scholarly journals Comparitive study on the efficacy of ELISA and IS900 PCR for the diagnosis of Paratuberculosis in goats

2014 ◽  
Vol 30 (4) ◽  
pp. 661-667 ◽  
Author(s):  
A. Abraham ◽  
N. Thomas ◽  
S. Joseph ◽  
K.C. Raghavan

Paratuberculosis, one of the chronic granulomatous enteritis that predominantly affects ruminants worldwide, is caused by Mycobacterium avium subsp. paratuberculosis (MAP). It is most efficiently diagnosed by MAP from faeces by Polymerase Chain Reaction (PCR). Serological tests like Enzyme Linked Immuno Sorbent Assay (ELISA) also provides a rapid and cost-effective alternative diagnostic tool. Present study was carried out to directly evaluate the sensitivity and specificity of ELISA (ID vet innovative diagnostics; France) using IS900 PCR as a gold standard. Serum and faecal samples were collected from 180 adult goats of either sex, from Malappuram and Thrissur districts of Kerala with unknown paratuberculosis status. Faecal samples were processed for direct IS900 PCR and serum samples were tested for MAP antibodies using Indirect ELISA kit. IS900 PCR detected 38 out of 180 confirmed to be shedding MAP. ELISA detected 22 out of 180 animals as positive. Overall, ELISA was 50 % sensitive and 97.9 % specific in comparison to IS900 PCR. The IS900 PCR outperformed ELISA in detecting animals potentially infected with MAP and is more sensitive than ELISA at detecting animals suspected of paratuberculosis. But, for early diagnosis of paratuberculosis in goats, ELISA can be done as easy and rapid farm level identification and IS900 PCR as individual confirmatory test.

2010 ◽  
Vol 12 (4) ◽  
pp. 351-354 ◽  
Author(s):  
Francesca Mancianti ◽  
Simona Nardoni ◽  
Gaetano Ariti ◽  
Dario Parlanti ◽  
Giovanna Giuliani ◽  
...  

Cats are the key species in the epidemiology of Toxoplasma gondii infection, even if the proportion of subjects excreting oocysts is low. The aim of the present paper was to obtain information about seroprevalence, oocyst shedding rate and presence of T gondii DNA in faeces collected from an urban population of colony cats in Florence (Tuscany). Fifty European shorthair feral cats were examined for anti- T gondii specific antibodies by a modified agglutination test (MAT), and for oocysts by microscopic examination and for faecal protozoal DNA, by means of a nested polymerase chain reaction (n-PCR) protocol. Twenty-two out of 50 serum samples (44%) were MAT positive. T gondii oocysts were not detected in any of the examined faecal samples. Eight out of 50 faecal specimens (16%) were n-PCR positive and sequencing of the bands was specific for T gondii. Detection by combination of the two methods was higher than single techniques and enhanced the detection of T gondii up to 48%. Our results suggest that the use of MAT plus PCR in faeces may be the best choice for diagnosis of feline toxoplasmosis. Further studies to ascertain the real infectivity of the copro-PCR positive subjects are required.


Author(s):  
Sangram Biswal ◽  
Adya Prakash Rath ◽  
Shoor Vir Singh ◽  
Niranjana Sahoo ◽  
Saurabh Gupta ◽  
...  

Paratuberculosis is caused by Mycobacterium avium subsp. Paratuberculosis (MAP) and is a chronic, intestinal tract infection in the ruminant sector globally. A total of 122 EDTA mixed blood samples, 121 serum and 16 pooled faecal samples were collected from farms of 4 different districts i.e. Nayagarh, Cuttack, Khordha and Angul and a blind review was conducted at the Animal Health Division, CIRG, Mathura. Microscopic examination of 16 pooled faecal samples revealed +2 reactivity to Acid-Fast Bacilli. All the serum samples were subjected to indirect ELISA. Out of them, 23 (19.01%), 85 (70.25%), shows strongly positive, positive, antibody titre respectively. EDTA blood samples of 23 ELISA-strongly positive were subjected to 413 bp IS900 PCR and 11 (9%) of them were found positive for Mycobacterium avium subsp. Paratuberculosis (MAP). MAP isolates were further subjected to genotyping using 608 bpIS1311 PCR and restriction endonuclease analysis (IS1311 PCR-REA) and 2 (1.64%) of them matched with “Indian Bison Type”. Genotyping of the isolates using IS1311 PCR-REA revealed that goat population of Odisha are primarily infected with “Indian Bison Type” strains.


2021 ◽  
Vol 9 ◽  
Author(s):  
Dhanasekaran Sakthivel ◽  
David Delgado-Diaz ◽  
Laura McArthur ◽  
William Hopper ◽  
Jack S. Richards ◽  
...  

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a recently emerged and highly contagious virus that causes coronavirus disease 2019 (COVID-19). As of August 24, 2021, there were more than 212 million confirmed COVID-19 cases and nearly 4.4 million deaths reported globally. Early diagnosis and isolation of infected individuals remains one of the most effective public health interventions to control SARS-CoV-2 spread and for effective clinical management of COVID-19 cases. Currently, SARS-CoV-2 infection is diagnosed presumptively based on clinical symptoms and confirmed by detecting the viral RNA in respiratory samples using reverse transcription polymerase chain reaction (RT-PCR). Standard RT-PCR protocols are time consuming, expensive, and technically demanding, which makes them a poor choice for large scale and point-of-care screening in resource-poor settings. Recently developed isothermal nucleic acid amplification tests (iNAAT), antigen and/or serological tests are cost-effective to scale COVID-19 testing at the point-of-care (PoC) and for surveillance activities. This review discusses the development of rapid PoC molecular tools for the detection and surveillance of SARS-CoV-2 infections.


2018 ◽  
Vol 68 (2) ◽  
pp. 167
Author(s):  
A. C. COELHO ◽  
A. M. COELHO ◽  
J. GARCÍA-DIEZ ◽  
M. A. PIRES ◽  
M. L. PINTO

A total of thirty sheep with clinical symptomatology of paratuberculosis (Johne’s disease) were subjected to four diagnostic techniques: histopathological examination, bacteriological culture (in faeces and tissues), polymerase chain reaction (PCR) (in blood, tissue and faecal samples) and antibody responses (ELISA). Twenty-one (70.0%) animals showed histological lesions. Bacterial culture of both faeces and tissue revealed that 2 (6.7%) and 6 (20.0%) of the 30 sheep were infected, respectively. Mycobacterium avium subsp. 24 paratuberculosis (Map) was identified in 4 animals via PCR of faeces (13.3%), and in 19 (63.3%) by PCR in tissues. PCR in blood revealed 7 (23.3%) infected animals. Three (10.0%) animals showed antibodies against Map. A greater number of positive animals were detected by histopathological examination and PCR in tissues than by culture or ELISA. This study confirmed the clinical findings and results suggest that histopathology, PCR in tissues and in blood can improve the detection of Map in physically suspected animals and should be considered useful tools in the diagnosis of Map in suspected sheep.


2014 ◽  
Vol 21 (8) ◽  
pp. 1077-1085 ◽  
Author(s):  
José M. Prieto ◽  
Ana Balseiro ◽  
Rosa Casais ◽  
Naiara Abendaño ◽  
Liam E. Fitzgerald ◽  
...  

ABSTRACTThe enzyme-linked immunosorbent assay (ELISA) is the diagnostic test most commonly used in efforts to control paratuberculosis in domestic ruminants. However, commercial ELISAs have not been validated for detecting antibodies againstMycobacterium aviumsubsp.paratuberculosisin wild animals. In this study, we compared the sensitivities and specificities of five ELISAs using individual serum samples collected from 41 fallow deer with or without histopathological lesions consistent with paratuberculosis. Two target antigenic preparations were selected, an ethanol-treated protoplasmic preparation obtained from a fallow deerM. aviumsubsp.paratuberculosisisolate (ELISAs A and B) and a paratuberculosis protoplasmic antigen (PPA3) (ELISAs C and D). Fallow deer antibodies bound to the immobilized antigens were detected by using a horseradish peroxidase (HRP)-conjugated anti-fallow deer IgG antibody (ELISAs A and C) or HRP-conjugated protein G (ELISAs B and D). A commercially available assay, ELISA-E, which was designed to detectM. aviumsubsp.paratuberculosisantibodies in cattle, sheep, and goats, was also tested. Although ELISAs A, C, and E had the same sensitivity (72%), ELISAs A and C were more specific (100%) for detecting fallow deer with lesions consistent with paratuberculosis at necropsy than was the ELISA-E (87.5%). In addition, the ELISA-A was particularly sensitive for detecting fallow deer in the latent stages of infection (62.5%). The antibody responses detected with the ELISA-A correlated with both the severity of enteric lesions and the presence of acid-fast bacteria in gut tissue samples. In summary, our study shows that the ELISA-A can be a cost-effective diagnostic tool for preventing the spread of paratuberculosis among fallow deer populations.


2021 ◽  
Author(s):  
Aregawi Girmay ◽  
Atitegeb Sisay ◽  
Shiret Belete

Abstract Background: In Ethiopia, brucellosis has been reported targeted on bovine, occasionally on shoat, and rarely on camels. An investigation of the disease Brucellosis in the neglected companion animals is scared in Ethiopia. The objective of this study was to identify canine brucellosis in Batu town, Alage and Naka village through cross sectional approaches. A total of 389 serum samples (207 from Batu, 107 from Alage, and 75 from Naka) were collected by restraining dogs with a portable and safe modified dog crush, invented by this author. Blood samples were collected from ear vein and sera were screened for Brucella antibodies using different serological tests. RBPT prepared from the smooth strain B. abortus antigen and CFT was used as a screening test and confirmatory test, respectively. Furthermore, all sera samples had also screened by RBPTcanis antigen (rough strain); and those positive were considered the cause for B. canis infection. Results: Using RBPT smooth strains, 21(5.4%; CI: 3.35, 7.96) were positive and 19(4.88%; CI: 2.7, 7.0) were confirmed by CFT. Besides, 34 (8.74%; CI: 5.92, 11.56) were positive for RBPTcanis rough strains. Relatively, higher proportion of anti B. canis antibodies had seen in Batu (11.59%) followed by Alage (5.61%), and Naka (5.33%). Sex, living condition, and history of obstetrical problem were significantly associated with the occurrence of canine brucellosis (p< 0.05). Odd of canine brucellosis due to smooth and rough strains in outdoor dogs were 4.72 and 6.42 times higher compared with indoors, respectively. This is true the fact that outdoors had a chance of getting infected aborted wastes when roaming freely. Conclusion: This study suggests that canine brucellosis is prevalent in the province. The seropositivity could give an insight that, the awareness of the people toward the disease was also the gap in the study area. Hence, this warrants public education among the community is recommended.


2020 ◽  
Author(s):  
Danielle Dias Conte ◽  
Joseane Mayara Almeida Carvalho ◽  
Luciano Kleber de Souza Luna ◽  
Klinger Soares Faíco-Filho ◽  
Ana Helena Perosa ◽  
...  

AbstractSince the Coronavirus Disease 2019 (COVID-19) pandemic, Brazil has the third-highest number of confirmed cases and the second-highest number of recovered patients. SARS-CoV-2 detection by real-time RT-PCR is the gold standard in certified infrastructured laboratories. However, for large-scale testing, diagnostics should be fast, cost-effective, widely available, and deployed for the community, such as serological tests based on lateral flow immunoassay (LFIA) for IgM/IgG detection. We evaluated three different commercial point-of-care (POC) LFIAs for anti-SARS-CoV-2 IgM and IgG detection in capillary whole blood of 100 healthcare workers (HCW) previously tested by RT-PCR: 1) COVID-19 IgG/IgM BIO (Bioclin, Brazil), 2) Diagnostic kit for IgM/IgG Antibody to Coronavirus (SARS-CoV-2) (Livzon, China); and 3) SARS-CoV-2 Antibody Test (Wondfo, China). A total of 84 positives and 16 negatives HCW were tested. The data was also analyzed by the number of days post symptoms (DPS) in three groups: <30 (n=26), 30-59 (n=42), and >59 (n=16). Overall detection was 85.71%, 47.62%, and 44.05% for Bioclin, Livzon, and Wondfo, respectively, with a specificity of 100%, and 98.75% for Livzon on storage serum samples. Bioclin was more sensitive (p<0.01), regardless of the DPS. Thus, the Bioclin can be used as a POC test to monitor SARS-CoV-2 seroconversion in HCW.


2021 ◽  
Vol 31 (1) ◽  
pp. 121-133
Author(s):  
Andrea Tešija Kuna ◽  
Marijana Miler ◽  
Mario Štefanović ◽  
Ivan Šamija ◽  
Josipa Periša ◽  
...  

Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological tests have been suggested as an additional diagnostic tool in highly suspected cases with a negative molecular test and determination of seroprevalence in population. We compared the diagnostic performance of eight commercial serological assays for IgA, IgM, and IgG antibodies to the SARS-CoV-2 virus. Materials and methods: The comparison study was performed on a total of 76 serum samples: 30 SARS-CoV-2 polymerase chain reaction (PCR)- negative and 46 SARS-CoV-2 PCR-positive patients with asymptomatic to severe disease and symptoms duration from 3-30 days. The study included: three rapid lateral flow immunochromatographic assays (LFIC), two enzyme-linked immunosorbent assays (ELISA), and three chemiluminescence immunoassays (CLIA). Results: Agreement between IgM assays were minimal to moderate (kappa 0.26 to 0.63) and for IgG moderate to excellent (kappa 0.72 to 0.92). Sensitivities improved with > 10 days of symptoms and were: 30% to 89% for IgM; 89% to 100% for IgG; 96% for IgA; 100% for IgA/IgM combination; 96% for total antibodies. Overall specificities were: 90% to 100% for IgM; 85% to 100% for IgG; 90% for IgA; 70% for IgA/IgM combination; 100% for total antibodies. Diagnostic accuracy for IgG ELISA and CIA assays were excellent (AUC ≥ 0.90), without significant difference. IgA showed significantly better diagnostic accuracy than IgM (P < 0.001). Conclusion: There is high variability between IgM assays independently of the assay format, while IgG assays showed moderate to perfect agreement. The appropriate time for testing is crucial for the proper immunity investigation.


Viruses ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 849 ◽  
Author(s):  
Petra Wandernoth ◽  
Katharina Kriegsmann ◽  
Cristina Groh-Mohanu ◽  
Martin Daeumer ◽  
Peter Gohl ◽  
...  

Background: Amplification of viral ribonucleic acid (RNA) by real-time reverse transcriptase polymerase chain reaction (rRT-PCR) is the gold standard to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since the initial outbreak, strategies to detect and isolate patients have been important to avoid uncontrolled viral spread. Although testing capacities have been upscaled, there is still a need for reliable high throughput test systems, specifically those that require alternative consumables. Therefore, we tested and compared two different methods for the detection of viral PCR products: rRT-PCR and mass spectrometry (MS). Methods: Viral RNA was isolated and amplified from oro- or nasopharyngeal swabs. A total of 22 samples that tested positive and 22 samples that tested negative for SARS-CoV-2 by rRT-PCR were analyzed by MS. Results of the rRT-PCR and the MS protocol were compared. Results: Results of rRT-PCR and the MS test system were in concordance in all samples. Time-to-results was faster for rRT-PCR. Hands-on-time was comparable in both assays. Conclusions: MS is a fast, reliable and cost-effective alternative for the detection of SARS-CoV-2 from oral and nasopharyngeal swabs.


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