Molecular and serological characterization of pathogenic Leptospira spp. isolated from symptomatic dogs in a highly endemic area, Brazil

Abstract Background Leptospirosis is an endemic zoonosis in Brazil, with a great impact on human and animal health. Although dogs are frequently infected by pathogenic Leptospira, the current epidemiological understanding of canine leptospirosis is mainly based on serological tests that predict the infecting serogroup/serovar. Thus, the present study aimed at identifying the causative agent for severe cases of canine leptospirosis in a highly endemic area through the isolation and characterization of the isolated strains. Results Urine, serum and blood samples were collected from 31 dogs with suspected acute leptospirosis treated at the Veterinary Hospital Service of Santo Amaro University between 2018 and 2019. Acute infection was confirmed in 17 dogs (54.8%) by the associated use of Polymerase Chain Reaction (PCR), Microscopic Agglutination (MAT) and bacteriological culture. Eleven dogs (35.5%) had titers ≥800, with the most frequent serogroups being Autumnalis and Icterohaemorrhagiae (n = 4 each) and Canicola (n = 2). Leptospires were recovered from four dogs, and Multilocus Sequence Analysis (MLSA) revealed infection caused by L. interrogans, which were further characterized as serogroups Canicola (n = 1) and Icterohaemorrhagiae (n = 3). Conclusion The identity of the isolates and serological pattern of MAT suggest that dogs are highly exposed to the serogroup Icterohaemorrhagiae and Canicola, also indicating possible circulation of serogroups not yet isolated in Brazil, notably serogroup Autumnalis. Our findings also reinforce the usefulness of using multiple diagnostic approaches to confirm acute canine leptospirosis.

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Molecular and Serological Characterization of Pathogenic Leptospira Spp. Isolated From Symptomatic Dogs in a Highly Endemic Area, Brazil

10.21203/rs.3.rs-230543/v1 ◽

2021 ◽

Author(s):

Cassia Moreira Santos ◽

Gabrielle Cristini Del Rigo Santos Dias ◽

Alexya Victória Pinheiro Saldanha ◽

Stephanie Bergmann Esteves ◽

Adriana Cortez ◽

...

Keyword(s):

Endemic Area ◽

Animal Health ◽

Acute Infection ◽

Serological Tests ◽

Pathogenic Leptospira ◽

Effective Prevention ◽

Isolation And Characterization ◽

Serological Characterization ◽

Veterinary Hospital

Abstract Background: Leptospirosis is an endemic zoonosis in Brazil, with great impact in human and animal health. Although dogs are frequently infected by pathogenic Leptospira, the current epidemiological understanding of canine leptospirosis is mainly based on serological tests that predict the infecting serogroup/serovar. Thus, the present study aimed at identifying the causative agent for severe cases of canine leptospirosis in a highly endemic area through the isolation and characterization of the isolated strains. Results: Urine, serum and blood samples were collected from 31 dogs with suspected acute leptospirosis treated at the Veterinary Hospital Service of Santo Amaro University between 2018 and 2019. Acute infection was confirmed in 17 dogs (54.8%) by the associated use of Polymerase Chain Reaction (PCR), Microscopic Agglutination (MAT) and bacteriological culture. Eleven dogs (35.5%) had titers ≥800, with the most frequent serogroups being Autumnalis and Icterohaemorrhagiae (n = 4 each) and Canicola (n = 2). Leptospires were recovered from four dogs, and Multilocus Sequence Analysis (MLSA) revealed infection caused by L. interrogans, which were further characterized as serogroups Canicola (n=1) and Icterohaemorrhagiae (n=3). Conclusion: The identification of circulating strains in poverty-stricken locations with humans living in rural-urban interfaces may assist local authorities to implement effective prevention policies. The identity of the isolates and serological pattern of MAT titers found among the suspected dogs suggest that dogs are highly exposed to the serogroup Icterohaemorrhagiae, also indicating possible circulation of serogroups not yet isolated in Brazil, notably serogroup Autumnalis.

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Evaluation of the discriminatory power of spoligotyping and 19-locus mycobacterial interspersed repetitive unit-variable number of tandem repeat analysis (MIRU-VNTR) of Mycobacterium bovis strains isolated from cattle in Algeria

PLoS ONE ◽

10.1371/journal.pone.0262390 ◽

2022 ◽

Vol 17 (1) ◽

pp. e0262390

Author(s):

Faïza Belakehal ◽

Stefanie A. Barth ◽

Christian Menge ◽

Hamdi T. Mossadak ◽

Naïm Malek ◽

...

Keyword(s):

Animal Health ◽

Small Ruminants ◽

Variable Number ◽

Discriminatory Power ◽

Repeat Analysis ◽

Isolation And Characterization ◽

Cattle Herds ◽

World Organization ◽

Discriminatory Index

Bovine tuberculosis (bTB) caused by Mycobacterium (M.) bovis and M. caprae is a transmissible disease of livestock, notifiable to the World Organization for Animal Health (OIE). BTB particularly affects cattle and small ruminants and can be transmitted to humans thereby posing a significant threat to veterinary and public health worldwide. M. bovis is the principal cause of bTB in Algeria. In order to better understand the route of spreading and elaborate an eradication program, isolation and characterization of mycobacteria from Algerian cattle was performed. Sixty strains belonging to the M. tuberculosis complex were analyzed by spoligotyping, thereof 42 by 19-locus-MIRU-VNTR-typing. Spoligotyping revealed 16 distinguishable patterns (Hunter-Gaston discriminatory index [HGDI] of 0.8294), with types SB0120 (n = 20) and SB0121 (n = 13) being the most frequent patterns, representing 55% of the strains. Analyses based on 19-locus-MIRU-VNTR yielded 32 different profiles, five clusters and one orphan pattern, showing higher discriminatory power (HGDI = 0.9779) than spoligotyping. Seven VNTR-loci [VNTR 577 (alias ETR C), 2163b (QU11b), 2165 (ETR A), 2461 (ETR B), 3007 (MIRU 27), 2163a (QUB11a) and 3232 (QUB 3232)] were the most discriminative loci (HGDI ˃ 0.50). In conclusion, 19-locus-MIRU-VNTR yielded more information than spoligotyping concerning molecular differentiation of strains and better supports the elucidation of transmission routes of M. bovis between Algerian cattle herds.

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Cultivation and Serological Characterization of a Human Theiler's-Like Cardiovirus Associated with Diarrheal Disease

Journal of Virology ◽

10.1128/jvi.02536-09 ◽

2010 ◽

Vol 84 (9) ◽

pp. 4407-4414 ◽

Cited By ~ 36

Author(s):

C. Y. Chiu ◽

A. L. Greninger ◽

E. C. Chen ◽

T. D. Haggerty ◽

J. Parsonnet ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Diarrheal Disease ◽

Genotype 3 ◽

Isolation And Characterization ◽

Serological Characterization ◽

Genotype 2 ◽

Encephalomyelitis Virus ◽

Blocking Antibodies

ABSTRACT Cardioviruses (e.g., Theiler's murine encephalomyelitis virus [TMEV]) are members of the Picornaviridae family that cause myocarditis and encephalitis in rodents. Recently, several studies have identified human cardioviruses, including Saffold virus (SAFV) and a related virus named human TMEV-like cardiovirus (HTCV). At least eight cardiovirus genotypes are now recognized, with SAFV and most strains of HTCV belonging to genotypes 1 and 2, respectively; genotype 2 strains are the most common in the population. Although a genotype 3 cardiovirus has recently been cultured (SAFV-3), the genotype 1 and 2 cardioviruses have been difficult to propagate in vitro, hindering efforts to understand their seroprevalence and pathogenicity. Here we present the isolation and characterization of a genotype 2 human cardiovirus (HTCV-UC6). Notably, successful cultivation of HTCV-UC6 from stool required the addition of cytokine-blocking antibodies to interrupt downstream antiviral pathways. Unlike SAFV-3, HTCV-UC6 exhibited slow replication kinetics and demonstrated only a moderate cytopathic effect. Serologic assays revealed that 91% of U.S. adults carry antibodies to the genotype 2 cardioviruses, of which 80% generate neutralizing antibodies, in agreement with previous data showing that cardiovirus infection is widespread in humans. We also demonstrate an acute cardiovirus seroconversion event in a child with diarrhea and vomiting, thus reporting for the first time evidence linking cardiovirus infection to diarrheal disease in humans.

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Genomic and phylogenetic characterization of Leanyer virus, a novel orthobunyavirus isolated in northern Australia

Journal of General Virology ◽

10.1099/vir.0.028308-0 ◽

2011 ◽

Vol 92 (7) ◽

pp. 1676-1687 ◽

Cited By ~ 19

Author(s):

Nazir Savji ◽

Gustavo Palacios ◽

Amelia Travassos da Rosa ◽

Stephen Hutchison ◽

Christopher Celone ◽

...

Keyword(s):

Northern Territory ◽

Northern Australia ◽

Serological Tests ◽

Phylogenetic Characterization ◽

Serological Characterization ◽

The Family ◽

Antigenic Complex ◽

Relationship Of ◽

The Relationship

Leanyer virus (LEAV), currently classified as a member of the genus Orthobunyavirus, in the family Bunyaviridae, was originally isolated from a pool of Anopheles meraukensis mosquitoes, collected at Leanyer, Northern Territory, Australia in 1974. When it failed to react in serological tests with antisera from other known viruses, full-length genomic sequencing was pursued to determine the relationship of LEAV to other orthobunyavirus species. Genetic and serological characterization confirmed its antigenic distance from other orthobunyaviruses, including to its closest genetic neighbours, the Simbu group viruses, suggesting that it may represent a new antigenic complex.

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Isolation and Characterization of Salmonella Serovars from Buffaloes in Mymensingh, Bangladesh

Microbes and Health ◽

10.3329/mh.v1i2.14092 ◽

2013 ◽

Vol 1 (2) ◽

pp. 62-64

Author(s):

Nahid Rahman ◽

Md Shahidur Rahman Khan ◽

Md Mansurul Amin ◽

Mahbubul Pratik Siddique ◽

Jayedul Hassan ◽

...

Keyword(s):

Antibiotic Sensitivity ◽

Agglutination Test ◽

Methyl Red ◽

Salmonella Spp ◽

Serological Tests ◽

Isolation And Characterization ◽

Highly Sensitive ◽

Salmonella Serovars ◽

Apparently Healthy

An investigation was carried out focusing the isolation and characterization of Salmonella serovars from buffaloes of some selected areas of Mymensingh district of Bangladesh. The objectives was to isolate and identify Salmonella serovars from diarrheic and apparently healthy buffaloes and to characterize the isolates by cultural and biochemical characteristics, serological tests and antibiotic sensitivity analysis. A total of 38 samples comprising rectal swabs and faeces were collected from 38 buffaloes originating from 3 selected areas of Mymensingh. Out of these 38 samples, 8 (20.63%) were found to be positive for Salmonella spp. All isolates fermented dextrose, maltose and mannitol with production of acid and gas but did not ferment sucrose and lactose. On the other hand, these isolates showed Indole and Voges- Proskaure test negative, Methyl-Red test positive. All these isolates subjected to rapid plate agglutination test with polyvalent O ( poly ?O) and polyvalent H ( poly ?H) antisera where positive agglutination were observed. All isolates were highly sensitive to ciprofloxacin, moderately sensitive to co-trimoxazole, gentamycin, tetracycline and less sensitive to erythromycin and resistant to furazolidone. DOI: http://dx.doi.org/10.3329/mh.v1i2.14092 Microbes and Health, 2012 1(2): 62-64

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Characterization of a Deep Sea Bacillus toyonensis Isolate: Genomic and Pathogenic Features

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2021.629116 ◽

2021 ◽

Vol 11 ◽

Author(s):

Jing-chang Luo ◽

Hao Long ◽

Jian Zhang ◽

Yan Zhao ◽

Li Sun

Keyword(s):

Deep Sea ◽

Mammalian Cells ◽

Acute Infection ◽

Genomic Analysis ◽

Comparative Genomic ◽

Circular Chromosome ◽

Isolation And Characterization ◽

High Concentrations ◽

Bacillus Toyonensis

Bacillus toyonensis is a group of Gram-positive bacteria belonging to the Bacillus cereus group and used in some cases as probiotics or biocontrol agents. To our knowledge, B. toyonensis from the deep sea (depth >1,000 m) has not been documented. Here, we report the isolation and characterization of a B. toyonensis strain, P18, from a deep sea hydrothermal field. P18 is aerobic, motile, and able to grow at low temperatures (4°C) and high concentrations of NaCl (8%). P18 possesses a circular chromosome of 5,250,895 bp and a plasmid of 536,892 bp, which encode 5,380 and 523 genes, respectively. Of these genes, 2,229 encode hypothetical proteins that could not be annotated based on the COG database. Comparative genomic analysis showed that P18 is most closely related to the type strain of B. toyonensis, BCT-7112T. Compared to BCT-7112T, P18 contains 1,401 unique genes, 441 of which were classified into 20 COG functional categories, and the remaining 960 genes could not be annotated. A total of 319 putative virulence genes were identified in P18, including toxin-related genes, and 24 of these genes are absent in BCT-7112T. P18 exerted strong cytopathic effects on fish and mammalian cells that led to rapid cell death. When inoculated via injection into fish and mice, P18 rapidly disseminated in host tissues and induced acute infection and mortality. Histopathology revealed varying degrees of tissue lesions in the infected animals. Furthermore, P18 could survive in fish and mouse sera and possessed hemolytic activity. Taken together, these results provide the first evidence that virulent B. toyonensis exists in deep sea environments.

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