Serological Procedures Research Articles

Not bitten by Ixodes ticks or bitten without symptoms, why still to worry?

The purpose of the current study was to analyse the risks of Lyme borreliosis (LB) among 1,070 forestry workers, the influence of responsible behaviour (use of repellents, skin self-inspection) on Borrelia screening result status, and the occurrence of immediate and mid-term symptoms after tick bites and LB positive serological screening test. The questionnaire was conducted as well as blood tests for LB disease by one-stage serological screening procedure using ELISA for specific B. burgdorferi IgM and IgG antibodies (EuroImmun AG company, Germany). While 39.6% of foresters were LB positive among bitten foresters, as many as 27.0% were LB positive among those, who did not recall any tick attacks at all. Individuals with known history of tick bites had significantly higher odds (1.770×) of being LB positive (p < 0.05), while the use of repellents or skin self-inspection after visiting woods had no influence on LB results. The odds of skin discolouration after tick bites was significantly lower (0.682×) in case of LB positive test compared to LB negative test (p < 0.05), which can be explained by the fact that foresters could be unaware about erythema migrans appearance and timing, considering tick bite and developed later rash as completely separate events. Moreover, 69.1% of the bitten foresters with LB positive result developed no secondary symptoms (excluding those related to the skin), and the most frequent clinical symptoms were arthralgia (24.9%), followed by myalgia (7.6%), headache (5.7%), and damage to facial nerve (2.7%), which are non-specific and can be present in other illnesses. Therefore, the recommendations proposed would be the regular laboratory testing for LB of sensitive and at-risk population, who visits endemic woody areas, irrespective of all other factors involved.

First investigation of RH gene polymorphism in patients with sickle cell disease and associated blood donors in Cameroon, Central Africa.

Although genetic polymorphism of the RH blood group system is well known in sub-Saharan Africa, national/regional specificities still remain to be described precisely. For the first time in Cameroon, Central Africa, and in order to better characterize the molecular basis driving RH phenotype variability, as well as to identify the main antigens that may be potentially responsible for alloimmunization, we sought 1) to study the RH genes in a cohort of 109 patients with sickle cell disease; 2) to study the same genes in the corresponding donors whose red blood cells (RBCs) were transfused to the patients (108 donors in 98 patients); 3) to predict RH phenotype on the basis of the molecular data and compare the results with serologic testing; and 4) to identify retrospectively patients at risk for alloimmunization. In order to generate an exhaustive dataset, the RH genes of all patient and donor samples were systematically investigated 1) by quantitative multiplex PCR of short fluorescent fragments (QMPSF) for characterization of RHD gene zygosity and potential structural variants (SVs), and 2) by Sanger sequencing for identification of single nucleotide variants (SNVs). Subsequent to molecular analysis, the genotypes and RH phenotype were deduced and predicted, respectively, from reference databases. In a total of 217 Cameroonian individuals, as many as 24 and up to 22 variant alleles were identified in the RHD and RHCE genes, respectively, in addition to the reference alleles. Interestingly, 65 patients with SCD (66.3%) were assumed to be exposed to one or more undesirable RH antigen(s) with varying degrees of clinical relevance. Beyond the comprehensive report of the nature and distribution of RH variant alleles in a subset of Cameroonian patients treated by transfusion therapy, this work highlights the need for an extensive review of current practice, including routine serologic typing procedures, preferably in the near future.

Myasthenia-like paraneoplastic syndrome with multiple cranial nerve tumor infiltration: A case report and literature review.

Approximately 0.001% of patients with cancer have paraneoplastic nerve system syndrome, which can affect the central nervous system, neuromuscular junction, or peripheral nervous system. Although myasthenia gravis (MG) may exist as a thymic paraneoplastic syndrome (PNPS), its association with primary lung cancer remains unknown. A 55-year-old female presented with slurred speech, weakness in chewing, sporadic difficulty in swallowing, and weakness in both lower limbs for half a year. Based on cerebrospinal fluid and electromyography findings, we present the case of a female patient diagnosed with overlapping multicranial nerve tumor infiltration and MG-like neurological PNPS secondary to lung adenocarcinoma. The patient received intrathecal injections of pemetrexed and neurotrophic (vitamin B) therapy before ceasing chemoradiotherapy and chose cabozantinib on her own. Weakness of the proximal limbs, choking cough, and chewing problems did not improve significantly. Although it is unclear why MG coexists with lung cancer, it is probable that MG is a paraneoplastic condition. Cerebrospinal fluid testing should be carried out along with electrophysiological, serological, and pharmacological procedures pertinent to the diagnosis of MG to thoroughly examine if people simultaneously experience MG-like PNPS and tumor growth. Starting immunotherapy and anticancer medication at the same time that tumor development and MG-like syndrome are discovered is crucial.

An Epidemiological Study of Brucellosis in Different Animal Species from the Al-Qassim Region, Saudi Arabia.

Brucellosis is a zoonotic bacterial illness that affects humans and a variety of domestic animals, especially ruminants. It is mostly transmitted through the consumption of contaminated drinks, foods, undercooked meat, or unpasteurized milk or contact with infected animals. Therefore, the present study aimed to investigate the seroprevalence of brucellosis in camels, sheep, and goat herds in the Qassim region, Saudi Arabia, using commonly used diagnostic serological procedures such as the Rose Bengal test (RBT), complement fixation test (CFT), and enzyme-linked immunosorbent assay (ELISA). The seroprevalence of brucellosis in camels, sheep, and goats was determined in the selected areas using a cross-sectional study design and a total of 690 farm animals of both sexes of different ages from the three animal species (274 camels, 227 sheep, and 189 goats). According to RBT results, 65 sera were positive for brucellosis, including 15 (5.47%) for camels, 32 (14.09%) for sheep, and 18 (9.50%) for goats. CFT and c-ELISA were performed as confirmatory tests on positive samples resulting from RBT. With c-ELISA, 60 serum samples were confirmed positive, in 14 (5.10%), 30 (13.21%), and 16 (8.46%) camels, sheep, and goats, respectively. There were 59 serum samples confirmed as positive for CFT, including 14 (5.11%), 29 (12.77%), and 16 (8.46%) for camels, sheep, and goats, respectively. Overall, the highest seroprevalence of brucellosis was found in sheep while the least was found in camels from the three tests (RBT, c-ELISA, and CFT). The highest seroprevalence of brucellosis was found in sheep while the least seroprevalence was found in camels. There was also a higher seroprevalence of brucellosis among female animals than males as well as among old animals than young animals. The study, thus, demonstrates brucellosis seroprevalence among farm animals (camels, sheep, and goats) and the significance of intervention measures against brucellosis incidence in both humans and animals through the creation of public awareness and other relevant policy measures such as livestock vaccination, effective hygiene management, and adequate quarantine or serological analysis for newly introduced animals.

Horizontal transfer of the rfb cluster in Leptospira is a genetic determinant of serovar identity.

Leptospira bacteria comprise numerous species, several of which cause serious disease to a broad range of hosts including humans. These spirochetes exhibit large intraspecific variation, resulting in complex tabulations of serogroups/serovars that crisscross the species classification. Serovar identity, linked to biological/clinical phenotypes, depends on the structure of surface-exposed LPS. Many LPS biosynthesis-encoding genes reside within the chromosomic rfb gene cluster. However, the genetic basis of intraspecies variability is not fully understood, constraining diagnostics/typing methods to cumbersome serologic procedures. We now show that the gene content of the rfb cluster strongly correlates with Leptospira serovar designation. Whole-genome sequencing of pathogenic L. noguchii, including strains of different serogroups, reveals that the rfb cluster undergoes extensive horizontal gene transfer. The rfb clusters from several Leptospira species disclose a univocal correspondence between gene composition and serovar identity. This work paves the way to genetic typing of Leptospira serovars, and to pinpointing specific genes within the distinct rfb clusters, encoding host-specific virulence traits. Further research shall unveil the molecular mechanism of rfb transfer among Leptospira strains and species.

A Study to Evaluate the Utility and Appropriateness of Diagnostic Workup for Leukocytosis in the Hematology Clinic

Background: Leukocytosis is a common abnormality in the complete blood count (CBC) that is often first noted by general practitioners. In addition to many benign causes of leukocytosis, malignant causes such as CML, myeloproliferative neoplasms (MPNs), and MDS/MPN overlap syndromes, must be evaluated for select patients by a hematology specialist. While some recommendations for evaluation and diagnostic workup for leukocytosis exist, the real-world appropriateness and utility of further serologic tests or diagnostic procedures, including bone marrow biopsy, remain largely unknown. The aim of this study is to determine hematological parameters in patients referred for evaluation of leukocytosis that are associated with MDS/MPN diagnoses and are therefore useful to the hematologist in selecting appropriate patients for further diagnostic testing. Methods: A retrospective chart review was conducted of 803 adult patients referred to the hematology clinic at a single institution between 2016-2021. 487 patients were included based on the inclusion criteria that they were referred for evaluation of leukocytosis and did not have a prior established hematologic diagnosis. Demographic and laboratory data were collected including CBCs, anemia workup, leukocytosis workup, JAK2 V617F mutation and BCR-ABL mutation results, and bone marrow biopsy results. Clinician notes were reviewed from the medical record to verify appropriate patient selection and data points. Statistical analyses were performed using Chi-Square/Fisher exact tests to evaluate for hematological parameters that are associated with the identification of MDS/MPNs as well as other hematologic malignancies, and a multivariable logistic regression model was used to analyze the association between hematological parameters and diagnosis of MDS/MPN. Results: 487 patients were included in analysis: 70% female, 44.6% white, 30% black or African American, and 25.5% Hispanic or Latino. After evaluation by a hematologist, 14.6% of patients were diagnosed with a hematologic malignancy, and 8% were diagnosed with MDS/MPN. Higher WBC, particularly greater than 15 x 109/L, was associated with diagnosis of MDS/MPN, any hematologic malignancy, and testing positive for BCR/ABL or JAK2 V617F (p <0.0001). Patients with an absolute neutrophil count (ANC) > ULN (7.8), absolute eosinophil count (AEC) > ULN (0.6), absolute basophil count (ABC) > ULN (0.3), platelet count >600, ferritin >50, and vitamin B12 > ULN (920) were more likely to be diagnosed with MDS or MPN (p <0.0001, <0.0001, <0.0001, <0.0001, 0.02, and 0.0006 respectively). These laboratory findings were also significantly associated with diagnosis of any hematologic malignancy, and many were associated with testing positive for BCR/ABL or JAK2 V617F mutations (ANC, AEC, ABC, and platelet count). Multivariable analysis results shows that ABC >= 0.3 (OR=27.7, 95% CI=3 - 255.3), platelet count >= 600 (OR=16.9, 95% CI=1.9 - 146.4), and vitamin B12 > 920 (OR=5.8, 95% CI=1.2 - 28.4) significantly increase the risk of being diagnosed with MDS/MPN. Conclusions: This retrospective study identified hematological parameters in patients referred for evaluation of leukocytosis including elevated ANC, AEC, ABC, and platelet count that were significantly associated with testing positive for BCR/ABL mutation or JAK2 V617F mutation. These parameters, in addition to vitamin B12 and ferritin, were associated with positive identification of hematologic neoplasms and specifically MDS/MPNs. These parameters may guide hematologists in selecting appropriate patients for further serologic or procedural testing, such as JAK2 V617F and BCR/ABL mutation testing and bone marrow biopsy, in order to avoid unnecessary testing and decrease the financial cost of evaluation.

Comparing in vivo bioluminescence imaging and the Multi-Cruzi immunoassay platform to develop improved Chagas disease diagnostic procedures and biomarkers for monitoring parasitological cure.

BackgroundChagas disease is caused by the protozoan parasite Trypanosoma cruzi and is a serious public health problem throughout Latin America. With 6 million people infected, there is a major international effort to develop new drugs. In the chronic phase of the disease, the parasite burden is extremely low, infections are highly focal at a tissue/organ level, and bloodstream parasites are only intermittently detectable. As a result, clinical trials are constrained by difficulties associated with determining parasitological cure. Even highly sensitive PCR methodologies can be unreliable, with a tendency to produce “false-cure” readouts. Improved diagnostic techniques and biomarkers for cure are therefore an important medical need.Methodology/Principal findingsUsing an experimental mouse model, we have combined a multiplex assay system and highly sensitive bioluminescence imaging to evaluate serological procedures for diagnosis of T. cruzi infections and confirmation of parasitological cure. We identified a set of three antigens that in the context of the multiplex serology system, provide a rapid, reactive and highly accurate read-out of both acute and chronic T. cruzi infection. In addition, we describe specific antibody responses where down-regulation can be correlated with benznidazole-mediated parasite reduction and others where upregulation is associated with persistent infection. One specific antibody (IBAG39) highly correlated with the bioluminescence flux and represents a promising therapy monitoring biomarker in mice.Conclusions/SignificanceRobust, high-throughput methodologies for monitoring the efficacy of anti-T. cruzi drug treatment are urgently required. Using our experimental systems, we have identified markers of infection or parasite reduction that merit assessing in a clinical setting for the longitudinal monitoring of drug-treated patients.

Internal Transcribed Spacer (ITS) Region as Molecular Marker for Parasite Identification in Aquaculture: A Review

Molecular technologies may be quicker and more accurate than the culture, serology, and histology procedures that have historically been employed to identify fish parasites. By using molecular diagnostic methods, parasites can be found in asymptomatic fish, allowing disease outbreaks to be stopped. This review discusses the use of Internal Transcribed Spacer (ITS) markers to detect parasite in aquaculture and their potential applications are discussed. It was found that it is a more reliable marker and species identification in combination with other DNA markers. ITS region are highly polymorphic non - coding region with sufficient taxonomic units. Thus, sequences can be separated at the species level. though ribosomal ITS as a universal barcode marker for parasite identification is still hampered by few limitations, the ITS will remain as the key choice for parasite identification. It remains the most important option for parasite identification. Many studies have been carried out using ITS markers for parasites identification such as cestode, nematodes, Pseudoterranova spp., Anisakis type I, Diplostomum, Gyrodactylids Hysterothylacium sp, Glochidia larvae. This identification of parasites are taken from the species Rainbow trout (Oncorhynchus mykiss), Argentinesea bass, (Acanthistius patachonicus), and other samples from various places.

Molecular genetic analysis reveals a novel B variant allele at the ABO locus

BackgroundWhen discrepancies in ABO blood typing emerge, ABO subgroups should be considered. Serological procedures such as the adsorption-elution test, the salivary ABH inhibition test, and the antiA1 (lectin) saline technique might be employed. These serological approaches, however in rare blood types are difficult to understand. As a result, a dependable and cost-effective approach for determining ABO subgroups is of special relevance. Methodologyfor this purpose, DNA sequencing is most reliable solution for accurate results. Exon 1 to 7 5′ 3’ UTR and intron 6 of ABO gene of a Chinese individual was sequenced because the laboratory was unable to determine the blood group by traditional method. ResultsThe analysis of the blood showed weak B antigens on their surface. Gene sequencing results revealed a novel B allele, that has one novel identified nucleotide difference from T to C at nucleotide 425. ConclusionThe results reported novel B allele which cannot be confirmed by conventional serological methods. Owing to the peculiarity of ABO blood types of inheritance, findings on the incidence and molecular causes of rare blood groups in the Chinese population have substantial therapeutic implications and are worthy of additional investigation in the future.

A Review on Newer Detection Technologies for the Diagnosis of COVID-19 Infection

COVID-19 is a sickness brought about by coronavirus responsible for causing simple to extreme complications in people. COVID-19 first case was seen in Wuhan, Hubei Province, China, on December, 2019. The World Health Organization (WHO) to pronounce it as a worldwide pandemic on March 11, 2020, as the pandemic has spread quickly all through the world. Regardless of extensive endeavors made to contain the infection, the infection has proceeded with its pervasiveness in numerous nations with changing levels of clinical signs. Henceforth, in this report, we discuss the various strategies, for example, serological and nucleic acid-based procedures which are accessible for the determination and successful counteraction of coronavirus. With expanding the rate of coronavirus cases, the precise and early identification of the COVID-19 is the need of great importance for viable avoidance with treatment and just as to check its spread. Reverse transcriptase-real time polymerase chain reaction (PCR) measures are viewed as the highest quality level for the early identification of infection. This diagnostic technique is being utilized worldwide with recommendations from WHO and Center for Disease Control and Prevention. Reverse transcriptase real-time quantitative PCR (RT-qPCR) is being done compulsory before any medical procedures and major surgeries for early detection, prevention, and management in due time course. Rapid antigen test is also a screening test used widely in hospitals for screening of COVID-19 and before the admission in hospitals. Other nucleic acid amplification test widely done for the detection of COVID-19 are RT-qPCR, next-generation sequencing, clustered regularly interspaced short pallindromic repeats, reverse transcription -loop-mediated isothermal amplification, droplet digital PCR. Some immunological tests are lateral flow, ELISA.

ANALYSIS OF WIDAL SLIDE TEST ON TIFOID FEVER PATIENTS IN SUNDARI MEDAN GENERAL HOSPITAL

Typhoid fever is an acute systemic disease caused by Salmonella typhi and Salmonella paratyphi A, B and C are characterized by prolonged fever, bacteremia without changes in the endothelial system. Salmonella is a genus of gram-negative enterobacteria bacteria in the form of rods, flagellated, without spores, capsules, and anaerobes that cause typhoid and paratyphoid. Salmonella is the leading cause of foodborne illness. In general, Salmonella causes diseases of the digestive organs. Salmonella antigen structure consists of flagellar antigen (H antigen), somatic antigen (O antigen). Widal test is a serological test procedure to detect Salmonella typhi bacteria infection that causes typhoid fever. This test will show the Salmonella antibody reaction to O- somatic, H-flagellar and Vi (bacterial hoops) antigens in the blood. Culture is the gold standard in examining typhoid fever cases to date because in culture we can determine the morphology of Salmonella. This type of research is a descriptive study that aims to analyze the results of the Widal Slide Test with the agglutination method in the Sundari General Hospital Laboratory, Medan. Of the 15 samples analyzed, the results of the Widal Slide Test were obtained for 33% of typhoid fever patients with agglutination and 67% of those without agglutination. The results were Salmonella typhi O = 4 samples, Salmonella typhi H = 1 sample, Salmonella paratyphi AO = 1 sample, Salmonella paratyphi BO = 2 samples, and Salmonella paratyphi CO = 3 samples. This type of research is a descriptive study that aims to analyze the results of the Widal Slide Test with the agglutination method in the Sundari General Hospital Laboratory, Medan. Of the 15 samples analyzed, the results of the Widal Slide Test were obtained for 33% of typhoid fever patients with agglutination and 67% of those without agglutination. The results were Salmonella typhi O = 4 samples, Salmonella typhi H = 1 sample, Salmonella paratyphi AO = 1 sample, Salmonella paratyphi BO = 2 samples, and Salmonella paratyphi CO = 3 samples. This type of research is a descriptive study that aims to analyze the results of the Widal Slide Test with the agglutination method in the Sundari General Hospital Laboratory, Medan. Of the 15 samples analyzed, the results of the Widal Slide Test were obtained for 33% of typhoid fever patients with agglutination and 67% of those without agglutination. The results were Salmonella typhi O = 4 samples, Salmonella typhi H = 1 sample, Salmonella paratyphi AO = 1 sample, Salmonella paratyphi BO = 2 samples, and Salmonella paratyphi CO = 3 samples.

The role of serological and molecular testing in the diagnostics and transfusion treatment of autoimmune haemolytic anaemia.

Autoimmune haemolytic anaemia (AIHA) is a rare autoimmune disease characterised by haemolysis associated with the presence of immunoglobulins and/or components of the complement system on red blood cells (RBCs). It is classified into warm or cold antibody-mediated AIHA according to the temperature at which autoantibodies bind optimally to RBCs. Clinicians should be familiar with the procedural tests used for a complete laboratory investigation of AIHA. Good collaboration between clinicians and laboratory specialists with correct sample handling and an exact diagnostic work-up is extremely important for the correct classification and proper therapeutic management of AIHA. Specialised serological test procedures are very complex. Problems with serological testing may be excluded with the molecular testing, which has now become a gold standard to predict a patient's phenotype in order to secure the right antigen-matched blood for AIHA patients. More recently, genotyping has been used instead of serological typing and complex adsorption tests. This paper offers a description of various tests for differentiating between types of AIHA. A diagnostic algorithm and the problems of laboratory investigation are also presented, and an application of molecular methods for the blood group typing in AIHA is elaborated.

Some Serological Analytic Approaches and Test Execution in Determination of Bovine Brucellosis: Overview

Bovine brucellosis is a highly contagious, zoonotic, and economically significant bacterial disease. The purpose of this paper was to review available scientific data on serological tests for the diagnosis of bovine brucellosis and compare test performance based on assay sensitivity (Se) and specificity (Sp) values. Abortion, placentitis, epididymitis, and orchitis are symptoms of the disease. The clinical picture of brucellosis is not pathognomonic, and the patient's clinical history, particularly the occurrence of abortion, is crucial for diagnosis. Although the causative agent is isolated and identified for a definitive diagnosis of bovine brucellosis, serological tests are usually preferred. The host defense mechanism against Brucella is functionally divided into innate or non-specific immunity and adaptive or specific immunity. The pathogenic brucella organism has evolved a slew of mechanisms for evading and/or modulating both innate and adaptive immune responses in its host. Serological assays are based on the fact that Brucella abortus and other smooth Brucella have a unique O-polysaccharide that induces a humoral response with the production of IgM first, followed by IgG1, and then IgG2/IgA. Screening serological tests (Milk ring test, Rose Bengal Test (RBT), and Buffered plate agglutination test (BPAT)) and confirmatory serological tests (complement fixation test (CFT), serum agglutination test (SAT), 2-mercaptoethanol test (2ME), indirect-enzyme-linked immunosorbent assay (iELISA), and, more recently, competitive-ELISA (cELISA) and Brucella fluorescent pol (FPA). CFT, RBT, and iELISA tests are currently used in EU legislation for intra-community cattle trade and show comparable Se and Sp. The new FPA test demonstrated Se and Sp levels comparable to standard tests and was proposed for inclusion as a standard test in EU legislation. Similarly, the OIE considers the four tests to be a mandatory requirement for international trade. Several methods, however, produce both false-positive and false-negative results. There is no single serological test that is 100% accurate and applicable in all epidemiological situations. In general, confirmatory serological procedures involve testing each serum with multiple tests, usually a screening test with high sensitivity followed by a confirmatory test with high specificity. As a result, the development of rapid, low-cost serological tests with high sensitivity and specificity for brucellosis detection is a major issue that requires further investigation. Keywords: Bovine Brucellosis; Brucella Abortus; Diagnosis; Sensitivity; Specificity; Serological Tests, Test Performance DOI: 10.7176/JNSR/13-12-03 Publication date: June 30 th 2022

Assessment of Liaison XL Murex Chagas diagnostic performance in blood screening for Chagas disease using a reference array of chimeric antigens.

BackgroundChagas disease (CD) serological screening at blood banks is usually performed by a single highly sensitive serological assay, with chemiluminescent immunoassays (CLIAs) being the method of choice. CLIAs employ recombinant, fusion peptides and/or chimeric antigens that selectively capture anti‐Trypanosoma cruzi antibodies. However, despite high sensitivity, the ability of these tests to identify CD‐positive cases should be evaluated against T. cruzi strains circulating in specific locales. Herein, we used a latent class analysis (LCA) approach employing an array of four chimeric antigens to assess the diagnostic performance of the Liaison XL Murex Chagas CLIA for the detection of anti‐T. cruzi IgG in serum samples.Study Design and MethodsThe study included a panel of 5014 serum samples collected from volunteer blood donors at the Hematology and Hemotherapy Foundation of the State of Bahia, submitted to anti‐T. cruzi antibody detection using Liaison Chagas CLIA and LCA as a reference test in the absence of a gold standard.ResultsLCA classified 4993 samples as negative, while positivity for T. cruzi antibodies was predicted in 21 samples. Compared with LCA, CLIA demonstrated sensitivity and specificity of 76.2% and 99.5%, respectively, providing an overall accuracy of 99.4%.DiscussionIn blood banks lacking a de facto highly sensitive screening immunoassay, the low sensitivity offered by Liaison Chagas CLIA renders it unsuitable for standalone use in serological screening procedures for CD. Moreover, blood banks are encouraged to carefully assess the ability of diagnostic methods to identify local T. cruzi strains in circulation.

Выявление и прогнозирование рисков распространения природно-очаговых инфекций на пострадавших от паводка территориях Иркутской области

In summer 2019 in western Irkutsk region abundant and long rainfall caused a catastrophic flood that became a federal emergency. It resulted in a threat that natural infection foci would be activated in that emergency zone; given that, the Irkutsk Anti-plague Institute, together with Rospotrebnadzor territorial offices and regional veterinary authorities, conducted an epizootologic-epidemiologic study on affected territories in order to detect and predict possible epidemiologic risks. Totally, the study covered 30 socially significant objects and natural biotopes in three mu-nicipal districts in the region. We tested blood serum of people (244 samples), farm and home ani-mals (253), and organs taken from caught small mammals aiming at determining natural foci infec-tions in them with bacteriologic, serologic, and PCR procedures; overall. 4,370 examinations were performed. Share of immune people amounted to 13.1% regarding tularemia; 17.5%, tick-borne en-cephalitis; yersiniosis, 10.8%; leptospirosis, 3.1%; tick-borne borreliosis, 7.1%. Antibodies to pathogenic leptospira were detected in 36.0–81.3% farm animals and it can indicate there is a latent epizootic process. In July 2019 there was low population of synanthropic rodents in socially significant objects on affected territories and small mammals population also decreased in natural foci with high contagion rate for tularemia agent (down to 17.9%). In September 2019 rats were detected to inhabit food-related objects and small mammals migrated actively in natural stations, contagion rate with tularemia agent going down among them whereas there was a growth in conta-gion rate with leptospira (up to 40.0%). We also revealed new natural tularemia and leptospirosis foci. Activity in natural infections foci didn’t exceed long-term average level just after the flood; still, there are persisting risks on affected territories in Irkutsk region that an epidemiologic situation might get worse there. The paper contains recommendations on further epizootologic-epidemiologic monitoring and organizing prevention activities such as control over sanitary situation at socially significant objects, local deratization, and sanitation in natural foci of animal leptospirosis.

Detecting and predicting risks relayed to spread of natural foci infections on flood-affected territories in Irkutsk region

In summer 2019 in western Irkutsk region abundant and long rainfall caused a catastrophic flood that became a federal emergency. It resulted in a threat that natural infection foci would be activated in that emergency zone; given that, the Irkutsk Anti-plague Institute, together with Rospotrebnadzor territorial offices and regional veterinary authorities, conducted an epizootologic-epidemiologic study on affected territories in order to detect and predict possible epidemiologic risks. Totally, the study covered 30 socially significant objects and natural biotopes in three mu-nicipal districts in the region. We tested blood serum of people (244 samples), farm and home ani-mals (253), and organs taken from caught small mammals aiming at determining natural foci infec-tions in them with bacteriologic, serologic, and PCR procedures; overall. 4,370 examinations were performed. Share of immune people amounted to 13.1% regarding tularemia; 17.5%, tick-borne en-cephalitis; yersiniosis, 10.8%; leptospirosis, 3.1%; tick-borne borreliosis, 7.1%. Antibodies to pathogenic leptospira were detected in 36.0–81.3% farm animals and it can indicate there is a latent epizootic process. In July 2019 there was low population of synanthropic rodents in socially significant objects on affected territories and small mammals population also decreased in natural foci with high contagion rate for tularemia agent (down to 17.9%). In September 2019 rats were detected to inhabit food-related objects and small mammals migrated actively in natural stations, contagion rate with tularemia agent going down among them whereas there was a growth in conta-gion rate with leptospira (up to 40.0%). We also revealed new natural tularemia and leptospirosis foci. Activity in natural infections foci didn’t exceed long-term average level just after the flood; still, there are persisting risks on affected territories in Irkutsk region that an epidemiologic situation might get worse there. The paper contains recommendations on further epizootologic-epidemiologic monitoring and organizing prevention activities such as control over sanitary situation at socially significant objects, local deratization, and sanitation in natural foci of animal leptospirosis.

Development of a serological procedure for sensitive and rapid detection of Thladiantha dubia mosaic virus

Thladiantha dubia mosaic virus (ThDMV) from the wild Manchurian tuber gourd (Thladiantha dubia Bunge, Cucurbitaceae), is a novel tentative specie of the genus Potyvirus within the family Potyviridae. It may pose a potential risk to both cultivated crops and plants in the natural ecosystem. In the present study, we developed an ELISA procedure for detection of ThDMV. Coat protein (CP) of ThDMV was successfully expressed in Escherichia coli, and used to immunize rabbit for antiserum after being purified by using Ni-NTA affinity column. Results of indirect ELISA showed that the optimum dilutions of the coating antigen and antiserum were 1:160 (1 μg per well), and 1:2000 respectively. Western blot indicated that antibodies in the antiserum could specifically recognize and bind CP of ThDMV. An ELISA method was developed with the antiserum to detect ThDMV in plant extracts. Samples collected from potato fields in Northeast China and Northwest China were analyzed by ELISA and RT-PCR and both gave consistent results. The ELISA assay developed here has potential to be used as a sensitive, reliable and cost-effective tool for ThDMV detection in epidemiological studies.

Salmonella serotype assignment by sequencing analysis of intergenic regions of ribosomal RNA operons

Salmonella laboratorial detection is usually carried out by bacteriological culture and serological methods. Salmonella isolates are then classified into more than 2,650 serotypes with different somatic (O) and flagellar (H) antigenic combinations. More recently, DNA analysis methods were developed and applied for the identification of Salmonella serotypes, including intergenic spacer regions (ISRs) that separates DNA-encoding ribosomal subunits (rRNA gene) in Salmonella genomes. The present study aimed to evaluate the nucleotide diversity of the ISRs in 2 rRNA operons (rrnB and rrnH) for the assignment of Salmonella serotypes. A total of 63 Salmonella isolates (bacterial cultures) from 21 serotypes were obtained in the period of 2014 to 2017. DNA was extracted, and PCRs were used to detect the genus Salmonella and 4 important serotypes: Enteritidis, Gallinarum, Heidelberg, and Typhimurium. ISRs of the operons rrnB and rrnH were amplified by PCR and then sequenced. All sequence results were submitted to BLASTn search and were aligned in comparison to 72 Salmonella reference nucleotide sequences. The results demonstrated that 60 (95.2%) samples returned a sequence of the same serotype (determined by the traditional serological procedure) after searching in BLASTn and/or in the alignment with the reference sequences for both operons (rrnB and rrnH). These PCR-sequencing procedures had a general agreement index of 0.792 based on the Kappa analysis, 98.7% sensitivity value, 100% specificity, and 98.4% accuracy. Three different phylogenetic trees were generated from the alignments with the sequences of rrnH, rrnB, and rrnH plus rrnB and isolates clustered in specific branches according to the serotypes.

Diagnostic Tools for the Identification of Babesia sp. in Persistently Infected Cattle.

Bovine babesiosis is a tick-borne disease of cattle caused by the protozoan parasites of the genus Babesia. Babesia bovis, Babesia bigemina and Babesia divergens are considered by International health authorities (OIE) as the principal species of Babesia that cause bovine babesiosis. Animals that recover from a babesial primo infection may remain as persistent carriers with no clinical signs of disease and can be the source of infection for ticks that are able to acquire Babesia parasites from infected cattle and to transmit Babesia parasites to susceptible cattle. Several procedures that have been developed for parasite detection and diagnosis of this infectious carrier state constitute the basis for this review: A brief description of the direct microscopic detection of Babesia-infected erytrocytes; PCR-based diagnostic assays, which are very sensitive particularly in detecting Babesia in carrier cattle; in-vitro culture methods, used to demonstrate presence of carrier infections of Babesia sp.; animal inoculation, particularly for B. divergens isolation are discussed. Alternatively, persistently infected animals can be tested for specific antibabesial antibodies by using indirect serological assays. Serological procedures are not necessarily consistent in identifying persistently infected animals and have the disadvantage of presenting with cross reactions between antibodies to Babesia sp.

Current Status and Future Prospect of Brucella Blood Culture in Iran: A Review of the Recent Findings

The prevalence of brucellosis has increased in recent years in some regions in Iran, particularly in the western, northeastern, and some central areas. Undoubtedly, the main causes of brucellosis are the lack of vaccination coverage in livestock and distribution of dairy products. In addition, attention must be paid to the diagnostic difficulties associated with slow growth specificity and use of inefficient methods, which lead to the delayed diagnosis of the disease. All the available diagnostic procedures are currently used for the diagnosis of brucellosis, including isolation on culture media, serological procedures, and molecular techniques. Among these methods, isolation on culture media has shown the minimum efficiency, especially in blood specimens, which are the most commonly requested specimens in disease diagnosis. The influential factors could be the use of unapproved commercial kits, applying outdated diagnostic procedures, and using unqualified specimens in hospitalized patients. The present study aimed to enhance the current status of the isolation method, especially in the endemic areas for brucellosis. Several parameters were assessed in this regard, including the role of laboratory conditions, sampling quality, type of culture media, and various isolation methods, in order to review the studies aiming to increase the efficiency of this method.