Evaluation of a rapid immunochromatographic test kit to the gold standard fluorescent antibody test for diagnosis of rabies in animals in Bhutan

Abstract Background: Rabies kills approximately 59,000 people in the world each year worldwide. Rapid and accurate diagnosis of rabies is important for instituting rapid containment measures and for advising the exposed people for postexposure treatment. The application of a rapid diagnostic tests in the field can greatly enhance disease surveillance activities, especially in resource poor settings.Methods: From 2012 to 2017, a total of 179 brain tissue samples collected from different animal species (113 dogs, 50 cattle, 10 cats, 3 goats, 2 horses, and 1 bear) suspected of having died due to rabies were selected and tested using the rapid immunochromatographic kit from BioNote© company and compared to the Gold Standard Fluorescent Antibody test (FAT) for diagnosis of rabies.Results: Among 179 samples examined in this study, there was concordance in results by the rapid test and FAT in 115 positive samples and 54 negative samples. Test result were discordant in 10 samples which were positive by FAT, but negative (false negative) by rapid kit. The rapid test kit showed a sensitivity of 92% (95% CI: 85.9 – 95.6) and specificity of 100% (95% CI: 93.4 – 100) using FAT as the gold standard. The positive and negative predicative values were found to be 100% (95% CI:96.7 – 100) and 84% (95% CI: 73.6 – 91.3), respectively. Overall there was 94.41% (95% CI: 90 – 96.9) test agreement (almost perfect agreement) between rapid test and FAT (Kappa value = 0.874).Conclusions: Our results demonstrate the potential value of the rapid test kit for countries with limited diagnostic resources, including Bhutan. The rapid kit’s inability to correctly detect 10 FAT-positive samples (10 out of 179 (5.6%) were false negatives) in our study could have been due to the low viral load in the samples (< 102.0LD50/0.03ml) which could not be detected by the rapid kit as compared with the FAT. The human factor related to the varying experiences of the technicians who performed the test in the field also may have influenced the test result. The rapid test kit is inexpensive, rapid and easy to use in the field or in laboratory setting without the need for special training and can support to enhance rabies surveillance in resource poor countries.

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Evaluation of a Rapid Immunochromatographic test kit to the Gold Standard Fluorescent Antibody Test for Diagnosis of Rabies in Animals in Bhutan

10.21203/rs.2.19414/v2 ◽

2020 ◽

Author(s):

Tenzin Tenzin ◽

Kelzang Lhamo ◽

Purna B Rai ◽

Dawa Tshering ◽

Pema Gyamtsho ◽

...

Keyword(s):

Predictive Value ◽

Fluorescent Antibody ◽

Rapid Test ◽

Antibody Test ◽

Immunochromatographic Test ◽

Reference Standard ◽

Predictive Values ◽

Percent Agreement ◽

Test Kit ◽

Resource Poor

Abstract Background Rabies kills approximately 59,000 people in the world each year worldwide. Rapid and accurate diagnosis of rabies is important for instituting rapid containment measures and for advising the exposed people for postexposure treatment. The application of a rapid diagnostic tests in the field can greatly enhance disease surveillance and diagnostic activities, especially in resource poor settings. A total of 179 brain tissue samples collected from different rabies suspect animal species (113 dogs, 50 cattle, 10 cats, 3 goats, 2 horses, and 1 bear) were selected and tested using both rapid immunochromatographic kit and the reference standard fluorescent antibody test (FAT). We evaluated the test sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of a rapid antigen detection test kit produced by BioNote, Inc. (Hwaseong-si, Korea) to a FAT for its fit-for-purpose for confirmation of clinical cases of rabies for early response, prevalence of infection (rabies surveillance), freedom for infection and eradication of rabies. ResultsAmong 179 samples examined in this study, there was a concordance in results by the rapid test and FAT in 115 positive samples and 54 negative samples. Test results were discordant in 10 samples which were positive by FAT, but negative (false negative) by rapid kit. The rapid test kit showed a sensitivity of 92% (95% CI: 85.9 – 95.6) and specificity of 100% (95% CI: 93.4 – 100) using FAT as the reference standard. The positive and negative predictive values were found to be 100% (95% CI:96.7 – 100) and 84.4% (95% CI: 73.6 – 91.3), respectively. Overall there was 94.4% (95% CI: 90 – 96.9) test agreement between rapid test and FAT (Kappa value = 0.874) with a positive percent agreement and negative percent agreement of 92 and 100%, respectively.Conclusions Our finding demonstrated that the rapid test kit (BioNote) can be used for confirming clinical case of rabies in animals for making rapid decisions including early medical intervention in human exposure and controlling rabies outbreaks in resource poor settings. Keywords: rabies virus; diagnostic test; fluorescent antibody test; rapid anigen test; rapid immunochromatographic test; Bhutan

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Evaluation of a rapid immunochromatographic test strip for detection of Rabies virus in dog saliva samples

Journal of Veterinary Diagnostic Investigation ◽

10.1177/1040638711425576 ◽

2011 ◽

Vol 23 (6) ◽

pp. 1197-1201 ◽

Cited By ~ 11

Author(s):

Songsri Kasempimolporn ◽

Wachiraporn Saengseesom ◽

Samrerng Huadsakul ◽

Supatsorn Boonchang ◽

Visith Sitprija

Keyword(s):

Rabies Virus ◽

Fluorescent Antibody ◽

Reference Method ◽

Antibody Test ◽

Test Strip ◽

Immunochromatographic Test ◽

Nested Polymerase Chain Reaction ◽

Epidemiological Surveys ◽

Test Kit ◽

Strip Test

An immunochromatographic test strip for Rabies virus was evaluated with dog saliva samples. The test was initially validated against 237 dogs of known infection status, and then evaluated in the field with 1,290 live dogs. By validation of paired saliva–brain specimens obtained from dogs at necropsy, the saliva strip test was 94.4% specific and 93.0% sensitive when compared to the gold standard fluorescent antibody test (FAT) on brain smears. The sensitivity and specificity of a nested polymerase chain reaction (nPCR) assay using saliva were 100% compared to the FAT results. The performance of strip test with field saliva samples from street dogs had a specificity of 98.7% in comparison to nPCR as the reference method. As the strip test kit can potentially be used outside the laboratory and be applicable as an on-site testing assay, it represents a powerful screening tool for epidemiological surveys and disease control. The test could be useful for the surveillance of rabies in dogs and, in particular, be used to monitor the success of rabies control programs.

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Evaluation of a Rapid Immunochromatographic test kit to the Gold Standard Fluorescent Antibody test for diagnosis of rabies in animals in Bhutan

10.21203/rs.2.19414/v3 ◽

2020 ◽

Author(s):

Tenzin Tenzin ◽

Kelzang Lhamo ◽

Purna B Rai ◽

Dawa Tshering ◽

Pema Jamtsho ◽

...

Keyword(s):

Predictive Value ◽

Fluorescent Antibody ◽

False Negative ◽

Rapid Test ◽

Antibody Test ◽

Reference Standard ◽

Predictive Values ◽

Percent Agreement ◽

Test Kit ◽

Resource Poor

Abstract Background: Rabies kills approximately 59,000 people in the world each year worldwide. Rapid and accurate diagnosis of rabies is important for instituting rapid containment measures and for advising the exposed people for postexposure treatment. The application of a rapid diagnostic tests in the field can greatly enhance disease surveillance and diagnostic activities, especially in resource poor settings. In this study, a total of 179 brain tissue samples collected from different rabies suspect animal species (113 dogs, 50 cattle, 10 cats, 3 goats, 2 horses, and 1 bear) were selected and tested using both rapid immunochromatographic kit and the reference standard fluorescent antibody test (FAT). We evaluated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of a rapid antigen detection test kit produced by BioNote, Inc. (Hwaseong-si, Korea) relative to a FAT for its fit-for-purpose for confirmation of clinical cases of rabies for early response and enhancing rabies surveillance. Results: Among 179 samples examined in this study, there was a concordance in results by the rapid test and FAT in 115 positive samples and 54 negative samples. Test results were discordant in 10 samples which were positive by FAT, but negative (false negative) by rapid kit. The rapid test kit showed a sensitivity of 92% (95% CI: 85.9 – 95.6) and specificity of 100% (95% CI: 93.4 – 100) using FAT as the reference standard. The positive and negative predictive values were found to be 100% (95% CI:96.7 – 100) and 84.4% (95% CI: 73.6 – 91.3), respectively. Overall, there was 94.4% (95% CI: 90 – 96.9) test agreement between rapid test and FAT (Kappa value = 0.874) with a positive percent agreement and negative percent agreement of 92 and 100%, respectively. Conclusions: Our finding demonstrated that the rapid test kit (BioNote) can be used for rabies surveillance and confirming clinical case of rabies in animals for making rapid decisions particularly controlling rabies outbreaks in resource poor settings.

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A Targeted Survey for Scrapie in Jos Plateau State, Nigeria

Journal of Veterinary Medicine ◽

10.1155/2013/841978 ◽

2013 ◽

Vol 2013 ◽

pp. 1-5

Author(s):

O. O. Nwankiti ◽

E. I. Ikeh ◽

O. A. Arowolo ◽

A. J. Nwankiti ◽

M. O. Odugbo ◽

...

Keyword(s):

Fluorescent Antibody ◽

Fatal Outcome ◽

Small Ruminants ◽

Rapid Test ◽

Antibody Test ◽

Economic Losses ◽

Sheep And Goats ◽

Test Kit ◽

Casualty Slaughter ◽

Plateau State

Scrapie, a disease of sheep and goats with a progressive course and fatal outcome, has not been identified in Nigeria. Anecdotal scrapie reports by livestock workers abound. Livestock diseases like scrapie form huddles in livestock economics of countries. For 8 months we surveyed for scrapie targeting emergency/casualty slaughter sheep and goats in Jos, Nigeria. We clinically examined 510 sheep and 608 goats of local breeds, aged from 12 months to 5 years. In total 31 (5.10%) goats and no sheep were clinically suspicious for scrapie. Caudal brainstem tissues of suspect animals collected postmortem were analyzed for the disease specific form of the prion protein, PrPSc, using Bio-Rad’s TeSeE ELISA rapid test kit. No sample was positive for scrapie. Fluorescent antibody test for rabies and H&E staining on samples were carried out for differential diagnosis. These showed no pathological lesions indicative for neurological disease. While our findings do not exclude the presence of scrapie in Jos, we demonstrate that targeted sampling of small ruminants for neuroinfectious disease is feasible in developing countries, pointing to the possibility of implementing such a monitoring scheme in Nigeria to prevent economic losses in small ruminant livestock as scrapie caveats from endemic countries have shown.

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Evaluation of Enzyme Linked Immuno-Sorbent Assay and Rapid Immuno-Diagnostic Test for Rabies Antigen Detection in Archived Dog Brain Tissues

Folia Veterinaria ◽

10.2478/fv-2018-0003 ◽

2018 ◽

Vol 62 (1) ◽

pp. 18-24

Author(s):

G. R. Okoh ◽

H. M. Kazeem ◽

G. S. N. Kia ◽

S. Mailafia

Keyword(s):

Gold Standard ◽

Fluorescent Antibody ◽

Antibody Test ◽

Epidemiological Studies ◽

Antigen Detection ◽

Diagnostic Laboratory ◽

Dog Brain ◽

Kappa Value ◽

Rabies Diagnosis ◽

Brain Tissues

Abstract Rabies urgently requires strengthening of new and existing diagnostic methodology in order to overcome the threat it poses. We evaluated the Enzyme Linked Immuno-Sorbent Assay (ELISA) and the Rapid Immunodiagnostic Test (RIDT) in detecting rabies viral antigens, comparing both tests with the Direct Fluorescent Antibody Test (DFAT) which is the gold standard in rabies diagnosis. Fifty dog brain tissues collected from the archives of the Central Diagnostic Laboratory, National Veterinary Research Institute, Vom, Nigeria, were utilized for this study. ELISA performed better than RIDT and recorded equivalent result with DFAT as compared with RIDT. There was a 96 % agreement between ELISA and DFAT for rabies antigen detection (concordance coefficient 78 % : 95 % C. I. 0.6366 to 0.8654) while there was a 54 % agreement between RIDT and DFAT (concordance coefficient 17 % : 95 % C. I. 0.05138—0.2752). Compared to DFAT, the sensitivities of ELISA and RIDT were 95.5 % and 47.6 %, respectively, and the specificities of ELISA and RIDT were 100 % and 87.5 % respectively. The simple Cohen’s kappa coefficient for ELISA related to the DFAT was found to be 0.834 (95 % C. I. 0.613—1.0). For RIDT, the Kappa value was 0.170 (95 % C. I. 0.003—0.337). The ELISA is as reliable a diagnostic method as the DFAT which is the gold standard for rabies diagnosis. It has an advantage of being able to analyse large number of samples at the same time, making it more suitable for epidemiological studies and for laboratories that cannot perform the DFAT. The unsatisfactory result of RIDT in this study reiterates the need to perform an adequate test validation before it can be used in the laboratory for rabies diagnosis.

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Comparison of a Clinic-Based ELISA Test Kit with the Immunofluorescence Antibody Test for AssayingLeishmania infantumAntibodies in Dogs

BioMed Research International ◽

10.1155/2013/249010 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 7

Author(s):

Daniela Proverbio ◽

Eva Spada ◽

Luciana Baggiani ◽

Giada Bagnagatti De Giorgi ◽

Roberta Perego

Keyword(s):

Roc Curve ◽

Fluorescent Antibody ◽

Antibody Test ◽

Elisa Test ◽

Standard Test ◽

Confirmatory Test ◽

Canine Leishmaniosis ◽

Igg Antibodies ◽

Serum Samples ◽

Test Kit

This study compares a rapid Immunospecific Kalazar Canine Rapid Spot IF with the gold standard test (indirect fluorescent antibody test (IFAT)) for detection ofLeishmania infantumspecific IgG serum antibodies in naturally exposed dogs. Serum samples were obtained from 89 healthy dogs and dogs affected by canine leishmaniosis (CanL). IgG-IFAT titers ≥80 were considered positive. Anti-L. infantumIgG antibodies were found in 54 samples with titers ranging from 1 : 80 to 1 : 5120. The performance of the rapid Immunospecific Kalazar was evaluated using a ROC curve. The area under the ROC curve of 0.957 was significantly different from 0.5 (), and therefore it can be concluded that the rapid Immunospecific Kalazar has the ability to distinguish canine sera with and withoutL. infantumIgG. The best performance of the test was at a cutoff >0 (sensitivity 92.6%, specificity 97%). The test can be used for disease screening if the cutoff is >0 (highest sensitivity, 92.6%) and is recommended as confirmatory test for the presence ofL. infantumIgG antibodies if the cutoff is set >2 (highest specificity, 100%).

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Evaluation of a rapid immunodiagnostic test kit for detection of African lyssaviruses from brain material

Onderstepoort Journal of Veterinary Research ◽

10.4102/ojvr.v76i2.50 ◽

2009 ◽

Vol 76 (2) ◽

Cited By ~ 13

Author(s):

W. Markotter ◽

D. York ◽

C.T. Sabeta ◽

W. Shumba ◽

G. Zulu ◽

...

Keyword(s):

Mouse Brain ◽

Fluorescent Antibody ◽

Antibody Test ◽

Suckling Mouse ◽

Phylogenetic Groups ◽

Test Kit ◽

Brain Material ◽

Selection Of

Rapid immunodiagnostic test kit was evaluated against a selection of isolates of lyssavirus genotypes occurring in Africa. The test was carried out in parallel comparison with the fluorescent antibody test (FAT) and isolates representing previously established phylogenetic groups from each genotype were included. The specificity of the rapid immunodiagnostic test compared favourably with the FAT and was found to detect all representatives of genotypes 1, 2, 3 and 4 in brain samples of either field cases or suckling mouse brain inoculates.

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Comparison of Weil Felix Test and ELISA with the Gold Standard IFA for the Diagnosis of Scrub Typhus in Clinically Suspected Cases of Scrub Typhus at a Tertiary Care Hospital in Tamil Nadu

Journal of Evidence Based Medicine and Healthcare ◽

10.18410/jebmh/2021/325 ◽

2021 ◽

Vol 8 (21) ◽

pp. 1722-1725

Author(s):

Anisha Elizabeth Jacob ◽

Marina Thomas ◽

v Appalaraju

Keyword(s):

Gold Standard ◽

Tamil Nadu ◽

Scrub Typhus ◽

Fluorescent Antibody ◽

Tertiary Care ◽

Antibody Test ◽

Enzyme Linked Immunosorbent Assay ◽

Care Hospital ◽

Serological Tests ◽

Cross Sectional

BACKGROUND Scrub typhus is a febrile disease, the clinical diagnosis of which is difficult due to its vague symptoms. Scrub typhus is diagnosed mainly via serological tests. Sensitivity of Weil Felix was found to be poor, but the specificity of Weil Felix was variable in different studies. Enzyme linked immunosorbent assay (ELISA) IgM is known to be a sensitive test, but its specificity was variable in different studies. Therefore, in this study we have compared these two tests with the gold standard IFA. METHODS The study was performed as a cross-sectional study. Among the suspected scrub typhus cases, fifty consecutive IFA scrub typhus positive and fifty consecutive IFA negative samples were taken for comparison of Weil Felix and ELISA tests. The indirect fluorescent antibody test (IFA) was taken as the gold standard. RESULTS The sensitivity of ELISA and Weil Felix at a titre of 1 : 160 was found to be 96 % and 40 % respectively. The specificity of ELISA and Weil Felix at 1 : 160 and was found to be 88 % and 94 % respectively. CONCLUSIONS Scrub typhus should be kept in mind as a possible diagnosis in acute febrile illnesses. Weil - Felix was found to have a good specificity but low sensitivity. Hence, if the results by Weil Felix are negative, scrub typhus cannot be ruled out and may require further testing. ELISA showed good sensitivity making it a preferable screening test but is not highly specific and confirmation with IFA may be required when feasible. KEYWORDS Scrub Typhus, ELISA, Weil Felix, IFA, Laboratory Diagnosis

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