44 results on '"Tanya J. Kerr"'
Search Results
2. Comparison of interferon gamma release assay and CXCL9 gene expression assay for the detection of Mycobacterium bovis infection in African lions (Panthera leo)
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Rachiel Gumbo, Tashnica T. Sylvester, Sven D. C. Parsons, Peter E. Buss, Robin M. Warren, Paul D. van Helden, Michele A. Miller, and Tanya J. Kerr
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Microbiology (medical) ,Infectious Diseases ,Immunology ,Microbiology - Abstract
Mycobacterium bovis (M. bovis) infection has been identified in both domestic and wild animals and may threaten the conservation of vulnerable species including African lions (Panthera leo). There is a need to develop accurate ante-mortem tools for detection of M. bovis infection in African big cat populations for wildlife management and disease surveillance. The aim of this study was to compare the performances of two immunological assays, the QuantiFERON®-TB Gold Plus (QFT) Mabtech Cat interferon gamma release assay (IGRA) and QFT CXCL9 gene expression assay (GEA), which have both shown diagnostic potential for M. bovis detection in African lions. Lion whole blood (n=47), stimulated using the QFT platform, was used for measuring antigen-specific CXCL9 expression and IFN-γ production and to assign M. bovis infection status. A subset (n=12) of mycobacterial culture-confirmed M. bovis infected and uninfected African lions was used to compare the agreement between the immunological diagnostic assays. There was no statistical difference between the proportions of test positive African lions tested by the QFT Mabtech Cat IGRA compared to the QFT CXCL9 GEA. There was also a moderate association between immunological diagnostic assays when numerical results were compared. The majority of lions had the same diagnostic outcome using the paired assays. Although the QFT Mabtech Cat IGRA provides a more standardized, commercially available, and cost-effective test compared to QFT CXCL9 GEA, using both assays to categorize M. bovis infection status in lions will increase confidence in results.
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- 2022
3. Identification and Characterisation of Nontuberculous Mycobacteria that may Impede the Diagnosis of Bovine Tuberculosis in African Buffaloes (Syncerus caffer), South Africa
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Charlene Clarke, Tanya J. Kerr, Robin M. Warren, Léanie Kleynhans, Michele Ann Miller, and Wynand Johan Goosen
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molecular_biology - 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 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.
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- 2022
4. Identification and Characterisation of Nontuberculous Mycobacteria in African Buffaloes (
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Charlene, Clarke, Tanya J, Kerr, Robin M, Warren, Léanie, Kleynhans, Michele A, Miller, and Wynand J, Goosen
- Abstract
Diagnosis of bovine tuberculosis (bTB) may be confounded by immunological cross-reactivity to
- Published
- 2022
5. Differential detection of IgM and IgG antibodies to chimeric antigens in bovine tuberculosis
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Archana A. Sridhara, Ashley Johnathan-Lee, Rubyat Elahi, Paul Lambotte, Javan Esfandiari, Maria Laura Boschiroli, Tanya J. Kerr, Michele A. Miller, Thomas Holder, Gareth Jones, H. Martin Vordermeier, Breanne N. Marpe, Tyler C. Thacker, Mitchell V. Palmer, W. Ray Waters, and Konstantin P. Lyashchenko
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General Veterinary ,Immunoglobulin M ,Immunoglobulin G ,Immunology ,Animals ,Cattle Diseases ,Cattle ,Serologic Tests ,Tuberculosis, Bovine ,Mycobacterium bovis - Abstract
Recent studies have suggested the potential of innovative serologic tests for accurate and rapid detection of bovine tuberculosis (bTB). Dual Path Platform (DPP) technology has been used to develop rapid animal-side antibody tests for Mycobacterium bovis infection in a range of livestock and wildlife host species. The present study evaluated diagnostic performance of DPP BovidTB IgM/IgG assay designed for differential detection of bovine IgM and IgG antibodies against two chimeric antigens, DID38 and TBf2, respectively, using 662 well-characterized serum samples from M. bovis-infected and bTB-free cattle collected in the United States, Great Britain, France, and South Africa. Test sensitivity and specificity ranged from 71% to 100% and from 95% to 100%, respectively, depending on the country, with overall accuracy of 83%. No significant risk of cross-reactivity with serum samples from cattle infected with most relevant species of mycobacteria other than M. bovis was found. The DPP BovidTB IgM/IgG assay may be suitable for use in multi-test algorithms to improve current strategies for bTB surveillance.
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- 2022
6. Comparison of interferon gamma release assay and
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Rachiel, Gumbo, Tashnica T, Sylvester, Sven D C, Parsons, Peter E, Buss, Robin M, Warren, Paul D, van Helden, Michele A, Miller, and Tanya J, Kerr
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Lions ,Cats ,Animals ,Gene Expression ,Tuberculosis ,Animals, Wild ,Mycobacterium bovis ,Interferon-gamma Release Tests - Published
- 2022
7. Adaptation and Diagnostic Potential of a Commercial Cat Interferon Gamma Release Assay for the Detection of
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Rachiel, Gumbo, Tashnica T, Sylvester, Wynand J, Goosen, Peter E, Buss, Lin-Mari, de Klerk-Lorist, O Louis, van Schalkwyk, Alicia, McCall, Robin M, Warren, Paul D, van Helden, Michele A, Miller, and Tanya J, Kerr
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- 2022
8. Culture-Independent PCR Detection and Differentiation of Mycobacteria spp. in Antemortem Respiratory Samples from African Elephants (Loxodonta africana) and Rhinoceros (Ceratotherium simum, Diceros bicornis) in South Africa
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Wynand J. Goosen, Charlene C. Clarke, Léanie Kleynhans, Tanya J. Kerr, Peter Buss, and Michele A. Miller
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Microbiology (medical) ,African elephants ,bronchioloalveolar lavage ,GeneXpert MTB/RIF Ultra ,Hain CMdirect V1.0 LPA ,ku PCR ,mycobacterium tuberculosis complex ,non-tuberculous mycobacteria ,rhinoceros ,rpoB PCR ,trunk wash ,Infectious Diseases ,General Immunology and Microbiology ,veterinary_medicine ,Immunology and Allergy ,bacterial infections and mycoses ,Molecular Biology - Abstract
Since certain Mycobacterium tuberculosis complex (MTBC) members, such as M. bovis, are endemic in specific South African wildlife reserves and zoos, cases of clinically important nontuberculous mycobacteria (NTM) in wildlife may be neglected. Additionally, due to the inability of tests to differentiate between the host responses to MTBC and NTM, the diagnosis of MTBC may be confounded by the presence of NTMs. This may hinder control efforts. These constraints highlight the need for enhanced rapid detection and differentiation methods for MTBC and NTM, especially in high MTBC burden areas. We evaluated the use of the GeneXpert MTB/RIF Ultra, the Hain CMdirect V1.0 line probe assay, and novel amplicon sequencing PCRs targeting the mycobacterial rpoB and ku gene targets, directly on antemortem African elephant (n = 26) bronchoalveolar lavage fluid (BALF) (n = 22) and trunk washes (n = 21) and rhinoceros (n = 23) BALF (n = 23), with known MTBC culture-positive and NTM culture-positive results. Our findings suggest that the Ultra is the most sensitive diagnostic test for MTBC DNA detection directly in raw antemortem respiratory specimens and that the rpoB PCR is ideal for Mycobacterium genus DNA detection and species identification through amplicon sequencing.
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- 2022
9. Culture-Independent PCR Detection and Differentiation of
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Wynand J, Goosen, Charlene, Clarke, Léanie, Kleynhans, Tanya J, Kerr, Peter, Buss, and Michele A, Miller
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Since certain
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- 2022
10. Novel molecular transport medium used in combination with Xpert MTB/RIF ultra provides rapid detection of Mycobacterium bovis in African buffaloes
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Katrin Smith, Tanya J. Kerr, Robin M. Warren, Michele A. Miller, David Cooper, Charlene Clarke, Samantha Goldswain, Léanie Kleynhans, Christopher Helm, Paul D. van Helden, and Wynand J. Goosen
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0301 basic medicine ,Buffaloes ,Molecular biology ,Science ,030106 microbiology ,Sample processing ,Negative control ,Rapid detection ,Article ,Microbiology ,03 medical and health sciences ,Molecular Transport ,Bovine tuberculosis ,Animals ,Tuberculosis ,Mycobacterium bovis ,Multidisciplinary ,biology ,Mycobacterial culture ,Translational research ,biology.organism_classification ,030104 developmental biology ,Mycobacterium tuberculosis complex ,Medicine - Abstract
Mycobacterium bovis is the causative agent of bovine tuberculosis (bTB) in wildlife. Confirmation of M. bovis infection relies on mycobacterial culture, which is time-consuming. Collection and transportation of infectious material also pose a human health risk. PrimeStore Molecular Transport Medium (MTM) has been shown to effectively inactivate infectious organisms, making it a safe method for handling infectious samples. This study investigated an in-field sampling technique for rapid, safe detection of M. bovis in buffalo tissues. Potentially infected tissues from bTB test-positive buffaloes were swabbed at post-mortem examination and stored in PrimeStore MTM at ambient temperature until Xpert MTB/RIF Ultra testing was performed. Additionally, tissue samples were frozen and transported before homogenisation for culture and Ultra testing. Oral swabs were collected from M. bovis-unexposed buffaloes as a negative control cohort. Mycobacterium tuberculosis complex (MTBC) DNA was detected by Ultra in 13/16 tissue swabs and 9/16 matched tissue homogenates from culture-confirmed M. bovis-positive buffalo tissues. MTBC DNA was not detected in swabs from M. bovis-unexposed animals, showing the potentially high specificity of Ultra with PrimeStore swabs. PrimeStore MTM sample processing, in combination with the Ultra assay, has the potential to provide a safe, rapid post-mortem screening test for M. bovis in buffaloes.
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- 2021
11. Diagnosis of Mycobacterium bovis infection in free‐ranging common hippopotamus ( Hippopotamus amphibius )
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Tanya J. Kerr, Robin M. Warren, Oonagh Pretorius, Konstantin P. Lyashchenko, Peter Buss, Paul D. van Helden, Lin-Mari de Klerk-Lorist, Michele A. Miller, Wynand J. Goosen, Léanie Kleynhans, and Rachiel Gumbo
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Mycobacterium bovis ,General Veterinary ,General Immunology and Microbiology ,biology ,Free ranging ,Wildlife ,Cattle Diseases ,Zoology ,General Medicine ,biology.organism_classification ,Hippopotamus amphibius ,Serology ,Interspecies transmission ,Seroepidemiologic Studies ,biology.animal ,Hippopotamus ,Animals ,Tuberculosis ,Seroprevalence ,Cattle ,Tuberculosis, Bovine ,Ecosystem ,Artiodactyla ,Retrospective Studies - Abstract
Bovine tuberculosis (bTB), caused by Mycobacterium bovis (M. bovis) infection, is a multi-host disease which negatively affects the wildlife industry, with adverse consequences for conservation, ecotourism, and game/wildlife sales. Although interspecies transmission has been reported between some wildlife hosts, the risk of spread in complex ecosystems is largely unknown. As a controlled disease, tools for accurate detection of M. bovis infection are crucial for effective surveillance and management, especially in wildlife populations. There are, however, limited species-specific diagnostic tests available for wildlife. Hippopotamuses are rarely tested for M. bovis infection, and infection has not previously been confirmed in these species. In this study, blood and tissue samples collected from common hippopotamus (Hippopotamus amphibius) residing in a bTB-endemic area, the Greater Kruger Protected area (GKPA), were retrospectively screened to determine whether there was evidence for interspecies transmission of M. bovis, and identify tools for M. bovis detection in this species. Using the multi-species DPP® VetTB serological assay, a bTB seroprevalence of 8% was found in hippopotamus from GKPA. In addition, the first confirmed case of M. bovis infection in a free-ranging common hippopotamus is reported, based on the isolation in mycobacterial culture, genetic speciation and detection of DNA in tissue samples. Importantly, the M. bovis spoligotype (SB0121) isolated from this common hippopotamus is shared with other M. bovis-infected hosts in GKPA, suggesting interspecies transmission. These results support the hypothesis that M. bovis infection may be under recognized in hippopotamus. Further investigation is needed to determine the risk of interspecies transmission of M. bovis to common hippopotamus in bTB-endemic ecosystems and evaluate serological and other diagnostic tools in this species.
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- 2021
12. DETECTION OF ELEPHANT ENDOTHELIOTROPIC HERPESVIRUS (EEHV) IN FREE-RANGING AFRICAN ELEPHANTS (LOXODONTA AFRICANA) IN THE KRUGER NATIONAL PARK, SOUTH AFRICA
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Tanya J. Kerr, Jana van Heerden, Wynand J. Goosen, Léanie Kleynhans, Peter E. Buss, Erin Latimer, and Michele A. Miller
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Ecology ,Ecology, Evolution, Behavior and Systematics - Abstract
Elephant endotheliotropic herpesvirus (EEHV) infection can cause acute, often fatal, EEHV hemorrhagic disease in free-ranging and human-managed Asian elephants (Elephas maximus) and human-managed African elephants (Loxodonta africana). However, significant knowledge gaps exist pertaining to the presence of EEHV in free-ranging African elephant populations. We retrospectively screened 142 opportunistically collected samples (blood, n=98; bronchoalveolar lavage (BAL) fluid, n=21; trunk wash (TW) fluid, n=23) obtained between 2010 and 2020 from 98 free-ranging African elephants in the Kruger National Park, South Africa, for the presence of different EEHVs, as well as determining the real-time quantitative PCR positivity rate in this population. With the use of validated, previously published DNA extraction and real-time quantitative PCR protocols provided by the National Elephant Herpesvirus Laboratory (Washington, DC, USA), EEHV was detected in nine male African elephants from samples collected in 2011 (n=1), 2013 (n=1), 2018 (n=2), 2019 (n=4), and 2020 (n=1). Viral detection was more common in respiratory compared with blood samples. Six elephants tested positive for EEHV2 subtype (blood, n=2; BAL, n=3; TW, n=2), including one individual that tested positive on matched respiratory samples (BAL and TW). Four elephants tested positive for EEHV3-4-7 (blood, n=1; BAL, n=2; TW, n=1), whereas EEHV6 was not detected in any of the study animals. One elephant tested positive for both EEHV2 and EEHV3-4-7 in the same BAL sample. Even though the levels of viremia varied between 158 and 1,292 viral genome equivalents/mL blood and viral shedding of EEHV2 and EEHV3-4-7 was detected in respiratory samples, no clinical signs were observed in these apparently healthy elephants. These findings are consistent with reports of asymptomatic EEHV infection in human-managed African elephants.
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- 2022
13. CYTOKINE-RELEASE ASSAY FOR THE DETECTION OF MYCOBACTERIUM BOVIS INFECTION IN CHEETAH (ACINONYX JUBATUS)
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Rachiel Gumbo, Elin Crockett, Wynand J. Goosen, Robin M. Warren, Paul D. van Helden, Michele A. Miller, and Tanya J. Kerr
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General Veterinary ,Animal Science and Zoology ,General Medicine - Published
- 2021
14. CYTOKINE-RELEASE ASSAY FOR THE DETECTION OF
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Rachiel, Gumbo, Elin, Crockett, Wynand J, Goosen, Robin M, Warren, Paul D, van Helden, Michele A, Miller, and Tanya J, Kerr
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Cats ,Animals ,Cytokines ,Tuberculosis ,Acinonyx ,Cat Diseases ,Mycobacterium bovis ,Interferon-gamma Release Tests - Abstract
The lack of species-specific assays for the diagnosis of infectious diseases, such as bovine tuberculosis, poses a threat to the management of wildlife populations, especially for vulnerable species such as cheetah (
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- 2021
15. Improved detection of
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Wynand J, Goosen, Léanie, Kleynhans, Tanya J, Kerr, Paul D, van Helden, Peter, Buss, Robin M, Warren, and Michele A, Miller
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South Africa ,Dietary Supplements ,African wildlife ,Mycobacterium tuberculosis complex ,Animals ,Animals, Wild ,Mycobacterium tuberculosis ,Full Scientific Reports ,Peptides ,Mycobacterium bovis ,TiKa ,Decontamination ,culture - Abstract
In South Africa, mycobacterial culture is regarded as the gold standard for the detection of Mycobacterium tuberculosis complex (MTBC) infection in wildlife even though it is regarded as “imperfect.” We compared a novel decontamination and mycobacterial culture technique (TiKa) to the conventional mycobacterium growth indicator tube (MGIT) system using known amounts of bacilli and clinical samples from MTBC-infected African buffaloes (Syncerus caffer), white rhinoceros (Ceratotherium simum), and African elephants (Loxodonta africana). Use of the TiKa-KiC decontamination agent on samples spiked with 10,000 to 10 colony forming units (cfu) of M. bovis (SB0121) and M. tuberculosis (H37Rv) had no effect on isolate recovery in culture. In contrast, decontamination with MGIT MycoPrep resulted in no growth of M. bovis samples at concentrations
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- 2021
16. The Seroepidemiology of a Neglected Zoonotic and Livestock Pathogen in Free-Ranging Bovids: Leptospirosis in African Buffaloes (Syncerus caffer)
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Tanya J. Kerr, Wynand J. Goosen, Michele A. Miller, Andrew Potts, and Mark Moseley
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Microbiology (medical) ,Serotype ,Veterinary medicine ,spillover ,animal diseases ,Biology ,Leptospira ,parasitic diseases ,medicine ,disease ecology ,Immunology and Allergy ,Seroprevalence ,leptospirosis ,One Health ,Molecular Biology ,General Immunology and Microbiology ,Zoonotic Infection ,business.industry ,Zoonosis ,Microscopic Agglutination Typing ,zoonosis ,medicine.disease ,biology.organism_classification ,Leptospirosis ,Africa ,Infectious Diseases ,Herd ,Medicine ,Livestock ,business - Abstract
Multi-host pathogens are challenging to control and are responsible for some of the most important diseases of humans, livestock, and wildlife. Leptospira spp. are some of the most common multi-host pathogens and represent an important cause of zoonotic infections and livestock productivity loss in the developing world, where contact with wildlife species is common. Although there is increasing evidence that cattle in Africa harbour a broad diversity of Leptospira genotypes and serovars, little is known about the epidemiology of these pathogens in wild bovids, such as African buffaloes (Syncerus caffer). Using microscopic agglutination testing (MAT) on serum samples collected from free-ranging buffaloes (n = 98) captured in the Hluhluwe-iMfolozi Park (HiP), South Africa, we demonstrated an overall seroprevalence of 21% with seropositivity almost exclusively limited to serovar Tarassovi (serogroup Tarassovi). Moreover, we found no evidence of seropositivity in unweaned calves and showed temporal- or herd-specific variation in exposure risk, and increased probability of seropositivity (OR = 5.44, 95% CI = 1.4–27) in female buffaloes. Together, these findings demonstrate that free-ranging African buffaloes are exposed to Leptospira spp. infections, providing insights into the epidemiology of an emerging Leptospira serovar in herds with an absence of any disease control and minimal management.
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- 2021
17. Mycobacterium bovis Infection in Free-Ranging African Elephants
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Louis van Schalkwyk, Wynand J. Goosen, Michele A. Miller, Tebogo Manamela, Léanie Kleynhans, Candice R. de Waal, Paul D. van Helden, Robin M. Warren, Elizabeth M. Streicher, Peter Buss, Guy Hausler, Tanya J. Kerr, and Leana Rossouw
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Microbiology (medical) ,Epidemiology ,Elephants ,Wildlife ,Zoology ,lcsh:Medicine ,Animals, Wild ,Loxodonta africana ,Biology ,lcsh:Infectious and parasitic diseases ,African elephant ,South Africa ,biology.animal ,Bovine tuberculosis ,Research Letter ,Animals ,Tuberculosis ,lcsh:RC109-216 ,bacteria ,Mycobacterium bovis ,Free ranging ,endemic bovine tuberculosis ,National park ,Captive elephants ,lcsh:R ,biology.organism_classification ,tuberculosis and other mycobacteria ,Mycobacterium bovis Infection in Free-Ranging African Elephants ,Infectious Diseases ,Kruger National Park ,GeneXpert Ultra - Abstract
Mycobacterium bovis infection in wildlife species occurs worldwide. However, few cases of M. bovis infection in captive elephants have been reported. We describe 2 incidental cases of bovine tuberculosis in free-ranging African elephants (Loxodonta africana) from a tuberculosis-endemic national park in South Africa and the epidemiologic implications of these infections.
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- 2021
18. Identification and Characterisation of Nontuberculous Mycobacteria in African Buffaloes (Syncerus caffer), South Africa
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Charlene Clarke, Tanya J. Kerr, Robin M. Warren, Léanie Kleynhans, Michele A. Miller, and Wynand J. Goosen
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Microbiology (medical) ,African buffaloes ,bovine tuberculosis ,cfp-10 ,esat-6 ,hsp65 ,nontuberculous mycobacteria ,rpoB ,Syncerus caffer ,Virology ,Microbiology - 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 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.
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- 2022
19. SEROLOGICAL EVIDENCE OF COXIELLA BURNETII INFECTION IN THE WHITE RHINOCEROS (CERATOTHERIUM SIMUM) IN SOUTH AFRICA
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Kyle A. Donnelly, Tanya J. Kerr, Charles Van Niekerk, Scott B. Citino, Peter Buss, Léanie Kleynhans, Michele A. Miller, and Douw Grobler
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medicine.medical_specialty ,Veterinary medicine ,General Veterinary ,biology ,National park ,Ceratotherium simum ,Public health ,Antibody titer ,Rhinoceros ,General Medicine ,Abortion ,Coxiella burnetii ,biology.organism_classification ,Herd ,medicine ,Animal Science and Zoology - Abstract
Coxiellosis, or Query (Q) fever, a disease caused by the intracellular bacteria Coxiella burnetii, was recently described in a managed breeding herd of white rhinoceros (Ceratotherium simum) in the southeastern United States. Clinical disease often results in abortion and could represent a conservation challenge for this species. In addition to the reproductive and herd management consequences, coxiellosis is also a zoonotic disease. Infection or clinical disease in any free-ranging rhinoceros species in a national park setting has not been previously described. In this study, evidence of prior infection was measured by immunofluorescent antibody titers in 89 serum samples collected from white rhinoceros within private reserves and a national park in South Africa. Total seropositivity was 48/89 (53.9% [95% CI, 43.6-63.9%]). Animals on private reserves had a seropositivity of 21/51 (41.1% [95% CI, 27.1-55.2%]), and national park rhinoceros had a higher rate of seropositivity at 71.0% [95% CI, 55.9-86.2%] (27/38; P= 0.004). Adults had a higher seropositivity compared with subadults (P= 0.03). There was no difference in seropositivity between sexes (P > 0.05). Results demonstrate that South African white rhinoceros populations are exposed to Coxiella, which could result in underrecognized reproductive consequences. Further studies should investigate potential implications for public health and conservation management of this species.
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- 2021
20. Adaptation and Diagnostic Potential of a Commercial Cat Interferon Gamma Release Assay for the Detection of Mycobacterium bovis Infection in African Lions (Panthera leo)
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Rachiel Gumbo, Tashnica T. Sylvester, Wynand J. Goosen, Peter E. Buss, Lin-Mari de Klerk-Lorist, O. Louis van Schalkwyk, Alicia McCall, Robin M. Warren, Paul D. van Helden, Michele A. Miller, and Tanya J. Kerr
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Microbiology (medical) ,Infectious Diseases ,General Immunology and Microbiology ,African lion ,bovine tuberculosis ,cytokine ELISA ,IFN-γ ,interferon-gamma release assay ,Mycobacterium bovis ,Panthera leo ,Immunology and Allergy ,Molecular Biology - Abstract
Mycobacterium bovis (M. bovis) infection in wildlife, including lions (Panthera leo), has implications for individual and population health. Tools for the detection of infected lions are needed for diagnosis and disease surveillance. This study aimed to evaluate the Mabtech Cat interferon gamma (IFN-γ) ELISABasic kit for detection of native lion IFN-γ in whole blood samples stimulated using the QuantiFERON® TB Gold Plus (QFT) platform as a potential diagnostic assay. The ELISA was able to detect lion IFN-γ in mitogen-stimulated samples, with good parallelism, linearity, and a working range of 15.6–500 pg/mL. Minimal matrix interference was observed in the recovery of domestic cat rIFN-γ in lion plasma. Both intra- and inter-assay reproducibility had a coefficient of variation less than 10%, while the limit of detection and quantification were 7.8 pg/mL and 31.2 pg/mL, respectively. The diagnostic performance of the QFT Mabtech Cat interferon gamma release assay (IGRA) was determined using mycobacterial antigen-stimulated samples from M. bovis culture-confirmed infected (n = 8) and uninfected (n = 4) lions. A lion-specific cut-off value (33 pg/mL) was calculated, and the sensitivity and specificity were determined to be 87.5% and 100%, respectively. Although additional samples should be tested, the QFT Mabtech Cat IGRA could identify M. bovis-infected African lions.
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- 2022
21. SEROLOGICAL EVIDENCE OF
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Kyle A, Donnelly, Michele A, Miller, Douw, Grobler, Peter, Buss, Charles, Van Niekerk, Léanie, Kleynhans, Tanya J, Kerr, and Scott B, Citino
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Male ,South Africa ,Coxiella burnetii ,Animals ,Female ,Q Fever ,Antibodies, Bacterial ,Perissodactyla - Abstract
Coxiellosis, or Query (Q) fever, a disease caused by the intracellular bacteria
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- 2021
22. Evaluating residual compressive strength of post-fire concrete using Raman Spectroscopy
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Jose Gonzalez-Rodriguez, Tanya J. Kerr, and Marleen Vetter
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Cement ,Materials science ,Thermal decomposition ,Residual ,Pathology and Forensic Medicine ,Matrix (geology) ,symbols.namesake ,chemistry.chemical_compound ,Compressive strength ,chemistry ,Phase (matter) ,symbols ,Composite material ,Calcium silicate hydrate ,Raman spectroscopy ,Law - Abstract
Cement and water within the concrete mass create a hydrated phase which acts as the glue for holding the sand and coarse aggregates in place to develop a strong construction material. The most important phase within the cement matrix is that of calcium silicate hydrate (CSH), which is largely responsible for the concrete strength. Decomposition of the CSH phase due to high temperatures will affect compressive strength of the concrete. Raman bands at 1083, 709 and 276 cm−1, which are representative of the CaCO3 and CSH presence in the concrete matrix phases can be used to assess changes in compressive strength as a result of thermal decomposition. The ratio between 1083/709 cm−1 bands was calculated and correlated to the compression strength of the concrete. The results show there is a rapid decline in strength around a critical peak ratio of 8.78 and a residual compressive strength of 0.62, closely following a polynomial curve. The tool developed here allows an indirect evaluation of the temperature the concrete has been exposed to by studying the band. A case study from a fire scene taken from a warehouse in Kingston (Jamaica) is also presented with the conclusion and results compared. The study showed that Raman spectroscopy has the potential to provide in-situ non-destructive testing of fire damaged concrete rapidly and accurately.
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- 2021
23. Use of PrimeStore® Molecular Transport Medium and Xpert MTB/RIF Ultra for Rapid Detection of Mycobacterium Bovis in African buffaloes (Syncerus Caffer)
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Tanya J. Kerr, Michele A. Miller, Charlene Clarke, Samantha Goldswain, Katrin Smith, Paul D. van Helden, Wynand J. Goosen, Christopher Helm, Robin M. Warren, David Cooper, and Léanie Kleynhans
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Mycobacterium bovis ,biology ,Molecular Transport ,biology.organism_classification ,Rapid detection ,Microbiology - Abstract
Mycobacterium bovis is the causative agent of bovine tuberculosis (bTB) in wildlife. Confirmation of M. bovis infection relies on mycobacterial culture, which is time-consuming. Collection and transportation of infectious material also pose a human health risk. PrimeStore® Molecular Transport Medium (MTM) has been shown to effectively inactivate infectious organisms, making it a safe method for handling infectious samples. This study investigated an in-field sampling technique for rapid, safe detection of M. bovis in buffalo tissues. Potentially infected tissues from bTB test-positive buffaloes were swabbed at post-mortem examination and stored in PrimeStore® MTM at ambient temperature until Xpert® MTB/RIF Ultra testing was performed. Additionally, tissue samples were frozen and transported before homogenisation for culture and Ultra testing. Oral swabs were collected from M. bovis-unexposed buffaloes as a negative control cohort. Mycobacterium tuberculosis complex (MTBC) DNA was detected by Ultra in 13/16 tissue swabs and 9/16 matched tissue homogenates from culture-confirmed M. bovis-positive buffalo tissues. MTBC DNA was not detected in swabs from M. bovis-unexposed animals, showing the potentially high specificity of Ultra with PrimeStore® swabs. PrimeStore® MTM sample processing, in combination with the Ultra assay, has the potential to provide a safe, rapid post-mortem screening test for M. bovis in buffaloes.
- Published
- 2021
24. Development of a cytokine gene expression assay for the relative quantification of the African elephant (Loxodonta africana) cell-mediated immune responses
- Author
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Robin M. Warren, Paul D. van Helden, Jennifer A. Landolfi, Candice R. de Waal, Michele A. Miller, Sven D.C. Parsons, Peter Buss, Tanya J. Kerr, Guy Hausler, Wynand J. Goosen, and Léanie Kleynhans
- Subjects
0301 basic medicine ,medicine.medical_treatment ,Immunology ,Elephants ,Biology ,Biochemistry ,African elephant ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,biology.animal ,medicine ,Immunology and Allergy ,Animals ,Cytokine genes ,Molecular Biology ,Whole blood ,Immunoassay ,Pokeweed mitogen ,Hematology ,Interleukin 10 ,030104 developmental biology ,Cytokine ,Gene Expression Regulation ,030220 oncology & carcinogenesis ,Cytokines ,Tumor necrosis factor alpha - Abstract
Immunological assays are the basis for many diagnostic tests for infectious diseases in animals and humans. Application in wildlife species, including the African elephant (Loxodonta africana), is limited however due to lack of information on immune responses. Since many immunoassays require both identified biomarkers of immune activation as well as species-specific reagents, it is crucial to have knowledge of basic immunological responses in the species of interest. Cytokine gene expression assays (GEAs) used to measure specific immune responses in wildlife have frequently shown that targeted biomarkers are often species-specific. Therefore, the aim of this study was to identify elephant-specific cytokine biomarkers to detect immune activation and to develop a GEA, using pokeweed mitogen stimulated whole blood from African elephants. This assay will provide the foundation for the development of future cytokine GEAs that can be used to detect antigen specific immune responses and potentially lead to various diagnostic tests for this species.
- Published
- 2020
25. Use of blood matrices and alternative biological fluids for antibody detection in animal tuberculosis
- Author
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Rubyat Elahi, Tanya J. Kerr, Alina Sikar-Gang, Mitchell V. Palmer, Konstantin P. Lyashchenko, Javan Esfandiari, Eduard O. Roos, W. Ray Waters, Paul Lambotte, Michele A. Miller, Archana A. Sridhara, Tyler C. Thacker, Ashley Johnathan-Lee, and Rena Greenwald
- Subjects
Saliva ,Swine ,Immunology ,Immunologic Tests ,Serology ,Antigen ,medicine ,Animals ,Whole blood ,Swine Diseases ,Mycobacterium bovis ,General Veterinary ,biology ,medicine.diagnostic_test ,Plant Extracts ,biology.organism_classification ,Antibodies, Bacterial ,Immunoassay ,Immunoglobulin G ,biology.protein ,Cattle ,Lymph ,Antibody ,Tuberculosis, Bovine - Abstract
Bovine tuberculosis (bTB) control programs can be improved by implementation of advanced ante-mortem testing algorithms. Serodiagnostic methods using traditional blood or blood-derived specimens may benefit from the use of less invasive alternative biological fluids, provided those mirror systemic antibody responses. In the present study, we used Dual Path Platform (DPP) and Multiantigen Print Immunoassay (MAPIA) to compare antibody levels in ten sample types including whole blood (fresh and hemolyzed), plasma (fresh and leftover from Bovigam testing), serum, saliva, broncho-alveolar lavage, urine, diaphragm extract, and bile collected from cattle aerosol-infected with Mycobacterium bovis. High correlation (r = 0.97-0.99) in measurements of IgG antibodies to MPB70/MPB83 fusion antigen by DPP assay was found between all blood-derived specimens, supporting matrix equivalency. Broncho-alveolar lavage and diaphragm extract yielded positive results in all the infected animals tested, showing high correlation with matching serum data (r = 0.94 and r = 0.95, respectively) and suggesting their potential use in antibody assays. Characterized by MAPIA, the antigen reactivity patterns obtained with paired sera and alternative specimens were nearly identical, with slight differences in intensity. Antibodies were also found by DPP assay in saliva, urine, and bile from some of the infected animals, but the titers were relatively low, thus reducing the diagnostic value of such specimens. The proposed approach was evaluated in a pilot field study on warthogs diagnosed with M. bovis infection. Relative levels of antibody in tissue fluid obtained from lymph nodes or lungs were consistent with those detected in sera and detectable in all infected warthogs. The findings support the diagnostic utility of non-traditional biological fluids and tissue samples when used as alternative test specimens in serologic assays for bTB.
- Published
- 2020
26. Optimisation of the tuberculin skin test for detection of Mycobacterium bovis in African buffaloes (Syncerus caffer)
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Alicia J. McCall, Charlene Clarke, Warren A. McCall, Candice R. de Waal, Tanya J. Kerr, Katrin Smith, Sven D.C. Parsons, David Cooper, Emma Rambert, Robin M. Warren, Debbie Cooke, Léanie Kleynhans, Samantha Goldswain, Michele A. Miller, Netanya Bernitz, Wynand J. Goosen, and Paul D. van Helden
- Subjects
Veterinary medicine ,Buffaloes ,040301 veterinary sciences ,030231 tropical medicine ,Tuberculin ,0403 veterinary science ,03 medical and health sciences ,South Africa ,0302 clinical medicine ,Food Animals ,Screening method ,Bovine tuberculosis ,Medicine ,Animals ,Tuberculosis ,Tuberculin test ,Mycobacterium bovis ,biology ,Comparative test ,business.industry ,Tuberculin Test ,04 agricultural and veterinary sciences ,Skin test ,biology.organism_classification ,Animal Science and Zoology ,business - Abstract
Effective screening methods are critical for preventing the spread of bovine tuberculosis (bTB) among livestock and wildlife species. The tuberculin skin test (TST) remains the primary test for bTB globally, although performance is suboptimal. African buffaloes (Syncerus caffer) are a maintenance host of Mycobacterium bovis in South Africa, tested using the single intradermal tuberculin test (SITT) or comparative test (SICTT). The interpretation of these tests has been based on cattle thresholds due to the lack of species-specific cut-off values for African buffaloes. Therefore, the aims of this study were to calculate buffalo-specific thresholds for different TST criteria (SITT, SICTT, and SICTT72h that calculates the differential change at 72 h only) and compare performance using these cut-off values. The results confirm that 3 mm best discriminates M. bovis-infected from unexposed control buffaloes with sensitivities of 69 % (95 % CI 60-78; SITT and SICTT) and 76 % (95 % CI 65-83; SICTT72h), and specificities of 86 % (95 % CI 80-90; SITT), 96 % (95 % CI 92-98; SICTT72h) and 97 % (95 % CI 93-99; SICTT), respectively. A comparison between TST criteria using buffalo-specific thresholds demonstrates that the comparative TST performs better than the SITT, although sensitivity remains suboptimal. Therefore, further research and the addition of ancillary tests, such as cytokine release assays, are necessary to improve M. bovis detection in African buffaloes.
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- 2020
27. Review of Diagnostic Tests for Detection of
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Konstantin P. Lyashchenko, Sven D.C. Parsons, Charlene Clarke, Katrin Smith, Robin M. Warren, Michele A. Miller, Taschnica T Sylvester, David Cooper, Candice R. de Waal, Anzaan Dippenaar, Wynand J. Goosen, Christina Meiring, Paul D. van Helden, Léanie Kleynhans, Tanya J. Kerr, Peter Buss, Samantha Goldswain, Rachiel Gumbo, Eduard O. Roos, Netanya Bernitz, Roxanne L. Higgitt, and Josephine Chileshe
- Subjects
0301 basic medicine ,Tuberculosis ,040301 veterinary sciences ,Wildlife ,Zoology ,Review ,Disease ,immunological assays ,direct detection of mycobacteria ,0403 veterinary science ,03 medical and health sciences ,diagnostics ,Bovine tuberculosis ,medicine ,South African wildlife ,bovine tuberculosis ,Mycobacterium bovis ,gene expression assays ,lcsh:Veterinary medicine ,biology ,General Veterinary ,business.industry ,Diagnostic test ,04 agricultural and veterinary sciences ,medicine.disease ,biology.organism_classification ,cytokine release assays ,030104 developmental biology ,lcsh:SF600-1100 ,Veterinary Science ,Livestock ,Identification (biology) ,business - Abstract
Wildlife tuberculosis is a major economic and conservation concern globally. Bovine tuberculosis (bTB), caused byMycobacterium bovis(M. bovis), is the most common form of wildlife tuberculosis. In South Africa, to date,M. bovisinfection has been detected in 24 mammalian wildlife species. The identification ofM. bovisinfection in wildlife species is essential to limit the spread and to control the disease in these populations, sympatric wildlife species and neighboring livestock. The detection ofM. bovis-infected individuals is challenging as only severely diseased animals show clinical disease manifestations and diagnostic tools to identify infection are limited. The emergence of novel reagents and technologies to identifyM. bovisinfection in wildlife species are instrumental in improving the diagnosis and control of bTB. This review provides an update on the diagnostic tools to detectM. bovisinfection in South African wildlife but may be a useful guide for other wildlife species.
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- 2020
28. Implications of Interspecies Transmission and Diagnosis of Mycobacterium bovis Infection in Free-Ranging Common Hippopotamus (Hippopotamus amphibius)
- Author
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Paul D. van Helden, Léanie Kleynhans, Michele A. Miller, Peter Buss, Oonagh Pretorius, Tanya J. Kerr, Wynand J. Goosen, Robin M. Warren, Rachiel Gumbo, Lin-Mari deKlerk-Lorist, and Konstantin P. Lyashchenko
- Subjects
Interspecies transmission ,Mycobacterium bovis ,biology ,Free ranging ,biology.animal ,Hippopotamus ,Wildlife ,Zoology ,Diagnostic tools ,biology.organism_classification ,Hippopotamus amphibius ,Serology - Abstract
Bovine tuberculosis (bTB), caused by Mycobacterium bovis (M. bovis) infection, is a multi-host disease which negatively affects the wildlife industry, with adverse consequences for conservation, ecotourism, and game/wildlife sales. Although interspecies transmission has been reported between some wildlife hosts, the risk of spread in complex ecosystems is largely unknown. As a controlled disease, tools for accurate detection of M. bovis infection is crucial for effective surveillance and management, especially in wildlife populations. There are however, limited species-specific diagnostic tests available for wildlife. Hippopotamuses are rarely tested for M. bovis infection and infection has not previously been confirmed in these species. In this study, blood and tissue samples collected from common hippopotamus (Hippopotamus amphibius) residing in a bTB endemic area, the Greater Kruger Protected area (GKPA), were retrospectively screened to determine whether there was evidence for interspecies transmission of M. bovis, and to identify tools for M. bovis detection in this species. Using the multi-species DPP® VetTB serological assay, a bTB seroprevelance of 8% was found in hippopotamus from GKPA. In addition, the first confirmed case of M. bovis infection in a free-ranging common hippopotamus is reported, based on the isolation in mycobacterial culture, genetic speciation, and detection of DNA in tissue samples. Importantly, the M. bovis spoligotype (SB0121) isolated from this common hippopotamus is shared with other M. bovis-infected hosts in GKPA, suggesting interspecies transmission. These results support the hypothesis that M. bovis infection may be under recognized in hippopotamus. Further investigation is needed to determine the risk of interspecies transmission of M. bovis to common hippopotamus in bTB endemic ecosystems and evaluate serological and other diagnostic tools in this species.
- Published
- 2020
29. Cytokine biomarker discovery in the white rhinoceros (Ceratotherium simum)
- Author
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Robin M. Warren, Tanya J. Kerr, Paul D. van Helden, Peter Buss, Sven D.C. Parsons, Michele A. Miller, Josephine Chileshe, and Craig J. Kinnear
- Subjects
040301 veterinary sciences ,Immunology ,Rhinoceros ,Pilot Projects ,Real-Time Polymerase Chain Reaction ,0403 veterinary science ,03 medical and health sciences ,Immune system ,Antigen ,Gene expression ,medicine ,Animals ,Tuberculosis ,Interferon gamma ,Biomarker discovery ,Perissodactyla ,030304 developmental biology ,0303 health sciences ,Mycobacterium bovis ,General Veterinary ,biology ,Ceratotherium simum ,Gene Expression Profiling ,04 agricultural and veterinary sciences ,Sequence Analysis, DNA ,biology.organism_classification ,Virology ,Cytokines ,Biomarkers ,medicine.drug - Abstract
Bovine tuberculosis (bTB), caused by Mycobacterium bovis (M. bovis) infection, disrupts conservation programs of threatened species such as the white rhinoceros (Ceratotherium simum). Interferon gamma release assays have been developed for the diagnosis of M. bovis infection in rhinoceros, however, the discovery of additional diagnostic biomarkers might improve the accuracy of case detection. The aim of this pilot study was therefore to evaluate a novel unbiased approach to candidate biomarker discovery and preliminary validation. Whole blood samples from twelve white rhinoceros were incubated in Nil and TB antigen tubes of the QuantiFERON® TB Gold (In-Tube) system after which RNA was extracted and reverse transcribed. Using the equine RT2 profiler PCR array, relative gene expression analysis of samples from two immune sensitized rhinoceros identified CCL4, CCL8, IL23A, LTA, NODAL, TNF, CSF3, CXCL10 and GPI as upregulated in response to antigen stimulation. Novel gene expression assays (GEAs) were designed for selected candidates, i.e. CCL4, CXCL10 and IFNG, and analysis of QFT-processed samples showed the CXCL10 GEA could distinguish between five M. bovis-infected and five uninfected rhinoceros. These findings confirm the value of the equine RT2 profiler PCR array as a useful tool for screening biomarkers for the diagnosis of M. bovis infection in rhinoceros.
- Published
- 2020
30. The VetMAXTM M. tuberculosis Complex PCR Kit detects MTBC DNA in antemortem and postmortem samples from white rhinoceros (Ceratotherium simum), African elephants (Loxodonta africana) and African buffaloes (Syncerus caffer)
- Author
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Wynand J. Goosen, Tanya J. Kerr, Bjorn Schroder, Sven D.C. Parsons, Michele A. Miller, Peter Buss, Paul D. van Helden, David Cooper, Léanie Kleynhans, and Robin M. Warren
- Subjects
Tuberculosis ,Buffaloes ,Elephants ,Rhinoceros ,Real-Time Polymerase Chain Reaction ,law.invention ,Mycobacterium tuberculosis ,chemistry.chemical_compound ,African buffaloes ,law ,medicine ,Animals ,Polymerase chain reaction ,Perissodactyla ,Mycobacterium bovis ,lcsh:Veterinary medicine ,General Veterinary ,biology ,Ceratotherium simum ,Methodology Article ,African elephants ,General Medicine ,VetMAX™ MTBC detection kit qPCR, white rhinoceros ,DNA ,biology.organism_classification ,medicine.disease ,Virology ,PCR ,Mycobacterium tuberculosis complex ,chemistry ,lcsh:SF600-1100 - Abstract
Background Bovine tuberculosis and tuberculosis are chronic infectious diseases caused by the Mycobacterium tuberculosis complex members, Mycobacterium bovis and Mycobacterium tuberculosis, respectively. Infection with M. bovis and M. tuberculosis have significant implications for wildlife species management, public health, veterinary disease control, and conservation endeavours. Results Here we describe the first use of the VetMAX™ Mycobacterium tuberculosis complex (MTBC) DNA quantitative real-time polymerase chain reaction (qPCR) detection kit for African wildlife samples. DNA was extracted from tissues harvested from 48 African buffaloes and MTBC DNA was detected (test-positive) in all 26 M. bovis culture-confirmed animals with an additional 12 PCR-positive results in culture-negative buffaloes (originating from an exposed population). Of six MTBC-infected African rhinoceros tested, MTBC DNA was detected in antemortem and postmortem samples from five animals. The PCR was also able to detect MTBC DNA in samples from two African elephants confirmed to have M. bovis and M. tuberculosis infections (one each). Culture-confirmed uninfected rhinoceros and elephants’ samples tested negative in the PCR assay. Conclusions These results suggest this new detection kit is a sensitive screening test for the detection of MTBC-infected African buffaloes, African elephants and white rhinoceros.
- Published
- 2020
31. Viruses as indicators of contemporary host dispersal and phylogeography: an example of feline immunodeficiency virus (FIVPle) in free-ranging African lion (Panthera leo)
- Author
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Sonja Matthee, Danny Govender, Gerard Tromp, Conrad A. Matthee, Tanya J. Kerr, and Susan Engelbrecht
- Subjects
0106 biological sciences ,0301 basic medicine ,education.field_of_study ,Feline immunodeficiency virus ,biology ,Phylogenetic tree ,National park ,Population ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,03 medical and health sciences ,Phylogeography ,030104 developmental biology ,Phylogenetics ,Evolutionary biology ,biology.animal ,Biological dispersal ,Panthera ,education ,Ecology, Evolution, Behavior and Systematics - Abstract
Measuring contemporary dispersal in highly mobile terrestrial species is challenging, especially when species are characterized by low levels of population differentiation. Directly transmitted viruses can be used as a surrogate for traditional methods of tracking host movement. Feline immunodeficiency virus (FIV) is a species-specific lentivirus, which has an exceptionally high mutation rate and circulates naturally in wild felids. Using samples derived from 35 lion (Panthera leo) prides, we tested the prediction that FIV in lions (FIVP le ) can be used to track the dispersal of individuals between prides. As FIVP le subtypes are geographically structured throughout Africa, we predicted that this marker could be used to detect phylogeographic structure of lions at smaller spatial scales. Phylogenetic analyses of FIVP le pol-RT sequences showed that core pride members (females and subadults) shared evolutionary close viral lineages which differed from neighbouring core prides, whereas sequences from sexually mature males associated with the same pride were always the most divergent. In six instances, natal pride associations of divergent male lions could be inferred, on the assumption that FIVP le infections are acquired during early life stages. Congruence between the genetic pattern of FIV and pride structure suggests that vertical transmission plays an important role in lion FIV dynamics. At a fine spatial scale, significant viral geographic structuring was also detected between lions occurring north of the Olifants River within the Kruger National Park (KNP) and those occupying the southern and central regions. This pattern was further supported by phylogenetic analyses and the confinement of FIVP le subtype E to the northern region of KNP. The study provides new insights into the use of retroviral sequences to predict host dispersal and fine-scale contemporary geographic structure in a social felid species.
- Published
- 2018
32. Evaluating the Diversity of the Feline Immunodeficiency Virus (FIV): A Leopard Perspective
- Author
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Conrad A. Matthee, Tanya J. Kerr, Sonja Matthee, Danny Govender, and Susan Engelbrecht
- Subjects
0301 basic medicine ,Feline immunodeficiency virus ,Ecology ,biology ,Phylogenetic tree ,National park ,viruses ,Home range ,Zoology ,Leopard ,Geographic variation ,Feline immunodeficiency virus FIV ,biology.organism_classification ,Virology ,03 medical and health sciences ,030104 developmental biology ,biology.animal ,Animal Science and Zoology ,Panthera - Abstract
To obtain more insights into the prevalence and diversity of species-specific Feline Immunodeficiency Virus (FIV) strains in naturally occurring felid species, 26 leopards (Panthera pardus) from the Kruger National Park (KNP), South Africa, were sampled. Prevalence was determined using a PCR protocol designed to target a 577 bp fragment in the pol-RT gene. Overall prevalence of FIVPpa was estimated at 73%, with no difference in prevalence between male and female leopards. Consistent with previous FIV studies on other felid species, prevalence appears to increase with age (adult = 84%; subadult = 43%). Phylogenetic analyses of these novel sequences were conducted against a revised FIV pol-RT species-specific reference dataset using both Bayesian and maximum likelihood methods. Within FIVPpa two distinct evolutionary groupings are present, which suggests the possibility of geographic variation within FIVPpa and the possibility of distinct subtypes, similar to what has been found in lions (Panthera leo) and domestic cats (Felis catus). The larger FIVPpa dataset provides newinsights into the epidemiology of this under-studied FIV strain and with such high prevalence rates, further studies should focus on immunological and clinical consequences of FIV in wild felids.
- Published
- 2017
33. Novel Techniques for Detection of Mycobacterium bovis Infection in a Cheetah
- Author
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Tanya J. Kerr, Rachiel Gumbo, Wynand J. Goosen, Peter Rogers, Robert D. Last, and Michele A. Miller
- Subjects
Microbiology (medical) ,CXCL9 gene expression assay ,Epidemiology ,030231 tropical medicine ,detection ,lcsh:Medicine ,Biology ,lcsh:Infectious and parasitic diseases ,03 medical and health sciences ,0302 clinical medicine ,biology.animal ,Bovine tuberculosis ,Research Letter ,Acinonyx jubatus ,lcsh:RC109-216 ,030212 general & internal medicine ,bovine tuberculosis ,cheetah ,bacteria ,novel techniques ,Mycobacterium bovis ,lcsh:R ,Diagnostic test ,Novel Techniques for Detection of Mycobacterium bovis Infection in a Cheetah ,biology.organism_classification ,Virology ,tuberculosis and other mycobacteria ,zoonoses ,Infectious Diseases - Abstract
In South Africa, bovine tuberculosis threatens some of Africa's most iconic wildlife species, including the cheetah (Acinonyx jubatus). The lack of antemortem diagnostic tests for this species strongly hinders conservation efforts. We report use of antemortem and postmortem diagnostic assays to detect Mycobacterium bovis infection in a cheetah.
- Published
- 2020
34. The Xpert MTB/RIF Ultra assay detects Mycobacterium tuberculosis complex DNA in white rhinoceros (Ceratotherium simum) and African elephants (Loxodonta africana)
- Author
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David H. Persing, Sven D.C. Parsons, Michele A. Miller, Wynand J. Goosen, Robin M. Warren, Léanie Kleynhans, Paul D. van Helden, Peter Buss, and Tanya J. Kerr
- Subjects
0301 basic medicine ,DNA, Bacterial ,Tuberculosis ,Molecular biology ,Elephants ,lcsh:Medicine ,Rhinoceros ,Diseases ,Sensitivity and Specificity ,Article ,Microbiology ,03 medical and health sciences ,0302 clinical medicine ,Medical research ,Limit of Detection ,medicine ,Animals ,Humans ,lcsh:Science ,Inhibitory effect ,Antibiotics, Antitubercular ,Perissodactyla ,Multidisciplinary ,biology ,Molecular medicine ,Ceratotherium simum ,Diagnostic Tests, Routine ,lcsh:R ,Sputum ,Reproducibility of Results ,Mycobacterium tuberculosis complex DNA ,Mycobacterium tuberculosis ,biology.organism_classification ,medicine.disease ,Mycobacterium bovis ,White (mutation) ,030104 developmental biology ,Mycobacterium tuberculosis complex ,lcsh:Q ,Biological Assay ,Culture negative ,Rifampin ,Bronchoalveolar Lavage Fluid ,030217 neurology & neurosurgery - Abstract
The study describes the novel use of the Xpert MTB/RIF Ultra assay for detection of Mycobacterium tuberculosis complex (MTBC) DNA in samples from white rhinoceros (Ceratotherium simum) and African elephants (Loxodonta africana). Culture negative respiratory sample matrices were spiked to determine if the Ultra could detect MTBC DNA in rhinoceros and elephant samples. Rhinoceros bronchial alveolar lavage fluid (BALF) was found to have an inhibitory effect on the Ultra. In this study, the limit of detection (LOD) of M. tuberculosis H37Rv in all spiked animal samples were 2 CFU/ml compared to 15.6 CFU/ml for humans, while the LOD for M. bovis SB0121 was 30 CFU/ml compared to 143.4 CFU/ml for M. bovis BCG in humans. Screening was performed on stored tissue and respiratory samples from known MTBC-infected animals and MTBC DNA was detected in 92% of samples collected from six rhinoceros and two elephants. Conversely, 83% of culture-negative tissue and respiratory samples from uninfected animals tested negative on the Ultra. In conclusion, the Ultra assay appears to be a sensitive and rapid diagnostic test for the detection of MTBC DNA from tissue and respiratory samples collected from African elephants and rhinoceros. Furthermore, the Ultra assay could provide a new tool for the detection of MTBC in various sample types from other wildlife species.
- Published
- 2019
35. Seroprevalence of
- Author
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Tanya J, Kerr, Candice R, de Waal, Peter E, Buss, Jennifer, Hofmeyr, Konstantin P, Lyashchenko, and Michele A, Miller
- Subjects
Male ,Aging ,South Africa ,Seroepidemiologic Studies ,Elephants ,Animals ,Tuberculosis ,Animals, Wild ,Female ,Mycobacterium tuberculosis ,Antibodies, Bacterial - Abstract
Tuberculosis (TB) is a pathogenic disease that affects a range of wildlife species, including African elephants (
- Published
- 2019
36. The use of Raman spectroscopy to monitor phase changes in concrete following high temperature exposure
- Author
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Elisa Nauha, Tanya J. Kerr, Marleen Vetter, and Jose Gonzalez-Rodriguez
- Subjects
Diffraction ,Materials science ,0211 other engineering and technologies ,Analytical chemistry ,020101 civil engineering ,02 engineering and technology ,Building and Construction ,engineering.material ,F180 Analytical Chemistry ,0201 civil engineering ,symbols.namesake ,chemistry.chemical_compound ,F110 Applied Chemistry ,chemistry ,021105 building & construction ,engineering ,symbols ,General Materials Science ,Thermal damage ,Gehlenite ,F200 Materials Science ,Calcium silicate hydrate ,Raman spectroscopy ,Civil and Structural Engineering - Abstract
Concrete is one of the most widely used construction materials, having excellent mechanical properties, but may fail in a catastrophic manner post fire. In this study, we present non-destructive Raman testing of concrete walls post fire to track temperature exposure based on the decomposition of the calcium silicate hydrate (CSH) phase. The use of Raman spectroscopy is contrasted with X-ray diffraction to demonstrate its competence in evaluating thermal damage to concrete. It was found that Raman spectroscopy was more adept at identifying the hydrated phases than XRD. Principal component analysis was applied to the Raman data to demonstrate the ability of Raman spectroscopy to distinguish concrete exposed to different temperatures. The decomposition of Calcium silicate hydrate could be followed by Raman monitoring the shifts at 1081, 709 and 278 cm−1. At the highest temperature in this study (950 °C) Raman spectra showed the disappearance of these bands with formation of a new one at 1007 cm−1 attributed to the formation of gehlenite following the matrix decomposition.
- Published
- 2019
37. Test Characteristics of Assays to Detect Mycobacterium bovis Infection in High-Prevalence African Buffalo (Syncerus caffer) Herds
- Author
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Sven D.C. Parsons, Michele A. Miller, Tanya J. Kerr, Paul D. van Helden, David Cooper, Netanya Bernitz, Robin M. Warren, and Candice R. de Waal
- Subjects
Mycobacterium bovis ,High prevalence ,Ecology ,biology ,040301 veterinary sciences ,Infection prevalence ,030231 tropical medicine ,Mycobacterial culture ,04 agricultural and veterinary sciences ,biology.organism_classification ,Virology ,0403 veterinary science ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Herd ,Interferon gamma ,Ecology, Evolution, Behavior and Systematics ,medicine.drug - Abstract
A herd of African buffaloes (Syncerus caffer) was tested for Mycobacterium bovis infection using three cytokine release assays. All animals were subsequently euthanized and mycobacterial culture determined the infection prevalence (52%) and diagnostic characteristics. Sensitivities were lower than previously reported and results provide new insight into the practical utility of these assays.
- Published
- 2020
38. Impact of Mycobacterium bovis-induced pathology on interpretation of QuantiFERON®-TB Gold assay results in African buffaloes (Syncerus caffer)
- Author
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Michele A. Miller, Paul D. van Helden, Netanya Bernitz, Roxanne L. Higgitt, Candice R. de Waal, Tanya J. Kerr, Sven D.C. Parsons, Charlene Clarke, Robin M. Warren, David Cooper, and Wynand J. Goosen
- Subjects
Buffaloes ,QUANTIFERON-TB GOLD ,medicine.medical_treatment ,Immunology ,Biology ,Sensitivity and Specificity ,Microbiology ,Interferon-gamma ,Interferon ,parasitic diseases ,Bovine tuberculosis ,medicine ,Animals ,Interferon gamma ,Whole blood ,Mycobacterium bovis ,General Veterinary ,biology.organism_classification ,Chemokine CXCL10 ,Cytokine ,Biomarker (medicine) ,Cattle ,Reagent Kits, Diagnostic ,Tuberculosis, Bovine ,Interferon-gamma Release Tests ,medicine.drug - Abstract
The cytokine interferon gamma-inducible protein 10 (IP-10) is a sensitive biomarker of Mycobacterium bovis (M. bovis) infection in African buffaloes (Syncerus caffer). However, elevated levels of IP-10 in QuantiFERON®-TB Gold (QFT) unstimulated whole blood compromises the utility of this biomarker. In this study, IP-10 and interferon gamma (IFN-γ) concentrations in whole blood samples from M. bovis culture-confirmed buffaloes with varying degrees of pathological changes (n = 72) and uninfected controls (n = 70) were measured in the IP-10 release assay (IPRA) and IFN-γ release assay (IGRA), respectively. Findings suggest that concentrations of both cytokines in QFT Nil tubes were higher in infected buffaloes with macroscopic pathological changes consistent with bovine tuberculosis compared to uninfected controls, and IGRA values increased with more severe pathological changes in infected buffaloes (p 0.05). Finally, in culture-confirmed buffaloes with IPRA-negative and IGRA-positive test results, most animals were also those with the most advanced pathology. We conclude that IP-10 and IFN-γ concentrations measured in QFT Nil tubes may provide insight into the presence of M. bovis pathology in infected buffaloes. Furthermore, this study highlights the value in evaluating cytokine production in both antigen-stimulated and unstimulated samples when interpreting cytokine release assay results.
- Published
- 2019
39. Sample preparation for the analysis of fire debris - Past and present
- Author
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Tanya J. Kerr
- Subjects
Waste management ,010401 analytical chemistry ,New materials ,Filtration and Separation ,Alternative fuels ,01 natural sciences ,Debris ,0104 chemical sciences ,Analytical Chemistry ,Arson ,03 medical and health sciences ,0302 clinical medicine ,Environmental science ,Sample preparation ,030216 legal & forensic medicine - Abstract
Identification of ignitable liquids from fire debris is such a major part of an arson investigation that much time and effort has gone into advancing sample preparation techniques to capture complicated and unexpected hydrocarbon compounds. Advancements in sample preparation have been made in order to account for biodegradation of commonly used accelerants, rarely encountered compounds, such as vegetable oils, biodiesel, and alcohols. Improvements have also been made to manage interference from the sample matrix, particularly with regards to new materials. This paper is a review of the sample preparation techniques that are foundational to fire debris analysis as well as recent advances. Also explored are modifications to the traditional sample preparation methods to accommodate the analysis of environmental samples (soil and water), and the presence of vegetable oils and biofuels on the fire scene.
- Published
- 2018
40. Viruses as indicators of contemporary host dispersal and phylogeography: an example of feline immunodeficiency virus (FIV
- Author
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Tanya J, Kerr, Sonja, Matthee, Danny, Govender, Gerard, Tromp, Susan, Engelbrecht, and Conrad A, Matthee
- Subjects
Lions ,Male ,Genetic Variation ,Immunodeficiency Virus, Feline ,Infectious Disease Transmission, Vertical ,Phylogeography ,South Africa ,Haplotypes ,Feline Acquired Immunodeficiency Syndrome ,Host-Pathogen Interactions ,Cats ,Prevalence ,Animals ,Female ,Phylogeny - Abstract
Measuring contemporary dispersal in highly mobile terrestrial species is challenging, especially when species are characterized by low levels of population differentiation. Directly transmitted viruses can be used as a surrogate for traditional methods of tracking host movement. Feline immunodeficiency virus (FIV) is a species-specific lentivirus, which has an exceptionally high mutation rate and circulates naturally in wild felids. Using samples derived from 35 lion (Panthera leo) prides, we tested the prediction that FIV in lions (FIV
- Published
- 2017
41. Seroprevalence of Mycobacterium tuberculosis Complex in Free-Ranging African Elephants (Loxodonta africana) in Kruger National Park, South Africa
- Author
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Konstantin P. Lyashchenko, Candice R. de Waal, Tanya J. Kerr, Peter Buss, Jennifer Hofmeyr, and Michele A. Miller
- Subjects
education.field_of_study ,Tuberculosis ,Ecology ,biology ,040301 veterinary sciences ,National park ,030231 tropical medicine ,Population ,04 agricultural and veterinary sciences ,biology.organism_classification ,medicine.disease ,Serology ,0403 veterinary science ,Mycobacterium tuberculosis ,African elephant ,03 medical and health sciences ,0302 clinical medicine ,Mycobacterium tuberculosis complex ,biology.animal ,medicine ,Seroprevalence ,education ,Ecology, Evolution, Behavior and Systematics ,Demography - Abstract
Tuberculosis (TB) is a pathogenic disease that affects a range of wildlife species, including African elephants (Loxodonta africana). The recent discovery of fatal disease caused by infection with Mycobacterium tuberculosis in a bull elephant in the Kruger National Park (KNP), which is a bovine TB endemic area, emphasizes the importance this disease could have on both wild and captive elephant populations globally. Elephants with culture-confirmed TB have previously been shown to produce strong antibody-responses before the mycobacteria can be isolated. Therefore, we used two serologic assays that detect TB antibodies to retrospectively screen a cohort of 222 free-ranging African elephants sampled between 2004 and 2018 in KNP. The estimated TB seroprevalence for this free-roaming elephant population was between 6% (95% confidence interval [CI], 2-12%) and 9% (95% CI, 6-15%) based on the two tests. Overall, males had a higher TB seroprevalence than females, and adults (≥25 yr) had a higher TB seroprevalence than younger elephants (≤24 yr) on both rapid tests. The relatively high TB seroprevalence that we found highlighted the value of conducting retrospective studies in free-ranging wildlife populations in order to better understand the potential risk of disease.
- Published
- 2019
42. Application of vibrational spectroscopy techniques for material identification from fire debris
- Author
-
Tanya J. Kerr, Keith L. Duncan, and Leary Myers
- Subjects
Materials science ,Analytical chemistry ,Infrared spectroscopy ,Fire investigation ,Chemometrics ,Low-density polyethylene ,symbols.namesake ,symbols ,High-density polyethylene ,Fourier transform infrared spectroscopy ,Composite material ,Spectroscopy ,Raman spectroscopy - Abstract
The primary goal of this research is to demonstrate the use of vibrational spectroscopy techniques as a tool for the identification of materials post fire. This paper discusses the use micro-Raman spectroscopy and ATR-FTIR to identify materials found in fire debris. The polymeric materials under study were high density and low density polyethylene (HDPE and LDPE), polyvinyl chloride (PVC), polymethyl methacrylate (PMMA) and cotton. These are commonly materials found in households around the world, their identification from the debris provides useful forensic information on the spatial distribution of fuels in a fire compartment, thus allowing for accurate analysis and modelling. Earlier work has established Raman spectroscopy to be a very good tool for material identification post fire. The addition of ATR-FTIR spectroscopy as a technique in developing this novel tool for identification of materials post fire has established vibrational spectroscopy in the area of fire investigation. This study indicated that the limitations associated with Raman spectroscopy in post fire identification, could be made insignificant by the strengths of ATR-FTIR spectroscopy and vice versa. To further establish the validity of this identification process principal component analysis was used to discriminate between the spectrum of the burnt materials and an error analysis computed. Both techniques demonstrated that identification could be done with very minimal confusion between the materials studied.
- Published
- 2013
43. Post fire materials identification by micro-Raman spectroscopy and principal components analysis
- Author
-
Leary Myers, Keith L. Duncan, and Tanya J. Kerr
- Subjects
Polypropylene ,chemistry.chemical_classification ,Materials science ,Thermal decomposition ,Polymer ,Analytical Chemistry ,Polyester ,chemistry.chemical_compound ,symbols.namesake ,Fuel Technology ,chemistry ,symbols ,Polystyrene ,Composite material ,Spectroscopy ,Raman spectroscopy ,Pyrolysis - Abstract
The chemical and physical characteristics of thermally damaged polymers, found in fire debris are studied using micro-Raman spectroscopy for identifying original materials in a fire compartment. Six polymeric materials commonly found in households were selected for the initial study. They are, polypropylene (DVD case), polystyrene foam (plates), polyurethane (sofa foam), polyester (PET curtains), Ethylene vinylacetate (EVA shower curtains) and nylon (stockings). Raman shifts were obtained for each material prior to them, being burnt as the baseline for determining the loss of Raman bands due to a material modification by the fire. Each material was then burnt, and the subsequent Raman spectra collected. The average Raman spectra for each material were subjected to principal component analysis, which showed that after thermal decomposition, Raman spectroscopy could be used to identify and differentiate materials found in burnt debris. Raman spectra for each material were distinguishable in the sample group and could then be used for identification of the material in their post fire state.
- Published
- 2013
44. Raman Microspectroscopic Mapping: A Tool for Identification of Fused Materials in Fire Debris
- Author
-
Leary Myers, Tanya J. Kerr, and Keith L. Duncan
- Subjects
010407 polymers ,Engineering ,business.industry ,02 engineering and technology ,Structural engineering ,Raman mapping ,021001 nanoscience & nanotechnology ,01 natural sciences ,Debris ,0104 chemical sciences ,Pathology and Forensic Medicine ,Fire investigation ,Identification (information) ,symbols.namesake ,Genetics ,symbols ,0210 nano-technology ,business ,Raman spectroscopy ,Remote sensing - Abstract
Examination of fire debris can provide information about the types of materials which were present at the time of the fire to give insights for fire scene reconstruction and understanding compartment fire dynamics. This paper demonstrates the ability of Raman spectroscopy for material identification postfire in complex situations, such as the production of fused masses during fire dropdown. A validated Raman spectral library is combined with Raman mapping in three fire case studies, to determine the individual materials in the fused masses formed. The case studies accessed material combinations of several common polymers. Raman mapping was carried out on a 10 μm × 10 μm square of the masses. Material identification using this technique ranged from a high of 85% match to a low of 40% match. This work demonstrated that complex masses found in the fire debris can be resolved into the individual material components for identification and spatial distribution.
- Published
- 2016
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