Indirect Fluorescent Antibody Technique Research Articles

Molecular characterization of Marek's Disease virus reveals reticuloendotheliosis virus-long terminal repeat integration in the genome of the field isolates in Egypt

The highly contagious, immunosuppressive, and cancer-causing Marek's disease virus (MDV) infects chickens. The financial costs of Marek's disease (MD) are significant for the chicken industry. In this study, a total of 180 samples from chicken farms suspected to be MDV-infected were collected. The chickens were sampled during the period between the months of October 2016 and February 2018 at Dakahlia and Damietta Governorates, Egypt. A total of 36 pooled samples were created. The prepared samples were inoculated into embryonated chicken eggs (ECEs). Indirect fluorescent antibody technique (IFAT) and ICP4 gene-based polymerase chain reaction (PCR) were used for MDV identification. For the genetic characterization of the identified virus, The ICP4 gene sequence was identified and compared with the sequences available from various regions of the world. Furthermore, the genomes of all detected MDVs were screened for the long terminal repeat (LTR) region of reticuloendotheliosis (REV) in their genomes. The results showed that 31 out of 36 pooled samples (86.1%) inoculated into ECEs displayed the characteristic pock lesions. By using IFAT and PCR to identify MDV in ECEs, positive results were found in 27 samples (75%). The Egyptian virus is thought to be genetically closely related to MDVs circulating in Ethiopia, China, and India. REV-LTR was amplified from 6 out of 27 field isolates genomes (22.2 %) while MDV vaccine strains were free from REV-LTR insertion. The integrated REV-LTRs depicted a close genetic relationship with those integrated in fowl poxvirus (FWPV) circulating in Egypt as well as those integrated in FWPVs and MDVs from China, USA, South Africa, and Australia. To the best of our knowledge, this investigation represents the first identification and characterization of REV-LTR insertions in Egyptian MDV field isolates. Given the findings above, additional research in the future seems crucial to determine how the REV-LTR insertions affect MDV pathogenesis, virulence, and insufficient vaccination protection.

Production and Characterization of Monoclonal Antibodies Against Structural Proteins of Hirame Novirhabdovirus

Hirame novirhabdovirus (HIRRV) is a significant viral pathogen of Japanese flounder (Paralichthys olivaceus). In this study, seven monoclonal antibodies (mAbs) against HIRRV (isolate CA-9703) were produced and characterized. Three mAbs (1B3, 5G6, and 36D3) were able to recognize nucleoprotein (N) (42 kDa) and four mAbs (11-2D9, 15-1G9, 17F11, and 24-1C6) recognized matrix (M) protein (24 kDa) of HIRRV. Western blot, Enzyme-linked immunosorbent assay, and indirect fluorescent antibody technique (IFAT) results indicated that the developed mAbs were specific to HIRRV without any cross-reactivity against other different fish viruses and epithelioma papulosum cyprini cells. All the mAbs comprised IgG1 heavy chain and κ light chain except 5G6, which has a heavy chain of IgG2a class. These mAbs can be very useful in development of immunodiagnosis of HIRRV infection.

Lumpy Skin Disease (LSD): Etiology, Pathogenesis, Prevention and Control

Lumpy skin disease (LSD) is one of the diseases that pose a threat to the livestock industry because it can cause large economic losses. The disease was first discovered in the country of Zambia in 1929. In Indonesia, LSD was first discovered in early 2022 in Indragiri Hulu Regency, Riau. This disease is caused by a virus belonging to the genus Capripoxvirus, subfamily chordopoxvirinae, family Poxviridae. The LSD virus has a limited host and does not infect non-ruminant hosts. A characteristic clinical symptom of LSD is the appearance of nodules on the skin. Diagnosis of this disease can be done by looking at typical clinical symptoms, laboratory tests such as virus isolation, serological tests (serum neutralization test, virus neutralization test (VNT), agar gel immune diffusion, indirect ELISA, and indirect fluorescent antibody technique (IFAT)), real time and conventional PCR, immunohistochemistry, LAMP, and IPMA. Prevention and control of LSD disease can be done in several ways such as vaccination, vector control, restriction of livestock traffic, strict quarantine and stamping out.

COMPARATIVE STUDY BETWEEN ROTA VIRUSES ISOLATED FROM DIARRHEATIC INFANT BABIES AND NEWLY BORN CALVES

Rota viruses were isolated in vero continuous cell line from infant babies and newly borne calves affected by diarrhea after treatment in every passage with 10 mg/ml of trypsin and adding 0.5 mg/ml of trypsin in the maintenance media. The isolated viruses induced distinctive and progressive type of cytopatheic effect in infected cells and highest titer was 2x10 6. TCID,50/0.1 for bovine viral isolate. The isolated 50/0.1 for human viral isolate and 2x10 » viruses were identified by indirect fluorescent antibody technique by using reference calf rotavirus antisera. Comparative study were conducted on both human and bovine viral isolate including growth in different cell culture, vero cell line was very sensitive to support growth of both viruses than secondary embryonic calf kidney cell culture, lamb testes and primary embryonic chicken fibroblast cell culture. Both viruses induced morphologically similar kind or plaques in vero cell line but plaqes formed by human isolate were larger in size about 1.5 - 2.5 mm in diameter than those of bovine isolate 1.5 - 2 mm. Cross reactive viral antigens were detected between the isolated viruses in indirect fluorescent antibody technique but not in serum neutralization test by using reference bovine rotavirus antisera.

Joint contractures responsive to immunosuppressive therapy in a girl with childhood\u2010onset systemic sclerosis double\u2010seropositive for rare anti\u2010nucleolar autoantibodies: a case report

BackgroundSystemic sclerosis (SSc; scleroderma) is an autoimmune connective tissue disease that affects the skin and subcutaneous tissue, in addition to the internal organs of the whole body. Onset in childhood is uncommon; however, both patients with childhood-onset and adult-onset SSc are positive for anti-nuclear antibodies (ANAs).Detection of SSc-related anti-nuclear antibodies is often useful for predicting clinical features, disease course, and outcomes.Case presentationA 5-year-old Japanese female manifested gradually progressive abnormal gait disturbance, regression of motor development, Raynaud’s phenomenon, and the shiny appearance of the skin of the face and extremities at age 2. On admission, she presented a mask-like appearance, loss of wrinkles and skin folds, puffy fingers, moderate diffuse scleroderma (18/51 of the modified Rodnan total skin thickness score), and contracture in the ankle and proximal interphalangeal joints. Grossly visible capillary hemorrhage on nail fold and severe abnormal capillaroscopy findings including bleeding, giant loop and disappearance of capillaryconsistent with the late phase in SSc. A skin biopsy showed fibrous thickening of the dermis, entrapment of an eccrine sweat glands, and thickened fiber. Chest high-resolution computed tomographic scanning demonstrated patchy areas of ill-defined air-space opacity and consolidation predominantly involving the posterior basilar aspects of the lower lobes presenting withinterstitial lung disease. Positive ANA (1:160 nucleolar and homogeneous nuclear staining by indirect fluorescent antibody technique) and double-seropositive for anti-Th/To and anti-PM-Scl antibodies were identified. She was diagnosed with diffuse cutaneous SSc based on the Pediatric Rheumatology European Society/American College of Rheumatology/European League Against Rheumatism Provisional Classification Criteria for Juvenile Systemic Sclerosis and was successfully treated with immunosuppressive agents, including methylprednisolone pulses and intravenous cyclophosphamide.ConclusionsWe experienced the first case of juvenile SSc with anti-PM-Scl and anti-Th/To antibodies. ILD was identified as a typical feature of patients with these autoantibodies; however, diffuse cutaneous SSc and joint contraction were uncharacteristically associated. The case showed unexpected clinical findings though the existence of SSc-related autoantibodies aids in determining possible organ involvement and to estimate the children’s outcome.

Molecular characterisation of rabies virus detected in livestock animals in the southern part of Egypt during 2018 and 2019

Brain samples were collected from 33 animals of different species, including buffalo, cattle, dog, donkey, fox and wolf, that had been suspected to be infected by rabies virus (RABV) in different geographical regions of Aswan and Luxor governorates in Egypt. The samples were submitted for histopathological examination and the presence of the nucleic acid and antigens of RABV was tested by RT-PCR and indirect fluorescent antibody technique (IFAT), respectively. Sixteen samples were found positive by all the three examinations. Three samples were selected for further study from animals in which the highest virus loads were detected. The partial sequence of the RABV N gene was determined and analysed from the samples of a buffalo, a cow and a donkey. The viruses in the samples were found to share 95-98% and 95-97% nucleotide and amino acid sequence identities, respectively. In comparison to reference sequences, a few amino acid substitutions occurred in the N protein antigenic sites I and IV in the immunodominant epitopes of the viruses detected in the cow and the donkey but not in the one from the buffalo. The phylogenetic analysis revealed that the RABVs sequenced from the samples belonged to genotype 1, Africa-4 clade, and formed two distinct sub-clades within the Egyptian clade. These findings indicate the circulation of RABV among livestock animals in the southern part of Egypt and raise public health concerns. The amino acid changes detected in this work may contribute to the antigenic diversification of RABVs.

Neospora caninum and Toxoplasma gondii as causes of reproductive losses in commercial sheep flocks from Argentina

The aim of this study is to provide preliminary data about the occurrence of Neospora caninum- and Toxoplasma gondii-related abortions and perinatal deaths in sheep from Argentina. Thirty ovine aborted foetuses and 33 perinatal deaths were submitted to the Veterinary Diagnostic Service at INTA EEA Balcarce (Argentina) during 2017–2019. A complete necropsy was performed on all specimens submitted, and foetal and placental tissues were examined. Foetal cavity fluids were collected for assessment of antibodies to N. caninum and T. gondii by indirect fluorescent antibody technique (IFAT). Placental and foetal tissue samples were collected for DNA extraction and histopathological analysis. The differential diagnosis with other causes of abortion was carried out. Of the sampled specimens, 20.63% (13/63) displayed evidence for N. caninum infection by IFAT and PCR, and in 61.5% (8/13) of the positive specimens the parasite was confirmed as the cause of abortion/perinatal death based on the presence of compatible histological lesions and/or positive immunohistochemistry test, positive PCR and/or positive IFAT, and no other infectious agents diagnosed. In contrast, T. gondii infection was confirmed in 9.52% (6/63) of the analysed specimens, but only in 2 lambs T. gondii was determined as the death cause. Neosporacaninum and T. gondii co-infections were confirmed in 4 analysed specimens (2 aborted foetuses and 2 perinatal deaths). These results demonstrated that N. caninum is efficiently transmitted and a frequent cause of ovine reproductive failure in the commercial analysed flocks compared with T. gondii. Despite T. gondii congenital infection was detected in some specimens (6/63), it was confirmed as the cause of death in only two of them. Thus, and considering the limited availability of confirmed samples, we could not determine whether toxoplasmosis is a major problem in Argentinian sheep flocks or not. More studies on a greater number of specimens from different ovine production systems under different management conditions are necessary to assess the real impact of neosporosis and toxoplasmosis in Argentina.

Seroprevalence of Trypanosoma evansi in canines by indirect fluorescent antibody test (IFAT)

An indirect fluorescent antibody technique (IFAT) was standardized to study the seroprevalence of Trypanosoma evansi among canines in and around Hyderabad, Telangana, India. The IFAT revealed an overall prevalence of anti-trypanosomal antibodies in 7.28 % (22/302) of dogs. While sex-wise incidence was not significant, the prevalence was significantly high (P=0.000) in adult dogs (10.21%) of 1–8 years of age, than in older dogs (4.21 %) of 8 years and above. No infection was recorded in puppies below one-year of age. Mongrels recorded significantly high (P=0.000) prevalence followed by crossbreds, St. Bernards, Labradors, Spitz, German Shepherds and Pomeranians in descending order. IFAT can be a simple test for screening dog populations for antibodies against T. evansi.

An abortion storm in dairy cattle associated with neosporosis in southern Brazil.

Between December 2016 and April 2017, a spate of abortions occurred in a closed dairy herd from the central eastern region of Paraná, Brazil, in which 75 cows aborted. To identify its cause, organ fragments were collected from an aborted fetus for histopathology, and the blood samples from a stillborn, 4 aborted fetuses, and 9 farm dogs for indirect fluorescent antibody technique (IFAT). These tests found multifocal non-suppurative encephalitis, periportal hepatitis, and multifocal lymphoplasmacytic myocarditis, and detected anti-Neospora antibodies in all aborted fetuses, and in 5 of the 9 dogs. DNA of Neospora caninum was detected in the brain tissue of an aborted fetus. Blood samples of 340 cows and 146 heifers showed 33.5% and 30.8% seropositivity, respectively. In this closed herd, the parasite was probably introduced by infected domesticated or wild carnivores inhabiting the farm, through the infective oocysts present in their stool.

Evaluation of current diagnostic methods for COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the agent responsible for the coronavirus disease of 2019 (COVID-19), which triggers lung failure, pneumonia, and multi-organ dysfunction. This enveloped, positive sense and single-stranded RNA virus can be transmitted through aerosol droplets, direct and indirect contacts. Thus, SARS-CoV-2 is highly contagious and has reached a pandemic level in a few months. Since COVID-19 has caused numerous human casualties and severe economic loss posing a global threat, the development of readily available, accurate, fast, and cost-effective diagnostic techniques in hospitals and in any places where humans spread the virus is urgently required. COVID-19 can be diagnosed by clinical findings and several laboratory tests. These tests may include virus isolation, nucleic acid-based molecular assays like real-time polymerase chain reactions, antigen or antibody-based immunological assays such as rapid immunochromatographic tests, enzyme-linked immunosorbent assays, immunofluorescence techniques, and indirect fluorescent antibody techniques, electrochemical sensors, etc. However, current methods should be developed by novel approaches for sensitive, specific, and accurate diagnosis of COVID-19 cases to control and prevent this outbreak. Thus, this review will cover an overview and comparison of multiple reports and commercially available kits that include molecular tests, immunoassays, and sensor-based diagnostic methods for diagnosis of COVID-19. The pros and cons of these methods and future perspectives will be thoroughly evaluated and discussed.

Possibility Of Using Urine Samples For Detection Of Bovine Viral Diarrhea Virus In Egyptian Cattle

This study aims to employ urine as an easily accessible sample for the detection of bovine viral diarrhea virus (BVDV). Thus, a periodic scan can be applied easily to reach an efficient control of the disease. A total of 86 different samples collected from 30 animals (dams n=23 and calves n=7) were raised in a farm with 1,200 cattle in the El-Fayoum district in Egypt with a case history of abortions were used for this study. All samples were subjected to virological investigation using indirect fluorescent antibody technique (IFAT) and virus neutralization tests (VNT) to detect BVDV. Isolation of the virus was achieved using MDBK cells. The isolates were confirmed using reverse transcriptase polymerase chain reaction. The BVDV was detected in nasal swabs in 63.33% and 70% using IFAT and VNT. In urine samples, the virus was detected with 46.66% and 43.33% by IFAT and VNT, respectively. BVDV was detected in most of the tissues of aborted fetuses in both techniques. Vaginal swabs revealed positive results in 53.85% and 61.54% by IFAT and VNT, respectively. Isolates were confirmed by RT-PCR by successful amplification of 288bp. Statistical analysis revealed good correlation of urine samples and other samples. In conclusion, the BVDV virus can be isolated from urine samples. To the best of our knowledge, this is the first work that provides an overview of urine usability as an alternative sample for BVD virus diagnostics in Egypt. The recommendation for further studies should elucidate on a large scale population.

T77. ASSOCIATION BETWEEN INTRACELLULAR INFECTIOUS AGENTS AND SCHIZOPHRENIA

BackgroundA number of studies have reported association between Toxoplasma gondii (T. gondii) and Chlamydia infection and the risk of schizophrenia. The aim of the present study was to compare the prevalence of T. gondii and Chlamydia infection between the schizophrenia and normal control subjects and to compare the clinical features between seropositive and seronegative schizophrenia patients.MethodsThe rate of serum reactivity to T. gondii, Chlamydia trachomatis (C. trachomatis), Chlamydia pneumonia in 96 schizophrenia and 50 control subjects was investigated using enzyme-linked immunosorbent assay and indirect fluorescent antibody technique. The clinical symptoms of the schizophrenia patients were scored with Positive and Negative Syndrome Scale and a comparative analysis was carried out.ResultsA significant positive association between immunoglobulin G (IgG) antibodies to T. gondii and C. trachomatis in schizophrenia was found, and the odds ratio of schizophrenia associated with IgG antibody was found to be 3.22 and 2.86, respectively. The Toxoplasma-seropositive schizophrenia patient had higher score on the negative subscale N1 and N7 and general psychopathology subscale G13, while C. trachomatis-seropositive schizophrenia patient had higher score on the general psychopathology subscale G10.DiscussionThe results from the present study suggest significant association between T. gondii, C. trachomatis infection and schizophrenia. In future, further studies are needed to elucidate the correlation between the two types of infection and schizophrenia.

Public Veterinary Medicine: Public Health Rabies virus variants identified in Nuevo Leon State, Mexico, from 2008 to 2015.

To identify rabies virus variants (RVVs) isolated from bats and terrestrial mammals in Nuevo Leon between 2008 and 2015 and Coahuila in 2006. RVVs isolated from 15 bats and terrestrial mammals in Nuevo Leon and from a cow (Bos taurus) in Coahuila, along with 46 reference rabies virus sequences. Antigenic characterization of the 16 isolates was performed with an indirect fluorescent antibody technique. Genomic sequencing of the nucleoprotein gene in the 16 isolates was performed with a reverse transcription PCR assay. Phylogenetic reconstruction of the 62 sequences was performed by means of Bayesian inference. 9 isolates from bats and 1 isolate from a domestic cat that became infected as a result of contact with a Mexican free-tailed bat all clustered in the lineage associated with Lasiurus spp in the Americas or the lineage associated with Tadarida brasiliensis mexicana. An isolate from a domestic dog was identified as a variant associated with the dog-coyote lineage. The RVV isolated from a fox clustered in an Arizona fox lineage. The 3 RVVs from skunks (Mephitis macroura) were placed in a lineage with variants isolated from spotted skunks (Spilogale putorius). The RVV isolated from the cow was clustered in a lineage associated with foxes in Texas and separate from the lineage for the fox from Nuevo Leon. Results reinforced the need for Mexico to implement rabies surveillance and monitoring programs for bats and wild-living terrestrial carnivores.

Neospora caninum, A potential cause of reproductive failure in dairy cows from Northern Greece.

Neospora caninum infection has been reported in a large number of intermediate hosts, such as ruminants, rabbits, mice, etc. but neosporosis has emerged as a serious disease in cattle and dogs worldwide. Abortions and other infertility issues have been reported in the infected cows, leading to great economic losses in farmers. The aim of our study was to assess N. caninum seroprevalence in dairy cattle from Northern Greece (region of Xanthi) by using the indirect fluorescent antibody technique. Blood samples were collected from 875 Holstein – Friesian dairy cows and tested for Neospora caninum antibodies. Among the cows that were studied, 184 (21.03%) were positive for N. caninum antibodies and concurrently their farms had a known previous history of infertility problems, such as abortions, increased number of artificial inseminations needed for conception, increased rate of returning to estrus and retention of fetal membranes.

Detection of lumpy skin disease virus in cattle using real-time polymerase chain reaction and serological diagnostic assays in different governorates in Egypt in 2017.

Background and Aim:Lumpy skin disease (LSD), is a highly infectious viral disease of cattle, caused by LSD virus (LSDV) which belongs to the genus Capripoxvirus of family Poxviridae. In the summer of 2017, skin lesions suggestive of LSD were observed in cattle at several governorates in Egypt. This study aimed to detect LSDV in cattle specimens using rapid serological and molecular diagnostic assays.Materials and Methods:A total of 46 skin biopsies and uncoagulated blood samples were collected from cattle with LSD suggestive clinical signs, as well as 290 coagulated whole blood samples from cattle without skin lesion in different governorates in Egypt during the summer of 2017. Skin biopsies were used for virus isolation from the chorioallantoic membrane of 11-day-old specific pathogen-free embryonated chicken eggs (SPF-ECEs). LSDV was identified using conventional polymerase chain reaction (PCR), real-time PCR (RT-PCR), and fluorescent antibody technique (FAT) with specific hyperimmune serum against LSDV. Cattle sera were examined using indirect FAT (IFAT) and indirect enzyme-linked immunosorbent assay (ELISA).Results:Skin nodules and sitfast lesions were significant clinical signs observed in all LSD suspect cattle. SPF-ECEs, from which positive isolations were made and it showed characteristic inflammatory and focal white pock lesions. The isolated viruses were identified as LSDV by FAT, conventional gel-based PCR, and RT-PCR. Among the skin biopsies and corresponding blood samples, LSDV-positive samples percentage were 39.13 and 36.95 by RT-PCR, followed 34.78 and 28.26 by conventional PCR and then 32.6 and 26.8 by FAT, respectively. The total positive percentage of LSDV antibody detected in cattle serum samples were 17.93 and 14.48 by indirect ELISA and IFAT.Conclusion:LSDV was detected and identified in skin biopsies and corresponding blood samples of naturally infected cattle, more LSDV-positive samples were detected by RT-PCR, followed by conventional PCR and then FAT. The indirect ELISA detected more antibody-positive samples than the IFAT from cattle serum samples. The RT-PCR assay is simple, sensitive, rapid, and reliable for the detection of LSDV in blood and skin nodule biopsies of suspected cattle.

A retrospective data analysis of Legionella pneumophila diagnostic procedures and their impact on patients' management: the experience of a rapid point-of-care test

We compare a conventional and a rapid point of care test (POCT) for the diagnosis of Legionella pneumophila, considering various performance criteria. We used data of patients with positive test for L. pneumophila (confirmed cases), registered by the microbiology laboratories of two hospitals in Crete, Greece. Hospital A adopts a conventional, indirect fluorescent-antibody technique and Hospital B uses a urinary antigen POCT. The mean laboratory turnaround time was 4.45 days for the conventional test and 0.11 days for POCT. A total of 24 laboratory positive cases (11 inpatients, 13 outpatients) were identified out of 905 samples taken from 751 people. The mean daily hospitalisation cost per inpatient was €79.86 for Hospital B and €127.45 for Hospital A; for the latter a much higher antibiotic treatment cost/patient was recorded. The analysis suggests that a rapid POCT for L. pneumophila could significantly decrease time to diagnosis, improve treatment and reduce hospitalisation charges.

A retrospective data analysis of Legionella pneumophila diagnostic procedures and their impact on patients' management: the experience of a rapid point-of-care test

We compare a conventional and a rapid point of care test (POCT) for the diagnosis of Legionella pneumophila, considering various performance criteria. We used data of patients with positive test for L. pneumophila (confirmed cases), registered by the microbiology laboratories of two hospitals in Crete, Greece. Hospital A adopts a conventional, indirect fluorescent-antibody technique and Hospital B uses a urinary antigen POCT. The mean laboratory turnaround time was 4.45 days for the conventional test and 0.11 days for POCT. A total of 24 laboratory positive cases (11 inpatients, 13 outpatients) were identified out of 905 samples taken from 751 people. The mean daily hospitalisation cost per inpatient was €79.86 for Hospital B and €127.45 for Hospital A; for the latter a much higher antibiotic treatment cost/patient was recorded. The analysis suggests that a rapid POCT for L. pneumophila could significantly decrease time to diagnosis, improve treatment and reduce hospitalisation charges.

Exposure of Owned Dogs and Feeding Ticks to Spotted Fever Group Rickettsioses in Central Italy.

Dogs may be useful sentinels for public health monitoring of spotted fever group rickettsioses (SFGR). The aim of this study was to determine the exposure to SFGR among dogs and feeding ticks in central Italy. A total of 344 dogs and 607 adult ticks (395 Rhipicephalus sanguineus and 212 Ixodes ricinus specimens) collected from the coats of sampled animals were included in the study. Canine serum samples were analyzed by indirect fluorescent antibody technique (IFAT) for IgG antibodies against Rickettsia conorii and Rickettsia rickettsii. All the ticks and buffy coats were processed by a PCR targeting a fragment of gltA followed by sequencing. Overall, 56 dogs (16.3%) tested positive for one or both rickettsial antigens by IFAT with endpoint titers ranging from 1:64 to 1:2048; 38 (11%) serum samples reacted against R. conorii, 46 (13.4%) reacted against R. rickettsii, and 28 (8.1%) reacted simultaneously against both rickettsial agents. All buffy coats were PCR negative. Rickettsial DNA was revealed in 39 (18.4%) I. ricinus and in 10 (2.5%) R. sanguineus specimens. The amplicons sequencing showed three SFGR, that is, R. conorii detected in 10 R. sanguineus specimens and Rickettsia helvetica and Rickettsia monacensis detected in 7 and 32 I. ricinus ticks. Nine out of the 10 R. conorii isolates were obtained from ticks collected from seronegative dogs, and one specimen from a dog tested positive for both R. rickettsii and R. conorii by immunofluorescence assay. Among the seven ticks tested positive for R. helvetica, six were recovered from the coats of seronegative dogs and one from a dog having antibodies against R. conorii; the 32 isolates of R. monacensis were obtained from 28 seronegative and 4 R. conorii/R. rickettsii-positive dogs. The results highlight the non-negligible exposure of the canine population to SFGR in the sampled areas.

S196. ASSOCIATION BETWEEN INTRACELLULAR INFECTIOUS AGENTS AND SCHIZOPHRENIA IN KOREA

BackgroundA number of studies have reported association between Toxoplasma gondii (T. gondii) and Chlamydia infection and the risk of schizophrenia. The aim of the present study was to compare the prevalence of T. gondii and Chlamydia infection between the schizophrenia and normal control subjects and to compare the clinical features between seropositive and seronegative Korean schizophrenia patients.MethodsThe rate of serum reactivity to T. gondii, Chlamydia trachomatis (C. trachomatis), Chlamydia pneumonia in 96 schizophrenia and 50 control subjects was investigated using enzyme-linked immunosorbent assay and indirect fluorescent antibody technique. The clinical symptoms of the schizophrenia patients were scored with Positive and Negative Syndrome Scale and a comparative analysis was carried out.ResultsA significant positive association between immunoglobulin G (IgG) antibodies to T. gondii and C. trachomatis in schizophrenia was found, and the odds ratio of schizophrenia associated with IgG antibody was found to be 3.22 and 2.86, respectively. The Toxoplasma-seropositive schizophrenia patient had higher score on the negative subscale N1 and N7 and general psychopathology subscale G13, while C. trachomatis-seropositive schizophrenia patient had higher score on the general psychopathology subscale G10.DiscussionThe results from the present study suggest significant association between T. gondii, C. trachomatis infection and schizophrenia. In future, further studies are needed to elucidate the correlation between the two types of infection and schizophrenia.

Preparation of a Latex Agglutination Test (LAT) as A Rapid Direct and Indirect Diagnostic Tool for Detecting Bovine Viral Diarrhea Virus (BVDV) in Cattle

Bovine viral diarrhea virus is a worldwide disease in cattle populations. Carboxylated polystyrene microspheres (0.8 nm) beads (latex) were coated using a passive adsorption method with BVDV (the Nadel strain) for the rapid indirect detection of antibodies (Abs) and with reference anti-BVDV for rapid direct detection of antigen (Ag) in cattle with reproductive disorders. Latex agglutination test (LAT) was compared with indirect fluorescent antibody technique (IFAT) and indirect enzyme linked immunosorbent assay (IELISA) by using 202 serum samples from cows suffering from reproductive disorders, apparently healthy in- contact cows and two healthy cows previously examined as negative controls and 21 liver tissue biopsies from aborted foetuses. The results show that the antibody-coated beads (Ab.c.b.) detected BVDV to 10 TCID50% and that the antigen-coated beads (Ag.c.b.) detected with antibodies to 1/128. In addition, the specificity and sensitivity were 94% and 97.97%, respectively, for Ag.c.b. and 90.9% and 90% ,respectively, for Ab.c.b. Our study confirm that the LAT is a simple, safe, specific, sensitive test and it remains an economic (low cost), accurate and rapid field test for the diagnosis of bovine viral diarrhea virus in cows as other routine serological tests IFAT and IELISA.