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International Journal For Parasitology.... Aug 2022is a worldwide-distributed zoonotic protozoan parasite which causes toxoplasmosis and has a significant effect on public health. In the giant panda (), toxoplasmosis...
is a worldwide-distributed zoonotic protozoan parasite which causes toxoplasmosis and has a significant effect on public health. In the giant panda (), toxoplasmosis can cause asymptomatic infections, reproductive disorder and even death, which poses a serious threat to the conservation of this rare protected species. Therefore, serological investigation of is essential to understanding its risk to giant pandas, however, there are no specific testing kits for giant pandas. Previous research has used MAT as the reference method for screening , to investigate this further, this study focused on the agreement comparing of MAT with ELISA and IHA tests for detecting antibodies in 100 blood samples from 55 captive giant pandas in Chengdu, China. The results showed 87.0%, 87.0%, 84.0%, samples were sero-positive for using ELISA (kits a, b, c), respectively, while MAT and IHA tests were 84.0% and 9.0% sero-positive, respectively. There was no significant difference between MAT and the three ELISA kits and these two methods had substantial agreement (0.61 < қ ≤ 0.80). Meanwhile, there was a significant difference ( 0.001) between MAT and IHA, and these two methods had only a slight agreement (қ ≤ 0.20). The relative sensitivity of the ELISA (kits a, b, c) were 89.0%, 91.5% and 95.1%, and the specificity were 86.7%, 80.0% and 80.0%, respectively, which showed these three ELISA kits all had great accuracy. It is suggested that MAT is the recommended test method for primary screening in giant pandas and then verified by ELISA.
PubMed: 35873088
DOI: 10.1016/j.ijppaw.2022.07.001 -
International Journal of Infectious... Apr 2021Leptospirosis is most often diagnosed clinically, and a laboratory test with high diagnostic accuracy is required.
BACKGROUND
Leptospirosis is most often diagnosed clinically, and a laboratory test with high diagnostic accuracy is required.
METHODS
IgM and IgG ELISAs using Leptospira antigens were established and evaluated in relation to the microscopic agglutination test (MAT). Antigen preparation consisted of saprophytic Leptospira biflexa to detect genus-specific antibodies (genus-specific ELISA) and a pool of the five most prevalent Leptospira interrogans serovars in Sri Lanka to detect serovar-specific antibodies (serovar-specific ELISA). IgM and IgG immune responses were studied in severe and mild leptospirosis patients (n = 100 in each group).
RESULTS
The ELISAs showed high repeatability and reproducibility. The serovar-specific IgM-ELISA showed a sensitivity of 80.2% and specificity of 89%; the genus-specific IgM-ELISA showed a sensitivity of 83.3% and specificity of 91%. The serovar- and genus-specific IgG-ELISAs showed sensitivities of 73.3% and 81.7%, respectively, and specificities of 83.3% and 83.3%, respectively. The commercial IgM-ELISA showed a sensitivity of 79.2% and specificity of 93%. The commercial IgG-ELISA showed a sensitivity of 50% and specificity of 96.7%. IgM levels observed in mild and severe leptospirosis patients were significantly higher than in the healthy control group, with mean absorbance values of 0.770, 0.778, and 0.163, respectively. Severe leptospirosis patients had significantly higher mean anti-leptospiral IgG levels compared to both mild leptospirosis patients and healthy control group subjects (0.643, 0.358, and 0.116, respectively; ANOVA, p < 0.001). The presence of anti-leptospiral IgG above an optical density of 0.643 at 1:100 could predict a high risk of severe disease.
CONCLUSION
The serovar-specific in-house ELISA could be used for the laboratory diagnosis of leptospirosis in endemic settings. The high levels of anti-leptospiral IgG observed suggest its value as a predictor of disease severity.
Topics: Agglutination Tests; Antibodies, Bacterial; Antigens, Bacterial; Enzyme-Linked Immunosorbent Assay; Female; Humans; Immunoglobulin G; Immunoglobulin M; Leptospira interrogans; Leptospirosis; Reproducibility of Results; Sensitivity and Specificity; Serologic Tests; Sri Lanka
PubMed: 33556609
DOI: 10.1016/j.ijid.2021.01.074 -
International Journal For Parasitology.... Aug 2020is considered a disease risk for many native Australian species. Feral cats are the key definitive host of in Australia and therefore, investigating the epidemiology...
Comparison of the modified agglutination test and real-time PCR for detection of exposure in feral cats from Phillip Island, Australia, and risk factors associated with infection.
is considered a disease risk for many native Australian species. Feral cats are the key definitive host of in Australia and therefore, investigating the epidemiology of in cat populations is essential to understanding the risk posed to wildlife. Test sensitivity and specificity are poorly defined for diagnostic tests targeting in cats and there is a need for validated techniques. This study focused on the feral cat population on Phillip Island, Victoria, Australia. We compared a novel real-time PCR (qPCR) protocol to the modified agglutination test (MAT) and used a Bayesian latent class modelling approach to assess the diagnostic parameters of each assay and estimate the true prevalence of in feral cats. In addition, we performed multivariable logistic regression to determine risk factors associated with infection in cats. Overall prevalence by qPCR and MAT was 79.5% (95% confidence interval 72.6-85.0) and 91.8% (84.6-95.8), respectively. Bayesian modelling estimated the sensitivity and specificity of the MAT as 96.2% (95% credible interval 91.8-98.8) and 82.1% (64.9-93.6), and qPCR as 90.1% (83.6-95.5) and 96.0% (82.1-99.8), respectively. True prevalence of infection in feral cats on Phillip Island was estimated as 90.3% (83.2-95.1). Multivariable logistic regression analysis indicated that infection was positively associated with weight and this effect was modified by season. Cats trapped in winter had a high probability of infection, regardless of weight. The present study suggests qPCR applied to tissue is a highly sensitive, specific and logistically feasible tool for testing in feral cat populations. Additionally, infection is highly prevalent in feral cats on Phillip Island, which may have significant impacts on endemic and introduced marsupial populations.
PubMed: 32547918
DOI: 10.1016/j.ijppaw.2020.05.006 -
PLoS Neglected Tropical Diseases Jun 2022Leptospirosis is among the most important zoonotic diseases in (sub-)tropical countries. The research objective was to evaluate the accuracy of the Serion IgM ELISA...
Comparison of the Serion IgM ELISA and Microscopic Agglutination Test for diagnosis of Leptospira spp. infections in sera from different geographical origins and estimation of Leptospira seroprevalence in the Wiwa indigenous population from Colombia.
Leptospirosis is among the most important zoonotic diseases in (sub-)tropical countries. The research objective was to evaluate the accuracy of the Serion IgM ELISA EST125M against the Microscopic Agglutination Test (MAT = imperfect reference test); to assess its ability to diagnose acute leptospirosis infections and to detect previous exposure to leptospires in an endemic setting. In addition, to estimate the overall Leptospira spp. seroprevalence in the Wiwa indigenous population in North-East Colombia. We analysed serum samples from confirmed leptospirosis patients from the Netherlands (N = 14), blood donor sera from Switzerland (N = 20), and sera from a cross-sectional study in Colombia (N = 321). All leptospirosis ELISA-positive, and a random of negative samples from Colombia were tested by the MAT for confirmation. The ELISA performed with a sensitivity of 100% (95% CI 77% - 100%) and a specificity of 100% (95% CI 83% - 100%) based on MAT confirmed Leptospira spp. positive and negative samples. In the cross-sectional study in Colombia, the ELISA performed with a sensitivity of 100% (95% CI 2-100%) and a specificity of 21% (95% CI 15-28%). Assuming a 5% Leptospira spp. seroprevalence in this population, the positive predictive value was 6% and the negative predictive value 100%. The Leptospira spp. seroprevalence in the Wiwas tested by the ELISA was 39%; however, by MAT only 0.3%. The ELISA is suitable to diagnose leptospirosis in acutely ill patients in Europe several days after onset of disease. For cross-sectional studies it is not recommended due to its low specificity. Despite the evidence of a high leptospirosis prevalence in other study areas and populations in Colombia, the Wiwa do not seem to be highly exposed to Leptospira spp.. Nevertheless, leptospirosis should be considered and tested in patients presenting with febrile illness.
Topics: Agglutination Tests; Antibodies, Bacterial; Colombia; Cross-Sectional Studies; Enzyme-Linked Immunosorbent Assay; Humans; Immunoglobulin M; Indigenous Peoples; Leptospira; Leptospirosis; Sensitivity and Specificity; Seroepidemiologic Studies
PubMed: 35666764
DOI: 10.1371/journal.pntd.0009876 -
Iranian Journal of Veterinary Research 2022Leptospirosis is considered to be an economically important disease in bovine. The disease burden is not appropriately monitored due to cumbersome serological tests that...
BACKGROUND
Leptospirosis is considered to be an economically important disease in bovine. The disease burden is not appropriately monitored due to cumbersome serological tests that could be performed only in established laboratories. This warrants the development of a field level rapid diagnostic test.
AIMS
The study aimed to develop a lateral flow assay (LFA)-based pen-side diagnostic test to detect antibodies to .
METHODS
LFA strip was prepared with the heat extracted antigen from serovar Pomona. To assess the performance of the developed LFA, a total of 300 bovine serum samples with their clinical histories were used and the initial screening for antibodies was performed by the standard microscopic agglutination test (MAT). The sensitivity, specificity, and agreement (kappa value) were calculated between developed LFA and MAT. The stability of LFA was evaluated on days 30, 60, 90, and 120.
RESULTS
Out of 300 samples tested, 225 were positive, and 75 were negative on MAT and 208 were positive, and 92 were negative on LFA. The developed LFA had a sensitivity of 90.7% and a specificity of 94.7%. The results of the assay were substantially in agreement with MAT, with a kappa value of 0.79. The LFA strips were stable for 120 days at 4°C.
CONCLUSION
A Lateral flow assay-based rapid pen-side test was developed and its utility to diagnose bovine leptospirosis was evaluated.
PubMed: 35782352
DOI: 10.22099/IJVR.2021.41151.5974 -
PLoS Neglected Tropical Diseases Feb 2023This study aims to evaluate the efficacy of the standard agglutination test (SAT), the Brucellacapt test and enzyme-linked immunosorbent assay (ELISA) in clinical...
BACKGROUND
This study aims to evaluate the efficacy of the standard agglutination test (SAT), the Brucellacapt test and enzyme-linked immunosorbent assay (ELISA) in clinical specimens collected from patients with suspected brucellosis.
METHODS
A prospective study was conducted from December 2020 to December 2021. Brucellosis was diagnosed on the basis of clinical evidence, and confirmed by isolation of Brucella or a four-fold rise in SAT titer. All samples were tested by the SAT, ELISA and the Brucellacapt test. Titers ≥1:100 were considered as SAT positive; ELISA was considered positive when an index greater than 11 was detected, while titers ≥1/160 indicated positivity on the Brucellacapt test. The specificity, sensitivity, and positive (PPVs) and negative predictive values (NPVs) of the three different methods were calculated.
RESULTS
A total of 149 samples were collected from patients with suspected brucellosis. The sensitivities for the SAT, IgG, and IgM detection were 74.42%, 88.37% and 74.42%, respectively. The specificities were 95.24%, 93.65%, and 88.89%, respectively. The simultaneous measurement of IgG and IgM improved the sensitivity (98.84%) but reduced the specificity (84.13%) compared to each antibody test separately. The Brucellacapt test had excellent specificity (100%) and a high PPV (100%); however, the sensitivity and NPV were 88.37% and 86.30%, respectively. The combination of IgG detection by ELISA and the Brucellacapt test had excellent diagnostic performance, with 98.84% sensitivity and 93.65% specificity.
CONCLUSION
This study showed that the simultaneous performance of IgG detection by ELISA and the Brucellacapt test has the potential to overcome the current limitations of detection.
Topics: Humans; Prospective Studies; Antibodies, Bacterial; Brucellosis; Agglutination Tests; Enzyme-Linked Immunosorbent Assay; Immunoglobulin G; Immunoglobulin M; Sensitivity and Specificity
PubMed: 36802393
DOI: 10.1371/journal.pntd.0011131 -
ACS Synthetic Biology Sep 2022Malaria, a disease caused by the parasite carried by mosquitoes, is commonly diagnosed by microscopy of peripheral blood smears and with rapid diagnostic tests. Both...
Malaria, a disease caused by the parasite carried by mosquitoes, is commonly diagnosed by microscopy of peripheral blood smears and with rapid diagnostic tests. Both methods show limited detection of low parasitemia that may maintain transmission and hinder malaria elimination. We have developed a novel agglutination assay in which modified cells act as antigen-displaying bead-like particles to capture malaria antibodies. The Epidermal Growth Factor-1 like domain (EGF1) of the merozoite surface protein-1 (PfMSP-1) was displayed on the yeast surface and shown to be capable of binding antimalaria antibodies. Mixed with a second yeast strain displaying the Z domain of Protein A from and allowed to settle in a round-bottomed well, the yeast produce a visually distinctive agglutination test result: a tight "button" at a low level of malarial antibodies, and a diffuse "sheet" when higher antibody levels are present. Positive agglutination results were observed in malaria-positive human serum to a serum dilution of 1:100 to 1:125. Since the yeast cells are inexpensive to produce, the test may be amenable to local production in regions seeking malaria surveillance information to guide their elimination programs.
Topics: Agglutination; Agglutination Tests; Animals; Antibodies, Protozoan; EGF Family of Proteins; Humans; Malaria; Malaria, Falciparum; Merozoite Surface Protein 1; Saccharomyces cerevisiae
PubMed: 35861604
DOI: 10.1021/acssynbio.2c00160 -
Journal of Infection and Public Health Mar 2023Aim to investigate the brucella culture characteristics, diagnosis methods, and clinical characteristics, to provide the laboratory with diagnostic methods and...
OBJECTIVE
Aim to investigate the brucella culture characteristics, diagnosis methods, and clinical characteristics, to provide the laboratory with diagnostic methods and prevention and treatment for brucellosis.
METHODS
Data of 328 cases of brucellosis from 2012 to 2022 was analyzed, retrospectively. The bacterial culture characteristics, the clinical diagnostic methods, and the complications were analyzed respectively. The infection biomarkers of the brucellosis were analyzed by Receiver operating characteristic curve ROC.
RESULTS
Among the 328 brucellosis, 78.96 % of cases were men, the median age of the patients was (45.21±13.49) years and the annual incidence in our region was 67/100 000 per year. The diagnostic methods included pathogenic bacteria culture, serological diagnosis, and suspect case were 24.39 %, 47.56 %, and 28.05 %, respectively, sensitivity of combined detection Standard agglutination test (SAT) and the Rose Bengal test (RBT) is 96.2 %. In our work, 80 cases of brucellosis were diagnosed by a bacterial culture which were been identified as Brucella melitensis, blood culture was the main method (78.75 %) and the average positive alarm time was 80.74 (21.6-129) h and all of them were detected in aerobic bottles, followed by synovial fluid, bone marrow, lumbar spine, and joint tissue, puncture fluid and ascites culture which were 6.25 %, 3.75 %, 5.00 %, 5.00 % and 1.25 % respectively. The brucellosis with complications was lumbar spine lesions at 41.46 % cervical spine lesions at 4.60 % and knee joint lesions at 12.8 % and another osteoarthritis. The in-hospital mortality rate of the patients was 0.91 % and all of them were meningitis patients. ROC analysis indicated CRP had high sensitivity and specificity for brucellosis, and when CRP was 1.23mg/ml, the sensitivity and specificity were 0.727 and 0.718 respectively, and the U test also indicated CRP had a significant difference, Z=5.054, p <0.001.
CONCLUSIONS
Brucellosis is frequently morbidity in 40 + age men, which has been diagnosed by aerobic blood culture, generally bacterial culture, RBT and SAT, epidemiological, and commonly with complications of spine and arthropathy.
Topics: Adult; Female; Humans; Male; Middle Aged; Agglutination Tests; Antibodies, Bacterial; Brucella melitensis; Brucellosis; Retrospective Studies; Rose Bengal; Sensitivity and Specificity
PubMed: 36641837
DOI: 10.1016/j.jiph.2023.01.002 -
BMC Infectious Diseases Mar 2021Recent seroepidemiological studies have suggested that tularemia could be an endemic bacterial zoonosis in Iran.
BACKGROUND
Recent seroepidemiological studies have suggested that tularemia could be an endemic bacterial zoonosis in Iran.
METHODS
From January 2016 to June 2018, disease cases characterized by fever, cervical lymphadenopathy and ocular involvement were reported in Youzband Village of Kaleybar County, in the East Azerbaijan Province, northwestern Iran. Diagnostic tests included Francisella tularensis serology (including tube agglutination test and ELISA), PCR, and culture.
RESULTS
Among 11 examined case-patients, the tularemia tube agglutination test was positive in ten and borderline in one. PCR detected the F. tularensis ISFtu2 elements and fopA gene in one rodent and a spring water sample from the same geographic area.
CONCLUSIONS
Based on the clinical manifestations of the disease suggesting an oropharyngeal form of tularemia, serology results in case patients, and F. tularensis detection in the local fauna and aquatic environment, the water supply of the village was the likely source of the tularemia outbreak. Intervention such as dredging and chlorination of the main water storage tank of the village and training of villagers and health care workers in preventive measures and treatment of the illness helped control the infection.
Topics: Adolescent; Adult; Aged; Agglutination Tests; Animals; Bacterial Outer Membrane Proteins; Child; Child, Preschool; DNA, Bacterial; Female; Francisella tularensis; Fresh Water; Humans; Iran; Male; Mice; Polymerase Chain Reaction; Tularemia
PubMed: 33789598
DOI: 10.1186/s12879-021-06004-y -
Transfusion Oct 2023Warm antibody-mediated autoimmune hemolysis (WAIHA) is most often due to immunoglobulin G (IgG) antibodies and is detected by direct antiglobulin test (DAT). However,...
INTRODUCTION
Warm antibody-mediated autoimmune hemolysis (WAIHA) is most often due to immunoglobulin G (IgG) antibodies and is detected by direct antiglobulin test (DAT). However, about 10% cases of hemolytic anemia are DAT negative. Herein, we describe a patient with DAT-negative hemolytic anemia due to an anti-IgA antibody. We investigate if isolated IgA can promote erythrophagocytosis.
METHODS
We isolated patient and control IgA on Jacalin agarose. Isolated IgA was used to sensitize healthy ABO/Rh-matched donor red blood cells (RBC). Antibody binding was examined by flowcytometry. The effect of IgA on erythrophagocytosis was evaluated using Macrophage colony stimulating factor 1 (M-CSF)-differentiated autologous macrophages by Giemsa staining and immunofluorescence microscopy.
RESULTS
We show that isolated IgA from the serum can bind to red cells. In addition, RBCs were phagocytosed efficiently by autologous macrophages in the presence of patient IgA.
CONCLUSION
Our results show that IgA antibodies are capable of inducing erythrophagocytosis like IgG antibodies in the absence of complement fixation.
Topics: Humans; Anemia, Hemolytic, Autoimmune; Immunoglobulin A; Hemolysis; Autoantibodies; Erythrocytes; Immunoglobulin G; Lymphohistiocytosis, Hemophagocytic; Coombs Test
PubMed: 37668082
DOI: 10.1111/trf.17532