scholarly journals Serological and molecular investigation of human brucellosis in participants of Famenin brucellosis cohort study, Hamadan, Iran

2021 ◽  
Author(s):  
Maryam Adabi ◽  
Manoochehr Karami ◽  
Fariba Keramat ◽  
Mohammad Yousef Alikhani ◽  
Somaye Bakhtiari
Keyword(s):  
Target Gene ◽  
Brucella Melitensis ◽  
Serological Test ◽  
Human Brucellosis ◽  
Intracellular Pathogen ◽  
Pcr Assay ◽  
Specific Primers ◽  
Serological Tests ◽  
Molecular Investigation ◽  
Investigation Technique

Background and Objectives: Brucella is an intracellular pathogen that causes brucellosis in humans and animals. This study aimed to assess the results of brucellosis seroprevalence among participants of the Famenin brucellosis cohort with molecular investigation technique and determine Brucella-approved species. Materials and Methods: Following the first phase of the Famenin brucellosis cohort in 2016 which investigated the seroprevalence of brucellosis among 2367 participants in Famenin city, a total of 575 people including all seropositive and some seronegative people were examined again by wright serological tests in 2019. The PCR assay was accomplished on all cases that have wright titers ≥ 1/20 for tracing Brucella DNA using BCSP31 target gene and IS711 locus. Results: Out of 575 studied cases, 145 people had wright titers ≥ 1/20. The PCR reactions of these 145 blood samples were positive in 63/145 (43.44%) tested samples using primers (B4/B5) for Brucella genus detection. In the second PCR assay using specific-primers for Brucella abortus and Brucella melitensis, 18/63 (28.57%) of the samples were diagnosed as B. abortus, and 18/63 (28.57%) were diagnosed as B. melitensis. Conclusion: In this study, using the selected specific genes for the diagnosis of Brucella in the genus and species levels, the PCR technique was evaluated as a promising method for the rapid and safe detection of brucellosis besides the serological test for more accurate detection of brucellosis especially in cases that are not definitive.

scholarly journals Incidental Laboratory Identification of Brucella melitensis in a case with Pancytopenia

2021 ◽  
Vol 10 (10) ◽  
pp. 193-198
Author(s):  
Mahalakshmi Kumaresan Lakshmi Shanmugam ◽  
Ketan Priyadarshi Mahathi Gopalakrishnan ◽  
Tamilarasu Kadhiravan Apurba Sankar Sastry
Keyword(s):  
Bone Marrow ◽  
Brucella Melitensis ◽  
Public Health Problem ◽  
Febrile Illness ◽  
Human Brucellosis ◽  
Automated Identification ◽  
Serological Tests ◽  
Test Culture ◽  
Significant Public Health Problem ◽  
Significant Public Health

Brucellosis is a bacterial zoonosis usually associated with exposure to infected animals or their products. Although a significant public health problem in India, exact prevalence and distribution are unknown owing to the imprecision of diagnosis and inadequacy of reporting and surveillance. Although the febrile illness is common, its manifestations are highly variable. Bone marrow suppression and consequent pancytopenia have been rarely reported. We present a case of 50 years old female diagnosed with human brucellosis associated with pancytopenia and non-specific clinical presentation, that was diagnosed incidentally on blood and bone-marrow culture. This was confirmed by serological tests like the standard agglutination test. Culture isolation using automated blood culture (e.g. BacT/ALERT), followed by identification using automated identification systems (e.g. MALDI-TOF and VITEK-2) help to reach accurate and timely diagnosis aiding in the management of the patient.

scholarly journals Investigation on Brucella infection in farm animals in Saham, Sultanate of Oman with reference to human brucellosis outbreak

2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Yasmin ElTahir ◽  
Anfal Al-Farsi ◽  
Waleed Al-Marzooqi ◽  
Alghalya Al-Toobi ◽  
Osman M. Gaafar ◽  
...  
Keyword(s):  
Brucella Melitensis ◽  
Phase 1 ◽  
Time Frame ◽  
Farm Animals ◽  
Human Brucellosis ◽  
Biochemical Tests ◽  
Serological Tests ◽  
Molecular Tests ◽  
The Status ◽  
Bronchial Lymph Node

Abstract Background The objective of this study was to investigate Brucella infection in farm animals in Saham, Oman, with reference to a survey carried out by the Ministry of Agriculture & Fisheries (MAF) for Brucellosis during the period of May to July 2016 in Saham, following an outbreak of human brucellosis. We wanted to apply different serological, bacteriological and molecular tests in a time frame (phase 1, 2 & 3) with reference to the pivotal time of a human brucellosis outbreak to ascertain the status of the disease in Saham area where the MAF survey was conducted. Blood samples were collected from farm animals and sera were screened in parallel for Brucella antibodies using different serological tests. Results Using the RBT test, phase 1 sera showed seropositivity in sheep at 2.6%, (95% CI: 0.5–13.5%), in camel (5.9%, 1.1–27.0%), but not in sera from goats and cattle (0%). Using I-ELISA, seropositivity in goat was 3.1% (0.6–15.8%), with no positive sheep and cattle. Using c-ELISA for camel we found a seropositivity of 5.9% (1.1–27.0%). Furthermore, CFT seropositivity in goats was 21.9% (CI: 11.3–38.9), cattle and sheep sera were negative and camel was 5.9% (1.1–27.0%). In phase 2, the seropositivity in goats was 1.9% (1.4–2.6%), sheep 4.5% (3.5–5.8%), cattle 1.1%, (0.5–2.3%) and camels 18.2% (5.1–47.7%), Phase 3 sera were collected 6 months after the human brucellosis outbreak. With RBT, the seropositivity in goats was 3% (1.0–8.5%), sheep 2% (0.6–7.1%) cattle 1% (0.2–5.5%). With I-ELISA, goats & camels were negative, sheep were 3% (1.0–8.5%) and cattle 1% (0.2–5.5%). Moreover, B. melitensis was isolated from a bronchial lymph node of the RBT and I-ELISA seropositive cow and confirmed by Multiplex PCR and biochemical tests. Conclusion Using a retrospective study analysis of animal sera and following up after a human brucellosis outbreak, the present study showed a slight decrease in seropositivity of infected animals after the MAF implemented test and slaughter policy. The most interesting finding in this study was the isolation, identification and molecular characterization of Brucella melitensis in a cow (spillover), which is not a preferential host for Brucella melitensis.

scholarly journals Diagnosis of COVID-19 by Serology in Admitted Patients with Negative RT-PCR Assay

2021 ◽  
Author(s):  
Mitra Rezaei ◽  
Parvaneh Baghaei ◽  
Makan Sadr ◽  
Afshin Moniri ◽  
Abdolreza Babamahmoodi ◽  
...  
Keyword(s):  
Diagnostic Yield ◽  
Serological Test ◽  
False Negative ◽  
Diagnostic Methods ◽  
Rt Pcr ◽  
Pcr Assay ◽  
Serological Tests ◽  
Negative Results ◽  
False Negative Results ◽  
Polymerase Chain

Considering the increasing prevalence and burden of coronavirus disease 2019 (COVID-19) disease and false-negative results in routine reverse transcription-polymerase chain reaction (RT-PCR) tests, additional diagnostic methods are needed to diagnose active cases of this disease. This prospective study was conducted on patients, in whom clinical and radiological symptoms/signs were in favor of COVID-19 while their first PCR test was negative. Later on, a second RT-PCR was performed and serological evaluation was carried out and results were compared with each other. Out of 707 patients who had been referred to the hospital and were clinically and radiologically suspicious of disease, 137 patients with negative RT-PCR tests entered the study. RT-PCR assay became positive for the second time in 45 (32.8%). Anti-COVID-19 IgM and IgG antibodies were positive in 83 (60.6%) and 86 (62.8%) patients, respectively. Finally, it was determined that serological test was diagnostic in 73% of patients and the diagnostic yield of serology was significantly higher after the first week of illness (54.8% in the first week and 88% after that). Taking advantage of both serological tests and RT-PCR helps in diagnosing 83.9% of cases. Based on the present study, the serology may be useful as a complementary test and in parallel to RT-PCR assay for diagnosis of COVID-19 among admitted symptomatic cases.

scholarly journals CLINICAL AND LABORATORY DIAGNOSES OF NEWCASTLE AND INFECTIOUS BURSAL DISEASES OF CHICKENS

2012 ◽  
Vol 8 (2) ◽  
pp. 131-140 ◽  
Author(s):  
AKM Rakibul Hasan ◽  
MH Ali ◽  
MP Siddique ◽  
MM Rahman ◽  
MA Islam
Keyword(s):  
Newcastle Disease ◽  
Serological Test ◽  
Clinical Signs ◽  
Virus Detection ◽  
Clinical History ◽  
Rapid Identification ◽  
Rt Pcr ◽  
Pcr Assay ◽  
Serological Tests ◽  
Field Samples

A comparative study was conducted to compare the disease diagnostic parameters (clinical signs & postmortem findings, organism isolation, serological test and molecular method) used to diagnose the Newcastle disease (ND) and infectious bursal disease (IBD) during the period from March 2009 to February 2010 in the laboratory of the Department of Microbiology and Hygiene, Bangladesh Agricultural University (BAU), Mymensingh. A total of 187 sick and dead chickens (63 broilers and 124 layers) of different ages (1 week to >15 weeks) were collected from 12 selective poultry farms (4 broilers and 8 layers) of Mymensingh and Gazipur districts. Clinically, 7 (14.89%) of 63 affected broiler and 27 (30.68%) of 124 affected layer chickens were diagnosed as Newcastle disease (ND) whereas, 11 (23.4%) of 63 affected broiler and 6 (4.82%) of the 124 affected layer birds were diagnosed as IBD on the basis of clinical history, clinical signs and postmortem findings. Virus isolation from field samples was performed by inoculating each suspected sample into 10-day-old chicken embryos. Out of 34 ND suspected field samples, 26 (5 broilers and 21 layers) were positive for NDV isolation and 11 (8 broilers and 3 layers) of 17 IBD suspected field samples, were positive for IBDV isolation. For confirmatory diagnosis, virus detection was confirmed by serological tests (HI and AGID) and RT-PCR assay. Out of 34 clinically diagnosed ND field samples, 20 (5 broiler & 15 layer) were positive by RT-PCR assay and 15 (10 broiler & 5 layer) of 17 IBD suspected field samples, were positive by both AGIDT and RT-PCR assay. Of the 26 HA positive NDV suspected AF, 19 (4 broilers and 15 layers) were positive by both HI & RT-PCR assay whereas, 10 (7 broilers and 3 layers) of 11 IBDV isolation positive tissue suspension were positive by both AGIDT & RT-PCR assay in the laboratory. Therefore, it may be concluded that serological (HI & AGIDT) and molecular (RT-PCR) techniques which allow rapid identification of most of samples are the reliable, sensitive, specific and more accurate methods to detect the viruses for the confirmatory diagnosis of diseases.DOI = http://dx.doi.org/10.3329/bjvm.v8i2.11196 Bangl. J. Vet. Med. (2010). 8 (2) : 131-140 

A Hemi-nested, Allele Specific, Whole Blood PCR Assay for the Detection of the Factor V Leiden Mutation

1997 ◽  
Vol 77 (06) ◽  
pp. 1154-1155 ◽  
Author(s):  
Gary D Sinclair ◽  
Sandra Low ◽  
Man-Chiu Poon
Keyword(s):  
Whole Blood ◽  
Protein C ◽  
Activated Protein C ◽  
Factor V Leiden ◽  
Restriction Enzyme Digestion ◽  
Factor V ◽  
Pcr Assay ◽  
Specific Primers ◽  
Factor V Leiden Mutation ◽  
Allele Specific

SummaryWe describe a novel hemi-nested, allele specific whole blood PCR assay for detection of the factor V Leiden mutation associated with the plasma defect, activated protein C resistance. This assay utilizes 5 μl of whole blood without prior DNA extraction. The hemi-nested design, employing an outer primer pair in combination with nested, allele specific primers obviates the need for restriction enzyme digestion. PCR reactions are analysed directly on agarose or polyacrylamide minigels. The assay confirmed the genotypes of 50 individuals previously categorized by PCR and Mnll digestion, and has been subsequently utilized in the genotyping of 445 individuals referred for thrombosis studies.

AFLP-derived, Codominant Markers for Locus-specific Applications

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 514e-514
Author(s):  
James M. Bradeen ◽  
Philipp W. Simon
Keyword(s):  
Linkage Mapping ◽  
Large Scale ◽  
Pcr Primers ◽  
Inverse Pcr ◽  
Sequence Information ◽  
Pcr Assay ◽  
Specific Primers ◽  
Simultaneous Evaluation ◽  
Feral Populations ◽  
Diversity Assessment

The amplified fragment length polymorphism (AFLP) is a powerful marker, allowing rapid and simultaneous evaluation of multiple potentially polymorphic sites. Although well-adapted to linkage mapping and diversity assessment, AFLPs are primarily dominant in nature. Dominance, relatively high cost, and technological difficulty limit use of AFLPs for marker-aided selection and other locus-specific applications. In carrot the Y2 locus conditions carotene accumulation in the root xylem. We identified AFLP fragments linked to the dominant Y2 allele and pursued conversion of those fragments to codominant, PCR-based forms useful for locus-specific applications. The short length of AFLPs (≈60 to 500 bp) precludes development of longer, more specific primers as in SCAR development. Instead, using sequence information from cloned AFLP fragments for primer design, regions outside of the original fragment were amplified by inverse PCR or ligation-mediated PCR, cloned, and sequenced. Differences in sequences associated with Y2 vs. y2 allowed development of simple PCR assays differentiating those alleles. PCR primers flanking an insertion associated with the recessive allele amplified differently sized products for the two Y2 alleles in one assay. This assay is rapid, technologically simple (requiring no radioactivity and little advanced training or equipment), reliable, inexpensive, and codominant. Our PCR assay has a variety of large scale, locus-specific applications including genotyping diverse carrot cultivars and wild and feral populations. Efforts are underway to improve upon conversion technology and to more extensively test the techniques we have developed.

scholarly journals Analytical Validation and Clinical Application of Rapid Serological Tests for SARS-CoV-2 Suitable for Large-Scale Screening

Diagnostics ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 869
Author(s):  
Amedeo De Nicolò ◽  
Valeria Avataneo ◽  
Jessica Cusato ◽  
Alice Palermiti ◽  
Jacopo Mula ◽  
...  
Keyword(s):  
Early Diagnosis ◽  
Real Time Pcr ◽  
Large Scale ◽  
High Sensitivity ◽  
Analytical Validation ◽  
Pcr Assay ◽  
Serological Tests ◽  
Flow Test ◽  
Lateral Flow Test ◽  
Large Scale Screening

Recently, large-scale screening for COVID-19 has presented a major challenge, limiting timely countermeasures. Therefore, the application of suitable rapid serological tests could provide useful information, however, little evidence regarding their robustness is currently available. In this work, we evaluated and compared the analytical performance of a rapid lateral-flow test (LFA) and a fast semiquantitative fluorescent immunoassay (FIA) for anti-nucleocapsid (anti-NC) antibodies, with the reverse transcriptase real-time PCR assay as the reference. In 222 patients, LFA showed poor sensitivity (55.9%) within two weeks from PCR, while later testing was more reliable (sensitivity of 85.7% and specificity of 93.1%). Moreover, in a subset of 100 patients, FIA showed high sensitivity (89.1%) and specificity (94.1%) after two weeks from PCR. The coupled application for the screening of 183 patients showed satisfactory concordance (K = 0.858). In conclusion, rapid serological tests were largely not useful for early diagnosis, but they showed good performance in later stages of infection. These could be useful for back-tracing and/or to identify potentially immune subjects.

scholarly journals Molecular characteristics of Brucella melitensis isolates from humans in Qinghai Province, China

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Zhi-Jun Zhao ◽  
Ji-Quan Li ◽  
Li Ma ◽  
Hong-Mei Xue ◽  
Xu-Xin Yang ◽  
...  
Keyword(s):  
Tandem Repeats ◽  
Brucella Melitensis ◽  
Draft Genome ◽  
Geographic Origin ◽  
Variable Number ◽  
Human Brucellosis ◽  
Molecular Characteristics ◽  
Whole Genome ◽  
Qinghai Province ◽  
Variable Number Tandem Repeats

Abstract Background The prevalence of human brucellosis in Qinghai Province of China has been increasing rapidly, with confirmed cases distributed across 31 counties. However, the epidemiology of brucellosis transmission has not been fully elucidated. To characterize the infecting strains isolated from humans, multiple-locus variable-number tandem repeats analysis (MLVA) and whole-genome single-nucleotide polymorphism (SNP)-based approaches were employed. Methods Strains were isolated from two males blood cultures that were confirmed Brucella melitensis positive following biotyping and MLVA. Genomic DNA was extracted from these two strains, and whole-genome sequencing was performed. Next, SNP-based phylogenetic analysis was performed to compare the two strains to 94 B. melitensis strains (complete genome and draft genome) retrieved from online databases. Results The two Brucella isolates were identified as B. melitensis biovar 3 (QH2019001 and QH2019005) following conventional biotyping and were found to have differences in their variable number tandem repeats (VNTRs) using MLVA-16. Phylogenetic examination assigned the 96 strains to five genotype groups, with QH2019001 and QH2019005 assigned to the same group, but different subgroups. Moreover, the QH2019005 strain was assigned to a new subgenotype, IIj, within genotype II. These findings were then combined to determine the geographic origin of the two Brucella strains. Conclusions Utilizing a whole-genome SNP-based approach enabled differences between the two B. melitensis strains to be more clearly resolved, and facilitated the elucidation of their different evolutionary histories. This approach also revealed that QH2019005 is a member of a new subgenotype (IIj) with an ancient origin in the eastern Mediterranean Sea.

scholarly journals Seropositivity to canine tick-borne pathogens in a population of sick dogs in Italy

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Jairo Alfonso Mendoza-Roldan ◽  
Giovanni Benelli ◽  
Marcos Antonio Bezerra-Santos ◽  
Viet-Linh Nguyen ◽  
Giuseppe Conte ◽  
...  
Keyword(s):  
Borrelia Burgdorferi ◽  
Serological Test ◽  
Control Strategies ◽  
Central Italy ◽  
Rickettsia Conorii ◽  
High Seroprevalence ◽  
The South ◽  
Serum Samples ◽  
Serological Tests ◽  
Distribution Maps

Abstract Background Canine vector-borne diseases (CVBDs) associated to ticks are among the most important health issues affecting dogs. In Italy, Ehrlichia canis, Anaplasma spp., Rickettsia conorii and Borrelia burgdorferi (s.l.) have been studied in both healthy canine populations and those clinically ill with suspected CVBDs. However, little information is currently available on the overall prevalence and distribution of these pathogens in the country. The aim of this study was to assess the prevalence and distribution of tick-borne pathogens (TBPs) in clinically suspect dogs from three Italian macro areas during a 15-year period (2006–2020). Methods A large dataset (n = 21,992) of serological test results for selected TBPs in three macro areas in Italy was analysed using a Chi-square test to evaluate the associations between the categorical factors (i.e. macro area, region, year, sex and age) and a standard logistic regression model (significance set at P = 0.05). Serological data were presented as annual and cumulative prevalence, and distribution maps of cumulative positive cases for TBPs were generated. Results Of the tested serum samples, 86.9% originated from northern (43.9%) and central (43%) Italy. The majority of the tests was requested for the diagnosis of E. canis (47%; n = 10,334), followed by Rickettsia spp. (35.1%; n = 7725), B. burgdorferi (s.l.) (11.6%; n = 2560) and Anaplasma spp. (6.2%; n = 1373). The highest serological exposure was recorded for B. burgdorferi (s.l.) (83.5%), followed by Rickettsia spp. (64.9%), Anaplasma spp. (39.8%) and E. canis (28.7%). The highest number of cumulative cases of Borrelia burgdorferi (s.l.) was recorded in samples from Tuscany, central Italy. Rickettsia spp. was more prevalent in the south and on the islands, particularly in dogs on Sicily older than 6 years, whereas Anaplasma spp. was more prevalent in the north and E. canis more prevalent in the south and on the islands. Conclusions The results of this study highlight the high seroprevalence and wide distribution of the four TBPs in dogs with clinically suspected CVBDs from the studied regions of Italy. The very high seroprevalence of B. burgdorferi (s.l.) exemplifies a limitation of this study, given the use of clinically suspect dogs and the possibility of cross-reactions when using serological tests. The present research provides updated and illustrative information on the seroprevalence and distribution of four key TBPs, and advocates for integrative control strategies for their prevention. Grapic abstract

scholarly journals Laboratory Animal Models for Brucellosis Research

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Teane M. A. Silva ◽  
Erica A. Costa ◽  
Tatiane A. Paixão ◽  
Renée M. Tsolis ◽  
Renato L. Santos
Keyword(s):  
Animal Models ◽  
Chronic Infection ◽  
Laboratory Animal ◽  
Animal Species ◽  
Human Brucellosis ◽  
Intracellular Pathogen ◽  
Gram Negative ◽  
Culture Cells ◽  
Pathogenic Factors ◽  
The World

Brucellosis is a chronic infectious disease caused byBrucellaspp., a Gram-negative facultative intracellular pathogen that affects humans and animals, leading to significant impact on public health and animal industry. Human brucellosis is considered the most prevalent bacterial zoonosis in the world and is characterized by fever, weight loss, depression, hepato/splenomegaly, osteoarticular, and genital infections. Relevant aspects ofBrucellapathogenesis have been intensively investigated in culture cells and animal models. The mouse is the animal model more commonly used to study chronic infection caused byBrucella. This model is most frequently used to investigate specific pathogenic factors ofBrucellaspp., to characterize the host immune response, and to evaluate therapeutics and vaccines. Other animal species have been used as models for brucellosis including rats, guinea pigs, and monkeys. This paper discusses the murine and other laboratory animal models for human and animal brucellosis.

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