RESUMEN
In September 2022, more than 50 years after its eradication from Spain, Sheep pox virus was confirmed by laboratory analysis in sheep showing characteristic lesions. This was the start of an outbreak that lasted 9 months and infected 30 farms dispersed over two different areas, Andalusia and Castilla-La Mancha. Early after the initial confirmation, an active surveillance based on clinical inspection with laboratory confirmation of sheep with clinical signs was started in restricted areas. This allowed the confirmation of Sheep pox in 22 out of 28 suspected farms, where limited numbers of sheep with mainly erythema and papules were found, indicative of early detection. Nevertheless, to improve active surveillance and stop the outbreak, clinical inspection was reinforced by laboratory analysis in all inspected farms, even when no clinically diseased sheep were detected. Although more than 35,000 oral swabs from 335 farms were analysed by real-time PCR in pools of five, only two out of six reported outbreaks in this period were detected by laboratory analysis before clinical signs were observed. Furthermore, additional insights were gained from the extensive laboratory surveillance performed on samples collected under field conditions. No evidence of Sheep pox virus infection was found in goats. Oral swabs proved to be the sample of choice for early detection in the absence of scabs and could be tested in pools of five without extensive loss in sensitivity; serology by ELISA was not useful in outbreak detection. Finally, a non-infectious genome of the virus could be detected months after cleaning and disinfection; thus, real-time PCR results should be interpreted with caution in sentinel animals during repopulation. In conclusion, the outbreak of Sheep pox virus in Spain showed that active clinical inspection with laboratory confirmation of clinically diseased sheep via oral swab testing proved a sensitive method for detection of infected farms, providing insights in laboratory surveillance that will be helpful for other countries confronted with Sheep pox outbreaks.
Asunto(s)
Capripoxvirus , Brotes de Enfermedades , Infecciones por Poxviridae , Enfermedades de las Ovejas , Animales , España/epidemiología , Brotes de Enfermedades/veterinaria , Ovinos , Infecciones por Poxviridae/veterinaria , Infecciones por Poxviridae/epidemiología , Infecciones por Poxviridae/diagnóstico , Infecciones por Poxviridae/virología , Enfermedades de las Ovejas/epidemiología , Enfermedades de las Ovejas/virología , Enfermedades de las Ovejas/diagnóstico , Capripoxvirus/genética , Capripoxvirus/aislamiento & purificación , Cabras , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Granjas , Monitoreo Epidemiológico/veterinariaRESUMEN
The serological surveillance of bluetongue in bulk tank milk is an efficient and cost-effective method for the early detection of bluetongue virus incursions in unvaccinated free areas of the disease. In addition, the availability of standardized and reliable reagents and refined diagnostic procedures with high sensitivity and specificity are essential for surveillance purposes. However, no available reference materials for bluetongue virus serological surveillance in bulk tank milk exist. This study shows the production and characterization of reference material for the implementation of a commercially available bluetongue milk ELISA test in official laboratories, as well as the evaluation of a procedure to increase the sensitivity in samples with low levels of antibodies. This procedure, based on milk protein concentration, allowed us to notably increase the ELISA test's analytical sensitivity, which is useful for milk samples from farms with low within-herd prevalence or pools of bulk tank milk samples. The standardized milk reference material produced here, together with the evaluated procedure to improve analytical sensitivity, could be applied as tools to ensure an accurate diagnosis by official laboratories in bluetongue unvaccinated free areas.
Asunto(s)
Virus de la Lengua Azul , Lengua Azul , Ensayo de Inmunoadsorción Enzimática , Proteínas de la Leche , Leche , Sensibilidad y Especificidad , Animales , Leche/virología , Leche/química , Lengua Azul/diagnóstico , Lengua Azul/virología , Virus de la Lengua Azul/inmunología , Virus de la Lengua Azul/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática/métodos , Ovinos , Bovinos , Proteínas de la Leche/análisis , Proteínas de la Leche/inmunología , Anticuerpos Antivirales/sangre , Pruebas Serológicas/métodos , Pruebas Serológicas/normas , Estándares de Referencia , FemeninoRESUMEN
BACKGROUND: West Nile Virus (WNV) is a zoonotic arbovirus worldwide spread. Seasonal WNV outbreaks occur in the Mediterranean basin since the late 1990's with ever-increasing incidence. In Southern Spain WNV is endemic, as disease foci - caused by WNV lineage 1 (WNV-L1) strains - occur every year. On the contrary, WNV-L2 is the dominant lineage in Europe, so most European WNV sequences available belong to this lineage, WNV-L1 sequences being still scarce. METHODS: To fill this gap, this study reports the genetic characterisation of 27 newly described WNV-L1 strains, involved in outbreaks affecting wild birds and horses during the last decade in South-Western Spain. RESULTS: All strains except one belong to the Western Mediterranean-1 sub-cluster (WMed-1), related phylogenetically to Italian, French, Portuguese, Moroccan and, remarkably, Senegalese strains. This sub-cluster persisted, spread and evolved into three distinguishable WMed-1 phylogenetic groups that co-circulated, notably, in the same province (Cádiz). They displayed different behaviours: from long-term persistence and rapid spread to neighbouring regions within Spain, to long-distance spread to different countries, including transcontinental spread to Africa. Among the different introductions of WNV in Spain revealed in this study, some of them succeeded to get established, some extinguished from the territory shortly afterwards. Furthermore, Spain's southernmost province, Cádiz, constitutes a hotspot for virus incursion. CONCLUSION: Southern Spain seems a likely scenario for emergence of exotic pathogens of African origin. Therefore, circulation of diverse WNV-L1 variants in Spain prompts for an extensive surveillance under a One Health approach.
RESUMEN
The African horse sickness virus (AHSV) belongs to the Genus Orbivirus, family Sedoreoviridae, and nine serotypes of the virus have been described to date. The AHSV genome is composed of ten linear segments of double-stranded (ds) RNA, numbered in decreasing size order (Seg-1 to Seg-10). Genome segment 2 (Seg-2) encodes outer-capsid protein VP2, the most variable AHSV protein and the primary target for neutralizing antibodies. Consequently, Seg-2 determines the identity of the virus serotype. An African horse sickness (AHS) outbreak in an AHS-free status country requires identifying the serotype as soon as possible to implement a serotype-specific vaccination program. Considering that nowadays 'polyvalent live attenuated' is the only commercially available vaccination strategy to control the disease, field and vaccine strains of different serotypes could co-circulate. Additionally, in AHS-endemic countries, more than one serotype is often circulating at the same time. Therefore, a strategy to rapidly determine the virus serotype in an AHS-positive sample is strongly recommended in both epidemiological situations. The main objective of this study is to describe the development and validation of three triplex real-time RT-PCR (rRT-PCR) methods for rapid AHSV serotype detection. Samples from recent AHS outbreaks in Kenia (2015-2017), Thailand (2020), and Nigeria (2023), and from the AHS outbreak in Spain (1987-1990), were included in the study for the validation of these methods.
Asunto(s)
Virus de la Enfermedad Equina Africana , Enfermedad Equina Africana , Orbivirus , Vacunas Virales , Animales , Caballos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Enfermedad Equina Africana/diagnóstico , Enfermedad Equina Africana/epidemiología , Enfermedad Equina Africana/prevención & control , Orbivirus/genética , Anticuerpos NeutralizantesRESUMEN
OBJECTIVES: To determine if measures of cervical kinematics are altered in people with acute whiplash associated disorders (WAD) and secondarily, to examine whether kinematic variables are associated with self-reported outcomes. METHODS: We recruited people with acute WAD within 15 days after a motor vehicle collision and asymptomatic control participants. All participants performed active neck movements at a self-determined velocity. Maximal range of motion (ROM), peak and mean velocity of movement, smoothness of movement, and cervical joint position error were assessed. Moreover, self-reported measures of perceived pain and disability, pain catastrophising, and fear of movement were obtained. RESULTS: Sixty people participated: 18 with acute WAD (mean age [SD] 38.7 [12.0]) and 42 as asymptomatic controls (mean age [SD] 38.4 [10.2]). Participants with acute WAD showed significantly decreased ROM in all movement directions (p < 0.0001). All participants with acute WAD showed a reduction in the mean and peak velocity of movement in all directions (p < 0.0001) and the number of velocity peaks was significantly higher (i.e., reduced smoothness of movement) in those with acute WAD in all directions (p < 0.0001). Repositioning acuity following cervical rotation was not significantly different between groups. Neck pain-related disability showed the largest number of significant associations with kinematic features, while fear of movement was not associated with measures of cervical kinematics. CONCLUSIONS: Participants with acute WAD presented with altered cervical kinematics compared to asymptomatic participants. Several measures of cervical kinematics were associated with the level of pain and disability in people with acute WAD but not their fear of movement.
Asunto(s)
Lesiones por Latigazo Cervical , Humanos , Lesiones por Latigazo Cervical/complicaciones , Dolor de Cuello/etiología , Cuello , Fenómenos Biomecánicos , Enfermedad Aguda , Percepción del DolorRESUMEN
This study described the clinical, virological, and serological responses of immunologically naïve and vaccinated horses to African horse sickness virus (AHSV) serotype 9. Naïve horses developed a clinical picture resembling the cardiac form of African horse sickness. This was characterized by inappetence, reduced activity, and hyperthermia leading to lethargy and immobility-recumbency by days 9-10 post-infection, an end-point criteria for euthanasia. After challenge, unvaccinated horses were viremic from days 3 or 4 post-infection till euthanasia, as detected by serogroup-specific (GS) real time RT-PCR (rRT-PCR) and virus isolation. Virus isolation, antigen ELISA, and GS-rRT-PCR also demonstrated high sensitivity in the post-mortem detection of the pathogen. After infection, serogroup-specific VP7 antibodies were undetectable by blocking ELISA (b-ELISA) in 2 out of 3 unvaccinated horses during the course of the disease (9-10 dpi). Vaccinated horses did not show significant side effects post-vaccination and were largely asymptomatic after the AHSV-9 challenge. VP7-specific antibodies could not be detected by the b-ELISA until day 21 and day 30 post-inoculation, respectively. Virus neutralizing antibody titres were low or even undetectable for specific serotypes in the vaccinated horses. Virus isolation and GS-rRT-PCR detected the presence of AHSV vaccine strains genomes and infectious vaccine virus after vaccination and challenge. This study established an experimental infection model of AHSV-9 in horses and characterized the main clinical, virological, and immunological parameters in both immunologically naïve and vaccinated horses using standardized bio-assays.
Asunto(s)
Virus de la Enfermedad Equina Africana , Enfermedad Equina Africana , Vacunas Virales , Enfermedad Equina Africana/prevención & control , Animales , Anticuerpos Antivirales , Caballos , SerogrupoRESUMEN
Between early October and mid-December 2018, mortalities were detected in Iberian ibex (Capra pyrenaica) populations in southern Spain. In the same region and period, bluetongue virus (BTV) circulation was also reported in sentinel and clinically affected domestic ruminant herds. Molecular analyses confirmed BTV serotype 4 (BTV-4) infection in eight Iberian ibexes from six hunting areas, and in 46 domestic ruminants from seven herds in close proximity to affected hunting estates. Histopathological analyses revealed vascular changes in several organs, pneumonia, lymphoid depletion, inflammatory mononuclear cell infiltrate and fibrosis as the most frequently observed lesions in the affected Iberian ibexes. Epidemiological and laboratory results indicate that BTV-4 was the main aetiological agent involved in outbreaks detected in Iberian ibex populations during the study period. Sequence analyses indicated that the BTV-4 strain detected in Iberian ibex had high homology (99.4%-100%) with strains isolated in livestock during the same period, and with previous isolates (≥98.9%) from Spain and Mediterranean Basin countries. Further studies are warranted to determine the impact of BTV-4 on the health status of Iberian ibex populations after the outbreaks. The inclusion of this species in the surveillance programme may be useful for early detection of BTV, especially in epidemiological scenarios at the wildlife-livestock interface.
Asunto(s)
Animales Salvajes/virología , Virus de la Lengua Azul/aislamiento & purificación , Lengua Azul/epidemiología , Rumiantes/virología , Animales , Lengua Azul/virología , Brotes de Enfermedades , Ganado , Serogrupo , España/epidemiologíaRESUMEN
In September 2017, West Nile virus (WNV) lineage 2 was detected in Catalonia (Northern Spain) in northern goshawks by passive surveillance. The phylogenetic analyses showed that it was related to the Central/Southern European strains, evidencing WNV lineage 2 spread to Western Europe. WNV local transmission was later detected in bearded vultures housed at the Wildlife Recovery center where the goshawk was transferred to. Further studies, before the following period of high mosquito activity, indicated that WNV had circulated intensively in poultry and horses but only surrounding of the area where the virus was detected. In other areas of Catalonia, circulation of flaviviruses different to WNV was identified. Public Health investigations failed to detect WNV infection in humans.
Asunto(s)
Enfermedades de las Aves/epidemiología , Brotes de Enfermedades/veterinaria , Monitoreo Epidemiológico/veterinaria , Enfermedades de los Caballos/epidemiología , Fiebre del Nilo Occidental/veterinaria , Virus del Nilo Occidental/aislamiento & purificación , Animales , Enfermedades de las Aves/virología , Pollos , Halcones , Enfermedades de los Caballos/virología , Caballos , Filogenia , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/virología , España/epidemiología , Fiebre del Nilo Occidental/epidemiología , Fiebre del Nilo Occidental/virología , Virus del Nilo Occidental/clasificación , Virus del Nilo Occidental/genéticaRESUMEN
The laboratory diagnosis of African horse sickness (AHS) is important for: (a) demonstrating freedom from infection in a population, animals or products for trade (b) assessing the efficiency of eradication policies; (c) laboratory confirmation of clinical diagnosis; (d) estimating the prevalence of AHS infection; and (e) assessing postvaccination immune status of individual animals or populations. Although serological techniques play a secondary role in the confirmation of clinical cases, their use is very important for all the other purposes due to their high throughput, ease of use and good cost-benefit ratio. The main objective of this study was to support the validation of AHS VP7 Blocking ELISA up to the Stage 3 of the World Animal Health Organization (OIE) assay validation pathway. To achieve this, a collaborative ring trial, which included all OIE Reference Laboratories and other AHS-specialist diagnostic centres, was conducted in order to assess the diagnostic performance characteristics of the VP7 Blocking ELISA. In this trial, a panel of sera of different epidemiological origin and infection status was used. Through this comprehensive evaluation we can conclude that the VP7 Blocking ELISA satisfies the OIE requirements of reproducibility. The VP7 Blocking ELISA, in its commercial version is ready to enter Stage 4 of the validation pathway (Programme Implementation). Specifically, this will require testing the diagnostic performance of the assay using contemporary serum samples collected during control campaigns in endemic countries.
Asunto(s)
Virus de la Enfermedad Equina Africana/aislamiento & purificación , Enfermedad Equina Africana/diagnóstico , Pruebas Diagnósticas de Rutina/veterinaria , Ensayo de Inmunoadsorción Enzimática/veterinaria , Enfermedades de los Caballos/diagnóstico , Animales , Antígenos Virales/sangre , Pruebas Diagnósticas de Rutina/métodos , Ensayo de Inmunoadsorción Enzimática/métodos , Caballos , Reproducibilidad de los Resultados , Proteínas del Núcleo Viral/sangreRESUMEN
West Nile disease (WND) has become a major public and veterinary health concern since the appearance of West Nile virus (WNV) in New York in 1999. The following panzootic spread in the U.S. and the recent WNV outbreaks in Europe and the Mediterranean Basin have increased interest in WND. Despite considerable investigation of WNV infection in birds, the effects of WNV on avian populations are still largely unknown. In Europe, raptors have been found to be particularly susceptible to WNV infection, but studies in birds of prey are lacking. To our knowledge, the present study is the first to report an experimental infection with WNV in Gyr-Saker hybrid falcons. We show that 10-week-old captive-reared Gyr-Saker (Falco rusticolus × Falco cherrug) hybrid falcons are susceptible to WNV infection. Neither morbidity nor mortality was observed after subcutaneous WNV inoculation with mixed extracts of non-infected mosquito salivary glands. Both the macroscopic and microscopic lesions observed were similar to those previously reported in naturally and experimentally infected North American raptors. The results obtained in the present study demonstrate that although Gyr-Saker hybrid falcons do not seem to be a good reservoir for WNV transmission via mosquito, they can become infected with WNV, develop viremia and antibodies, and are able to shed the virus.
Asunto(s)
Enfermedades de las Aves/virología , Falconiformes/genética , Predisposición Genética a la Enfermedad , Hibridación Genética , Fiebre del Nilo Occidental/veterinaria , Virus del Nilo Occidental/inmunología , Animales , Anticuerpos Antivirales/sangre , Enfermedades de las Aves/genética , Reservorios de Enfermedades/veterinaria , Femenino , Masculino , Viremia/veterinaria , Esparcimiento de Virus , Fiebre del Nilo Occidental/genéticaRESUMEN
In September 2010, an unusually high number of wild birds (partridges and pheasants) died in Cádiz in southwestern Spain. Reverse transcription PCR and virus isolation detected flavivirus infections. Complete nucleotide sequence analysis identified Bagaza virus, a flavivirus with a known distribution that includes sub-Saharan Africa and India, as the causative agent.
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Animales Salvajes/virología , Enfermedades de las Aves/epidemiología , Infecciones por Flavivirus/veterinaria , Flavivirus/aislamiento & purificación , Galliformes/virología , Animales , Enfermedades de las Aves/virología , Flavivirus/clasificación , Flavivirus/genética , Infecciones por Flavivirus/epidemiología , Infecciones por Flavivirus/virología , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , España/epidemiologíaRESUMEN
Flaviviruses of the Japanese encephalitis virus (JEV) antigenic complex, including West Nile virus (WNV), are recognized as emerging and reemerging pathogens. Circulation of flaviviruses has been recently detected in different mosquito and vertebrate species in several European countries. A serosurvey study was carried out to evaluate the circulation of WNV and other flaviviruses of the JEV antigenic complex in different wild bird species in Spain between 2006 and 2009. Seropositiviy against JEV using a competitive enzyme-linked immunosorbent assay was found in common coot, Montagu's Harrier, black kite, black vulture, Bonelli's eagle, Spanish imperial eagle, Egyptian vulture, and Eurasian spoonbill. Seropositivity to JEV antigenic complex viruses was significantly higher in samples collected during autumn compared with animals sampled during summer. Significantly higher seroprevalence was also observed in 2007 compared with 2009, whereas there were no significant differences in seropositivity among taxonomic levels, migratory versus resident behavior, body size (large vs. medium), or habitats (free-ranging vs. captivity). Neutralizing antibodies against WNV were detected in common coot and Spanish imperial eagle using a virus-neutralization test. Oral shedding of WNV was not detected in any of the Spanish imperial eagles, Egyptian vultures, Eurasian Spoonbills, Lammergeiers, and the Black vultures analyzed by means of real-time reverse transcription-polymerase chain reaction. The results indicate that WNV and others flaviviruses of the JEV antigenic group circulated in migratory and resident wild bird species in Spain between 2007 and 2008. Further studies are necessary to determine the precise role that each of these wild bird species, some of them cataloged as "near threatened," "vulnerable," or "endangered," play in the epidemiology of those viruses.