9 research outputs found
West Nile Virus (WNV): One-Health and Eco-Health Global Risks
No full textAbstract: West Nile virus (WNV) is an important zoonotic pathogen belonging to the
Flaviviridae family, which is endemic in some areas and emerging in others. WNV is
transmitted by blood-sucking mosquitoes of the genus Culicoides, Aedes, and Anopheles,
and the infection can cause different clinical symptoms. The most common and benign
illness in humans is West Nile fever (WNF), but a lethal neurological disease (WNND),
related to the neuro-invasiveness of WNV lineage 2, represents the highest health risk of
WNV infection. The neuro-clinical form is recognized in mammals (land and cetaceans),
particularly in humans (elderly or immunosuppressed) and in horses, avian species, and
wildlife animals ranging free or in a zoological setting. This review highlights the most
relevant data regarding epidemiology, virology, pathogenesis and immunity, clinical signs
and differential diagnosis, pathology and imaging, histopathology and gross pathology,
economic impact, influence of climate change, and surveillance of WNV. Climate change
has favored the wide spread of WNV in many areas of the globe and consequent One-
Health and Eco-Health emergencies, influencing the health of human beings, animals,
and ecosystems
Anemia Infettiva Equina: studio clinico, ematologico, sierologico e virologico in Muli naturalmente infetti a seguito di trattamento immunodrepressivo.
No full textL’anemia infettiva equina è un’importante malattia virale che colpisce gli equidi. L’agente eziologico responsabile è un virus a RNA appartenente alla famiglia Retroviridae genere Lentivirus. L’anemia infettiva equina (AIE) si trasmette principalmente tramite inoculazione di sangue infetto soprattutto ad opera di insetti ematofagi vettori o per inoculazione iatrogena e utilizzo di emoderivati contaminati dal virus. In Italia sono stati registrati numerosi focolai a partire dal 2007 anno in cui è iniziato il programma di sorveglianza conclusosi nel 2012. Nel corso dell’attività di sorveglianza è stata osservata una sieroprevalenza marcatamente più elevata nei muli.
Al fine di migliorare l’efficienza del programma Nazionale di Sorveglianza dell’Anemia Infettiva Equina (AIE) in Italia il Centro di Referenza per l’AIE (CRAIE) istituto presso l’Istituto Zooprofilattico Sperimentale delle Regioni Lazio e Toscana (IZSLT) ha adottato un sistema diagnostico su tre livelli basato sull’utilizzo in serie di tre test diagnostici: ELISA, AGID e Immunoblotting (IB). Dall’esame di circa 74880 campioni, principalmente raccolti da due regioni del centro Italia è emerso che 44 animali risultavano negativi al test AGID ma positivi al test ELISA/IB. La maggior parte di questi pattern di reattività sierologica (AGID negativi ELISA/IB positivi) sono state osservate nei muli. Considerata la scarsità di lavori scientifici riguardante gli aspetti epidemiologici, eziologici e clinici della malattia nei muli è stato eseguito uno studio osservazionale per meglio comprendere il ruolo del mulo nella persistenza e diffusione dell’infezione. Lo studio è stato incentrato sull’evoluzione clinica, ematologica, sierologica e virologica dell’AIE in muli naturalmente infetti a seguito di un trattamento farmacologico immunosoppressivo, volto alla riattivazione virale. Il presente lavoro rappresenta il primo studio sulla riattivazione farmacologica dell’AIE in muli naturalmente infetti
Circulation of small ruminant lentivirus in endangered goat and sheep breeds of Southern Italy
No full textAccording to the Domestic Animal Diversity Information System (DAD-IS) of the FAO, Italy has one of the largest numbers of local small ruminant breeds among European countries. In Southern Italy, namely the Campania Region, Bagnolese and Laticauda sheep breeds and Cilentana goat breeds are considered endangered according to the DAD-IS. Conservation of endangered animal breeds is a goal of the European Union (EU). However, the role of infectious diseases as risk factors for endangered breeds has rarely been considered. Small ruminant lentiviruses (SRLV) infect sheep and goats, causing slow-progressive, persistent, and debilitating diseases that can lead to animal death and productivity loss. In this study, we investigated the presence of SRLV in Bagnolese, Laticauda, and Cilentana breeds using a commercial ELISA in parallel with an in-house ELISA. The results of the two tests were in good agreement (Cohen Kappa 0.84, 95 % CI = 0.76–0.93). Discrepancies between the two tests were resolved using western blotting. In total, 430 samples were tested (248 Bagnolese, 125 Laticauda, and 57 Cilentana). The apparent prevalence rates were 12.5 %, 6.4 %, and 1.7 % in Bagnolese, Laticauda, and Cilentana, respectively. In the molecular analysis of 11 proviral partial sequences, subtypes B2 and A24 were identified in two Bagnolese herds. Owing to the beneficial role of sheep and goat breeding in marginal areas, it is important to screen the entire population and implement control/eradication of SRLV infections in conjunction with each conservation program
Evaluation of six serological ELISA kits available in Italy as screening tests for equine infectious anaemia surveillance
No full textAbstract Background ELISAs are known to have a higher diagnostic sensitivity than the agar gel immunodiffusion (AGID) when employed for serological diagnosis of equine infectious anaemia (EIA). For this purpose, an “in-house” and five commercial ELISAs available in Italy were assessed by the National Reference Centre for EIA for their analytic specificity (Sp); precocity, defined as capability of detecting first antibodies produced during a new infection; precision based on repeatability and reproducibility, estimated from the coefficient of variation (CV); accuracy, estimated from multiple K and relative Sp and sensitivity (Se). Two serum panels, positive for non-equine retroviruses and the most frequent equine viruses, were employed to measure analytic Sp. ELISA precocity was also compared to that of one “in-house” and three commercial AGID kits, employing a panel of sera, collected weekly from horses infected with modified EIA viruses. Precision and accuracy were defined using results of a panel containing positive and negative sera examined in an inter-laboratory trial with the participation of the ten Official Laboratories. Furthermore, a questionnaire was used to assess the appropriateness of each kit for routine use. Results Analytic Sp was 100%, while the 75th percentile of CVs for positive sera varied from 0.4% to 12.73% for repeatability and from 1.6% to 44.87% for reproducibility. Although CV of the negative serum was constantly high, its outcome was unaltered. Relative Se ranged from 98.2% to 100%, relative Sp was constantly 100% and multiple K ranged from 0.95 to 1. Precocity differed among the assays: three kits detected 4.8% and 42.9% positive samples on 21 days post infection (dpi), all assays detected positive samples on 28 dpi, between 47.6% and 95.2%. Precocity of ELISAs was superior to that of the AGIDs except for two assays. In view of the feedback obtained from the questionnaires, all kits were considered appropriate for routine use. Conclusion All ELISAs having high Se and precocity are preferable as a screening test in EIA surveillance programmes to the AGID tests examined. These two tests can be incorporated in a serial diagnostic pathway to improve the efficacy of a surveillance plan
Comparative Evaluation of a Multistrain Indirect ELISA Targeting Anti- p26 and gp45 Antibodies for EIAV Detection
No full textEquine Infectious Anemia Virus (EIAV), a lentivirus marked by considerable genetic variability, poses significant diagnostic challenges. Existing diagnostic tools encompass the Agar Gel Immunodiffusion Assay (AGID), enzyme-linked immunosorbent assay (ELISA), and Western blotting (WB). ELISA and AGID mainly utilize the p26 capsid protein, often sourced from the Wyoming reference strain. To broaden the range of viral proteins and strains employed in these immunoassays, we previously developed a novel p26/double-strain gp45 indirect ELISA. In this study, we evaluated the performance of this ELISA in comparison to two commercial EIAV ELISAs using Cohen’s Kappa test and Bayesian Latent Class Analysis (BLCA), a statistical method that estimates test performance without requiring a perfect reference standard. A comparison with the official classification of the sera by the Italian Veterinary Service was also performed. A total of 372 serum samples, including 96 that were positives by all three tests, were analyzed. Results from both Cohen’s Kappa test and BLCA, alongside comparison with official classifications, affirm the diagnostic reliability of the two commercial ELISAs and suggest that the novel ELISA, with its enhanced antigenic diversity, could offer an accurate and reliable diagnostic option for EIAV. This novel assay enhances existing commercial ELISAs and has the potential to strengthen routine diagnostic workflows
Validation of an indirect ELISA employing a chimeric recombinant gag and env peptide for the serological diagnosis of equine infectious anemia
No full textMonitoring for the possible introduction of Crimean-Congo haemorrhagic fever virus in Italy based on tick sampling on migratory birds and serological survey of sheep flocks
No full textEvolution of equine infectious anaemia in naturally infected mules with different serological reactivity patterns prior and after immune suppression
No full textAbstractInformation on equine infectious anaemia (EIA) in mules, including those with an equivocal reaction in agar gel immunodiffusion test (AGIDT), is scarce. For this, a study was conducted to evaluate the clinical, viral loads and pathological findings of two groups of naturally infected asymptomatic mules, respectively with a negative/equivocal and positive AGIDT reactivity, which were subjected to pharmacological immune suppression (IS). A non-infected control was included in the study that remained negative during the observation period. Throughout the whole study, even repeated episodes of recrudescence of EIA were observed in 9 infected mules, independently from their AGIDT reactivity. These events were generally characterised by mild, transient alterations, typical of the EIA acute form represented by hyperthermia and thrombocytopenia, in concomitance with viral RNA (vRNA) peaks that were higher in the Post-IS period, reaching values similar to those of horses during the clinical acute phase of EIA. Total tissue viral nucleic acid loads were greatest in animals with the major vRNA activity and in particular in those with negative/equivocal AGIDT reactivity. vRNA replication levels were around 10–1000 times lower than those reported in horses, with the animals still presenting typical alterations of EIA reactivation. Macroscopic lesions were absent in all the infected animals while histological alterations were characterised by lymphomonocyte infiltrates and moderate hemosiderosis in the cytoplasm of macrophages. On the basis of the above results, even mules with an equivocal/negative AGIDT reaction may act as EIAV reservoirs. Moreover, such animals could escape detection due to the low AGIDT sensitivity and therefore contribute to the maintenance and spread of the infection
