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Rabies is endemic in Bangladesh. To identify risk factors, a case-control study was conducted based on hospital-reported rabid animal bite (RAB) cases in domestic ruminants, 2009 - 2018. RAB cases (n = 449) and three controls per case were selected. Dogs (87.8%) and jackals (12.2%) were most often identified as biting animals. In the final multivariable model, the risk of being a RAB case was significantly higher in cattle aged >0.5-2 years (odds ratio (OR) 2.89; 95% confidence interval (CI): 1.56-5.37), >2-5 years (OR 3.63; 95% CI: 1.97-6.67) and >5 years (OR 6.42; 95% CI: 3.39-12.17) compared to those aged <0.5 years. Crossbred cattle were at higher risk of being a RAB case (OR 5.48; 95% CI: 3.56-8.42) than indigenous. Similarly, female cattle were more likely to be a RAB case (OR 1.26; 95% CI: 1.15-2.29) than males. Cattle in rural areas (OR 39.48; 95% CI: 6.14-254.00) were at a much higher risk of being RAB cases than those in urban areas. Female, crossbred and older cattle, especially in rural areas should either be managed indoors during the dog breeding season (September and October) or vaccinated. A national rabies elimination program should prioritise rural dogs for mass vaccination. Jackals should also be immunised using oral bait vaccines. Prevention of rabies in rural dogs and jackals would also reduce rabies incidence in humans.
Assuntos
Bangladesh , Mordeduras e Picadas/veterinária , Doenças dos Bovinos/virologia , Doenças do Cão/virologia , Raiva/veterinária , Animais , Bangladesh/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças do Cão/epidemiologia , Cães , Humanos , Raiva/epidemiologia , Raiva/transmissão , Estudos Retrospectivos , Fatores de Risco , ZoonosesRESUMO
Given the predisposition of South American camelids to coccidioidomycosis, we sought to describe the disease presentation in alpacas and llamas and identify potential risk factors for these species. The records of 224 llamas and alpacas that were tested for Coccidioides infection using immunodiffusion serology at the Coccidioidomycosis Serology Laboratory of the University of California, Davis, between 1990 and 2016 were examined; of those, 46 alpacas and 42 llamas had positive test results. The remaining 99 alpacas and 37 llamas were used as control groups. We found that male llamas were at increased risk for Coccidioides infection when compared with female llamas and when compared with male alpacas. South American camelids living within California were at higher risk for infection than camelids living in other states. Alpacas were more likely than llamas to have subclinical infections. We documented five cases of abortion or neonatal mortality attributable to coccidioidomycosis in alpacas. Our study demonstrates that South American camelids are susceptible to Coccidioides infection in areas where the disease is endemic, lending support to the importance of vigilance for this disease in alpacas and llamas and suggesting a possible role for these animals as sentinel species. LAY SUMMARY: We examined cases of Valley Fever and described the disease and risk factors for llamas and alpacas. Male llamas were at increased risk for infection as were animals living within California. Five alpacas had miscarriages or neonatal deaths as a result of Valley Fever infections.
RESUMO
Consumption of an adequate volume of high-quality colostrum is vital to a dairy calf's ability to survive and become a productive herd member. However, some dairy herds have reported a deficiency of colostrum production, which ranges from a low volume to no colostrum produced, by cows during fall and winter. Little information regarding this phenomenon exists. The purpose of this study was to characterize the syndrome and identify potential risk factors for low colostrum yield. A 2,500-cow Jersey dairy farm was enrolled in a prospective cohort study in May 2016, to evaluate possible effects of photoperiod, temperature, and cow factors on colostrum production. Dairy personnel were trained to collect, weigh, and evaluate colostrum quality. Information on parity, previous lactation length, previous 305-d mature-equivalent milk production, and dry period length were collected through the farm's dairy management software. Weather and photoperiod data were also collected. Over the year of enrollment, 2,988 eligible cows calved and had colostrum weights recorded and 38% were primiparous (n = 1,143), 25% were in their second lactation (n = 752), and 37% were in their third or greater lactation (n = 1,093). The overall average colostrum yield was 6.6 kg/cow in June 2016, 2.5 kg/cow in December 2016, and 4.8 kg/cow in May 2017. Multiparous cows had a larger decline in colostrum production between June and December (6.6 to 1.3 kg/cow) compared with primiparous animals (6.5 to 4.2 kg/cow). Overall, average colostrum production decreased by 0.17 kg/cow per week during this time, 0.22 kg for multiparous cows and 0.08 kg for primiparous cows. A logistic regression model was constructed for all cows to evaluate effects of cow factors on low colostrum production (<2.7 kg at first milking). Dry period length, calf sex, singleton or twin, age at freshening, month of calving and previous lactation length were significantly associated with the probability of low colostrum yield (<2.7 kg at first milking). A cross-correlation function analysis between the time series for colostrum yield and photoperiod revealed a high correlation at the time of calving and 1 mo prior, particularly for multiparous cows. A pedigree analysis showed that extreme colostrum yield (low vs. high) followed some sire lines. Low colostrum production in this herd could have an economic effect on the dairy and calf health and appears to have a strong seasonal and, potentially, a genetic component.
Assuntos
Bovinos , Colostro/metabolismo , Leite/química , Paridade , Animais , Feminino , Lactação , Gravidez , Estudos Prospectivos , Fatores de Risco , Estações do AnoRESUMO
Pollen allergies have a remarkable clinical impact all over world. Quercus pollen is the main allergen in many parts of world. Due to the health impacts caused by exposure to oak pollen, the objectives of this study are to characterise the aerobiological behaviour of Quercus pollen and to determine its potential sources as well as their transport through the atmosphere of Mexico City and surrounding areas between January 2012 and June 2015. Airborne Quercus pollen monitoring was carried out simultaneously in five zones of Mexico City. The percentage of Quercus pollen of the total pollen collected from the air showed that the highest concentration was recorded in 2014, followed by 2012. The annual seasonal variation indicated that flowering and pollen emission into the atmosphere began between February and March. The maximum concentration of Quercus pollen was reached at Cuajimalpa. In 2012, the amount of pollen grains was distributed in March and April uniformly, whilst in 2014, the largest amount of pollen was concentrated in March. In 2012 and 2014 (years with the highest pollen concentrations), corresponding intraday variations were quite similar, with a low relative maximum in the morning and the highest concentrations in the evening. The largest values were recorded in 2014, and two processes can explain these. In the afternoon, pollen from secondary forest is carried by southwesterly converging winds, increasing the pollen concentration in Cuajimalpa. In the evening, there is an additional pollen contribution from primary forest via transport by NW winds.
Assuntos
Monitoramento Ambiental , Pólen , Quercus , Alérgenos , Atmosfera , Cidades , México , Estações do AnoRESUMO
Animal health surveillance enables the detection and control of animal diseases including zoonoses. Under the EU-FP7 project RISKSUR, a survey was conducted in 11 EU Member States and Switzerland to describe active surveillance components in 2011 managed by the public or private sector and identify gaps and opportunities. Information was collected about hazard, target population, geographical focus, legal obligation, management, surveillance design, risk-based sampling, and multi-hazard surveillance. Two countries were excluded due to incompleteness of data. Most of the 664 components targeted cattle (26·7%), pigs (17·5%) or poultry (16·0%). The most common surveillance objectives were demonstrating freedom from disease (43·8%) and case detection (26·8%). Over half of components applied risk-based sampling (57·1%), but mainly focused on a single population stratum (targeted risk-based) rather than differentiating between risk levels of different strata (stratified risk-based). About a third of components were multi-hazard (37·3%). Both risk-based sampling and multi-hazard surveillance were used more frequently in privately funded components. The study identified several gaps (e.g. lack of systematic documentation, inconsistent application of terminology) and opportunities (e.g. stratified risk-based sampling). The greater flexibility provided by the new EU Animal Health Law means that systematic evaluation of surveillance alternatives will be required to optimize cost-effectiveness.
Assuntos
Doenças dos Animais/epidemiologia , Monitoramento Epidemiológico/veterinária , Animais , Bovinos , União Europeia , Aves Domésticas , Inquéritos e Questionários , Suínos , SuíçaRESUMO
In this globalized world, the spread of new, exotic and re-emerging diseases has become one of the most important threats to animal production and public health. This systematic review analyses conventional and novel early detection methods applied to surveillance. In all, 125 scientific documents were considered for this study. Exotic (n = 49) and re-emerging (n = 27) diseases constituted the most frequently represented health threats. In addition, the majority of studies were related to zoonoses (n = 66). The approaches found in the review could be divided in surveillance modalities, both active (n = 23) and passive (n = 5); and tools and methodologies that support surveillance activities (n = 57). Combinations of surveillance modalities and tools (n = 40) were also found. Risk-based approaches were very common (n = 60), especially in the papers describing tools and methodologies (n = 50). The main applications, benefits and limitations of each approach were extracted from the papers. This information will be very useful for informing the development of tools to facilitate the design of cost-effective surveillance strategies. Thus, the current literature review provides key information about the advantages, disadvantages, limitations and potential application of methodologies for the early detection of new, exotic and re-emerging diseases.
Assuntos
Controle de Doenças Transmissíveis/métodos , Controle de Doenças Transmissíveis/organização & administração , Doenças Transmissíveis Emergentes/veterinária , Diagnóstico Precoce , Monitoramento Epidemiológico , Zoonoses/diagnóstico , Zoonoses/prevenção & controle , Animais , Doenças Transmissíveis Emergentes/diagnóstico , Zoonoses/epidemiologiaRESUMO
The introduction and rapid spread of West Nile virus (WNV) into new areas such as the American continent, associated also with the severity of the disease in humans and equids has increased concerns regarding the need to better prevent and control future WNV incursions. WNV outbreaks in equids usually occur under specific climatic and environmental conditions and, typically, before detection of WNV cases in humans. Targeting surveillance strategies in areas and time periods identified as suitable for WNV outbreaks in equids may act as an early-warning system to prevent disease in both equids and humans. This study used a GIS-based framework to identify suitable areas and time periods for WNV outbreak occurrence in one of the most important areas of equid production in Spain, i.e. Castile and Leon. Methods and results presented here may help to improve the early detection and control of future WNV outbreaks in Spain and other regions.
Assuntos
Surtos de Doenças/veterinária , Sistemas de Informação Geográfica , Doenças dos Cavalos/epidemiologia , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/fisiologia , Migração Animal , Animais , Aves/fisiologia , Aves/virologia , Culex/fisiologia , Culex/virologia , Ecossistema , Doenças dos Cavalos/virologia , Cavalos , Modelos Lineares , Densidade Demográfica , Vigilância da População , Fatores de Risco , Estações do Ano , Espanha/epidemiologia , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/virologiaRESUMO
Classical swine fever (CSF) is a disease of pigs that imposes major hardship on the industry of infected regions. The recent history of CSF epidemics suggests that animal movements remain the main source of CSF virus (CSFV) infection for susceptible populations in Europe. This study presents an assessment of the risk of introducing CSFV into Spain through the importation of live susceptible animals. Results suggest that, if prevailing conditions persist, introduction of CSFV into Spain is likely to occur on average every 9 years and that introduction is almost three times more likely to occur via domestic pigs than through wild boars. The highest risk was concentrated in March and in the Northeastern provinces of Spain. Results were consistent with the time and location of previous CSFV introductions into the country. The methodology and the results presented here will contribute to improve the CSF prevention programme in Spain.
Assuntos
Agricultura , Animais Domésticos , Vírus da Febre Suína Clássica/isolamento & purificação , Peste Suína Clássica/transmissão , Medição de Risco , Meios de Transporte , Animais , Peste Suína Clássica/virologia , Simulação por Computador , Espanha , SuínosRESUMO
Classical swine fever (CSF) is a viral infectious disease of swine with significant economic impact in the affected countries due to the limitation of trade, culling of infected animals and production losses. In Latin America, CSF is endemic in several countries including Ecuador, Bolivia, Brazil and Peru. Since 2010, the National Veterinary Services of Peru have been working to better control and eradicate the disease with an intensive vaccination program. The aim of this study was to evaluate the effectiveness of the vaccination program and determine which factors are still contributing to the persistence of the disease in certain regions of Peru. We integrated the data from the vaccination campaign, the live pig movement network and other socioeconomic indicators into a multilevel logistic regression model to evaluate their association with CSF occurrence at district level. The results revealed that high vaccination coverage significantly reduces the risk of CSF occurrence (OR = 0.07), supporting the effectiveness of the vaccination program. Districts belonging to large and medium pig trade network communities (as identified with walktrap algorithm) had higher probability to CSF occurrence (OR = 2.83 and OR = 5.83, respectively). The human development index (HDI) and the presence of a slaughterhouse in the district was also significantly associated with an increased likelihood of CSF occurrence (OR = 1.52 and OR = 3.25, respectively). Districts receiving a high proportion of the movements from districts that were infected in the previous year were also at higher risk of CSF occurrence (OR = 3.30). These results should be useful to guide the prioritization of vaccination strategies and may help to design other intervention strategies (e.g., target education, movement restrictions, etc.) in high-risk areas to more rapidly advance in the eradication of CSF in Peru.
Assuntos
Peste Suína Clássica/prevenção & controle , Vacinação/veterinária , Criação de Animais Domésticos , Animais , Vírus da Febre Suína Clássica/imunologia , Erradicação de Doenças/métodos , Erradicação de Doenças/organização & administração , Peru/epidemiologia , Avaliação de Programas e Projetos de Saúde , Fatores Socioeconômicos , Suínos , Vacinas Virais/imunologia , Vacinas Virais/uso terapêuticoRESUMO
Spain has been a foot-and-mouth disease (FMD)-free country since 1986. However, the FMD epidemics that recently affected several European Union (EU) member countries demonstrated that the continent is still at high risk for FMD virus (FMDV) introduction, and that the potential consequences of those epidemics are socially and financially devastating. This paper presents a quantitative assessment of the risk of FMDV introduction into Spain. Results suggest that provinces in north-eastern Spain are at higher risk for FMDV introduction, that an FMD epidemic in Spain is more likely to occur via the import of pigs than through the import of cattle, sheep, or goats, and that a sixfold increase in the proportion of premises that quarantine pigs prior to their introduction into the operation will reduce the probability of FMDV introduction via import of live pigs into Spain by 50%. Allocation of resources towards surveillance activities in regions and types of operations at high risk for FMDV introduction and into the development of policies to promote quarantine and other biosecurity activities in susceptible operations will decrease the probability of FMD introduction into the country and will strengthen the chances of success of the Spanish FMD prevention program.
Assuntos
Febre Aftosa/epidemiologia , Febre Aftosa/prevenção & controle , Modelos Biológicos , Quarentena/veterinária , Medição de Risco , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/prevenção & controle , Comércio , Doenças das Cabras/epidemiologia , Doenças das Cabras/prevenção & controle , Cabras , Cooperação Internacional , Prevalência , Quarentena/métodos , Vigilância de Evento Sentinela/veterinária , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/prevenção & controle , Espanha/epidemiologia , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/prevenção & controleRESUMO
During the last decade, West Nile virus (WNV) outbreaks have increased sharply in both horses and human in Europe. The aims of this study were to evaluate characteristics and spatio-temporal distribution of WNV outbreaks in horses in Spain between 2010 and 2016 in order to identify the environmental variables most associated with WNV occurrence and to generate high-resolution WNV suitability maps to inform risk-based surveillance strategies in this country. Between August 2010 and November 2016, a total of 403 WNV suspected cases were investigated, of which, 177 (43.9%) were laboratory confirmed. Mean values of morbidity, mortality and case fatality rates were 7.5%, 1.6% and 21.2%, respectively. The most common clinical symptoms were as follows: tiredness/apathy, recumbency, muscular tremor, ataxia, incoordination and hyperaesthesia. The outbreaks confirmed during the last 7 years, with detection of WNV RNA lineage 1 in 2010, 2012, 2013, 2015 and 2016, suggest an endemic circulation of the virus in Spain. The spatio-temporal distribution of WNV outbreaks in Spain was not homogeneous, as most of them (92.7%) were concentrated in western part of Andalusia (southern Spain) and significant clusters were detected in this region in two non-consecutive years. These findings were supported by the results of the space-time scan statistics permutation model. A presence-only MaxEnt ecological niche model was used to generate a suitability map for WNV occurrence in Andalusia. The most important predictors selected by the Ecological Niche Modeling were as follows: mean annual temperature (49.5% contribution), presence of Culex pipiens (19.5% contribution), mean annual precipitation (16.1% contribution) and distance to Ramsar wetlands (14.9% contribution). Our results constitute an important step for understanding WNV emergence and spread in Spain and will provide valuable information for the development of more cost-effective surveillance and control programmes and improve the protection of horse and human populations in WNV-endemic areas.
Assuntos
Doenças dos Cavalos/epidemiologia , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Anticorpos Antivirais/sangue , Culex/virologia , Surtos de Doenças/veterinária , Europa (Continente) , Doenças dos Cavalos/virologia , Cavalos , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , RNA Viral/genética , Espanha/epidemiologia , Análise Espaço-Temporal , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/genética , Vírus do Nilo Ocidental/imunologiaRESUMO
African swine fever virus (ASFV) has been endemic in Sardinia since 1978, resulting in severe losses for local pig producers and creating important problems for the island's veterinary authorities. This study used a spatially explicit stochastic transmission model followed by two regression models to investigate the dynamics of ASFV spread amongst domestic pig farms, to identify geographic areas at highest risk and determine the role of different susceptible pig populations (registered domestic pigs, non-registered domestic pigs [brado] and wild boar) in ASF occurrence. We simulated transmission within and between farms using an adapted version of the previously described model known as Be-FAST. Results from the model revealed a generally low diffusion of ASF in Sardinia, with only 24% of the simulations resulting in disease spread, and for each simulated outbreak on average only four farms and 66 pigs were affected. Overall, local spread (indirect transmission between farms within a 2 km radius through fomites) was the most common route of transmission, being responsible for 98.6% of secondary cases. The risk of ASF occurrence for each domestic pig farm was estimated from the spread model results and integrated in two regression models together with available data for brado and wild boar populations. There was a significant association between the density of all three populations (domestic pigs, brado, and wild boar) and ASF occurrence in Sardinia. The most significant risk factors were the high densities of brado (OR = 2.2) and wild boar (OR = 2.1). The results of both analyses demonstrated that ASF epidemiology and infection dynamics in Sardinia create a complex and multifactorial disease situation, where all susceptible populations play an important role. To stop ASF transmission in Sardinia, three main factors (improving biosecurity on domestic pig farms, eliminating brado practices and better management of wild boars) need to be addressed.
Assuntos
Vírus da Febre Suína Africana/isolamento & purificação , Febre Suína Africana/transmissão , Surtos de Doenças/veterinária , Transmissão de Doença Infecciosa/veterinária , Sus scrofa/virologia , Doenças dos Suínos/transmissão , Febre Suína Africana/virologia , Animais , Fazendas , Itália/epidemiologia , Fatores de Risco , Suínos , Doenças dos Suínos/virologiaRESUMO
Given the predisposition of dogs to coccidioidomycosis, identification of high-risk regions for coccidioidomycosis in dogs may improve early recognition of emerging human disease. We sought to identify risk factors for canine coccidioidomycosis and to produce a risk map for coccidioidomycosis occurrence. Forty-one dogs seen at the Veterinary Medical Teaching Hospital at the University of California, Davis, between 2005 and 2013 with coccidioidomycosis were identified together with a control population of 79 dogs. Owners were surveyed about potential risk factors including younger age, digging behaviour, and travel to Arizona or the California central valley. Risk factors were analysed using logistic regression analysis. Outcomes were used to generate a risk map for coccidioidomycosis in California. There was a significant correlation between the reported rate of coccidioidomycosis in humans and our risk map for canine coccidioidomycosis in California, supporting the idea of dogs as sentinels for emerging geographic areas for coccidioidomycosis in humans.
Assuntos
Coccidioidomicose/veterinária , Doenças do Cão/epidemiologia , Animais , California/epidemiologia , Estudos de Casos e Controles , Coccidioides/isolamento & purificação , Coccidioidomicose/epidemiologia , Coccidioidomicose/microbiologia , Doenças do Cão/microbiologia , Cães , Feminino , Mapeamento Geográfico , Masculino , Fatores de Risco , Análise EspacialRESUMO
White spot disease (WSD), caused by the white spot syndrome virus, is currently one of the primary causes of mortality and economic losses in the shrimp farming industry worldwide. In Mexico, shrimp production is one of the most important primary activities generating an annual income of USD 711 million. However, WSD introduction in 1999 had a devastating impact for the Mexican shrimp industry. The aim of this study was to characterize the WSD spatio-temporal patterns and to identify the primary risk factors contributing to WSD occurrence from 2005 to 2011 in Sinaloa, Mexico. We used data collected by the 'Comité Estatal de Sanidad Acuícola de Sinaloa' from 2005 to 2011 regarding WSD outbreaks as well as environmental, production and husbandry factors at farm level. The spatio-temporal patterns of WSD were described using space-time scan statistics. The effect of 52 variables on the time to WSD outbreak occurrence was assessed using a multivariable Cox proportional hazards model. Results reveal that WSD risk and survival time were not homogeneously distributed as suggested by the significant clusters obtained using the space-time permutation model and the space-time exponential model, respectively. The Cox model revealed that the first production cycle [hazard ratio (HR) = 11.31], changes from 1 to 1.4°C of temperature oscillation caused by 'El Niño'/'La Niña' events (HR = 1.44) and high average daily growths (HR = 1.26) were significantly associated with lower survival (i.e. shorter time to WSD outbreak) on farm. Conversely, shrimp weight at the moment of the outbreak (HR = 0.159), changes from -0.9 to -0.5°C of temperature oscillation caused by 'El Niño'/'La Niña' events (HR = 0.540), high superficial water temperature during the pound stocking (HR = 0.823) and high (>100) number of days of culture (HR = 0.830) were factors associated with higher survival. Results are expected to inform the design of risk-based, intervention strategies to minimize the impact of WSD in Mexico.
Assuntos
Aquicultura , Penaeidae/virologia , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , México , Fatores de RiscoRESUMO
Be-FAST is a computer program based on a time-spatial stochastic spread mathematical model for studying the transmission of infectious livestock diseases within and between farms. The present work describes a new module integrated into Be-FAST to model the economic consequences of the spreading of classical swine fever (CSF) and other infectious livestock diseases within and between farms. CSF is financially one of the most damaging diseases in the swine industry worldwide. Specifically in Spain, the economic costs in the two last CSF epidemics (1997 and 2001) reached jointly more than 108 million euros. The present analysis suggests that severe CSF epidemics are associated with significant economic costs, approximately 80% of which are related to animal culling. Direct costs associated with control measures are strongly associated with the number of infected farms, while indirect costs are more strongly associated with epidemic duration. The economic model has been validated with economic information around the last outbreaks in Spain. These results suggest that our economic module may be useful for analysing and predicting economic consequences of livestock disease epidemics.
Assuntos
Peste Suína Clássica/economia , Surtos de Doenças/veterinária , Modelos Econômicos , Software , Doenças dos Suínos/economia , Animais , Peste Suína Clássica/epidemiologia , Peste Suína Clássica/transmissão , Simulação por Computador , Custos e Análise de Custo , Surtos de Doenças/economia , Gado , Espanha/epidemiologia , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/transmissãoRESUMO
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.
Assuntos
Vírus da Doença Equina Africana , Doença Equina Africana/epidemiologia , Doença Equina Africana/prevenção & controle , Animais , Ceratopogonidae/virologia , Surtos de Doenças/veterinária , Cavalos/virologia , Insetos Vetores , Estações do Ano , Ovinos , Espanha/epidemiologiaRESUMO
Despite the implementation of control efforts and funds to fight against the disease, African swine fever (ASF) has been present in Sardinia since 1978. It has caused serious problems for both the industrial pig sector and the regional authorities in Sardinia, as well as the economy of Italy and the European Union, which annually supports the costly eradication programme. During this time, ASF has persisted, especially in the central-east part of Sardinia where almost 75% of the total outbreaks are concentrated. The Sardinian pig sector is clearly divided into two categories based on the specialization and industrialization of production: industrial farms, which represents only 1.8% of the farms in the island and non-professional holdings, which are comprised of small producers (90% of pig holdings have <15 pigs) and apply little to no biosecurity measures. Additionally, illegally raised pigs are still bred in free-ranging systems in certain isolated parts of the island, despite strict regulations. The illegal raising of pigs, along with other high-risk management practices (e.g., use of communal areas) are likely the primary reasons for endemic persistence of the virus in this area. The compensation provided to the farmers, and other aspects of the eradication programme have also negatively influenced eradication efforts, indicating that socio-cultural and economic factors play an important role in the epidemiology of ASF on the island. The aim of this study was to comprehensively review the evolution of the 35-year presence of ASF in Sardinia, including control measures, and the environmental and socio-economic factors that may have contributed to disease endemicity on the island. The present review highlights the need for a coordinated programme that considers these socio-economic and environmental factors and includes an assessment of new cost-effective control strategies and diagnostic tools for effectively controlling ASF in Sardinia.
Assuntos
Febre Suína Africana/epidemiologia , Febre Suína Africana/etiologia , Febre Suína Africana/prevenção & controle , Vírus da Febre Suína Africana/isolamento & purificação , Criação de Animais Domésticos/métodos , Animais , Erradicação de Doenças/métodos , Surtos de Doenças/veterinária , Itália/epidemiologia , Fatores de Risco , Fatores Socioeconômicos , SuínosRESUMO
Live fish movement is considered as having an important role in the transmission of infectious diseases. For that reason, interventions for cost-effective disease prevention and control rely on a sound understanding of the patterns of live fish movements in a region or country. Here, we characterize the network of live fish movements in the Irish salmonid farming industry during 2013, using social network analysis and spatial epidemiology methods, and identify interventions to limit the risk of disease introduction and spread. In the network there were 62 sites sending and/or receiving fish, with a total of 130 shipments (84 arcs) comprising approx. 17.2 million fish during the year. Atlantic salmon shipments covered longer distances than trout shipments, with some traversing the entire country. The average shipment of Atlantic salmon was 146,186 (SD 194,344) fish, compared to 77,928 (127,009) for trout, however, variability was high. There were 3 periods where shipments peaked (February-April, June-September, and November), which were related to specific stages of fish. The network was disconnected and had two major weak components, the first one with 39 nodes (mostly Atlantic salmon sites), and the second one with 10 nodes (exclusively trout sites). Correlation between in and out-degree at each site and assortativity coefficient were slightly low and non-significant: -0.08 (95% CI: -0.22, 0.06) and -0.13 (95% CI: -0.36, 0.08), respectively, indicating random mixing with regard to node degree. Although competing models also produced a good fit to degree distribution, it is likely that the network possesses both small-world and scale-free topology. This would facilitate the spread and persistence of infection in the salmon production system, but would also facilitate the design of risk-based surveillance strategies by targeting hubs, bridges or cut-points. Using Infomap community detection algorithms, 2 major communities were identified within the giant weak component, which were linked by only 4 nodes. Communities found had no correspondence with geographical zones within the country, which could potentially hinder the implementation of zoning strategies for disease control and eradication. Three significant spatial clusters of node centrality measures were detected, two in county Donegal (betweenness and outcloseness) and one in county Galway (incloseness), highlighting the importance of these locations as hot spots of highly central sites with a higher potential for both introduction and spread of infection. These results will assist in the design and implementation of measures to reduce the sanitary risks emerging from live fish trade within Ireland.
Assuntos
Aquicultura/métodos , Doenças dos Peixes/prevenção & controle , Salmonidae , Meios de Transporte , Animais , Irlanda , Modelos Teóricos , Medição de Risco , Rede Social , Análise EspacialRESUMO
The presence of African swine fever (ASF) in the Caucasus region and Russian Federation has increased concerns that wild boars may introduce the ASF virus into the European Union (EU). This study describes a semi-quantitative approach for evaluating the risk of ASF introduction into the EU by wild boar movements based on the following risk estimators: the susceptible population of (1) wild boars and (2) domestic pigs in the country of origin; the outbreak density in (3) wild boars and (4) domestic pigs in the countries of origin, the (5) suitable habitat for wild boars along the EU border; and the distance between the EU border and the nearest ASF outbreak in (6) wild boars or (7) domestic pigs. Sensitivity analysis was performed to identify the most influential risk estimators. The highest risk was found to be concentrated in Finland, Romania, Latvia and Poland, and wild boar habitat and outbreak density were the two most important risk estimators. Animal health authorities in at-risk countries should be aware of these risk estimators and should communicate closely with wild boar hunters and pig farmers to rapidly detect and control ASF.
Assuntos
Febre Suína Africana/epidemiologia , Sus scrofa/virologia , Vírus da Febre Suína Africana/isolamento & purificação , Animais , Surtos de Doenças , Europa (Continente)/epidemiologia , União Europeia , Fatores de Risco , Federação Russa/epidemiologia , SuínosRESUMO
Aujeszky's disease (AD) causes significant economic losses in the Spanish pig sector due to import trade restrictions imposed by disease-free countries. Most regions of Spain have achieved 'low AD prevalence' status as a result of an intensive national AD eradication programme involving vaccination and other measures. However, to achieve AD-free status that would eliminate trade restrictions, vaccination must be stopped. For this final stage of eradication, up to date and reliable estimates of the risk of AD reintroduction are essential. Here, we propose an approach based on spatio-temporal scan statistics that the assesses risk of AD reintroduction in a disease-free territory by analysing the two most frequent risk pathways: movement of live domestic pigs and contact with wildlife reservoirs. The approach is illustrated using the case of Navarre, one of the first Spanish regions which plan to stop vaccination. Moreover, direct contacts among pig farms in Navarre were used to evaluate the potential spread of AD in the event of reintroduction. Areas at highest risk of AD reintroduction were in the southern part of the region during the second half of the year through pig movements and in the western and east-central parts of Navarre through contact with wild boars. Northern Navarre, despite having the highest density of pig farms, seems to be at low risk of AD reintroduction. Analysing the network of pig movements within Navarre revealed distinct northern and southern compartments that may be used in preventive compartmentalization strategies to reduce potential risk of AD re-infection in the scenario without vaccination. The approach described here may be extended to other regions and may be useful for guiding risk-based measures that reduce the risk of AD re-infection in a more cost-effective manner. Such analysis in Spain may allow authorities to stop vaccination in the safest possible way.