 2020

Cited by 8 | Viewed by 4086

Abstract

Phage therapy has emerged as a potential novel treatment of sepsis for which no decisive progress has been achieved thus far. Obviously, phages can help eradicate local bacterial infection and bacteremia that may occur in a syndrome. For example, phages may be helpful [...] Read more.

Phage therapy has emerged as a potential novel treatment of sepsis for which no decisive progress has been achieved thus far. Obviously, phages can help eradicate local bacterial infection and bacteremia that may occur in a syndrome. For example, phages may be helpful in correcting excessive inflammatory responses and aberrant immunity that occur in sepsis. Data from animal studies strongly suggest that phages may indeed be an efficient means of therapy for experimentally induced sepsis. In recent years, a number of reports have appeared describing the successful treatment of patients with sepsis. Moreover, novel data on the anti-viral potential of phages may be interpreted as suggesting that phages could be used as an adjunct therapy in severe COVID-19. Thus, clinical trials assessing the value of phage therapy in sepsis, including viral sepsis, are urgently needed. Full article

(This article belongs to the Section Viral Pathogens)

18 pages, 2034 KiB

Open AccessArticle

Immune Modulation and the Development of Fowl Typhoid: A Model of Human Disease?

by Ying Tang, Michael Jones, Paul A. Barrow and Neil Foster

Pathogens 2020, 9(10), 843; https://doi.org/10.3390/pathogens9100843 - 15 Oct 2020

Cited by 4 | Viewed by 3075

Abstract

Salmonella enterica serovar Gallinarum (S. Gallinarum) is the cause of typhoid in chickens but the immune factors that may facilitate the development of typhoid have not been fully elucidated. We show that, in contrast to non-typhoid S. Enteritidis infection, S [...] Read more.

Salmonella enterica serovar Gallinarum (S. Gallinarum) is the cause of typhoid in chickens but the immune factors that may facilitate the development of typhoid have not been fully elucidated. We show that, in contrast to non-typhoid S. Enteritidis infection, S. Gallinarum significantly reduced nitrite ion production and expression of mRNA for heterophil granulocyte chemoattractants CXCLi2 and IL-6 in chicken monocyte-derived macrophages (chMDMs) (p < 0.05) at 6 h post-infection (pi). S. Gallinarum also reduced IFN-γ and IL-17 expression by CD4⁺ lymphocytes cultured with infected chMDMs for 5 days but did not induce a Th2 phenotype or anergy. In vivo, S. Gallinarum also induced significantly lower expression of CXCLi1, CXCLi2, IL-1β, IL-6 and iNOS mRNA in the caecal tonsil by day 2 pi (p < 0.05–0.01) and consistently lower levels of IFN-γ, IL-18, IL-12, and IL-17. In the spleen, S. Gallinarum induced significantly lower levels of iNOS and IFN-γ (p < 0.01 and 0.05 respectively) and consistently lower levels of IL-18 and IL-12 but significantly greater (p < 0.01) expression of anti-inflammatory IL-10 at day 4 and 5 pi when compared to S. Enteritidis. This immune phenotype was associated with transit from the intestinal tissues to the liver by S. Gallinarum, not observed following S. Enteritidis infection. In conclusion, we report an immune mechanism that may facilitate typhoid disease in S. Gallinarum-infected chickens. However, down-regulation of inflammatory mediators, upregulation of IL-10, and associated liver colonisation are also characteristic of human typhoid, suggesting that this may also be a useful model of typhoid in humans. Full article

(This article belongs to the Special Issue Reviews From Section "Animal Pathogens")

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11 pages, 2420 KiB

Open AccessArticle

Establishment of an In Vitro Model of Persistent Chicken Anemia Virus Infection

by Hieu Van Dong, Giang Thi Huong Tran, Dai Quang Trinh, Yohei Takeda, Haruko Ogawa and Kunitoshi Imai

Pathogens 2020, 9(10), 842; https://doi.org/10.3390/pathogens9100842 - 15 Oct 2020

Cited by 2 | Viewed by 3329

Abstract

Persistent infection of chicken anemia virus (CAV) in chickens has been suspected to result in immunosuppression and exogenous virus contamination within vaccine production. However, no direct evidence for persistent CAV infection has thus far been obtained. In this study, we aimed to establish [...] Read more.

Persistent infection of chicken anemia virus (CAV) in chickens has been suspected to result in immunosuppression and exogenous virus contamination within vaccine production. However, no direct evidence for persistent CAV infection has thus far been obtained. In this study, we aimed to establish an in vitro model of persistent CAV infection. CAV-infected MDCC-MSB1 (MSB1) cells, a Marek’s disease virus-transformed continuous cell line, were cultured in the presence of both CAV and CAV neutralizing antibody (NA). Cell viability, expression of viral antigens, viral DNA, and recovery of CAV were examined by acridine orange/propidium iodide staining, immunofluorescence measurement, real-time PCR, and viral isolation, respectively. The results indicated that CAV was maintained and possibly replicated in CAV-infected cells cultured in the presence of NA, without affecting host cell viability. It was also shown that persistently infectious CAV induced cell death again after removing NA. The persistent infection of CAV in MSB1 cells was not related to viral gene mutation. In summary, we have herein established a novel model of persistent CAV infection in MSB1 cells cultured in the presence of NA. Full article

(This article belongs to the Special Issue Chicken Anaemia Virus Infection)

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16 pages, 2161 KiB

Open AccessArticle

Diverse Epidemiology of Leptospira Serovars Notified in New Zealand, 1999–2017

by Shahista Nisa, David A. Wilkinson, Olivia Angelin-Bonnet, Shevaun Paine, Karen Cullen, Jackie Wright, Michael G. Baker and Jackie Benschop

Pathogens 2020, 9(10), 841; https://doi.org/10.3390/pathogens9100841 - 14 Oct 2020

Cited by 16 | Viewed by 4549

Abstract

Leptospirosis in New Zealand has been strongly associated with animal-contact occupations and with serovars Hardjo and Pomona. However, recent data suggest changes in these patterns, hence, serovar-specific epidemiology of leptospirosis from 1999 to 2017 was investigated. The 19-year average annual incidence is 2.01/100,000. [...] Read more.

Leptospirosis in New Zealand has been strongly associated with animal-contact occupations and with serovars Hardjo and Pomona. However, recent data suggest changes in these patterns, hence, serovar-specific epidemiology of leptospirosis from 1999 to 2017 was investigated. The 19-year average annual incidence is 2.01/100,000. Early (1999–2007) and late (2008–2017) study period comparisons showed a significant increase in notifications with serovar Ballum (IRR: 1.59, 95% CI: 1.22–2.09) in all cases and serovar Tarassovi (IRR: 1.75, 95% CI: 1.13–2.78) in Europeans and a decrease in notifications with serovars Hardjo and Pomona in all cases. Incidences of Ballum peaked in winter, Hardjo peaked in spring and Tarassovi peaked in summer. Incidence was highest in Māori (2.24/100,000) with dominant serovars being Hardjo and Pomona. Stratification by occupation showed meat workers had the highest incidence of Hardjo (57.29/100,000) and Pomona (45.32/100,000), farmers had the highest incidence of Ballum (11.09/100,000) and dairy farmers had the highest incidence of Tarassovi (12.59/100,000). Spatial analysis showed predominance of Hardjo and Pomona in Hawke’s Bay, Ballum in West Coast and Northland and Tarassovi in Waikato, Taranaki and Northland. This study highlights the serovar-specific heterogeneity of human leptospirosis in New Zealand that should be considered when developing control and prevention strategies. Full article

(This article belongs to the Special Issue A Disease with Dual Impacts: Leptospirosis in Humans and Livestock)

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18 pages, 458 KiB

Open AccessArticle

Precarity at the Margins of Malaria Control in the Chittagong Hill Tracts in Bangladesh: A Mixed-Methods Study

by Mohammad Abdul Matin, Nandini D. P. Sarkar, Ching Swe Phru, Benedikt Ley, Kamala Thriemer, Ric N. Price, Koen Peeters Grietens, Wasif Ali Khan, Mohammad Shafiul Alam and Charlotte Gryseels

Pathogens 2020, 9(10), 840; https://doi.org/10.3390/pathogens9100840 - 14 Oct 2020

Cited by 7 | Viewed by 3557

Abstract

Bangladesh has achieved significant progress towards malaria elimination, although health service delivery for malaria remains challenging in remote forested areas such as the Chittagong Hill Tracts (CHT). The aim of this study was to investigate perceptions of malaria and its treatment among the [...] Read more.

Bangladesh has achieved significant progress towards malaria elimination, although health service delivery for malaria remains challenging in remote forested areas such as the Chittagong Hill Tracts (CHT). The aim of this study was to investigate perceptions of malaria and its treatment among the local population to inform contextualized strategies for rolling out radical cure for P. vivax in Bangladesh. The study comprised two sequential strands whereby the preliminary results of a qualitative strand informed the development of a structured survey questionnaire used in the quantitative strand. Results show that ethnic minority populations in the CHT live in precarious socio-economic conditions which increase their exposure to infectious diseases, and that febrile patients often self-treat, including home remedies and pharmaceuticals, before attending a healthcare facility. Perceived low quality of care and lack of communication between Bengali health providers and ethnic minority patients also affects access to public healthcare. Malaria is viewed as a condition that affects vulnerable people weakened by agricultural work and taking away blood is perceived to increase such vulnerability. Healthcare providers that initiate and sustain a dialogue about these issues with ethnic minority patients may foster the trust that is needed for local malaria elimination efforts. Full article

(This article belongs to the Special Issue Addressing Plasmodium vivax: From Control to Elimination)

17 pages, 1914 KiB

Open AccessArticle

Porcine Circovirus Type 2 Pathogenicity Alters Host’s Central Tolerance for Propagation

by Xaver Sidler, Titus Sydler, José Maria Mateos, Stefanie Klausmann and Enrico Brugnera

Pathogens 2020, 9(10), 839; https://doi.org/10.3390/pathogens9100839 - 13 Oct 2020

Cited by 3 | Viewed by 2705

Abstract

Porcine circovirus type 2 (PCV2) infections and resulting diseases are a worldwide threat to pig production. PCV2 bears a uniqueness that allows for us to understand more about chronic infections and the immune system in general. The virus can be phylogenetically subdivided into [...] Read more.

Porcine circovirus type 2 (PCV2) infections and resulting diseases are a worldwide threat to pig production. PCV2 bears a uniqueness that allows for us to understand more about chronic infections and the immune system in general. The virus can be phylogenetically subdivided into PCV2a to PCV2h genotypes. Although vaccination against PCV2 has been seen to prevent the manifestation of PCV disease, PCV2 still lingers as subclinical infections in all developmental stages of pigs. The “slow and low” tactic gives PCV2 a particular advantage in a host’s immune surveillance. Since the inception of the PCV2 associated panzootic, research scientists have been trying to understand the pathogenicity of PCV2. Different research groups found that one genotype group member was more pathogenic than others. We found, in our weaner infection model with in vivo transfection of different recombinant PCV2 genotype group members that these viruses alter T cell maturation in the thymus, including host’s central tolerance. Here, we extend these original observations by showing that PCV2 infected cells were also found in proximity within the female and male reproductive organs of stillborn pig fetuses. These PCV2 pools were sufficient in infecting three and half-day-old embryos in sows. Furthermore, the dominant PCV2 group member was more pathogenic in our weaner infection model. PCV2 pre-immunocompetence infection makes PCV2 recognized by central immune tolerance as belonging to the host. This also explains why pathogenicity is not a genetically intrinsic characteristic of PCV2; however, the dominance of any one PCV2 genotype group member leads to a more efficient deletion of the T cells against that specific genotype group member in the thymus. Full article

(This article belongs to the Special Issue Porcine Circovirus Infections)

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11 pages, 380 KiB

Open AccessArticle

Estimating the Percentage of a Population Infected with SARS-CoV-2 Using the Number of Reported Deaths: A Policy Planning Tool

by Daniel R. Feikin, Marc-Alain Widdowson and Kim Mulholland

Pathogens 2020, 9(10), 838; https://doi.org/10.3390/pathogens9100838 - 13 Oct 2020

Cited by 5 | Viewed by 2946

Abstract

The magnitude of future waves of Covid19 in a population will depend, in part, on the percentage of that population already infected, recovered, and presumably immune. Sero-epidemiological surveys can define the prevalence of SARS-CoV-2 antibodies in various populations. However, sero-surveys are resource-intensive and [...] Read more.

The magnitude of future waves of Covid19 in a population will depend, in part, on the percentage of that population already infected, recovered, and presumably immune. Sero-epidemiological surveys can define the prevalence of SARS-CoV-2 antibodies in various populations. However, sero-surveys are resource-intensive and methodologically challenging, limiting widespread use. We propose a relatively simple method for calculating the percentage of a population infected, which depends on the number of reported Covid19 deaths, a figure usually more reliable and less dependent on variable testing practices than the total number of reported Covid19 cases, and the infection fatality rate, a figure that is relatively stable in similar populations. The method can be applied in different sized areas, such as states, districts, or cities. Such an approach can provide useful, real-time estimates of probable population immunity in settings unable to undertake multiple sero-surveys. This method is applicable to low- and lower-middle-income country (LMIC) settings where sero-survey data will likely be limited; however, better estimates of infection fatality rates and Covid19 death counts in LMICs are needed to improve the method’s accuracy. Information on the percentage of a population infected will help public health authorities in planning for future waves of Covid19, including where to most effectively deploy vaccines. Full article

(This article belongs to the Special Issue COVID-19 in Low and Middle Income Countries)

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18 pages, 3104 KiB

Open AccessArticle

Insights into Genomic Epidemiology, Evolution, and Transmission Dynamics of Genotype VII of Class II Newcastle Disease Virus in China

by Bin Xiang, Libin Chen, Juncheng Cai, Jianpeng Liang, Qiuyan Lin, Chenggang Xu, Chan Ding, Ming Liao and Tao Ren

Pathogens 2020, 9(10), 837; https://doi.org/10.3390/pathogens9100837 - 13 Oct 2020

Cited by 18 | Viewed by 3856

Abstract

Newcastle disease virus (NDV) is distributed worldwide and has caused significant losses to the poultry industry. Almost all virulent NDV strains belong to class II, among which genotype VII is the predominant genotype in China. However, the molecular evolution and phylodynamics of class [...] Read more.

Newcastle disease virus (NDV) is distributed worldwide and has caused significant losses to the poultry industry. Almost all virulent NDV strains belong to class II, among which genotype VII is the predominant genotype in China. However, the molecular evolution and phylodynamics of class II genotype VII NDV strains in China remained largely unknown. In this study, we identified 13 virulent NDV including 11 genotype VII strains and 2 genotype IX strains, from clinical samples during 1997 to 2019. Combined NDV sequences submitted to GenBank, we investigate evolution, and transmission dynamics of class II NDVs in China, especially genotype VII strains. Our results revealed that East and South China have the most genotypic diversity of class II NDV, and East China might be the origin of genotype VII NDVs in China. In addition, genotype VII NDVs in China are presumably transmitted by chickens, as the virus was most prevalent in chickens. Furthermore, codon usage analysis revealed that the F genes of genotype VII NDVs have stronger adaptation in chickens, and six amino acids in this gene are found under positive selection via selection model analysis. Collectively, our results revealed the genetic diversity and evolutionary dynamics of genotype VII NDVs in China, providing important insights into the epidemiology of these viruses in China. Full article

(This article belongs to the Section Animal Pathogens)

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26 pages, 7849 KiB

Open AccessEditor’s ChoiceArticle

Effects of Naturally Occurring Mutations in Bovine Leukemia Virus 5′-LTR and Tax Gene on Viral Transcriptional Activity

by Aneta Pluta, Luc Willems, Renée N. Douville and Jacek Kuźmak

Pathogens 2020, 9(10), 836; https://doi.org/10.3390/pathogens9100836 - 13 Oct 2020

Cited by 13 | Viewed by 3122

Abstract

Bovine leukemia virus (BLV) is a deltaretrovirus infecting bovine B cells and causing enzootic bovine leucosis (EBL). The long terminal repeat (LTR) plays an indispensable role in viral gene expression. The BLV Tax protein acts as the main transactivator of LTR-driven transcription of [...] Read more.

Bovine leukemia virus (BLV) is a deltaretrovirus infecting bovine B cells and causing enzootic bovine leucosis (EBL). The long terminal repeat (LTR) plays an indispensable role in viral gene expression. The BLV Tax protein acts as the main transactivator of LTR-driven transcription of BLV viral genes. The aim of this study was to analyze mutations in the BLV LTR region and tax gene to determine their association with transcriptional activity. LTRs were obtained from one hundred and six BLV isolates and analyzed for their genetic variability. Fifteen variants were selected and characterized based on mutations in LTR regulatory elements, and further used for in vitro transcription assays. Reporter vectors containing the luciferase gene under the control of each variant BLV promoter sequence, in addition to variant Tax expression vectors, were constructed. Both types of plasmids were used for cotransfection of HeLa cells and the level of luciferase activity was measured as a proxy of transcriptional activity. Marked differences in LTR promoter activity and Tax transactivation activity were observed amongst BLV variants. These results demonstrate that mutations in both the BLV LTR and tax gene can affect the promoter activity, which may have important consequences on proviral load, viral fitness, and transmissibility in BLV-infected cattle. Full article

(This article belongs to the Collection Bovine Leukemia Virus Infection)

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20 pages, 3795 KiB

Open AccessEditor’s ChoiceArticle

Enterococcus faecalis Polymicrobial Interactions Facilitate Biofilm Formation, Antibiotic Recalcitrance, and Persistent Colonization of the Catheterized Urinary Tract

by Jordan R. Gaston, Marissa J. Andersen, Alexandra O. Johnson, Kirsten L. Bair, Christopher M. Sullivan, L. Beryl Guterman, Ashely N. White, Aimee L. Brauer, Brian S. Learman, Ana L. Flores-Mireles and Chelsie E. Armbruster

Pathogens 2020, 9(10), 835; https://doi.org/10.3390/pathogens9100835 - 13 Oct 2020

Cited by 46 | Viewed by 4872

Abstract

Indwelling urinary catheters are common in health care settings and can lead to catheter-associated urinary tract infection (CAUTI). Long-term catheterization causes polymicrobial colonization of the catheter and urine, for which the clinical significance is poorly understood. Through prospective assessment of catheter urine colonization, [...] Read more.

Indwelling urinary catheters are common in health care settings and can lead to catheter-associated urinary tract infection (CAUTI). Long-term catheterization causes polymicrobial colonization of the catheter and urine, for which the clinical significance is poorly understood. Through prospective assessment of catheter urine colonization, we identified Enterococcus faecalis and Proteus mirabilis as the most prevalent and persistent co-colonizers. Clinical isolates of both species successfully co-colonized in a murine model of CAUTI, and they were observed to co-localize on catheter biofilms during infection. We further demonstrate that P. mirabilis preferentially adheres to E. faecalis during biofilm formation, and that contact-dependent interactions between E. faecalis and P. mirabilis facilitate establishment of a robust biofilm architecture that enhances antimicrobial resistance for both species. E. faecalis may therefore act as a pioneer species on urinary catheters, establishing an ideal surface for persistent colonization by more traditional pathogens such as P. mirabilis. Full article

(This article belongs to the Special Issue Microbial Interactions during Infection)

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12 pages, 1858 KiB

Open AccessArticle

Genome Sequencing of Paecilomyces Penicillatus Provides Insights into Its Phylogenetic Placement and Mycoparasitism Mechanisms on Morel Mushrooms

by Xinxin Wang, Jingyu Peng, Lei Sun, Gregory Bonito, Yuxiu Guo, Yu Li and Yongping Fu

Pathogens 2020, 9(10), 834; https://doi.org/10.3390/pathogens9100834 - 13 Oct 2020

Cited by 26 | Viewed by 4008

Abstract

Morels (Morchella spp.) are popular edible fungi with significant economic and scientific value. However, white mold disease, caused by Paecilomyces penicillatus, can reduce morel yield by up to 80% in the main cultivation area in China. Paecilomyces is a polyphyletic genus [...] Read more.

Morels (Morchella spp.) are popular edible fungi with significant economic and scientific value. However, white mold disease, caused by Paecilomyces penicillatus, can reduce morel yield by up to 80% in the main cultivation area in China. Paecilomyces is a polyphyletic genus and the exact phylogenetic placement of P. penicillatus is currently still unclear. Here, we obtained the first high-quality genome sequence of P. penicillatus generated through the single-molecule real-time (SMRT) sequencing platform. The assembled draft genome of P. penicillatus was 40.2 Mb, had an N50 value of 2.6 Mb and encoded 9454 genes. Phylogenetic analysis of single-copy orthologous genes revealed that P. penicillatus is in Hypocreales and closely related to Hypocreaceae, which includes several genera exhibiting a mycoparasitic lifestyle. CAZymes analysis demonstrated that P. penicillatus encodes a large number of fungal cell wall degradation enzymes. We identified many gene clusters involved in the production of secondary metabolites known to exhibit antifungal, antibacterial, or insecticidal activities. We further demonstrated through dual culture assays that P. penicillatus secretes certain soluble compounds that are inhibitory to the mycelial growth of Morchella sextelata. This study provides insights into the correct phylogenetic placement of P. penicillatus and the molecular mechanisms that underlie P. penicillatus pathogenesis. Full article

(This article belongs to the Special Issue Genomics, Molecular, Genetics, and Diversity of Plant Disease Resistance)

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25 pages, 1620 KiB

Open AccessArticle

Screening of Fish Cell Lines for Piscine Orthoreovirus-1 (PRV-1) Amplification: Identification of the Non-Supportive PRV-1 Invitrome

by Phuc H. Pham, Ehab Misk, Fotini Papazotos, Ginny Jones, Mark P. Polinski, Elena Contador, Spencer Russell, Kyle A. Garver, John S. Lumsden and Niels C. Bols

Pathogens 2020, 9(10), 833; https://doi.org/10.3390/pathogens9100833 - 12 Oct 2020

Cited by 21 | Viewed by 3870

Abstract

Piscine reovirus (PRV) is the causative agent of heart and skeletal muscle inflammation (HSMI), which is detrimental to Atlantic Salmon (AS) aquaculture, but so far has not been cultivatable, which impedes studying the disease and developing a vaccine. Homogenates of head kidney and [...] Read more.

Piscine reovirus (PRV) is the causative agent of heart and skeletal muscle inflammation (HSMI), which is detrimental to Atlantic Salmon (AS) aquaculture, but so far has not been cultivatable, which impedes studying the disease and developing a vaccine. Homogenates of head kidney and red blood cells (RBC) from AS in which PRV-1 had been detected were applied to fish cell lines. The cell lines were from embryos, and from brain, blood, fin, gill, gonads, gut, heart, kidney, liver, skin, and spleen, and had the shapes of endothelial, epithelial, fibroblast, and macrophage cells. Most cell lines were derived from the Neopterygii subclass of fish, but one was from subclass Chondrostei. Cultures were examined by phase contrast microscopy for appearance, and by quantitative polymerase chain reaction (qPCR) for PRV-1 RNA amplification and for the capacity to transfer any changes to new cultures. No changes in appearance and Ct values were observed consistently or transferable to new cultures. Therefore, 31 cell lines examined were unable to support PRV-1 amplification and are described as belonging to the non-supportive PRV-1 invitrome. However, these investigations and cell lines can contribute to understanding PRV-1 cellular and host tropism, and the interactions between virus-infected and bystander cells. Full article

(This article belongs to the Special Issue Heart and Skeletal Muscle Inflammation (HSMI) and Other Effects of Piscine orthoreovirus (PRV) Infections in Salmonids)

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19 pages, 4519 KiB

Open AccessArticle

Clinical Characteristics of Acute Hepatitis E and Their Correlation with HEV Genotype 3 Subtypes in Italy

by Claudia Minosse, Elisa Biliotti, Daniele Lapa, Alessia Rianda, Mauro Marchili, Ilaria Luzzitelli, Maria Rosaria Capobianchi, Fiona McPhee, Anna Rosa Garbuglia and Gianpiero D’Offizi

Pathogens 2020, 9(10), 832; https://doi.org/10.3390/pathogens9100832 - 11 Oct 2020

Cited by 10 | Viewed by 2477

Abstract

Genotype 3 (GT3) is responsible for most European autochthonous hepatitis E virus (HEV) infections. This study analyzed circulating genotypes and GT3 subtypes in the Lazio region, Italy, between 2011 and 2019, as well as their pathogenic characteristics. Of the 64 evaluable HEV GT3 [...] Read more.

Genotype 3 (GT3) is responsible for most European autochthonous hepatitis E virus (HEV) infections. This study analyzed circulating genotypes and GT3 subtypes in the Lazio region, Italy, between 2011 and 2019, as well as their pathogenic characteristics. Of the 64 evaluable HEV GT3 patient-derived sequences, identified subtypes included GT3f (n = 36), GT3e (n = 15), GT3c (n = 9), GT3a (n = 1) and three unsubtyped GT3 sequences. GT3c strains were similar to Dutch sequences (96.8–98.1% identity), GT3e strains showed high similarity (96.8%) with a United Kingdom sequence, while the most related sequences to GT3f Italian strains were isolated in France, Belgium and Japan. One sequence was closely related to another Italian strain isolated in raw sewage in 2016. The liver functioning test median values for 56 evaluable GT3 patients were: alanine aminotransferase (ALT), 461 (range 52–4835 U/L); aspartate aminotransferase (AST), 659 (range 64–6588 U/L); and total bilirubin, 3.49 (range 0.4–33 mg/dL). The median HEV RNA viral load for 26 evaluable GT3 patients was 42,240 IU/mL (range 5680–895,490 IU/mL). Of the 37 GT3 patients with available clinical information, no correlation was observed between HEV clinical manifestations and GT3 subtype. HEV symptoms were comparable among GT3c/e/f patients across most analyzed categories except for epigastric pain, which occurred more frequently in patients with HEV GT3e (75%) than in patients with GT3c (50%) or GT3f (19%) (p = 0.01). Additionally, patients with HEV GT3c exhibited significantly higher median international normalized ratio (INR) than patients with GT3e and GT3f (p = 0.033). The severity of GT3 acute hepatitis E was not linked to HEV RNA viral load or to the GT3 subtype. Full article

(This article belongs to the Special Issue Hepatitis E Virus (HEV) Infections)

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10 pages, 12123 KiB

Open AccessArticle

Bacteriophage Cocktail for the Prevention of Multiple-Antibiotic-Resistant and Mono-Phage-Resistant Vibrio coralliilyticus Infection in Pacific Oyster (Crassostrea gigas) Larvae

by Hyoun Joong Kim, Jin Woo Jun, Sib Sankar Giri, Sang Guen Kim, Sang Wha Kim, Jun Kwon, Sung Bin Lee, Cheng Chi and Se Chang Park

Pathogens 2020, 9(10), 831; https://doi.org/10.3390/pathogens9100831 - 11 Oct 2020

Cited by 21 | Viewed by 3448

Abstract

Vibrio coralliilyticus (V. coralliilyticus) is a pathogen that causes mass mortality in marine bivalve hatcheries worldwide. In this study, we used a bacteriophage (phage) cocktail to prevent multiple-antibiotic-resistant (MAR) and phage-resistant (PR) V. coralliilyticus infection in Pacific oyster (Crassostreagigas [...] Read more.

Vibrio coralliilyticus (V. coralliilyticus) is a pathogen that causes mass mortality in marine bivalve hatcheries worldwide. In this study, we used a bacteriophage (phage) cocktail to prevent multiple-antibiotic-resistant (MAR) and phage-resistant (PR) V. coralliilyticus infection in Pacific oyster (Crassostreagigas) larvae. To prevent the occurrence of phage-resistant strains and decrease the effect of mono-phage treatment, we prepared a phage cocktail containing three types of V. coralliilyticus-specific phages and tested its prophylactic efficacy against MAR and PR V. coralliilyticus infection. The results of the cell lysis test showed that the phage cocktail showed an excellent bactericidal effect against the MAR and PR variants in contrast to the experimental group treated with two mono phages (pVco-5 and pVco-7). An in vivo test using Pacific oyster larvae also confirmed the preventive effect against MAR and PR variants. In conclusion, the application of the phage cocktail effectively prevented V. coralliilyticus infection in marine bivalve seedling production. Furthermore, it is expected to reduce damage to the aquaculture industry caused by the occurrence of MAR and PR V. coralliilyticus. Therefore, phage cocktails may be used for the control of various bacterial diseases. Full article

(This article belongs to the Special Issue Phage Therapy in Aquaculture: Current Developments and Future Challenges)

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