Development and evaluation of a blocking ELISA for serological diagnosis of equine infectious anemia.

Equine infectious anemia (EIA) is an important viral disease characterized by persistent infection in equids worldwide. Most EIA cases are life-long virus carriers with low antibody reactions and without the appearance of clinical symptoms. A serological test with high sensitivity and specificity is required to detect inapparent infection. In this study, a B-cell common epitope-based blocking ELISA (bELISA) was developed using a monoclonal antibody together with the EIAV p26 protein labelled with HRP. The test has been evaluated against the standard and with field serum samples globally. This bELISA test can be completed within 75 min, and the sensitivity is higher than those of either the AGID or one commercial cELISA kit. This bELISA assay was 8-16 times more analytically sensitive than AGID, and 2 to 4 times more analytically sensitive than one cELISA kit by testing three sera from the USA, Argentina, and China, respectively. The 353 serum samples from Argentina were tested, in comparison with AGID, the diagnostic sensitivity and specificity of our bELISA assay were 100% (154/154) and 97.0% (193/199), respectively, and the accuracy of the bELISA test was 98.3%. The bELISA test developed in this study is a rapid, sensitive, specific method for the detection of EIAV infection, and could be a promising candidate for use in the monitoring of the EIA epidemic worldwide. KEY POINTS: • A universal epitope-based blocking enzyme-linked immunosorbent assay (bELISA) was developed for detection of antibodies to EIAV. • The bELISA assay can be used to test EIAV serum samples from different regions of the world including North America, South America, Europe, and Asia. • The bELISA assay was evaluated in three different international labs and showed a better performance than other commercial kits.

Validation of an indirect in-house ELISA using synthetic peptides to detect antibodies anti-gp90 and gp45 of the equine infectious anaemia virus.

BACKGROUND: Equine infectious anaemia (EIA) is controlled by the identification of seropositive animals. The official diagnostic method is the agar gel immunodiffusion (AGID) test, which detects antibodies against a viral core protein (p26). Although AGID is inexpensive and specific, the report of results takes considerable time and the test has low analytical sensitivity. OBJECTIVE: To validate our in-house indirect ELISAgp90/45 , following the World Organization of Animal Health (OIE) criteria. STUDY DESIGN: Test validation. METHODS: Synthetic peptides gp90 and gp45 were used as antigens in ELISAgp90/45 . Tests used for validation, calibration and linear working operating range, analytical and diagnostic sensitivity and specificity, repeatability and reproducibility were assessed by comparing them with the AGID test and using 1844 equine sera grouped into five different panels. RESULTS: We were able to replace the National References Sera with our Internal Reference Sera. ELISAgp90/45 had acceptable repeatability and reproducibility. Analytical sensitivity of the ELISAgp90/45 was 800 times greater than that of AGID test for positive sera and 400 times greater for weak positive sera. ELISAgp90/45 also showed optimal analytical specificity, since no cross-reactivity was detected with antibodies against other equine viruses. One sample was positive by AGID test and negative by ELISAgp90/45. ELISAgp90/45 was performed using 243 EIA positive and 878 negative equid sera, and showed a diagnostic sensitivity of 99.59% [CI 97.73%-99.99%] and a diagnostic specificity of 90.32% [CI 88.17%-92.19%], compared to AGID test; thus, it was demonstrated to be a robust test. MAIN LIMITATIONS: Samples were derived from naturally infected equid populations showing heterogeneous clinical states: therefore, their status was uncertain and some horses were sampled more than once. The AGID test may not be the most useful gold standard. CONCLUSION: ELISAgp90/45 is a useful tool for the diagnosis of EIAV infection and meets validation requirements established by the OIE.

Diagnostic Contribution of Bronchoalveolar Lavage Sampling and Fungal Culture in a Dog With Pulmonary Coccidioidomycosis.

A 7-year-old, male neutered, Miniature Australian Shepherd from Arizona was presented for evaluation of a 3-month history of progressive cough. Thoracic radiographs revealed a focal alveolar pulmonary pattern and suspected tracheobronchial lymph node enlargement. Serum anti-Coccidioides spp. IgM/IgG antibodies were not detected by agar gel immunodiffusion performed by 2 different reference commercial veterinary laboratories approximately 3.5 and 3.75 months after respiratory tract signs were first noted. The dog failed to respond to empiric therapy with a cough suppressant and various antibiotics. Tracheobronchoscopy and bronchoalveolar lavage (BAL) were subsequently performed and cytological examination of the BAL fluid identified marked neutrophilic inflammation characterized by mildly degenerate neutrophils and no infectious organisms. Bacterial cultures were negative but fungal cultures revealed growth of Coccidioides spp. Clinical signs improved shortly after initiation of fluconazole administration and the dog achieved long-term sustained clinical remission. Here, we provide a description of a dog with pulmonary coccidioidomycosis diagnosed with fungal culture of BAL fluid. Airway sampling with cytological examination and fungal culture should be considered in dogs with persistent respiratory related clinical signs, negative antibody serology, and that have lived in or traveled to endemic areas.

Factors associated with small ruminant lentivirus infection in goat herds from Pernambuco state, Northeast region of Brazil.

Serum samples (n = 1532) were collected between May 2011 to April 2012 from goats from 76 herds (49 from dairy farms and 27 herds for genetic improvement) from three geographical regions from the state of Pernambuco, Brazil: Zona da Mata, Agreste, and Sertão. Samples were processed using agar gel immunodiffusion test, with p28 CAEV antigen. The objective was to determine the risk factors for small ruminant lentivirus (SRLV) in dairy goats and goats with high genetic value. Overall, seroprevalence was 13.7% (210/1532) [95% CI: 12-15.4%] in animals and 67.1% (51/76) [95% CI: 56.5%- 77.7%] in herds. In dairy farms the seroprevalence was 73.5% (36/49) [95% CI: 61.1%- 85.8%], and in properties with animals of high genetic value it was 55.6% (15/27) [95% CI: 36.8%- 74.3%]. Robust Poisson regression analysis adjusted by the random effect of the herd showed that risk factors were: importing bucks from another Brazilian state (prevalence ratio [PR] = 4.73 [95% CI: 2.05; 10.88]), not isolating sick animals (PR = 3.27 [95% CI: 2.24; 4.76]), and participating in fairs/animal crowding (PR = 1.52 [95% CI: 1.09; 2.11]). Prevalence results show that SRLV is present in caprine herds in the state of Pernambuco and identified risk factors are strongly related to animal transit. Considering the epidemiological situation, the first step for mitigating the consequences of this disease would be controlling animal transit.

Autoimmune gastrointestinal dysmotility following SARS-CoV-2 infection successfully treated with intravenous immunoglobulin.

BACKGROUND: Autoimmune gastrointestinal dysmotility (AGID) is a limited form of dysautonomia that can be paraneoplastic or idiopathic. Some presentations can be preceded by a viral infection. METHODS: We report a case of a 17-year-old girl that developed intractable nausea and early satiety after SARS-CoV-2 infection. KEY RESULTS: Over ten months, she required nasogastric and nasoduodenal tube feedings and finally was advanced to total parenteral nutrition to meet her caloric needs. Her α3 nicotinic ganglionic acetylcholine and anti-striational antibodies were mildly elevated. Gastrointestinal transit scintigraphy studies showed delayed gastric emptying and slowed small bowel transit. Thermoregulatory sweat test showed areas of anhidrosis consistent with autonomic sudomotor impairment. After IVIG treatment the patient's symptoms improved dramatically and she was able to tolerate full oral diet. This was reflected by improvement of her baseline transit studies and the thermoregulatory sweat test. CONCLUSIONS AND INFERENCES: This is the first report of AGID occurring after SARS-CoV-2 infection. The dramatic response to IVIG emphasizes the importance of early recognition and the reversible and treatable nature of this condition.

First study of Brucella ovis antibodies in purebred sheep flocks in the State of Parana, Brazil / [Primeiro estudo de anticorpos para Brucella ovis em rebanhos de ovinos puros de Origem, no estado do Paraná, Brasil]

Brucella ovis, a non-zoonotic species, is the etiological agent of ovine brucellosis, an infectious disease of clinical or subclinical occurrence in sheep flocks. Until then, there is no serological study of anti-Brucella ovis antibodies in purebred sheep herds. This study aimed to determine the presence of anti-Brucella ovis antibodies in purebred sheep flocks with breeding purposes from Parana State. Blood samples from 728 animals, of which 563 were females and 165 males, between 8 and 56 months of age from the six major sheep producing mesoregions of Parana, were submitted to detection of anti-Brucella ovis antibodies by the Agar Gel Immunodiffusion technique using an antigen from the bacteria Brucella ovis (Reo 198). The results indicate the presence of this disease in purebred sheep from Parana State in a low occurrence of 0.27% (2/728). The only two positive animals were rams, Santa Inês breed, from the same flock in the East Center region of Parana, without clinical disease. In conclusion, Brucella ovis is present in purebred sheep in Parana State, Brazil, and this low occurrence may have occurred due to rigorous breeding systems that may contribute to reduce the transmission of this disease.(AU)

Brucella ovis, espécie não zoonótica, é o agente etiológico da brucelose ovina, doença infecciosa de ocorrência clínica ou subclínica. Atualmente, não existe estudo sorológico de anticorpos anti-Brucella ovis em rebanhos de ovinos puros de origem. Este estudo teve como objetivo determinar a presença de anticorpos anti-Brucella ovis em rebanhos ovinos de raça pura de origem, com fins reprodutivos do estado do Paraná. Amostras de sangue de 728 animais, sendo 563 fêmeas e 165 machos, entre oito e 56 meses de idade, pertencentes a seis principais mesorregiões produtoras de ovinos no Paraná, foram submetidas à detecção de anticorpos anti-Brucella ovis pela técnica de imunodifusão em ágar gel usando-se um antígeno da bactéria Brucella ovis (Reo 198). Os resultados indicam a presença da doença em ovinos puros de origem do estado do Paraná em baixa ocorrência de 0,27% (2/728). Os dois únicos animais positivos foram reprodutores da raça Santa Inês, do mesmo rebanho da região Centro Leste do Paraná, sem manifestação clínica. Em conclusão, Brucella ovis está presente em ovinos puros de origem no estado do Paraná, e essa baixa ocorrência pode ter ocorrido devido a sistemas rigorosos de criação, que podem contribuir para a redução da transmissão dessa doença.(AU)

Identification and genetic characterization of equine infectious anemia virus in Western Balkans.

BACKGROUND: Equine infectious anemia (EIA) is a viral disease, caused by the Equine Infectious Anemia virus (EIAV) belonging to the Retroviridae family, genus Lentivirus. Horses (or equids) infected with EIAV are lifelong carriers and they remain contagious for other horses even in the absence of clinical signs. So far, EIAV infection has been reported among horses in North and South America, France, Germany, Italy, Hungary and Romania, with no publication regarding the presence of EIAV in horses in Serbia. To determine the circulation of EIAV among, approximately, the 5000 horses of the Vojvodina region, northern part of Serbia, 316 serum undergone serological testing for EIA. Then, identification and full genome sequencing using next generation sequencing was performed from one EIA positive horse. RESULTS: the 316 sera were tested with 3 different commercial agar gel immunodiffusion (AGID) tests and two different commercial enzyme-linked immunosorbent assay (ELISA). With the three AGID kits, 311 (98.4%) among the 316 tested sera were negative and only five (1.6%) sera were positive for EIA. Some discrepancies were seen for the two ELISA kits tested since one exhibited the same results as AGID test and the second gave 295 sera with negative results, five with a positive result and 16 with doubtful outcome. Phylogenetic analysis performed using the full genome sequence showed that EIAV characterized from a horse in Serbia is different from those identify so fare around the world and form a distinct and separate group together with another EIAV strain. CONCLUSIONS: This study demonstrate for the first time that EIAV is circulating at a low level in the horse population from the Northern part of Serbia. Interestingly, phylogenetic data indicates that this EIAV from the western Balkan region of Europe belongs to a new cluster.

Evaluation of Equine Infectious Anemia Virus by the Indirect Enzyme-linked Immunosorbent Assay EIA-LAB as Screening Tools in Mexico.

Equine infectious anemia is a worldwide distributed disease that affects the Equide family. Commercial effective vaccine is not available, for that reason control of the disease depends on diagnostic tools. To improve the efficiency of the diagnostic program in Cuba, LABIOFAM Group, developed an indirect enzyme-linked immunosorbent assay (ELISA), ELISA kit, to complement the diagnostic system that currently uses the agar gel immunodiffusion (AGID) kit. The ELISA AIE-LAB Kit was evaluated in a Mexican context, compared with the gold standard test Agar gel immunodiffusion, AGID AIE-LABIOFAM, and commercial AGID kit. The analytical sensitivity was determined using serial dilutions twofold of the positive control serum to establish the range of detected antibodies in relation to the cutoff value of the plate (OD 0.300). A precision study was carried out to evaluate repeatability, intermediate precision, and reproducibility by estimating the standard deviation and coefficient of variation. The precision results were satisfactory and the values of the coefficient of variation were considered adequate to guarantee an excellent consistency of the ELISA AIE-LAB. The diagnostic performance of the ELISA AIE-LAB involved the evaluation of specificity, sensitivity, and concordance in comparison with both AGID tests. The diagnostic sensitivity was 100% and the specificity 97.6%, with a very good degree of concordance (Kappa = 0.9). The results suggest that the ELISA AIE-LAB test could be used in Mexico as a diagnostic system for the detection of specific antibodies against the equine infectious anemia virus, as per current international norms.

Risk factors and detection of brucella ovis in naturally infected rams and ewes / Fatores de risco e detecção de brucella ovis em carneiros e ovelhas naturalmente infectados

The objective of this study was to verify the occurrence of ovine brucellosis using Agar Gel Immunodiffusion (AGID) and Polymerase Chain Reaction (PCR) techniques, as well as to identify the main risk factors associated with infection in sheep flocks belonging to municipalities in the microregion from Teresina, PI, Brazil. A total of 100 urine and blood samples were collected from sheep aged 6 months or older. The urine samples were submitted to conventional PCR and the blood samples were examined by the AGID technique. Of the 100 blood samples, 17 (17%) were reactive to the AGID test. In conventional PCR of 100 urine samples, six (6%) were positive. Risk factors associated to infection by B. ovis included the rearing system (OR=0.19), feed management (OR=0.05), presence of dystotic births (OR=4.50), miscarriages (OR=3.75) and source of water offered to the animals (OR=0.19). Thus, it was concluded that it is possible to detect the occurrence of animals with ovine brucellosis since PCR is a reliable method to confirm infection. Furthermore, there are risk factors associated to infection by B. ovis in the municipalities studied.

Objetivou-se verificar a ocorrência da brucelose ovina através das técnicas de Imunodifusão em Gel de Ágar (IDGA) e Reação em Cadeia da Polimerase (PCR), bem como identificar os principais fatores de risco associados à infecção nos rebanhos ovinos pertencentes a municípios da microrregião de Teresina, PI, Brasil. Foram colhidas 100 amostras de urina e de sangue de ovinos com idade superior ou igual a seis meses. As amostras de urina foram submetidas a PCR convencional e as amostras de sangue à técnica de IDGA. Das 100 amostras de sangue 17 (17%) foram reagentes ao teste de IDGA. Já na PCR convencional das 100 amostras de urina, seis (6%) foram positivas. Ressalta-se que três animais foram positivos em ambos os testes. Como fatores associados à infecção por B. ovis, observou-se o tipo de sistema de criação (OR=0,19), o manejo alimentar (OR=0,05), presença de partos distócicos (OR=4,50), abortamentos (OR=3,75) e a fonte de água fornecida aos animais (OR=0,19). Assim, conclui-se que foi possível detectar a ocorrência de animais com brucelose ovina, uma vez que a PCR é um método confirmatório. Além disso, há fatores de risco associados à infecção por B. ovis nos municípios estudados.

Risk factors and detection of brucella ovis in naturally infected rams and ewes / Fatores de risco e detecção de brucella ovis em carneiros e ovelhas naturalmente infectados

The objective of this study was to verify the occurrence of ovine brucellosis using Agar Gel Immunodiffusion (AGID) and Polymerase Chain Reaction (PCR) techniques, as well as to identify the main risk factors associated with infection in sheep flocks belonging to municipalities in the microregion from Teresina, PI, Brazil. A total of 100 urine and blood samples were collected from sheep aged 6 months or older. The urine samples were submitted to conventional PCR and the blood samples were examined by the AGID technique. Of the 100 blood samples, 17 (17%) were reactive to the AGID test. In conventional PCR of 100 urine samples, six (6%) were positive. Risk factors associated to infection by B. ovis included the rearing system (OR=0.19), feed management (OR=0.05), presence of dystotic births (OR=4.50), miscarriages (OR=3.75) and source of water offered to the animals (OR=0.19). Thus, it was concluded that it is possible to detect the occurrence of animals with ovine brucellosis since PCR is a reliable method to confirm infection. Furthermore, there are risk factors associated to infection by B. ovis in the municipalities studied.

Objetivou-se verificar a ocorrência da brucelose ovina através das técnicas de Imunodifusão em Gel de Ágar (IDGA) e Reação em Cadeia da Polimerase (PCR), bem como identificar os principais fatores de risco associados à infecção nos rebanhos ovinos pertencentes a municípios da microrregião de Teresina, PI, Brasil. Foram colhidas 100 amostras de urina e de sangue de ovinos com idade superior ou igual a seis meses. As amostras de urina foram submetidas a PCR convencional e as amostras de sangue à técnica de IDGA. Das 100 amostras de sangue 17 (17%) foram reagentes ao teste de IDGA. Já na PCR convencional das 100 amostras de urina, seis (6%) foram positivas. Ressalta-se que três animais foram positivos em ambos os testes. Como fatores associados à infecção por B. ovis, observou-se o tipo de sistema de criação (OR=0,19), o manejo alimentar (OR=0,05), presença de partos distócicos (OR=4,50), abortamentos (OR=3,75) e a fonte de água fornecida aos animais (OR=0,19). Assim, conclui-se que foi possível detectar a ocorrência de animais com brucelose ovina, uma vez que a PCR é um método confirmatório. Além disso, há fatores de risco associados à infecção por B. ovis nos municípios estudados.

Detection of Myxoma Virus in the Classical Form of Myxomatosis Using an AGID Assay: Statistical Assessment of the Assay's Diagnostic Performance.

INTRODUCTION: The aim of the study was to estimate the diagnostic sensitivity (DSe) and specificity (DSp) of an agar gel immunodiffusion (AGID) assay for detection of myxoma virus (MYXV) in the classical form of myxomatosis and to compare its diagnostic performance to that of molecular methods (IAC-PCR, OIE PCR, and OIE real-time PCR). MATERIAL AND METHODS: A panel of MYXV-positive samples of tissue homogenates with low (1 PCR unit - PCRU) and high (3,125 PCRU) virus levels and outbreak samples were used for method comparison studies. The validation parameters of the AGID assay were assessed using statistical methods. RESULTS: The AGID attained DSe of 0.65 (CI95%: 0.53-0.76), DSp of 1.00 (CI95%: 0.40-1.00), and accuracy of 0.67 (CI95%: 0.55-0.76). The assay confirmed its diagnostic usefulness primarily for testing samples containing ≥3,125 PCRU of MYXV DNA. However, in the assaying of samples containing <3,125 PCRU of the virus there was a higher probability of getting false negative results, and only molecular methods showed a 100% sensitivity for samples with low (1 PCRU) virus concentration. The overall concordance of the results between AGID and IAC-PCR was fair (ĸ = 0.40). Full concordance of the results was observed for OIE PCR and OIE real-time PCR when control reference material was analysed. CONCLUSIONS: Findings from this study suggest that AGID can be used with some limitations as a screening tool for detection of MYXV infections.

Seroprevalence of ovine brucellosis in the microregion of Teresina, Piauí, Brazil / Soroprevalência da brucelose ovina na microrregião de Teresina, Piauí

Among the diseases that affect the reproductive system of domestic animals, brucellosis in the sheep species is important because it generates significant economic losses to sheep rearing. Thus, it is a threat to the growth and productivity of sheep herds. In the face of this problem, the objective of the present research was to identify the prevalence of ovine brucellosis in herds in municipalities of the Teresina, Piauí, Brazil microregion by using the agar gel immunodiffusion assay (AGID) and indirect enzyme-linked immunosorbent assay (ELISA) serological tests. Fourteen municipalities were included in the research. Blood samples were collected from 521 pubescent animals by puncturing the jugular vein. After collection, the samples were submitted to the serological techniques, AGID and indirect ELISA, to detect anti B. ovis antibody. Of the 521 samples submitted to the AGIDtest, 23 (4.41%) were sera reagent and 498 (95.58%) negative. The indirect ELISA tests, 24 (4.61%) suspect samples and 497 (95.39%) negative samples were obtained, and there were no reagent animals in this test, only suspect. The seroprevalence of ovine brucellosis in the Teresina, Piauí microregion was 4.41%. Thus, it is possible to identify sheep with reagent serology to infection by B. ovis, that is present in municipalities in the state of Piauí, Brazil. Furthermore, AGIDwas shown to be more sensitive in detecting animals that had had contact with the etiological agent of the disease.(AU)

Dentre as enfermidades que acometem o sistema reprodutivo dos animais domésticos, a brucelose na espécie ovina tem se destacado por gerar prejuízos econômicos significativos à ovinocultura. Dessa forma, apresenta-se como uma ameaça ao crescimento e à produtividade dos rebanhos ovinos. Diante de tal problemática, objetivou-se, por meio desta pesquisa, identificar a prevalência de brucelose ovina em rebanhos pertencentes a municípios da microrregião de Teresina, Piauí, por meio dos testes sorológicos, imunodifusão em gel de ágar (IDGA) e ensaio imunoenzimático (ELISA) indireto. Quatorze municípios foram incluídos na pesquisa. Para sua execução, colheram-se, por punção venosa da jugular, amostras sanguíneas de 521 animais púberes. Após colheita, as amostras foram submetidas às técnicas sorológicas, IDGA e ELISA indireto, para a detecção de anticorpos anti-B. ovis. Das 521 amostras submetidas ao teste de IDGA, 23 (4,41%) foram sororreagentes e 498 (95,58%) negativas. Quanto ao teste ELISA indireto, obtiveram-se 24 (4,61%) amostras suspeitas e 497 (95,39%) amostras negativas, não havendo animais reagentes neste teste, apenas suspeitos. A soroprevalência da brucelose ovina na microrregião homogênea de Teresina, Piauí, foi de 4,41%. Assim, foi possível identificar ovinos com sorologia reagente à infecção por B. ovis, presente em municípios do estado do Piauí. Além disso, a IDGA mostrou-se mais sensível em detectar animais que tiveram contato com o agente etiológico da doença.(AU)

[Autoimmune autonomic ganglionopathy].

Autoimmune autonomic ganglionopathy (AAG) is an acquired immune-mediated disorder of widespread autonomic failure. Approximately half of the patients with AAG have the autoantibodies against the neuronal nicotinic acetylcholine receptor (AChR) in autonomic ganglia. These ganglionic AChR antibodies have the potential to mediate the synaptic transmission in sympathetic, parasympathetic, and enteric ganglia. Therefore, seropositive AAG patients exhibit various autonomic symptoms. Extra-autonomic manifestations (coexistence with brain involvement, sensory disturbance, endocrine disorders, autoimmune diseases and tumors) are present in many patients with AAG. The nicotinic AChRs comprise a family of abundantly expressed ligand-gated cation channels found throughout the central and peripheral nervous systems. Moreover, limited manifestations of autoimmune dysautonomia including autoimmune gastrointestinal dysmotility are newly recognized clinical entity. Although combined immunomodulatory therapy is beneficial for almost all patients with AAG, several case reports of some AAG patients with small benefit exist. This review focuses on the recent progress in the clinical approaches of AAG and its related disorders involving the role of autoantibodies and clinical practice.

Serologic Evidence for Influenza A Virus Exposure in Three Loon Species Breeding in Alaska, USA.

Limited information exists about exposure to influenza A viruses (IAVs) in many wild waterbird species, including loons. We analyzed serum samples from breeding adult Pacific (Gavia pacifica), Red-throated (Gavia stellata), and Yellow-billed (Gavia adamsii) loons sampled at three locations along the coast of Alaska, US from 2008 to 2017 to gain a better understanding of the potential role loons play in IAV ecology. We screened loon sera for IAV antibodies using three tests-blocking enzyme-linked immunosorbent assay (bELISA), agar gel immunodiffusion (AGID), and hemagglutination inhibition (HI)-and examined patterns in seroprevalence among species and sampling locations. We found evidence of IAV infection in all loon species and at all breeding locations, although concordance was imperfect among serological tests. Diagnostic tests yielded seroprevalence estimates of 24% (42/172) with bELISA, 8% (5/60) with AGID, and 6% (4/70) with HI. The IAV subtypes to which loon sera reacted using HI were consistent with those detected in waterfowl and gulls at other locations in Alaska, suggesting that loons may be exposed to IAV maintained in sympatric waterbirds. Our study provided evidence that loons inhabiting Alaska were exposed to IAV. However, given imperfect concordance among serologic tests, and relatively low seroprevalence as compared to other avian taxa exposed to IAV in Alaska, they make poor IAV surveillance targets.

Performance assessment of imported ELISA in the serodiagnosis of the enzootic bovine leukosis in herds of Pernambuco state, Brazil / Avaliação do desempenho de ELISA importado no sorodiagnóstico da leucose enzoótica bovina em rebanhos do estado de Pernambuco, Brasil

Enzootic bovine leukosis (EBL) is an infectious disease of cosmopolitan distribution and chronic character caused by a virus of the Retroviridae family, bovine leukemia virus (BLV). The epidemiological situation of EBL in Brazil has motivated studies to improve its diagnosis, based on the recommended serological techniques: agar gel immunodiffusion (AGID) and enzyme-linked immunosorbent assay (ELISA). This study was designed to evaluate the use of imported ELISA for the detection of BLV in dairy herds raised in Pernambuco, Brazil, comparing it to AGID. Blood serum samples from 327 dairy cattle from the state of Pernambuco were tested to AGID and the imported commercial ELISA CHEKIT-Leucose-serum, produced by the IDEXX® laboratory for the diagnosis of EBL. Discarding 25 inconclusive samples from one or both tests, 302 samples were analyzed, being 24.1% positive (73/302) in the AGID and 45% (136/302) in the ELISA, which compared to the AGID, a technique considered standard, presented sensitivity of 98.6%, specificity of 72% and Kappa coefficient of 0.55. The lack of agreement in the diagnostic methods was probably due to the high sensitivity of the ELISA, which makes it possible to detect antibodies even in situations with low serum levels. Although AGID has been shown to be an efficient test so far, in more advanced stages of an EBL control and eradication program, with low prevalence rates, ELISA will present better performance, due to its higher sensitivity, avoiding the permanence of animals that spread the disease in the herds.(AU)

A leucose enzoótica bovina (LEB) é uma doença infecciosa de distribuição cosmopolita e caráter crônico causada por um vírus da família Retroviridae, o vírus da leucemia bovina (VLB). A situação epidemiológica da LEB no Brasil vem motivando estudos para o aprimoramento do seu diagnóstico, tendo como base as técnicas sorológicas recomendadas: imunodifusão em gel de ágar (IDGA) e Enzyme-Linked Immunoabsorbent Assay (ELISA). Este estudo teve como objetivo avaliar o uso de ELISA importado para a detecção do VLB em rebanhos leiteiros criados em Pernambuco, Brasil, comparando-o ao IDGA. Amostras de soro sanguíneo de 327 bovinos leiteiros do estado de Pernambuco foram testadas para IDGA e ELISA comercial importado CHEKIT-Leucose-serum, produzido pelo laboratório IDEXX® para o diagnóstico da LEB. Descartadas 25 amostras inconclusivas de um ou ambos os testes, foram analisadas 302 amostras, sendo 24,1% positivas (73/302) na IDGA e 45% (136/302) no ELISA, que em relação à IDGA, técnica considerada padrão, apresentou sensibilidade de 98,6%, especificidade de 72% e coeficiente Kappa de 0.55. A falta de concordância entre os métodos diagnósticos deveu-se, provavelmente, à elevada sensibilidade do ELISA, que possibilita detectar anticorpos mesmo em situações com baixos teores séricos. Apesar da IDGA se mostrar até o momento um teste eficiente, em etapas mais avançadas de um programa de controle e erradicação da LEB, com baixos índices de prevalência, o ELISA apresentará melhor desempenho, por possuir maior sensibilidade, evitando-se a permanência de animais disseminadores da doença nos rebanhos.​(AU)

Bluetongue disease in sheep: a review / O vírus da língua azul em ovinos: uma revisão

The present review aims to show the main aspects related to bluetongue virus (BTV) infection in sheep. The bluetongue (BT) is a viral, infectious, and non-contagious disease caused by a virus (BTV) of the Orbivirus genus, transmited by a hematophagous vector of the Culicoides genus, to domestic and wild ruminants, mainly to sheep, the most susceptible species. It is caused by the association of endemic with climate conditions, with high temperatures and humidity. Economic loss is directly linked to death, abortion, weight loss, loss of milk, and meat production, and, indirectly, to the restriction on the export of animals and their by-products. The study concludes that the BTV is worldwidely spread, and probably persists due to the warm and humid climate that leads to the proliferation of Culicoides sp., being necessary to adopt measures that reduce the risk factors associated to the BTV infection.(AU)

A presente revisão objetivou apresentar os principais aspectos relacionados à infecção causada pelo vírus da língua azul em ovinos. A língua azul é uma doença viral, infecciosa e não contagiosa, causada por um vírus (BTV) do gênero Orbivírus, transmitida por meio de vetores hematófagos do gênero Culicoides a ruminantes domésticos e selvagens, principalmente aos ovinos, a espécie mais susceptível. A infecção ocorre de forma endêmica, associada a condições climáticas com elevada temperatura e umidade. As perdas econômicas estão ligadas diretamente à morte, ao abortamento, à perda de peso, à perda na produção de leite e carne, e, indiretamente, devido à restrição na exportação de animais e seus subprodutos. O estudo conclui que a língua azul está disseminada mundialmente e persiste, provavelmente, devido ao clima quente e úmido que propicia a proliferação de Culicoides sp., sendo necessário adotar medidas que diminuam os fatores de risco associados à infecção pelo vírus.(AU)

Seroprevalence of antibodies to Pestivirus infections in South Australian sheep flocks.

OBJECTIVE: Bovine viral diarrhoea virus (BVDV) and border disease virus (BDV) are of the genus Pestivirus. They are known to cause significant reproductive and production losses, with BVDV acknowledged as a major source of economic loss to the Australian cattle industry. Very little is currently known about the prevalence and effect of pestiviruses in the Australian sheep industry. The present study aimed to examine the seroprevalence and effect of both BVDV and BDV in South Australian sheep flocks. METHODS: In total, 875 breeding ewes on 29 properties were serologically tested by ELISA, AGID and VNT assays for the presence of Pestivirus-specific antibodies. RESULTS: Three (0.34%) individual animals returned serological results suggestive of previous BDV infection. All three positive animals were collected from one property, giving a property level seroprevalence of 3.45% and a within-flock seroprevalence of 10%. CONCLUSION: The results suggested that BDV infection is present, albeit at a very low incidence, in the South Australian sheep flock and BVDV infection appears to be absent. Consequently, pestiviruses are unlikely to impair production in South Australian sheep populations.

Anti-ganglionic AChR antibodies in Japanese patients with motility disorders.

BACKGROUND: The existence of several autoantibodies suggests an autoimmune basis for gastrointestinal (GI) dysmotility. Whether GI motility disorders are features of autoimmune autonomic ganglionopathy (AAG) or are related to circulating anti-ganglionic acetylcholine receptor (gAChR) antibodies (Abs) is not known. The aim of this study was to determine the associations between autonomic dysfunction, anti-gAChR Abs, and clinical features in patients with GI motility disorders including achalasia and chronic intestinal pseudo-obstruction (CIPO). METHODS: First study: retrospective cohort study and laboratory investigation. Samples from 123 patients with seropositive AAG were obtained between 2012 and 2017. Second study: prospective study. Samples from 28 patients with achalasia and 14 patients with CIPO were obtained between 2014 and 2016, and 2013 and 2017, respectively. In the first study, we analyzed clinical profiles of seropositive AAG patients. In the second study, we compared clinical profiles, autonomic symptoms, and results of antibody screening between seropositive, seronegative achalasia, and CIPO groups. RESULTS: In the first study, we identified 10 patients (8.1%) who presented with achalasia, or gastroparesis, or paralytic ileus. In the second study, we detected anti-gAChR Abs in 21.4% of the achalasia patients, and in 50.0% of the CIPO patients. Although patients with achalasia and CIPO demonstrated widespread autonomic dysfunction, bladder dysfunction was observed in the seropositive patients with CIPO as a prominent clinical characteristic of dysautonomia. CONCLUSIONS: These results demonstrate a significant prevalence of anti-gAChR antibodies in patients with achalasia and CIPO. Anti-gAChR Abs might mediate autonomic dysfunction, contributing to autoimmune mechanisms underlying these GI motility disorders.

Avaliação de um controle estratégico da artrite encefalite caprina em rebanho caprino leiteiro / Evaluation of strategic control of caprine arthritis- encephalitis in dairy herd goats

O objetivo deste trabalho foi avaliar a utilização periódica de testes de diagnóstico mais sensíveis aliados às práticas de manejo, visando ao controle eficaz da artrite encefalite caprina (CAE). Foram realizadas oito coletas de sangue em matrizes e reprodutores. Da primeira à sétima análise, as coletas foram quadrimestrais, utilizando-se os testes de imunodifusão em gel de agarose (IDGA), ensaio imunoenzimático indireto (ELISA-i) e Western Blot (WB). A oitava coleta aconteceu seis meses após a sétima, utilizando-se o WB e a reação em cadeia de polimerase (PCR). A prevalência da CAE foi de 6,8%, 14,9% e 39,2% no IDGA, ELISA-i e WB, respectivamente. Na última análise, foram detectados 0,9% de animais positivos pelo WB e 10,8% pela PCR. Apesar de não erradicarem a CAE, as medidas adotadas, aliadas à utilização periódica dos testes sorológicos e à combinação com a PCR, foram importantes para reduzir significativamente os animais soropositivos no rebanho.(AU)

The aim of this study was to evaluate the periodic use of more sensitive diagnostic tests associated to management practices for the effective control of caprine arthritis-encephalitis (CAE). We carried out eight blood samples in does and bucks. From the first to the seventh analysis, the samples were quarterly, using Agarose Gel Immunodiffusion (AGID), Enzyme linked immunosorbent assay (i-ELISA) and Western Blot (WB) tests. The eighth collection was made six months after the seventh, using the WB and Polymerase Chain Reaction (PCR). The prevalence of CAE was 6.8%, 14.9% and 39.2% in the AGID, i-ELISA and WB respectively. The last analysis detected 0.9% of animals positive by WB and 10.8% by PCR. Although they do not eradicate CAE, steps taken together with the periodic use of serological tests and the combination with PCR were important to significantly reduce positive animals in the herd.(AU)

Transmissibilidade de Lentivírus de Pequenos Ruminantes para cabritos e cabras adultas por meio de sêmen infectado experimentalmente / Transmissibility of Small Ruminants Lentivirus in kids by experimentally infected semen

A Artrite Encefalite Caprina se caracteriza por ser multissistêmica e infecciosa, causada por um lentivírus. O estudo teve como objetivo avaliar a transmissibilidade do Lentivírus Caprino, para fêmeas e sua prole, por meio de sêmen infectado experimentalmente. Para tanto, onze fêmeas livres de CAEV foram inseminadas artificialmente com sêmen de bode livre de CAEV ao qual foi adicionado CAEV-Cork para obter título infectante com carga viral em 105 TCID50/ml. (grupo experimental 1). Destas, seis obtiverem prenhez confirmada, e a sua prole (n=6) constituiu o grupo experimental 2. Duas cabras livres de CAEV foram inseminadas artificialmente com sêmen do mesmo bode, sem o inócuo viral, constituindo-se o grupo controle. O diagnóstico da infecção pelo Lentivírus Caprino, foi realizado por IDGA, cELISA e nested-PCR. As fêmeas foram monitoradas durante 210 dias pós inseminação artificial. Já as proles foram imediatamente separadas das mães após o nascimento, e monitoradas nos momentos hora zero, aos quinze dias de idade e mensalmente, até doze meses de idade. Em relação às cabras, 56,96%(9/158) apresentaram positividade para cELISA, 24,05% (38/158) foram positivas a IDGA e nenhuma para nested-PCR. Em relação aos cabritos, 11,28% (15/133) amostras positivas para nested-PCR, 5,26% (7/133) amostras positivas para IDGA e nenhum para cELISA. As proles do grupo controle apresentaram resultados negativos para as três técnicas. A positividade encontrada em nested-PCR pode indicar grande importância para identificação de animais infectados, porém soronegativos, em situações de soroconversão tardia. De acordo com os resultados, concluiu-se que há a transmissão do Lentivírus caprino para a prole e para as mães pelo sêmen infectado.(AU)

Caprine Arthritis Encephalitis is a multisystemic infectious disease, caused by a lentivirus. The objective of this study was to evaluate the transmissibility of caprine lentivirus to goats and their offspring, through experimentally infected semen. Therefore, eleven free-CAEV goats were artificially inseminated using semen from a free-CAEV buck experimentally infected with CAEV-Cork strain (experimental group one). Pregnancy was confirmed in only six goats and their offspring (n=6) constituted the experimental group two. Two free-CAEV females were artificially inseminated with semen from the same seronegative buck, without viral inoculum to constitute the control group. The diagnosis of caprine lentivirus infection was performed using AGID, cELISA and nested-PCR. All females were monitored for 210 days after artificial insemination. Kids were immediately separated from their mothers after birth, and monitored at zero time, 15 days old and monthly until 12 months old. Regarding goat samples, 56.96% (9/159) were positive in cELISA, 24.05% (38/158) were positive in IDGA and none was positive in nested-PCR. Regarding to the offspring samples, 11.28% (15/133) and 5.26% (7/133) were positive in nested-PCR and IDGA, respectively, while no sample was positive in cELISA. The control group showed no positives in the three techniques. The positivity observed to nested-PCR may show its importance to identify infected, but seronegative animals, in late seroconversion situations. According to results, the transmission of caprine lentivirus to offspring and their mothers through infected semen is possible.(AU)