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1.
The monitoring of both the spread and clinical impact of Schmallenberg virus (SBV) infection within its full host range is important for the control of the epidemic and potential new outbreaks. In France, a national surveillance plan based on voluntary notifications of congenital malformations in newborn ruminants revealed that goats were the less affected host species. However, seroprevalence studies only targeted sheep and cattle, preventing accurate estimations of the real impact of SBV infection in goats. Here, a serological survey was conducted in the highest goat‐specialized region of France between June 2012 and January 2013. A total of 1490 goat sera from 50 herds were analysed by ELISA. The between‐herd and within‐herd prevalences were estimated at 62% and 13.1%, respectively. Seroprevalence was not uniformly distributed throughout the territory and markedly differed between intensive and extensive herds. The low within‐herd seroprevalence demonstrates that a large fraction of the French goat population remains susceptible to SBV infection.  相似文献   

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Over the last couple of decades, the UK experienced a substantial increase in the incidence and geographical spread of bovine tuberculosis (TB), in particular since the epidemic of foot‐and‐mouth disease (FMD) in 2001. The initiation of the Randomized Badger Culling Trial (RBCT) in 1998 in south‐west England provided an opportunity for an in‐depth collection of questionnaire data (covering farming practices, herd management and husbandry, trading and wildlife activity) from herds having experienced a TB breakdown between 1998 and early 2006 and randomly selected control herds, both within and outside the RBCT (the so‐called TB99 and CCS2005 case–control studies). The data collated were split into four separate and comparable substudies related to either the pre‐FMD or post‐FMD period, which are brought together and discussed here for the first time. The findings suggest that the risk factors associated with TB breakdowns may have changed. Higher Mycobacterium bovis prevalence in badgers following the FMD epidemic may have contributed to the identification of the presence of badgers on a farm as a prominent TB risk factor only post‐FMD. The strong emergence of contact/trading TB risk factors post‐FMD suggests that the purchasing and movement of cattle, which took place to restock FMD‐affected areas after 2001, may have exacerbated the TB problem. Post‐FMD analyses also highlighted the potential impact of environmental factors on TB risk. Although no unique and universal solution exists to reduce the transmission of TB to and among British cattle, there is an evidence to suggest that applying the broad principles of biosecurity on farms reduces the risk of infection. However, with trading remaining as an important route of local and long‐distance TB transmission, improvements in the detection of infected animals during pre‐ and post‐movement testing should further reduce the geographical spread of the disease.  相似文献   

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5.
An indirect ELISA was developed to detect antibodies specific for capripoxviruses in goat, sheep and cattle sera. Heat‐inactivated Nigerian sheeppox virus was used as the ELISA antigen. Sera obtained from sheep and goats that were experimentally infected with different capripoxvirus isolates were used to develop and evaluate the sensitivity of the ELISA. Virus neutralization indexes were determined for the experimental sera in OA3.Ts cells. The specificity of the ELISA was determined using 231 sera from capripoxvirus naïve sheep and goats from Canada. In addition, the ELISA was tested for cross‐reactivity to anti‐orf virus antibodies using orf‐reactive sera and no cross‐reactivity was observed. Using experimentally generated sera obtained from animals infected with virulent sheeppox or goatpox virus isolates, the diagnostic sensitivity of the ELISA was 96% with a diagnostic specificity of 95%, where the diagnostic sensitivity of the virus neutralization assay was 96% with a diagnostic specificity of 100%. Further evaluation of this ELISA, using 276 cattle serum samples that were positive by virus neutralization assays, revealed a diagnostic sensitivity of 88% with a specificity of 97%. These results indicated that the inactivated capripoxvirus ELISA can detect capripoxvirus‐specific antibodies in sheep, goats and cattle that have been infected with virulent capripoxvirus isolates. Non‐virulent capripoxvirus isolates, in contrast, did not elicit positive (≥1.5 Log10 neutralization index) antibody responses.  相似文献   

6.
This study was undertaken to compare the epidemiological characteristics of the 2007 foot‐and‐mouth disease outbreak in two districts of Sarpang and Zhemgang in Bhutan. Zhemgang district recorded a significantly higher cumulative incidence in all species (26.9%) as well as for cattle (29.3%) compared to Sarpang (6.5% and 7.4%, respectively). The case fatality for cattle in Zhemgang (14.1%) was significantly higher than in Sarpang (3.3%). A total of 404 cattle and 73 pigs died of FMD in Zhemgang, whereas only 21 cattle died in Sarpang. Although all four species were affected in Sarpang, no sheep or goats were affected in Zhemgang. Spatiotemporal analyses showed the existence of four significant clusters, a primary one in Sarpang and three secondary clusters in Zhemgang. The virus belonged to the PanAsia strain of the Middle‐East South‐Asia topotype (O serotype), and the strain was closely related to the PanAsia strain that circulated in Bhutan during the 2003/2004 outbreaks. The severity of FMD infection in Zhemgang district could be attributed to low vaccination coverage (36.5% in 2006 when compared to 87.6% in Sarpang), inadequate biosecurity, poor nursing care of the sick animals and delayed reporting to the livestock centre. This study highlights the ability of the PanAsia strain of the O serotype to cause unprecedented morbidity and mortality, especially in a naïve population. The study also highlights the benefits of maintaining good herd immunity in the susceptible population, through adequate vaccination coverage, to minimize the severity of infection and limit the spread of disease from infected to non‐infected herds.  相似文献   

7.
Development of point of concentration (POC) surveillance strategies for bovine tuberculosis (bTB) would facilitate global efforts to eradicate bTB. The interferon‐gamma (IFNγ) assay can detect IFNγ responses to Mycobacterium bovis in blood collected at commencement of exsanguination (COE) of experimentally challenged cattle but has not been evaluated under field conditions. The current study was aimed at determining (i) whether blood collected at COE of cattle at slaughter, under field conditions, is practical to obtain and useful for identifying cattle as IFNγ positive for bTB, (ii) whether the results of the IFNγ assay obtained at COE reliably compare with results obtained from live animals in the field, and (iii) whether the identified animal(s) originated from bTB‐infected or bTB‐exposed herds. Cattle from three risk groups were used: the highest risk group consisted of 49 cattle from 3 bTB‐infected herds; the medium risk group consisted of 24 cattle from a potentially exposed herd; and the lowest risk group consisted of 60 cattle from herds with no known history of bTB exposure. The IFNγ assay was performed on blood collected both before stunning and at COE of cattle at slaughter. An enhanced slaughter inspection for gross lesions consistent with bTB was performed on all cattle. In addition, lymph nodes were cultured for M. bovis for cattle that tested positive for bTB via the IFNγ assay and for most cattle that tested negative for bTB. Cattle, both with and without lesions consistent with bTB, were identified as positive for bTB by the IFNγ assay using blood collected at COE, but none of the positive cattle originated from the lowest risk group. The current study demonstrates that blood collected at COE of cattle is both a practical and moderately reliable sample for accessing bTB infection using the IFNγ assay.  相似文献   

8.
The dynamics of bovine besnoitiosis were studied in an area where the disease is endemic. A four‐year longitudinal study was conducted for the first time in three infected beef cattle herds located in the Urbasa‐Andía Mountains (Navarra, Spain). Each herd was visited four to seven times, and clinical and serological prevalence rates and incidence rates were estimated. Clinical inspections to identify compatible clinical signs with the disease stages were conducted at the beginning and end of the study. Serological assessment was initially performed by ELISA. Seronegative animals with clinical signs and seropositive animals with relative index per cent (RIPC) values lower than 30 that did not increase during the study period were analysed by Western blot to optimize the sensitivity and specificity of the ELISA test. Clinical prevalence rates were slightly higher (62% on average) than the seroprevalence rates (50% on average), and tissue cysts located in the vestibulum vaginae and sclera were the most frequently detected clinical signs. The proportion of seropositive animals with clinical signs varied from 16.7% to 73.6% among the herds, and 17% of cattle with clinical signs proved to be seronegative by both serological tests. An average 22% serological incidence rate was also reported in addition to clinical incidence rates that varied from 12.5% to 16.7%. Additionally, parasitemia was investigated in the herd that showed the highest clinical and seroprevalence rates. Only one PCR positive blood sample was detected. Thus, the role that blood may play in parasite transmission needs to be further investigated. Infected herds maintained both high prevalence and incidence rates in the absence of control measures and a high number of parasite carriers. Finally, economic impact studies on reproductive and productive losses associated with besnoitiosis need to be performed to implement a cost–benefit control programme.  相似文献   

9.
West Nile virus (WNV) is a mosquito‐transmitted flavivirus recognized as an emerging and re‐emerging pathogen in different countries. This study describes the monitoring of the first WNV epidemic in Spain between 2010 and 2011. Between September and December 2010, 36 outbreaks of WNV in horses were reported in three different provinces of Andalusia (southern Spain), with no apparent spread outside this area. The temporal distribution and the clinical signs observed during the WNV epidemic in Spain were, in general, similar to those reported in Europe and in the Mediterranean Basin. Morbidity, mortality and fatality rate in the affected herds were 4.6, 1.4 and 35.3%, respectively. Thirty‐six of 75 (47.4%) suspected herds investigated presented at least one IgM seropositive animal. The individual seroprevalence in unvaccinated animals from the infected holdings was 51.7%. RNA WNV lineage 1 virus was confirmed from blood and cerebrospinal fluid samples in a lethally infected horse. The entomological survey showed that the most abundant mosquito species detected in the affected area was Culex pipiens. A cross‐sectional study was carried out in non‐suspected herds between April 2010 and February 2011 in the affected area. The individual seroprevalence was 11.0%, and six of the 38 herds sampled (15.8%) presented at least one seropositive animal. The results showed active WNV circulation several months before the first outbreak was reported in horses. The seropositivity found in municipalities where clinical cases were not reported indicates a higher geographical dissemination of the virus. Significantly higher seroprevalences were detected in areas close to Morocco. Furthermore, 90 wild ruminants were tested for the presence of antibodies against WNV, but the results were all negative.  相似文献   

10.
Bulk‐tank milk (BTM) samples are frequently used to evaluate the health status of dairy livestock. A large‐scale investigation carried out in BTM samples from dairy cattle herds from a Q fever‐endemic region in Northern Spain revealed a high degree of exposure to Coxiella burnetii. This study was aimed at assessing the value of BTM samples analysis as an indicator of the C. burnetii status in dairy cattle herds. Three herds with BTM samples positive for C. burnetii by ELISA and PCR were selected, and blood, faeces and individual milk and BTM samples were analysed by serology and PCR. In spite of the high antibodies titres found in BTM samples, only one of the three farms presented an active infection by C. burnetii, as revealed by the presence of bacterial DNA in vaginal mucus and in environmental samples collected in the calving area, a seroprevalence around 40% in heifers and the seroconversion rate observed in cows. Results obtained indicated that the analysis of BTM samples is a good epidemiological tool at the population level that can be used to discriminate between seropositive and seronegative herds, but at the herd level, additional tests are necessary to evaluate whether Q fever is a potential problem in the farm. When Q fever is suspected in a cattle herd, sera from a small group of 1‐ to 3‐year‐old animals need to be analysed to investigate recent contact with C. burnetii.  相似文献   

11.
Uganda had an unusually large number of foot‐and‐mouth disease (FMD) outbreaks in 2006, and all clinical reports were in cattle. A serological investigation was carried out to confirm circulating antibodies against foot‐and‐mouth disease virus (FMDV) by ELISA for antibodies against non‐structural proteins and structural proteins. Three hundred and forty‐nine cattle sera were collected from seven districts in Uganda, and 65% of these were found positive for antibodies against the non‐structural proteins of FMDV. A subset of these samples were analysed for serotype specificity of the identified antibodies. High prevalences of antibodies against non‐structural proteins and structural proteins of FMDV serotype O were demonstrated in herds with typical visible clinical signs of FMD, while prevalences were low in herds without clinical signs of FMD. Antibody titres were higher against serotype O than against serotypes SAT 1, SAT 2 and SAT 3 in the sera investigated for serotype‐specific antibodies. Only FMDV serotype O virus was isolated from one probang sample. This study shows that the majority of the FMD outbreaks in 2006 in the region studied were caused by FMDV serotype O; however, there was also evidence of antibodies to both SAT 1 and SAT 3 in one outbreak in a herd inside Queen Elizabeth national park area.  相似文献   

12.
Foot‐and‐mouth disease (FMD) inflicts severe economic losses within infected countries and is arguably the most important trade‐restricting livestock disease in the world. In southern Africa, infected African buffaloes (Syncerus caffer) are the major reservoir of the South African Territories (SAT) types of the virus. With the progressive expansion of transfrontier conservation areas (TFCAs), the risk of FMD outbreaks is expected to increase due to a higher probability of buffalo/livestock contacts. To investigate the dynamics of FMD within and around the Great Limpopo TFCA (GLTFCA), 5 herds of buffaloes were sampled in June 2010 to characterize circulating viruses in South Africa and Zimbabwe. Three SAT‐2 and three SAT‐3 viral strains were isolated in both countries, including one that was genetically linked with a recent SAT‐2 outbreak in Mozambique in 2011. In addition, two groups of unvaccinated cattle (= 192) were serologically monitored for 1 year at the wildlife/livestock interface of Gonarezhou National Park (GNP) in Zimbabwe between April 2009 and January 2010, using the liquid‐phase blocking ELISA (LPBE) and a test for antibodies directed against non‐structural proteins (NSP). Neither clinical signs nor vaccination of cattle were reported during the study, yet a high proportion of the monitored cattle showed antibody responses against SAT‐3 and SAT‐1. Antibodies against NSP were also detected in 10% of the monitored cattle. The results of this study suggest that cattle grazing in areas adjacent to the GLTFCA can be infected by buffalo or other infected livestock and that cattle trade movements can act as efficient disseminators of FMD viruses to areas several hundred kilometres from the virus source. Current methods of surveillance of FMD at the GLTFCA interface seem insufficient to control for FMD emergence and dissemination and require urgent reassessment and regional coordination.  相似文献   

13.
The Kachia Grazing Reserve (KGR) is located in Kaduna state in north‐western Nigeria and consists of 6 contiguous blocks housing 744 defined households (HH), all engaged in livestock keeping. It is considered as a homogenous epidemiological unit and a defined study area. In 2012, all cattle and sheep of 40 selected HH were sampled to determine sero‐prevalence of antibodies to foot‐and‐mouth disease virus (FMDV) and of FMDV. The overall sero‐prevalence of antibodies to the non‐structural 3ABC protein (NSP‐3ABC ELISA) was 28.9% (380/1,315) (30.6% cattle; 16.3% sheep), and in 4.5% (62/1,380) (5% cattle; 0.6% sheep) of the examined sera FMD viral RNA could be detected by real‐time RT‐PCR (rRT‐PCR). Additionally, in 2012 and 2014 serum, epithelium and probang samples were collected from cattle in reported FMD outbreaks and the causative FMDVs were molecularly characterized. Approximately half (28/59) of the outbreak sera reacted positive in NSP‐3ABC ELISA, and 88% (52/59) of the outbreak sera contained detectable viral RNA. Overall, antibodies against five FMDV serotypes (O, A, SAT1, SAT2 and SAT3) were detected by solid phase competitive ELISA with combinations of two or more serotypes being common. Of the 21 FMDVs that could be isolated 19 were sequenced and 18 were confirmed as SAT2 (lineage VII) while one was characterized as serotype O (EA‐3 topotype). Phylogenetic analysis revealed a close relationship between Nigerian FMDV strains and strains in this region and even with strains in North‐Africa. Our findings indicate that FMD constitutes an endemic health problem to cattle rearing in the agro‐pastoralist community in the KGR and that the KGR is not a closed epidemiological unit. Insight into the local FMDV epidemiology and in the circulating FMDV serotypes/strains is of support to the relevant authorities in Nigeria when considering the need for an FMD control policy to improve animal production in grazing reserves.  相似文献   

14.
Recent outbreaks of Peste des petits ruminants (PPR) in the Marmara region of Turkey including the European part of Thrace is important due to its proximity to Europe (Greece and Bulgaria) and the potential threat of spread of PPR into mainland Europe. In order to investigate the circulation of PPRV in the region suspect clinical and necropsy samples were collected from domestic sheep (n = 211) in the Marmara region of Turkey between 2011 and 2012. PPR virus (PPRV) genome was detected in 10.4% (22 out of 211) of sheep samples by real‐time RT‐PCR, and PPR virus was isolated from lungs of two sheep that died from infection. Of the 22 positive samples nine were used for partial N‐gene amplification and sequencing. The phylogenetic analyses indicated that the virus belongs to lineage IV, the same lineage that is circulating in eastern and central part of Turkey since its first official report in 1999. In addition, samples from 100 cattle were collected to investigate potential subclinical circulation of PPRV. However all were found to be negative by real‐time RT‐PCR, and also in serological tests indicating the large ruminants were likely not exposed or infected with the virus. The impact of these findings on the potential threat of spread of PPR to Europe including the first PPR outbreak in Europe in Bulgaria on 23rd June 2018 is discussed.  相似文献   

15.
Competitive‐ELISA (c‐ELISA) is the most widely used serological test for the detection of Bluetongue virus (BTV) viral protein 7 (VP7) antibodies (Ab). However, these BTV c‐ELISAs cannot to distinguish between IgG and IgM. IgM Ab are generated shortly after the primary immune response against an infectious agent, indicating a recent infection or exposure to antigens, such as after vaccination. Because the BTV genome or anti‐VP7 Ab can be detected in ruminant blood months after infection, BTV diagnostic tools cannot discriminate between recent and old infections. In this study, we evaluated an IgM‐capture ELISA prototype to detect ruminant anti‐BTV VP7 IgM on 1,650 serum samples from cattle, sheep, or goats. Animals were BTV‐naive, infected, or/and vaccinated with BTV‐1, ‐2, ‐4, ‐8, ‐9, ‐16, or ‐27, and we also included 30 sera from cattle infected with the Epizootic haemorrhagic disease virus (EHDV) serotype 6. Results demonstrated that this ELISA kit is specific and can detect the presence of IgM with satisfactory diagnostic specificity and sensitivity from 1 to 5 weeks after BTV infection in domestic ruminants (for goats and cattle; for sheep, at least up to 24 days). The peak of anti‐VP7 IgM was reached when the level of infectious viruses and BTV RNA in blood were the highest. The possibility of detecting BTV‐RNA in IgM‐positive sera allows the amplification and sequencing of the partial RNA segment 2 (encoding the serotype specific to VP2) to determine the causative BTV serotype/strain. Therefore, BTV IgM ELISA can detect the introduction of BTV (or EHDV) in an area with BTV‐seropositive domestic animals regardless of their serological BTV status. This approach may also be of particular interest for retrospective epidemiological studies on frozen serum samples.  相似文献   

16.
In 2014, a new bluetongue virus serotype 4 (BTV ‐4) strain was detected in southern Greece and spread rapidly throughout the Balkan Peninsula and adjacent countries. Within half a year, more than 7,068 outbreaks were reported in ruminants, particularly in sheep. However, the reported morbidity and case fatality rates in ruminants varied. The pathogenesis of a Bulgarian BTV ‐4 strain isolated from sheep during the BTV ‐4 epizootic was studied in different species. Therefore, four sheep, three goats and three cattle were experimentally infected with the isolate BTV ‐4/BUL 2014/15 and monitored for clinical signs up to several weeks. Serum and whole‐blood samples were collected at regular intervals and subjected to serological and virological analyses. In this context, BTV ‐4‐specific real‐time RT ‐PCR assays were developed. The infection kinetics were similar to those known for other traditional BTV serotypes, and only mild BT ‐like clinical signs were observed in goats and sheep. In cattle, no obvious clinical signs were observed, except a transient increase in body temperature. The study results contrast with the severe clinical signs reported in sheep experimentally infected with an African BTV ‐4 strain and with the reports of BT ‐like clinical signs in a considerable proportion of different ruminant species infected with BTV ‐4 in the Balkan region and Italy. The discrepancies between the results of these animal trials and observations of BTV ‐4 infection in the field may be explained by the influence of various factors on the manifestation of BT disease, such as animal breed, fitness and virus strain, as described previously.  相似文献   

17.
Since the first reports of the Schmallenberg disease (SBD) outbreaks in late 2011, the disease has spread across Europe, affecting cattle and sheep farms. While Schmallenberg virus (SBV) causes a mild clinical disease in adults, infection of pregnant females may lead to the production of typical congenital malformations (CMFs) in their offspring. It is speculated that the immunity acquired after a SBV infection is effective in preventing further infections. However, this has not been proven in naturally infected sheep, especially if they are pregnant when reinfected. The aim of this study was to monitor the natural immunity in SBV‐infected sheep. Twenty‐four ewes from the only Spanish farm with a SBV OIE‐notified outbreak were sampled. Subsequently, nine pregnant ewes were inoculated with SBV infectious plasma under controlled conditions. Six of them were euthanized before delivery, and their fetuses were inspected for lesions indicative for the SBV infection. The three remaining ewes were allowed to deliver one lamb each. Inoculation of the lambs was scheduled at approx. 3 months after birth. All samples were analyzed for viral RNA by RT‐PCR, and for antibodies by an indirect ELISA and a virus neutralization test (VNT). The majority of the 24 ewes showed a serological reaction against SBV. The three ewes that were allowed to lamb down demonstrated variable degrees of seroconversion which corresponded to the levels of immune reaction observed in their lambs. Moreover, no viral RNA was detected, no lesions were observed in the fetuses, and no clinical signs were detected in the inoculated animals. These findings suggest that the immunity acquired by sheep following a natural SBV infection could be sufficient to stop SBV reinfection. However, vaccination could be a valuable tool to control SBV infections and associated economic losses as it affords a more uniform and predictable protection at the flock/herd level.  相似文献   

18.
Chlamydia and Chlamydia ‐like bacteria are well known to infect several organisms and may cause a wide range of diseases, particularly in ruminants. To gain insight into the prevalence and diversity of these intracellular bacteria, we applied a pan‐Chlamydiales real‐time PCR to 1,134 veterinary samples taken from 130 Tunisian ruminant herds. The true adjusted animal population‐level prevalence was 12.9% in cattle, against 8.7% in sheep. In addition, the true adjusted herd‐level prevalence of Chlamydiae was 80% in cattle and 25.5% in sheep. Chlamydiales from three family‐level lineages were detected indicating a high biodiversity of Chlamydiales in ruminant herds. Our results showed that Parachlamydia acanthamoebae could be responsible for bovine and ovine chlamydiosis in central‐eastern Tunisia. Multivariable logistic regression analysis at the animal population level indicated that strata and digestive disorders variables were the important risk factors of bovine and ovine chlamydiosis. However, origin and age variables were found to be associated with bovine and ovine chlamydiosis, respectively. At the herd level, risk factors for Chlamydia positivity were as follows: abortion and herd size for cattle against breeding system, cleaning frequency, quarantine, use of disinfectant and floor type for sheep. Paying attention to these risk factors will help improvement of control programs against this harmful zoonotic disease.  相似文献   

19.
There is an increasing concern in several European countries over the role that tuberculosis (TB)‐infected wild boar may play in the progress of bovine TB eradication campaigns. In 2004, as a consequence of the detection of a TB focus in wild boar from a National Game Reserve (NGR) located in southern Catalonia, a surveillance programme based on post‐mortem inspection for detection of macroscopic TB‐like lesions (TBLL) was initiated in the affected area. The source of infection for wild boar was linked to a tuberculous cattle herd located in the same area. Besides, the results of the surveillance programme in wild boar were used for the validation of an indirect enzyme‐linked immunosorbent assay (ELISA) specific for Mycobacterium tuberculosis complex (MTBC) IgG antibodies. Using this ELISA, a seven‐year serological study of MTBC in wild boar from the NGR was conducted in 173 animals (93 adults, 44 juveniles–yearlings and 36 piglets) culled between 2004 and 2010. ELISA results and presence of TBLL showed excellent agreement for adult and juvenile wild boar (Kappa index = 0.85; 95% CI: 0.76–0.95). Of the thirty‐eight adults, yearlings and juveniles classified as positives by the ELISA, 34 (89%) showed TBLL at necropsy. In contrast, none of the ELISA‐positive wild boar piglets (n = 20) showed TBLL, suggesting the detection of early antibody responses to the infection. Overall, this study contributes to the knowledge of wild boar humoral responses to MTBC. The results also highlight the usefulness of this serological test for wild boar TB surveillance.  相似文献   

20.
African horse sickness (AHS) is one of the most important vector‐borne viral infectious diseases of equines, transmitted mainly by Culicoides spp. The re‐emergence of Culicoides‐borne diseases in Europe, such as the recent bluetongue (BT) or Schmallenberg outbreaks, has raised concern about the potential re‐introduction and further spread of AHS virus (AHSV) in Europe. Spain has one of the largest European equine populations. In addition, its geographical, environmental and entomological conditions favour AHSV infections, as shown by the historical outbreaks in the 1990s. The establishment of risk‐based surveillance strategies would allow the early detection and rapid control of any potential AHSV outbreak. This study aimed to identify the areas and time periods that are suitable or at high risk for AHS occurrence in Spain using a GIS‐based multicriteria decision framework. Specifically risk maps for AHS occurrence were produced using a weighted linear combination of the main risk factors of disease, namely extrinsic incubation period, equine density and distribution of competent Culicoides populations. Model results revealed that the south‐western and north‐central areas of Spain and the Balearic Islands are the areas at the highest risk for AHSV infections, particularly in late summer months. Conversely, Galicia, Castile and Leon and La Rioja can be considered as low‐risk regions. This result was validated with historical AHS and BT outbreaks in Spain, and with the Culicoides vector distribution area. The model results, together with current Spanish equine production features, should provide the foundations to design risk‐based and more cost‐effective surveillance strategies for the early detection and rapid control potential of AHS outbreaks in Spain.  相似文献   

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