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Acta Tropica Jul 2022Glanders and brucellosis are zoonotic infectious diseases that affect equids in several countries worldwide. On Marajó Island (Amazon region of Brazil), Marajoara and...
Glanders and brucellosis are zoonotic infectious diseases that affect equids in several countries worldwide. On Marajó Island (Amazon region of Brazil), Marajoara and Puruca horses, which are well adapted to the climatic and territorial adversities of the region, play a fundamental role in the local economy and in the sociocultural lives of the population. However, these animals have undergone a drastic reduction in number, markedly due to precarious veterinary care, unknown causes of morbidity and mortality, and disordered crossing with other breeds introduced to the island. Thus, this study aimed to investigate the occurrence of glanders and brucellosis in equids on a property located in the municipality of Soure, Marajó Island (Brazil). Serum samples were collected from 388 animals (357 horses and 31 mules), maintained in an extensive breeding system, in a property that was also extensively breeding buffaloes, goats, and sheep, with contact among species. The sera were tested for glanders using an indirect ELISA (ELISAi), and the results were confirmed by immunoblotting. The diagnosis of brucellosis was made using the Rose Bengal test (RBT) and confirmed through the Serum Agglutination test (SAT) and 2-mercaptoethanol test. In the case of glanders, 2.31% (9/388) of animals were positive in ELISAi test, of which eight had results confirmed by immunoblotting, representing 2.06% seropositivity in the entire herd. For brucellosis, serum samples from 6.7% (26/388) horses were reactive in the RBT, of which 4.12% (18/388) had a titer ≥50 and 2.06% (8/388) had a titer ≥100 in the SAT. This is the first study to report the occurrence of glanders and equine brucellosis in the municipality of Soure/Marajó Island. Monitoring the occurrence of such diseases is extremely important since they affect the herds economically and zootechnically, in addition to their high zoonotic potential. The number of animals sampled in this study, as well as the way they are raised and managed, is representative of the total equid population of the island. These results, combined with previous studies on buffaloes, indicate that these diseases are endemic in the Marajo Island.
Topics: Agglutination Tests; Animals; Antibodies, Bacterial; Brazil; Brucellosis; Buffaloes; Glanders; Horses; Rose Bengal; Sheep; Zoonoses
PubMed: 35346668
DOI: 10.1016/j.actatropica.2022.106429 -
Pathogens (Basel, Switzerland) Mar 2022A One Health approach to the epidemiology, management, surveillance, and control of leptospirosis relies on accessible and accurate diagnostics that can be applied to... (Review)
Review
A One Health approach to the epidemiology, management, surveillance, and control of leptospirosis relies on accessible and accurate diagnostics that can be applied to humans and companion animals and livestock. Diagnosis should be multifaceted and take into account exposure risk, clinical presentation, and multiple direct and/or indirect diagnostic approaches. Methods of direct detection of spp. include culture, histopathology and immunostaining of tissues or clinical specimens, and nucleic acid amplification tests (NAATs). Indirect serologic methods to detect leptospiral antibodies include the microscopic agglutination test (MAT), the enzyme-linked immunosorbent assay (ELISA), and lateral flow methods. Rapid diagnostics that can be applied at the point-of-care; NAAT and lateral flow serologic tests are essential for management of acute infection and control of outbreaks. Culture is essential to an understanding of regional knowledge of circulating strains, and we discuss recent improvements in methods for cultivation, genomic sequencing, and serotyping. We review the limitations of NAATs, MAT, and other diagnostic approaches in the context of our expanding understanding of the diversity of pathogenic spp. Novel approaches are needed, such as loop mediated isothermal amplification (LAMP) and clustered regularly interspaced short palindromic repeats (CRISPR)-based approaches to leptospiral nucleic acid detection.
PubMed: 35456070
DOI: 10.3390/pathogens11040395 -
Zoonoses and Public Health Jun 2022Despite public concern on the role of free-roaming cats as reservoirs of zoonotic agents, little is known about the influence of urban and peri-urban landscapes on the...
Despite public concern on the role of free-roaming cats as reservoirs of zoonotic agents, little is known about the influence of urban and peri-urban landscapes on the exposure risk. We evaluated the seroprevalence of three zoonotic agents (Chlamydia felis, Coxiella burnetii and Toxoplasma gondii) in domestic cats (Felis catus). Two hundred and ninety-one free-roaming cats were trapped in Murcia municipality (Southeast Spain), and their sera were tested for specific antibodies against T. gondii using a modified agglutination test (MAT), and for C. felis, C. burnetii and feline immunodeficiency virus (FIV) antibodies with ELISA technique. Pathogen seroprevalence at 95% CI was calculated for each sex and age category (up to and over 12 months) and compared with a chi-squared test. The role of human population density and urban landscape characteristics on the risk of pathogen exposure in the cat population was explored using generalized linear models. Seropositivity against a single pathogen was found in 60% of the cats, while 19% was seropositive for two or three pathogens. Seroprevalence of C. felis was 8% (CI : 5-11), 37% (CI : 31-42) for C. burnetii and 42% (CI : 36-47) for T. gondii. In addition to these three pathogens, FIV seropositivity was low (1%, CI : -0.1 to 2) and adult cats were more likely to be seropositive to C. burnetii than young individuals (OR: 2.3, CI : 1.2-4.2). No sex or age class differences in seroprevalence were observed for the rest of the pathogens. Seropositivity was correlated with water surface areas for C. felis, and not with crop areas. Coxiella burnetii seropositivity was correlated with the percentage of urban areas (continuous with only buildings and discontinuous, that include buildings, parks, and pedestrian and urban green areas), human population size and peri-urban areas with shrubs, and not correlated with other agricultural landscapes (orchards and crop areas). However, the seroprevalence of T. gondii was only associated with agricultural landscapes such as orchards. The detection of hotspot areas of high pathogen exposure risk is the basis for municipal services to implement surveillance and risk factor control campaigns in specific-risk areas, including (a) efficient health management of urban cat colonies by geographical location, population census and health status monitoring of the components of each cat colony, (b) improvement of hygiene and sanitary conditions at the feeding points of the cat colony and (c) free-roaming cat trapping for health monitoring and, in the long term, to know the evolution of the health status of their populations.
Topics: Agglutination Tests; Animals; Antibodies, Protozoan; Cat Diseases; Cats; Chlamydia; Risk Factors; Seroepidemiologic Studies; Toxoplasma; Toxoplasmosis, Animal
PubMed: 35129882
DOI: 10.1111/zph.12919 -
Journal of Virological Methods Sep 2023To detect the antibody against fowl adenovirus serotype 4 (FAdV-4) in clinical practice, the latex agglutination test (LAT) was developed by using the Fiber-2 protein of...
To detect the antibody against fowl adenovirus serotype 4 (FAdV-4) in clinical practice, the latex agglutination test (LAT) was developed by using the Fiber-2 protein of FAdV-4 as an antigen bound to sensitized latex microspheres. The concentration, time, and temperature of sensitization latex microspheres by the Fiber-2 protein were studied and optimized; the specificity, sensitivity, and repeatability of LAT were tested; and the method developed in the study was applied. The results showed that the optimum sensitization concentration of Fiber-2 protein was 0.8 mg/mL, the time was 120 min, and the temperature was 37 ℃. Except for antiserum against FAdV-4 and FAdV-10, LAT developed in the study could not agglutinate antisera against FAdV-1, FAdV-2, FAdV-3, FAdV-4, FAdV-5, FAdV-6, FAdV-8a, FAdV-8b, FAdV-11, Newcastle disease virus, infectious bronchitis virus, egg drop syndrome virus and Clostridium perfringens. Compared with the commercial FAdV-4 ELISA Kit, the titers in 21 clinical samples were low when tested by the developed LAT method, but there was no significant difference. The coefficients of variation among different batches and the same batch of latex-sensitized particles were between 0 % and 13.3 % and 0-8.7 %, respectively. The critical value of immune protective antibody against FAdV-4 was 2, and the titers in 40.9 % of clinical samples were higher than the immune critical point. The results showed that the Fiber-2-based LAT developed in the study has the characteristics of high specificity, sensitivity and repeatability, has the advantages of free equipment, long shelf life, and fast and easy operation, and is an effective and convenient method for serological diagnosis of FAdV-4 infection and evaluating the efficacy of vaccines.
Topics: Animals; Serogroup; Aviadenovirus; Adenoviridae Infections; Latex Fixation Tests; Antibodies, Viral; Chickens; Adenoviridae; Poultry Diseases
PubMed: 37290574
DOI: 10.1016/j.jviromet.2023.114760 -
Transfusion and Apheresis Science :... Oct 2023Several autoimmune disorders have been reported to be related with COVID infection. In continuation to these autoimmune phenomenon, autoimmune hemolytic anaemia (AIHA)... (Observational Study)
Observational Study
BACKGROUND
Several autoimmune disorders have been reported to be related with COVID infection. In continuation to these autoimmune phenomenon, autoimmune hemolytic anaemia (AIHA) also has been noted in COVID infected patients. The aim of the study was to find out the prevalence of red cell alloimmunization, ABO discrepancy and positive direct antiglobulin test (DAT) results in COVID infected patients hospitalised in a tertiary care centre in North India.
METHODOLOGY
This was a retrospective observational study done from July 2020 to June 2021. All symptomatic patients admitted to ICU tested positive for SARS CoV-2 whose blood samples were received in the immunohematology laboratory of department of Transfusion Medicine for determination of blood group and issue of packed red cells, and found to have positive antibody screen, blood group discrepancy and positive DAT results, were included in the study.
RESULTS
A total of 10,568 tests were run, out of which 4437 were for determination of blood group, 5842 were for antibody screen and 289 were for direct antiglobulin test. Included in this study were 146 patients who either had blood group discrepancy, or had a positive antibody screen or had a positive DAT. Out of 115 positive antibody screen, 66 patients had only alloantibodies, 44 patients had only autoantibodies while only 5 patients had both auto as well as alloantibodies. Total number of positive DAT cases was 50 (50/289 = 17.3 %). There were 26 ABO discrepancies (26/4437 =0.58 %) found.
CONCLUSION
Our results also indicate that there is rise in rate of alloimmunization and DAT positivity among COVID patients.
Topics: Humans; Isoantibodies; COVID-19; Anemia, Hemolytic, Autoimmune; Erythrocytes; Coombs Test; Blood Group Antigens
PubMed: 37286441
DOI: 10.1016/j.transci.2023.103729 -
Bulletin of Experimental Biology and... Dec 2021The rapidity, accuracy, and detection abilities of different laboratory methods (tube agglutination test (SAT), indirect ELISA, fluorescence polarization test (FPA), and... (Comparative Study)
Comparative Study
The rapidity, accuracy, and detection abilities of different laboratory methods (tube agglutination test (SAT), indirect ELISA, fluorescence polarization test (FPA), and blood culture methods) to detect Brucella in the laboratory. The study included 95 patients with documented and 42 patients with suspected brucellosis and 56 healthy control subjects. For the tests, the positive rates of Brucella infection detection in the confirmed group were significantly higher than in group with suspected infection (p<0.01) and in healthy controls (p<0.01). There was no significant difference between indirect ELISA and FPA in detecting antibodies to Brucella in acute (χ=0.335), subacute (χ=0.660), and chronic cases (χ=5.332). Among the detection methods, indirect ELISA showed the highest sensitivity (98.9%), specificity (100%), and Youden index (0.989). The sensitivity and specificity of FPA were 96.8 and 96.4%, respectively. In order to easily and rapidly diagnose brucellosis in clinical practice, a combination of detection methods is recommended, in which Brucella antibodies are screened by FPA and then confirmed by indirect ELISA.
Topics: Adolescent; Adult; Aged; Agglutination Tests; Antibodies, Bacterial; Brucella; Brucellosis; Child; Child, Preschool; China; Enzyme-Linked Immunosorbent Assay; Female; Fluorescence Polarization Immunoassay; Humans; Infant; Laboratories; Laboratory Proficiency Testing; Male; Microbiological Techniques; Middle Aged; Reproducibility of Results; Sensitivity and Specificity; Young Adult
PubMed: 34853970
DOI: 10.1007/s10517-021-05367-1 -
Cureus Oct 2021Introduction Early diagnosis and treatment are crucial to reducing the morbidity of patients with enteric fever/typhoid fever. Among the available diagnostic tests, the...
Introduction Early diagnosis and treatment are crucial to reducing the morbidity of patients with enteric fever/typhoid fever. Among the available diagnostic tests, the blood culture is considered a gold standard. However, in most of the developing and resource-limited settings, the diagnosis is made utilizing the traditional Widal test and rapid immunochromatographic test (ICT). This study was aimed to compare the diagnostic value and efficacy of ICT and traditional Widal test in the diagnosis of typhoid fever. Methods A prospective study was conducted, and 40 patients were included in the study. The Widal test and serovar Typhi IgM/IgG immunochromatographic test were performed for all the patients. The Widal is a tube agglutination test, and the rapid ICT utilizes the principle of enzyme-linked immunosorbent assay (ELISA). All the samples were also tested for the presence of antibodies (IgG and IgM) against the . serovar Typhi and the titers against 'O' and 'H' antigens of . serovar Typhi. An antibody titer of 1:80 or more against the 'O' and 'H' antigen was considered positive. Results In the ICT, 24 samples (60%) tested positive for the IgM antibodies, and only 15 samples tested positive and for IgG antibodies. In the Widal test, 27 samples (67.6%) returned positive for antibodies against the . serovar Typhi 'O' antigen. The sensitivity (90% vs 72.73%), specificity (81.25% vs 64%), and accuracy (82.12% vs 64.87%) for the Widal test were found to be more when compared to the ICT. Conclusion The results indicate that the traditional Widal agglutination test is superior to the rapid ICT in the diagnosis of enteric fever. However, both these tests cannot be considered as gold standards for the diagnosis owing to their low positive predictive values.
PubMed: 34754639
DOI: 10.7759/cureus.18474 -
Methods in Molecular Biology (Clifton,... 2020Tachylectin-2, a 27-kDa protein consisting of a five-bladed β-propeller structure, is purified by three steps of chromatography, including dextran sulfate-Sepharose...
Tachylectin-2, a 27-kDa protein consisting of a five-bladed β-propeller structure, is purified by three steps of chromatography, including dextran sulfate-Sepharose CL-6B, CM-Sepharose CL-6B, and Mono S. Three isolectins of tachylectin-2 including tachylectin-2a, -2b, and -2c are purified. These isolectins exhibit hemagglutinating activity against human A-type erythrocytes in a Ca-independent manner with tachylectin-2b showing the highest activity. Tachylectin-2b specifically agglutinates Staphylococcus saprophyticus KD. The tachylectin-2b-mediated hemagglutination is inhibited in the presence of GlcNAc and GalNAc. The association constants for GlcNAc and GalNAc are K = 1.95 × 10 M and K = 1.11 × 10 M, respectively. Ultracentrifugation analysis shows that tachylectin-2b is present in monomer form in solution.
Topics: Acetylgalactosamine; Acetylglucosamine; Agglutination Tests; Animals; Calcium; Chromatography; Erythrocytes; Hemagglutination; Horseshoe Crabs; Humans; Lectins; Protein Isoforms; Protein Multimerization; Staphylococcus saprophyticus
PubMed: 32306338
DOI: 10.1007/978-1-0716-0430-4_30 -
Anales de Pediatria Apr 2021Autoimmune hemolytic anemia (AIHA) is a rare and generally self-limiting disease in children.
INTRODUCTION
Autoimmune hemolytic anemia (AIHA) is a rare and generally self-limiting disease in children.
MATERIAL AND METHODS
A descriptive cross-sectional study was performed in children under 18 years diagnosed with AIHA from January/1997 to July/2019. Clinical variables were collected and AIHA was classified according to the direct antiglobulin test (DAT) in warm AIHA (IgG+/-C3d) and cold AIHA (C3d). Response to treatment and evolution were analyzed.
RESULTS
25 patients were included and 72% were males. The median age at diagnosis was 2 years (range 0.4 to 9). Fever (72%), pallor (68%), jaundice (64%), hepatosplenomegaly and coluria (48%) were the most common presenting symptoms. The median hemoglobin at diagnosis was 5.4 g/dl. DAT was positive in 96%, with detection of IgG antibodies in 76%. A single case presented negative DAT. 20% of the patients associated another cytopenia, one of which was subsequently diagnosed with common variable immunodeficiency. Concomitant viral infection was suspected or documented in 32%. Most of the cases were self-limiting and responded to corticosteroid treatment (72%). Those with partial response (24%), mainly those associated with other cytopenias, required other lines of treatment (rituximab, mycophenolate, immunoglobulins). Complications (32%) and relapses (26%) were detected only in warm AIHA.
CONCLUSIONS
Our case series confirms that AIHA is a very rare disease in childhood. Most cases evolve favorably, although up to a quarter of them require second lines of treatment and, in exceptional cases, they need very aggressive treatments. These latter cases generally correspond to patients who present more than one cytopenia in the course of the disease.
Topics: Anemia, Hemolytic, Autoimmune; Child; Child, Preschool; Coombs Test; Cross-Sectional Studies; Humans; Immunoglobulin G; Infant; Male; Rituximab
PubMed: 32972857
DOI: 10.1016/j.anpedi.2020.07.012 -
Journal of Clinical Laboratory Analysis Mar 2022The laboratory test results and serum-specific antibodies of patients with acute brucellosis initial infection were followed up and analyzed.
BACKGROUND
The laboratory test results and serum-specific antibodies of patients with acute brucellosis initial infection were followed up and analyzed.
METHODS
70 patients in Hohhot City, Inner Mongolia Autonomous Region, with acute brucellosis were followed up for 360 days. Serum samples were collected at 0, 15, 30, 60, 90, 180, and 360 days after diagnosis and analyzed by Rose Bengal plate test (RBPT), colloidal gold test paper (GICA), and test tube agglutination test (SAT). The serum-specific antibodies IgG and IgM were detected.
RESULTS
RBPT results: False negative (-) gradually increased with the extension of the course of disease, with the largest change in 30-60 days after diagnosis, and the constituent ratio increased by 12.9%. GICA results: The false negative increased with the course of disease, and the constituent ratio of false negative was 20.0% after 180 days of diagnosis. SAT results: 1:100 positive showed a ladder like decrease with the increase in the course of disease, and the largest decrease was 90-180 days, with a decrease of 34.3% in the constituent ratio. 360 days after diagnosis, the constituent ratio of positive was only 14.3%. During the follow-up period, the IgG average value fluctuated and the average IgM value decreased.
CONCLUSION
The false-negative results of RBPT, GICA, and SAT increased with the course of disease, and the false-negative rates were higher than 20% after half a year. IgM level is beneficial to the early diagnosis of brucellosis, while IgG level is helpful to the judgment of brucellosis stage.
Topics: Agglutination Tests; Antibodies, Bacterial; Brucellosis; Follow-Up Studies; Humans; Rose Bengal
PubMed: 35137464
DOI: 10.1002/jcla.24205