Research

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22 pages, 3973 KiB

Open AccessArticle

Molecular Characterization of Chimeric Staphylococcus aureus Strains from Waterfowl

by Stefan Monecke, Sascha D. Braun, Maximillian Collatz, Celia Diezel, Elke Müller, Martin Reinicke, Adriana Cabal Rosel, Andrea T. Feßler, Dennis Hanke, Igor Loncaric, Stefan Schwarz, Sonia Cortez de Jäckel, Werner Ruppitsch, Dolores Gavier-Widén, Helmut Hotzel and Ralf Ehricht

Microorganisms 2024, 12(1), 96; https://doi.org/10.3390/microorganisms12010096 - 03 Jan 2024

Viewed by 920

Abstract

Staphylococcus aureus is a versatile pathogen that does not only occur in humans but also in various wild and domestic animals, including several avian species. When characterizing S. aureus isolates from waterfowl, isolates were identified as atypical CC133 by DNA microarray analysis. They [...] Read more.

Staphylococcus aureus is a versatile pathogen that does not only occur in humans but also in various wild and domestic animals, including several avian species. When characterizing S. aureus isolates from waterfowl, isolates were identified as atypical CC133 by DNA microarray analysis. They differed from previously sequenced CC133 strains in the presence of the collagen adhesin gene cna; some also showed a different capsule type and a deviant spa type. Thus, they were subjected to whole-genome sequencing. This revealed multiple insertions of large regions of DNA from other S. aureus lineages into a CC133-derived backbone genome. Three distinct strains were identified based on the size and extent of these inserts. One strain comprised two small inserts of foreign DNA up- and downstream of oriC; one of about 7000 nt or 0.25% originated from CC692 and the other, at ca. 38,000 nt or 1.3% slightly larger one was of CC522 provenance. The second strain carried a larger CC692 insert (nearly 257,000 nt or 10% of the strain’s genome), and its CC522-derived insert was also larger, at about 53,500 nt or 2% of the genome). The third strain carried an identical CC692-derived region (in which the same mutations were observed as in the second strain), but it had a considerably larger CC522-like insertion of about 167,000 nt or 5.9% of the genome. Both isolates of the first, and two out of four isolates of the second strain also harbored a hemolysin-beta-integrating prophage carrying “bird-specific” virulence factors, ornithine cyclodeaminase D0K6J8 and a putative protease D0K6J9. Furthermore, isolates had two different variants of SCC elements that lacked mecA/mecC genes. These findings highlight the role of horizontal gene transfer in the evolution of S. aureus facilitated by SCC elements, by phages, and by a yet undescribed mechanism for large-scale exchange of core genomic DNA. Full article

(This article belongs to the Special Issue Pathogen Infection in Wildlife)

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12 pages, 831 KiB

Open AccessArticle

Prevalence and Risk Factors for Hepatitis E Virus in Wild Boar and Red Deer in Portugal

by Humberto Pires, Luís Cardoso, Ana Patrícia Lopes, Maria da Conceição Fontes, Sérgio Santos-Silva, Manuela Matos, Cristina Pintado, Luís Figueira, Ana Cristina Matos, João Rodrigo Mesquita and Ana Cláudia Coelho

Microorganisms 2023, 11(10), 2576; https://doi.org/10.3390/microorganisms11102576 - 16 Oct 2023

Cited by 1 | Viewed by 1385

Abstract

Hepatitis E virus (HEV) is a zoonotic foodborne virus with an annual infection prevalence of 20 million human cases, which seriously affects public health and economic development in both developed and developing countries. To better understand the epidemiology of HEV in Central Portugal, [...] Read more.

Hepatitis E virus (HEV) is a zoonotic foodborne virus with an annual infection prevalence of 20 million human cases, which seriously affects public health and economic development in both developed and developing countries. To better understand the epidemiology of HEV in Central Portugal, a cross-sectional study was conducted from 2016 to 2023 with sera samples from wild ungulates. The seroprevalence and risk factors for HEV seropositivity were evaluated in the present study. Specifically, antibodies against HEV were determined by a commercial enzyme-linked immune-sorbent assay (ELISA). Our results show that in the 650 sera samples collected from 298 wild red deer and 352 wild boars in Portugal, 9.1% red deer and 1.7% wild boar were positive for antibodies to HEV. Regarding age, the seropositivity in juvenile wild ungulates was 1.3%, whereas it was 7.2% in adults. Logistic regression models investigated risk factors for seropositivity. The odds of being seropositive was 3.6 times higher in adults than in juveniles, and the risk was 4.2 times higher in red deer than in wild boar. Both wild ungulate species were exposed to HEV. The higher seroprevalence in red deer suggests that this species may make a major contribution to the ecology of HEV in Central Portugal. Further research is needed to understand how wildlife affects the epidemiology of HEV infections in Portugal. Full article

(This article belongs to the Special Issue Pathogen Infection in Wildlife)

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19 pages, 7331 KiB

Open AccessArticle

Reevaluation of Hemoparasites in the Black Spiny-Tailed Iguana (Ctenosaura similis) with the First Pathological and Molecular Characterizations of Lankesterella desseri n. sp. and Redescription of Hepatozoon gamezi

by Yen-Chi Chang, Tai-Shen Lin, Wei-Wen Huang, Hung-Yi Lee, Cheng-Hsin Shih, Ying-Chen Wu, Chiu-Chen Huang and Ter-Hsin Chen

Microorganisms 2023, 11(10), 2374; https://doi.org/10.3390/microorganisms11102374 - 22 Sep 2023

Viewed by 1006

Abstract

Hemoprotozoa are microorganisms that parasitize the blood and possess intricate life cycles. Despite the complexity of their nature, little is known about the biology of hemoprotozoa in reptilian hosts. In this study, we conducted disease surveillance on blood samples collected from six black [...] Read more.

Hemoprotozoa are microorganisms that parasitize the blood and possess intricate life cycles. Despite the complexity of their nature, little is known about the biology of hemoprotozoa in reptilian hosts. In this study, we conducted disease surveillance on blood samples collected from six black spiny-tailed iguanas (Ctenosaura similis) exhibiting clinical signs. We found two different types of hemoparasites in the blood films and further confirmed they belong to the genera Lakesterella and Hepatozoon through molecular methods. In the tissue section from a dead iguana infected only with Lakesterella sp., parasites were also found in melanomacrophages of the liver and kidney. Since Lakesterella sp. infection has not been reported in C. similis, we propose this hemococcidian as a new species, Lankesterella desseri n. sp. The Hepatozoon parasites discovered in this study were classified as Hepatozoon gamezi based on their morphological characteristics, particularly the notable deformation of all infected erythrocytes, and this classification was further corroborated through molecular biological and phylogenetic analyses. This is the first hemoprotozoa investigation in C. similis with pathological and molecular characterization of these pathogens. We suggest that more studies are needed to understand the epidemiology, transmission, and impact of these parasites on their hosts and ecosystems. Full article

(This article belongs to the Special Issue Pathogen Infection in Wildlife)

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11 pages, 1569 KiB

Open AccessCommunication

Rotaviruses in Wild Ungulates from Germany, 2019–2022

by Nadine Althof, Eva Trojnar and Reimar Johne

Microorganisms 2023, 11(3), 566; https://doi.org/10.3390/microorganisms11030566 - 24 Feb 2023

Cited by 2 | Viewed by 1218

Abstract

Rotavirus A (RVA) is an important cause of diarrhea in humans and animals. However, RVA in wild animals has only scarcely been investigated so far. Here, the presence of RVA in wild ungulates hunted between 2019 and 2022 in Brandenburg, Germany, was investigated [...] Read more.

Rotavirus A (RVA) is an important cause of diarrhea in humans and animals. However, RVA in wild animals has only scarcely been investigated so far. Here, the presence of RVA in wild ungulates hunted between 2019 and 2022 in Brandenburg, Germany, was investigated using real-time RT-PCR and sequencing of RT-PCR products. By analyzing intestinal contents, RVA-RNA was detected in 1.0% (2/197) of wild boar (Sus scrofa), 1.3% (2/152) of roe deer (Capreolus capreolus), and 2.1% (2/95) of fallow deer (Dama dama) but not in 28 red deer (Cervus elaphus) samples. Genotyping identified G3P[13] strains in wild boar, which were closely related to previously described pig and wild boar strains. Genotype G10P[15] strains, closely related to strains from roe deer, sheep, or cattle, were found in roe deer. The strains of fallow deer represented genotype G3P[3], clustering in a group containing different strains from several hosts. The results indicated a low prevalence of RVA in wild ungulates in Germany. Associations of specific genotypes with certain ungulate species seem to exist but should be confirmed by analyses of more samples in the future. Full article

(This article belongs to the Special Issue Pathogen Infection in Wildlife)

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18 pages, 2368 KiB

Open AccessArticle

The Infection Rate of Bird-Feeding Ixodes ricinus Ticks with Borrelia garinii and B. valaisiana Varies with Host Haemosporidian Infection Status

by Alžbeta Šujanová, Zuzana Čužiová and Radovan Václav

Microorganisms 2023, 11(1), 60; https://doi.org/10.3390/microorganisms11010060 - 25 Dec 2022

Viewed by 1513

Abstract

Background: Birds are known to maintain and spread human pathogenic borreliae, but they are common hosts of diverse parasite communities, notably haemosporidians. Only a few studies examined whether tick infestation and/or Borrelia prevalences vary with hosts’ haemosporidian infection status. Methods: Here, we study [...] Read more.

Background: Birds are known to maintain and spread human pathogenic borreliae, but they are common hosts of diverse parasite communities, notably haemosporidians. Only a few studies examined whether tick infestation and/or Borrelia prevalences vary with hosts’ haemosporidian infection status. Methods: Here, we study whether Ixodes ricinus infestation rates and Borrelia infection rates in bird-feeding ticks vary according to haemosporidian infection status in a community of free-living avian tick hosts. Results: Birds of six avian species harbored the majority of ticks. Both the tick infestation prevalence and the intensity peaked during spring and summer, but while bird-feeding nymphs prevailed in spring, bird-feeding larvae dominated in summer. Almost half of the bird-feeding ticks were found to be positive for B. burgdorferi s.l. Although the majority of infections involved bird-associated B. garinii and B. valaisiana, B. garinii appears to be the dominant Borrelia strain circulating in locally breeding avian species. We detected a negative link between the hosts’ haemosporidian infection status and the Borrelia infection rate of bird-feeding ticks, but the association was dependent on the host’s age. Conclusions: Our results on tick infestation intensity support the idea that more immunologically vulnerable hosts harbor more ticks but suggest that different mechanisms may be responsible for tick infestation rates among immunologically naïve and experienced avian hosts. The results on Borrelia infection rates in bird-feeding ticks are consistent with studies revealing that intracellular parasites, such as haemosporidians, can benefit from the host immune system prioritizing immune responses against extracellular parasites at the expense of immune responses against intracellular parasites. The findings of our study urge for a more robust design of parasitological studies to understand the ecology of interactions among hosts and their parasites. Full article

(This article belongs to the Special Issue Pathogen Infection in Wildlife)

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14 pages, 2709 KiB

Open AccessArticle

StcU-2 Gene Mutation via CRISPR/Cas9 Leads to Misregulation of Spore-Cyst Formation in Ascosphaera apis

by Tessema Aynalem, Lifeng Meng, Awraris Getachew, Jiangli Wu, Huimin Yu, Jing Tan, Nannan Li and Shufa Xu

Microorganisms 2022, 10(10), 2088; https://doi.org/10.3390/microorganisms10102088 - 21 Oct 2022

Cited by 2 | Viewed by 1596

Abstract

Ascosphaera apis is the causative agent of honey bee chalkbrood disease, and spores are the only known source of infections. Interference with sporulation is therefore a promising way to manage A. apis. The versicolorin reductase gene (StcU-2) is a ketoreductase protein [...] Read more.

Ascosphaera apis is the causative agent of honey bee chalkbrood disease, and spores are the only known source of infections. Interference with sporulation is therefore a promising way to manage A. apis. The versicolorin reductase gene (StcU-2) is a ketoreductase protein related to sporulation and melanin biosynthesis. To study the StcU-2 gene in ascospore production of A. apis, CRISPR/Cas9 was used, and eight hygromycin B antibiotic-resistant transformants incorporating enhanced green fluorescent protein (EGFP) were made and analyzed. PCR amplification, gel electrophoresis, and sequence analysis were used for target gene editing analysis and verification. The CRISPR/Cas9 editing successfully knocked out the StcU-2 gene in A. apis. StcU-2 mutants had shown albino and non-functional spore-cyst development and lost effective sporulation. In conclusion, editing of StcU-2 gene has shown direct relation with sporulation and melanin biosynthesis of A. apis; this effective sporulation reduction would reduce the spread and pathogenicity of A. apis to managed honey bee. To the best of our knowledge, this is the first time CRISPR/Cas9-mediated gene editing has been efficiently performed in A. apis, a fungal honey bee brood pathogen, which offers a comprehensive set of procedural references that contributes to A. apis gene function studies and consequent control of chalkbrood disease. Full article

(This article belongs to the Special Issue Pathogen Infection in Wildlife)

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14 pages, 1797 KiB

Open AccessArticle

Identification and Characterisation of Nontuberculous Mycobacteria in African Buffaloes (Syncerus caffer), South Africa

by Charlene Clarke, Tanya J. Kerr, Robin M. Warren, Léanie Kleynhans, Michele A. Miller and Wynand J. Goosen

Microorganisms 2022, 10(9), 1861; https://doi.org/10.3390/microorganisms10091861 - 17 Sep 2022

Cited by 5 | Viewed by 2182

Abstract

Diagnosis of bovine tuberculosis (bTB) may be confounded by immunological cross-reactivity to Mycobacterium bovis antigens when animals are sensitised by certain nontuberculous mycobacteria (NTMs). Therefore, this study aimed to investigate NTM species diversity in African buffalo (Syncerus caffer) respiratory secretions and [...] Read more.

Diagnosis of bovine tuberculosis (bTB) may be confounded by immunological cross-reactivity to Mycobacterium bovis antigens when animals are sensitised by certain nontuberculous mycobacteria (NTMs). Therefore, this study aimed to investigate NTM species diversity in African buffalo (Syncerus caffer) respiratory secretions and tissue samples, using a combination of novel molecular tools. Oronasal swabs were collected opportunistically from 120 immobilised buffaloes in historically bTB-free herds. In addition, bronchoalveolar lavage fluid (BALF; n = 10) and tissue samples (n = 19) were obtained during post-mortem examination. Mycobacterial species were identified directly from oronasal swab samples using the Xpert MTB/RIF Ultra qPCR (14/120 positive) and GenoType CMdirect (104/120 positive). In addition, all samples underwent mycobacterial culture, and PCRs targeting hsp65 and rpoB were performed. Overall, 55 NTM species were identified in 36 mycobacterial culture-positive swab samples with presence of esat-6 or cfp-10 detected in 20 of 36 isolates. The predominant species were M. avium complex and M. komanii. Nontuberculous mycobacteria were also isolated from 6 of 10 culture-positive BALF and 4 of 19 culture-positive tissue samples. Our findings demonstrate that there is a high diversity of NTMs present in buffaloes, and further investigation should determine their role in confounding bTB diagnosis in this species. Full article

(This article belongs to the Special Issue Pathogen Infection in Wildlife)

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19 pages, 2625 KiB

Open AccessArticle

Phylogeographic Patterns of Haemoproteid Assemblages of Selected Avian Hosts: Ecological and Evolutionary Implications

by Alžbeta Šujanová and Radovan Václav

Microorganisms 2022, 10(5), 1019; https://doi.org/10.3390/microorganisms10051019 - 12 May 2022

Cited by 1 | Viewed by 1778

Abstract

Background: While the dynamics of disease emergence is driven by host–parasite interactions, the structure and dynamics of these interactions are still poorly understood. Here we study the phylogenetic and morphological clustering of haemosporidian parasite lineages in a local avian host community. Subsequently, we [...] Read more.

Background: While the dynamics of disease emergence is driven by host–parasite interactions, the structure and dynamics of these interactions are still poorly understood. Here we study the phylogenetic and morphological clustering of haemosporidian parasite lineages in a local avian host community. Subsequently, we examine geographical patterns of parasite assemblages in selected avian hosts breeding in Europe. Methods: We conduct phylogenetic and haplotype network analyses of Haemoproteus (Parahaemoproteus) lineages based on a short and an extended cytochrome b barcode region. Ordination analyses are used to examine changes in parasite assemblages with respect to climate type and geography. Results: We reveal relatively low phylogenetic clustering of haemoproteid lineages in a local avian host community and identify a potentially new Haemoproteus morphospecies. Further, we find that climate is effectively capturing geographical changes in parasite assemblages in selected widespread avian hosts. Moreover, parasite assemblages are found to vary distinctly across the host’s breeding range, even within a single avian host. Conclusions: This study suggests that a few keystone hosts can be important for the local phylogenetic and morphological clustering of haemoproteid parasites. Host spatio-temporal dynamics, both for partially and long-distance migratory birds, appear to explain geographical variation in haemoproteid parasite assemblages. This study also gives support to the idea that climate variation in terms of rainfall seasonality can be linked to the propensity for host switching in haemosporidians. Full article

(This article belongs to the Special Issue Pathogen Infection in Wildlife)

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Review

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10 pages, 577 KiB

Open AccessReview

Opportunities and Limitations of Molecular Methods for Studying Bat-Associated Pathogens

by Silvia Zemanová, Ľuboš Korytár, Jana Tomčová, Marián Prokeš, Monika Drážovská, Łukasz Myczko, Piotr Tryjanowski, Gréta Nusová, Alicja Matysiak and Anna Ondrejková

Microorganisms 2022, 10(9), 1875; https://doi.org/10.3390/microorganisms10091875 - 19 Sep 2022

Cited by 2 | Viewed by 2255

Abstract

Bats have been identified as reservoirs of zoonotic and potentially zoonotic pathogens. Significant progress was made in the field of molecular biology with regard to infectious diseases, especially those that infect more than one species. Molecular methods, sequencing and bioinformatics have recently become [...] Read more.

Bats have been identified as reservoirs of zoonotic and potentially zoonotic pathogens. Significant progress was made in the field of molecular biology with regard to infectious diseases, especially those that infect more than one species. Molecular methods, sequencing and bioinformatics have recently become irreplaceable tools in emerging infectious diseases research and even outbreak prediction. Modern methods in the molecular biology field have shed more light on the unique relationship between bats and viruses. Here we provide readers with a concise summary of the potential and limitations of molecular methods for studying the ecology of bats and bat-related pathogens and microorganisms. Full article

(This article belongs to the Special Issue Pathogen Infection in Wildlife)

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32 pages, 1334 KiB

Open AccessReview

Evidence, Challenges, and Knowledge Gaps Regarding Latent Tuberculosis in Animals

by Pamela Ncube, Bahareh Bagheri, Wynand Johan Goosen, Michele Ann Miller and Samantha Leigh Sampson

Microorganisms 2022, 10(9), 1845; https://doi.org/10.3390/microorganisms10091845 - 15 Sep 2022

Cited by 5 | Viewed by 3678

Abstract

Mycobacterium bovis and other Mycobacterium tuberculosis complex (MTBC) pathogens that cause domestic animal and wildlife tuberculosis have received considerably less attention than M. tuberculosis, the primary cause of human tuberculosis (TB). Human TB studies have shown that different stages of infection can [...] Read more.

Mycobacterium bovis and other Mycobacterium tuberculosis complex (MTBC) pathogens that cause domestic animal and wildlife tuberculosis have received considerably less attention than M. tuberculosis, the primary cause of human tuberculosis (TB). Human TB studies have shown that different stages of infection can exist, driven by host–pathogen interactions. This results in the emergence of heterogeneous subpopulations of mycobacteria in different phenotypic states, which range from actively replicating (AR) cells to viable but slowly or non-replicating (VBNR), viable but non-culturable (VBNC), and dormant mycobacteria. The VBNR, VBNC, and dormant subpopulations are believed to underlie latent tuberculosis (LTB) in humans; however, it is unclear if a similar phenomenon could be happening in animals. This review discusses the evidence, challenges, and knowledge gaps regarding LTB in animals, and possible host–pathogen differences in the MTBC strains M. tuberculosis and M. bovis during infection. We further consider models that might be adapted from human TB research to investigate how the different phenotypic states of bacteria could influence TB stages in animals. In addition, we explore potential host biomarkers and mycobacterial changes in the DosR regulon, transcriptional sigma factors, and resuscitation-promoting factors that may influence the development of LTB. Full article

(This article belongs to the Special Issue Pathogen Infection in Wildlife)

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