Publications by authors named "Pascal Hendrikx"

28 Publications

  • Page 1 of 1

Using a participatory qualitative risk assessment to estimate the risk of introduction and spread of transboundary animal diseases in scarce-data environments: A Spatial Qualitative Risk Analysis applied to foot-and-mouth disease in Tunisia 2014-2019.

Transbound Emerg Dis 2020 Nov 11. Epub 2020 Nov 11.

ASTRE, Univ Montpellier, CIRAD, INRAE, Montpellier, France.

This article presents a participative and iterative qualitative risk assessment framework that can be used to evaluate the spatial variation of the risk of infectious animal disease introduction and spread on a national scale. The framework was developed through regional training action workshops and field activities. The active involvement of national animal health services enabled the identification, collection and hierarchization of risk factors. Quantitative data were collected in the field, and expert knowledge was integrated to adjust the available data at regional level. Experts categorized and combined the risk factors into ordinal levels of risk per epidemiological unit to ease implementation of risk-based surveillance in the field. The framework was used to perform a qualitative assessment of the risk of introduction and spread of foot-and-mouth disease (FMD) in Tunisia as part of a series of workshops held between 2015 and 2018. The experts in attendance combined risk factors such as epidemiological status, transboundary movements, proximity to the borders and accessibility to assess the risk of FMD outbreaks in Tunisia. Out of the 2,075 Tunisian imadas, 23 were at a very high risk of FMD introduction, mainly at the borders; and 59 were at a very high risk of FMD spread. To validate the model, the results were compared to the FMD outbreaks notified by Tunisia during the 2014 FMD epizootic. Using a spatial Poisson model, a significant alignment between the very high and high-risk categories of spread and the occurrence of FMD outbreaks was shown. The relative risk of FMD occurrence was thus 3.2 higher for imadas in the very high and high spread risk categories than for imadas in the low and negligible spread risk categories. Our results show that the qualitative risk assessment framework can be a useful decision support tool for risk-based disease surveillance and control, in particular in scarce-data environments.
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http://dx.doi.org/10.1111/tbed.13920DOI Listing
November 2020

Resumeq: A Novel Way of Monitoring Equine Diseases Through the Centralization of Necropsy Data.

Front Vet Sci 2019 26;6:135. Epub 2019 Apr 26.

Coordination and Support Unit for Surveillance, ANSES, Lyon, France.

The French surveillance network for causes of equine mortality (Resumeq) was created in 2015 for the qualitative surveillance of equine mortality through the centralization in a national database of necropsy data and their subsequent epidemiological analysis. It was designed to identify the causes of equine mortality, monitor their evolution over time and space, and detect emerging diseases as early as possible. Resumeq is an event-based surveillance system involving various players and structures. It is organized around a steering body, a scientific and technical support committee and a coordination unit. Different tools have been developed specifically for Resumeq. These include standardized necropsy protocols, a thesaurus for the anatomopathological terms and the causes of equine death, and an interactive web application so that network contributors can display data analysis results. The four French veterinary schools, seventeen veterinary laboratories, and ten veterinary clinics already contribute to the production and centralization of standardized data. To date, the data from around 1,000 equine necropsies have been centralized. While most deaths were located in western France, the geographic coverage is gradually improving. Data analysis allows the main causes of death to be ranked and major threats identified on a local, regional or national level. Initial results demonstrate the feasibility and benefits of this national surveillance tool. Moreover, in the future, this surveillance could take an international dimension if several countries decided to jointly capitalize on their necropsy data.
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http://dx.doi.org/10.3389/fvets.2019.00135DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6524722PMC
April 2019

One Health Surveillance: A Matrix to Evaluate Multisectoral Collaboration.

Front Vet Sci 2019 24;6:109. Epub 2019 Apr 24.

French Agency for Food, Environmental and Occupational Health Safety (ANSES), UCAS, Lyon, France.

The international community and governmental organizations are actively calling for the implementation of One Health (OH) surveillance systems to target health hazards that involve humans, animals, and their environment. In our view, the main characteristic of a OH surveillance system is the collaboration across institutions and disciplines operating within the different sectors to plan, coordinate, and implement the surveillance process. However, the multisectoral organizational models and possible collaborative modalities implemented throughout the surveillance process are multi-fold and depend on the objective and context of the surveillance. The purpose of this study is to define a matrix to evaluate the quality and appropriateness of multisectoral collaboration through an in-depth analysis of its organization, implementation, and functions. We developed a first list of evaluation attributes based on (i) the characteristics of the organization, implementation, and functionality of multisectoral surveillance systems; and (ii) the existing attributes for the evaluation of health surveillance systems and OH initiatives. These attributes were submitted to two rounds of expert-opinion elicitation for review and validation. The final list of attributes consisted of 23 organizational attributes and 9 functional attributes, to which 3 organizational indexes were added measuring the overall organization of collaboration. We then defined 75 criteria to evaluate the level of satisfaction for the attributes and indexes. The criteria were scored following a four-tiered scoring grid. Graphical representations allowed for an easy overview of the evaluation results for both attributes and indexes. This evaluation matrix is the first to allow an in-depth analysis of collaboration in a multisectoral surveillance system and is the preliminary step toward the creation of a fully standalone tool for the evaluation of collaboration. After its practical application and adaptability to different contexts are field-tested, this tool could be very useful in identifying the strengths and weaknesses of collaboration occurring in a multisectoral surveillance system.
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http://dx.doi.org/10.3389/fvets.2019.00109DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6492491PMC
April 2019

Characteristics of One Health surveillance systems: A systematic literature review.

Prev Vet Med 2020 Aug 13;181:104560. Epub 2018 Oct 13.

ASTRE, Univ Montpellier, CIRAD, INRA, Montpellier, France; CIRAD, UMR ASTRE, 10900 Bangkok, Thailand; Kasetsart University, Faculty of Veterinary medicine, 50 Phaholyothin Rd., Ladyao, Jatujak, Bangkok, 10900 Thailand. Electronic address:

The concept of One Health (OH) promotes the decompartmentalisation of human, animal, and ecosystem health for the more efficient and sustainable governance of complex health issues. This means that traditional boundaries between disciplines and sectors must be transgressed and that all relevant stakeholders must be involved in the definition and management of health problems. International efforts have been made to strengthen collaboration across sectors and disciplines and OH surveillance is strongly encouraged at global, national and local-level to efficiently manage hazards involving humans, animals and ecosystems. This concept is intuitively appealing and would suggest the enhanced performance and cost-effectiveness of surveillance systems, as compared to more conventional approaches. Nevertheless, confusion and uncertainty regarding the practical application, outcomes and impacts prevail. We believe that this is due to the lack of a conceptual and methodological framework which would (i) define the characteristics of OH surveillance, and (ii) identify the appropriate mechanisms for inter-sectoral and multi-disciplinary collaboration, to ensure that the surveillance system performs well, with regard to the objective, the context and the health hazard under surveillance. The objective of the study is to define the organisational and functional characteristics of OH surveillance systems, the context in which they are implemented, as well as the influential factors which may obstruct or support their implementation and performance. To achieve this, a systematic literature review of existing OH surveillance systems was conducted using the Prisma guidelines. The selected systems were assessed according to 38 predetermined variables. These allowed the characterisation of their objectives, organisation, functioning, performance and benefits. Data extraction was conducted using a spreadsheet and a database was built using an electronic multiple-choice questionnaire. The literature search identified a total of 1635 records. After the screening phase, 31 references were kept and 22 additional references retrieved from bibliographies were added. From these 53 selected documents, we retrieved 41 different surveillance systems in line with the definition proposed in this study. The analysis of this database enabled the identification of different dimensions and areas of collaboration. Barriers and levers for the implementation of OH surveillance systems were also identified and discussed. Based on our results, we propose a framework to characterise the organisation of collaboration for the governance and operation of an effective OH surveillance system.
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http://dx.doi.org/10.1016/j.prevetmed.2018.10.005DOI Listing
August 2020

Infection of Wildlife by in France Assessment Through a National Surveillance System, Sylvatub.

Front Vet Sci 2018 30;5:262. Epub 2018 Oct 30.

Anses, Nancy Laboratory for Rabies and Wildlife, Malzéville, France.

infection was first described in free-ranging wildlife in France in 2001, with subsequent detection in hunter-harvested ungulates and badgers in areas where outbreaks of bovine tuberculosis (TB) were also detected in cattle. Increasing concerns regarding TB in wildlife led the French General Directorate for Food (DGAL) and the main institutions involved in animal health and wildlife management, to establish a national surveillance system for TB in free-ranging wildlife. This surveillance system is known as "Sylvatub." The system coordinates the activities of various national and local partners. The main goal of Sylvatub is to detect and monitor infection in wildlife through a combination of passive and active surveillance protocols adapted to the estimated risk level in each area of the country. Event-base surveillance relies on identification (molecular detection) () in gross lesions detected in hunter-harvested ungulates, () in ungulates that are found dead or dying, and () in road-killed badgers. Additional targeted surveillance in badgers, wild boars and red deer is implemented on samples from trapped or hunted animals in at-risk areas. With the exception of one unexplained case in a wild boar, infection in free-living wildlife has always been detected in the vicinity of cattle TB outbreaks with the same genotype of the infectious strains. Since 2012, was actively monitored in these infected areas and detected mainly in badgers and wild boars with apparent infection rates of 4.57-5.14% and 2.37-3.04%, respectively depending of the diagnostic test used (culture or PCR), the period and according to areas. Sporadic infection has also been detected in red deer and roe deer. This surveillance has demonstrated that infection, in different areas of France, involves a multi-host system including cattle and wildlife. However, infection rates are lower than those observed in badgers in the United Kingdom or in wild boars in Spain.
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http://dx.doi.org/10.3389/fvets.2018.00262DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6220493PMC
October 2018

Inferring pathogen dynamics from temporal count data: the emergence of Xylella fastidiosa in France is probably not recent.

New Phytol 2018 07 24;219(2):824-836. Epub 2018 Apr 24.

BIOGER, INRA, 78850, Thiverval-Grignon, France.

Unravelling the ecological structure of emerging plant pathogens persisting in multi-host systems is challenging. In such systems, observations are often heterogeneous with respect to time, space and host species, and may lead to biases of perception. The biased perception of pathogen ecology may be exacerbated by hidden fractions of the whole host population, which may act as infection reservoirs. We designed a mechanistic-statistical approach to help understand the ecology of emerging pathogens by filtering out some biases of perception. This approach, based on SIR (Susceptible-Infected-Removed) models and a Bayesian framework, disentangles epidemiological and observational processes underlying temporal counting data. We applied our approach to French surveillance data on Xylella fastidiosa, a multi-host pathogenic bacterium recently discovered in Corsica, France. A model selection led to two diverging scenarios: one scenario without a hidden compartment and an introduction around 2001, and the other with a hidden compartment and an introduction around 1985. Thus, Xylella fastidiosa was probably introduced into Corsica much earlier than its discovery, and its control could be arduous under the hidden compartment scenario. From a methodological perspective, our approach provides insights into the dynamics of emerging plant pathogens and, in particular, the potential existence of infection reservoirs.
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http://dx.doi.org/10.1111/nph.15177DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6032966PMC
July 2018

Perceptions and acceptability of some stakeholders about the bovine tuberculosis surveillance system for wildlife (Sylvatub) in France.

PLoS One 2018 15;13(3):e0194447. Epub 2018 Mar 15.

USC EPIMAI Unit, Anses, Ecole Nationale Vétérinaire d'Alfort, Maisons-Alfort, France.

Bovine tuberculosis (bTB) is a common disease of cattle and wildlife, with economic repercussions and implications for animal and human health. The surveillance of bTB in wildlife is particularly important, to shed light on the epidemiological role of wild species and for the adaptation of control measures. In France, a bTB surveillance system for free-ranging wildlife, the Sylvatub system, was launched in 2011 on wild boars, red deer, roe deer and badgers. It relies on active and passive surveillance activities, constrained by practical difficulties, such as the accessibility of wild animals, and regulatory rules for the trapping of badgers, for example. We report here the first assessment of stakeholders' perceptions of the Sylvatub system and its acceptability, based on 20 individual semi-structured interviews with three types of stakeholder (collectors, coordinators, officers) in areas with different rates of bTB infection. With the caveat that these findings cannot be assumed to be representative of the national situation, we found that the Sylvatub system was considered useful by all the stakeholders interviewed. Those from the world of hunting participate in surveillance mostly to help livestock farmers, who are not systematically involved in bTB surveillance in wildlife. Many practical and regulatory constraints were raised, which could be offset by recognition of the work done by the "hunting community", to maintain the willingness of these individuals to participate. We also identified a need for improvements in communication and information. Qualitative information, such as that collected here, is essential to improve our understanding of the reasons favoring and disfavoring participation in surveillance, and should be taken into account in the evaluation process. These results are relevant to hunters and to veterinary authorities wishing to identify the determinants of participation in the Sylvatub system. They could provide support for decision-making processes to improve surveillance strategies.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0194447PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5854387PMC
July 2018

Cost-effectiveness evaluation of bovine tuberculosis surveillance in wildlife in France (Sylvatub system) using scenario trees.

PLoS One 2017 11;12(8):e0183126. Epub 2017 Aug 11.

Ecole vétérinaire d'Alfort (Alfort National Veterinary School), Research unit EpiMAI USC Anses (Epidemiology of Animal Infectious Disease), Université Paris Est, Maisons-Alfort, France.

Bovine tuberculosis (bTB) is a common disease in cattle and wildlife, with health, zoonotic and economic implications. Infected wild animals, and particularly reservoirs, could hinder eradication of bTB from cattle populations, which could have an important impact on international cattle trade. Therefore, surveillance of bTB in wildlife is of particular importance to better understand the epidemiological role of wild species and to adapt the control measures. In France, a bTB surveillance system for free-ranging wildlife, the Sylvatub system, has been implemented since 2011. It relies on three surveillance components (SSCs) (passive surveillance on hunted animals (EC-SSC), passive surveillance on dead or dying animals (SAGIR-SSC) and active surveillance (PSURV-SSC)). The effectiveness of the Sylvatub system was previously assessed, through the estimation of its sensitivity (i.e. the probability of detecting at least one case of bTB infection by each SSC, specie and risk-level area). However, to globally assess the performance of a surveillance system, the measure of its sensitivity is not sufficient, as other factors such as economic or socio-economic factors could influence the effectiveness. We report here an estimation of the costs of the surveillance activities of the Sylvatub system, and of the cost-effectiveness of each surveillance component, by specie and risk-level, based on scenario tree modelling with the same tree structure as used for the sensitivity evaluation. The cost-effectiveness of the Sylvatub surveillance is better in higher-risk departments, due in particular to the higher probability of detecting the infection (sensitivity). Moreover, EC-SSC, which has the highest unit cost, is more efficient than the surveillance enhanced by the SAGIR-SSC, due to its better sensitivity. The calculation of the cost-effectiveness ratio shows that PSURV-SSC remains the most cost-effective surveillance component of the Sylvatub system, despite its high cost in terms of coordination, sample collection and laboratory analysis.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0183126PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5553909PMC
October 2017

A pan-European epidemiological study reveals honey bee colony survival depends on beekeeper education and disease control.

PLoS One 2017 9;12(3):e0172591. Epub 2017 Mar 9.

Unit of coordination and support to surveillance, ANSES, Scientific Affairs Department for Laboratories, Maisons-Alfort, France.

Reports of honey bee population decline has spurred many national efforts to understand the extent of the problem and to identify causative or associated factors. However, our collective understanding of the factors has been hampered by a lack of joined up trans-national effort. Moreover, the impacts of beekeeper knowledge and beekeeping management practices have often been overlooked, despite honey bees being a managed pollinator. Here, we established a standardised active monitoring network for 5 798 apiaries over two consecutive years to quantify honey bee colony mortality across 17 European countries. Our data demonstrate that overwinter losses ranged between 2% and 32%, and that high summer losses were likely to follow high winter losses. Multivariate Poisson regression models revealed that hobbyist beekeepers with small apiaries and little experience in beekeeping had double the winter mortality rate when compared to professional beekeepers. Furthermore, honey bees kept by professional beekeepers never showed signs of disease, unlike apiaries from hobbyist beekeepers that had symptoms of bacterial infection and heavy Varroa infestation. Our data highlight beekeeper background and apicultural practices as major drivers of honey bee colony losses. The benefits of conducting trans-national monitoring schemes and improving beekeeper training are discussed.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0172591PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5344352PMC
August 2017

The Added-Value of Using Participatory Approaches to Assess the Acceptability of Surveillance Systems: The Case of Bovine Tuberculosis in Belgium.

PLoS One 2016 27;11(7):e0159041. Epub 2016 Jul 27.

Research Unit of Epidemiology and Risk Analysis applied to Veterinary Sciences (UREAR-ULg),Fundamental and Applied Research for Animal and Health (FARAH), Faculty of Veterinary Medicine, University of Liege (ULg), Liège, Belgium.

Context And Objective: Bovine tuberculosis (bTB) surveillance in Belgium is essential to maintain the officially free status and to preserve animal and public health. An evaluation of the system is thus needed to ascertain the surveillance provides a precise description of the current situation in the country. The evaluation should assess stakeholders' perceptions and expectations about the system due to the fact that the acceptability has an influence on the levels of sensitivity and timeliness of the surveillance system. The objective of the study was to assess the acceptability of the bTB surveillance in Belgium, using participatory tools and the OASIS flash tool ('analysis tool for surveillance systems').

Methods: For the participatory process, focus group discussions and individual interviews were implemented with representatives involved with the system, both from cattle and wildlife part of the surveillance. Three main tools were used: (i) relational diagrams associated with smileys, (ii) flow diagrams associated with proportional piling, and (iii) impact diagrams associated with proportional piling. A total of six criteria were assessed, among which five were scored on a scale from -1 to +1. For the OASIS flash tool, one full day meeting with representatives from stakeholders involved with the surveillance was organised. A total of 19 criteria linked to acceptability were scored on a scale from 0 to 3.

Results And Conclusion: Both methods highlighted a medium acceptability of the bTB surveillance. The main elements having a negative influence were the consequences of official notification of a bTB suspect case in a farm, the low remuneration paid to private veterinarians for execution of intradermal tuberculin tests and the practical difficulties about the containment of the animals. Based on the two evaluation processes, relevant recommendations to improve the surveillance were made. Based on the comparison between the two evaluation processes, the added value of the participatory approach was highlighted.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0159041PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4962975PMC
July 2017

Assessment of fallen equine data in France and their usefulness for epidemiological investigations.

Res Vet Sci 2016 Feb 9;104:96-9. Epub 2015 Dec 9.

Epidemiology Unit, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), 31, avenue Tony Garnier, F69364 Lyon Cedex 07, France. Electronic address:

Quantitative information about equine mortality is relatively scarce, yet it could be of great value for epidemiology purposes. Several European projects based on the exploitation of data from rendering plants have been developed to improve livestock surveillance. Similar data are available for equines in France but have never been studied to date. The objective of this research was to evaluate the potential of the French Ministry of Agriculture's Fallen Stock Data Interchange (FSDI) database to provide quantitative mortality information on the French equine population. The quality of FSDI equine data from 2011 to 2014 was assessed using complementary data registered in the French equine census database, SIRE. Despite a perfectible quality, the FSDI database proved to be a valuable source for studying the basal patterns of mortality over time in the French equine population as illustrated by the spatial representation of the number of deaths. However, improvements in the FSDI database are needed, in particular regarding the registration of animal identification numbers, in order to detail equine mortality for epidemiology purposes.
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http://dx.doi.org/10.1016/j.rvsc.2015.12.005DOI Listing
February 2016

Vector-borne disease surveillance in livestock populations: A critical review of literature recommendations and implemented surveillance (BTV-8) in five European countries.

Prev Vet Med 2016 Mar 7;125:1-9. Epub 2016 Jan 7.

Swedish Zoonosis Centre, Department of Epidemiology and Disease Control, National Veterinary Institute (SVA), Uppsala, Sweden. Electronic address:

Preparedness against vector-borne threats depends on the existence of a long-term, sustainable surveillance of vector-borne disease and their relevant vectors. This work reviewed the availability of such surveillance systems in five European countries (Denmark, France, The Netherlands, Sweden and United Kingdom, part of the CoVetLab network). A qualitative assessment was then performed focusing on surveillance directed particularly to BTV-8. Information regarding surveillance activities were reviewed for the years 2008 and 2012. The results were then complemented with a critical scoping review of the literature aimed at identifying disease surveillance strategies and methods that are currently suggested as best suited to target vector-borne diseases in order to guide future development of surveillance in the countries in question. Passive surveillance was found to be efficient for early detection of diseases during the early phase of introduction into a free country. However, its value diminished once the disease has been established in a territory. Detection of emerging diseases was found to be very context and area specific, and thus active surveillance designs need to take the available epidemiological, ecological and entomological information into account. This was demonstrated by the effectiveness of the bulk milk surveillance in detecting the first case in Sweden, highlighting the need for output based standards to allow the most effective, context dependent, surveillance strategies to be used. Preparedness was of fundamental importance in determining the timeliness of detection and control in each country and that this in turn was heavily influenced by knowledge of emerging diseases in neighboring countries. Therefore it is crucial to share information on outbreaks between researchers and decision-makers and across borders continuously in order to react timely in case of an outbreak. Furthermore, timely reaction to an outbreak was heavily influenced by availability of control measures (vaccines), which is also strengthened if knowledge is shared quickly between countries. The assessment of the bluetongue surveillance in the affected countries showed that the degree of voluntary engagement varied, and that it is important to engage the public by general awareness and dissemination of results. The degree of engagement will also aid in establishing a passive surveillance system.
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http://dx.doi.org/10.1016/j.prevetmed.2016.01.005DOI Listing
March 2016

Simulation-Based Evaluation of the Performances of an Algorithm for Detecting Abnormal Disease-Related Features in Cattle Mortality Records.

PLoS One 2015 4;10(11):e0141273. Epub 2015 Nov 4.

Unité Epidémiologie, Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail-Laboratoire de Lyon, Lyon, France.

We performed a simulation study to evaluate the performances of an anomaly detection algorithm considered in the frame of an automated surveillance system of cattle mortality. The method consisted in a combination of temporal regression and spatial cluster detection which allows identifying, for a given week, clusters of spatial units showing an excess of deaths in comparison with their own historical fluctuations. First, we simulated 1,000 outbreaks of a disease causing extra deaths in the French cattle population (about 200,000 herds and 20 million cattle) according to a model mimicking the spreading patterns of an infectious disease and injected these disease-related extra deaths in an authentic mortality dataset, spanning from January 2005 to January 2010. Second, we applied our algorithm on each of the 1,000 semi-synthetic datasets to identify clusters of spatial units showing an excess of deaths considering their own historical fluctuations. Third, we verified if the clusters identified by the algorithm did contain simulated extra deaths in order to evaluate the ability of the algorithm to identify unusual mortality clusters caused by an outbreak. Among the 1,000 simulations, the median duration of simulated outbreaks was 8 weeks, with a median number of 5,627 simulated deaths and 441 infected herds. Within the 12-week trial period, 73% of the simulated outbreaks were detected, with a median timeliness of 1 week, and a mean of 1.4 weeks. The proportion of outbreak weeks flagged by an alarm was 61% (i.e. sensitivity) whereas one in three alarms was a true alarm (i.e. positive predictive value). The performances of the detection algorithm were evaluated for alternative combination of epidemiologic parameters. The results of our study confirmed that in certain conditions automated algorithms could help identifying abnormal cattle mortality increases possibly related to unidentified health events.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0141273PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4633029PMC
June 2016

Sensitivity of Bovine Tuberculosis Surveillance in Wildlife in France: A Scenario Tree Approach.

PLoS One 2015 30;10(10):e0141884. Epub 2015 Oct 30.

Unit UCAS, French Agency for Food, Environmental and Occupational Health and Safety (Anses), Maisons-Alfort, France.

Bovine tuberculosis (bTB) is a common disease in cattle and wildlife, with an impact on animal and human health, and economic implications. Infected wild animals have been detected in some European countries, and bTB reservoirs in wildlife have been identified, potentially hindering the eradication of bTB from cattle populations. However, the surveillance of bTB in wildlife involves several practical difficulties and is not currently covered by EU legislation. We report here the first assessment of the sensitivity of the bTB surveillance system for free-ranging wildlife launched in France in 2011 (the Sylvatub system), based on scenario tree modelling. Three surveillance system components were identified: (i) passive scanning surveillance for hunted wild boar, red deer and roe deer, based on carcass examination, (ii) passive surveillance on animals found dead, moribund or with abnormal behaviour, for wild boar, red deer, roe deer and badger and (iii) active surveillance for wild boar and badger. The application of these three surveillance system components depends on the geographic risk of bTB infection in wildlife, which in turn depends on the prevalence of bTB in cattle. We estimated the effectiveness of the three components of the Sylvatub surveillance system quantitatively, for each species separately. Active surveillance and passive scanning surveillance by carcass examination were the approaches most likely to detect at least one infected animal in a population with a given design prevalence, regardless of the local risk level and species considered. The awareness of hunters, which depends on their training and the geographic risk, was found to affect surveillance sensitivity. The results obtained are relevant for hunters and veterinary authorities wishing to determine the actual efficacy of wildlife bTB surveillance as a function of geographic area and species, and could provide support for decision-making processes concerning the enhancement of surveillance strategies.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0141884PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4627846PMC
June 2016

Applying participatory approaches in the evaluation of surveillance systems: A pilot study on African swine fever surveillance in Corsica.

Prev Vet Med 2015 Dec 17;122(4):389-98. Epub 2015 Oct 17.

Centre de Coopération Internationale en Recherche Agronomique Pour le Développement (CIRAD), Département ES, UPR AGIRs, TA C22/E, Campus International de Baillarguet, 34398 Montpellier Cedex 5, France. Electronic address:

The implementation of regular and relevant evaluations of surveillance systems is critical in improving their effectiveness and their relevance whilst limiting their cost. The complex nature of these systems and the variable contexts in which they are implemented call for the development of flexible evaluation tools. Within this scope, participatory tools have been developed and implemented for the African swine fever (ASF) surveillance system in Corsica (France). The objectives of this pilot study were, firstly, to assess the applicability of participatory approaches within a developed environment involving various stakeholders and, secondly, to define and test methods developed to assess evaluation attributes. Two evaluation attributes were targeted: the acceptability of the surveillance system and its the non-monetary benefits. Individual semi-structured interviews and focus groups were implemented with representatives from every level of the system. Diagramming and scoring tools were used to assess the different elements that compose the definition of acceptability. A contingent valuation method, associated with proportional piling, was used to assess the non-monetary benefits, i.e., the value of sanitary information. Sixteen stakeholders were involved in the process, through 3 focus groups and 8 individual semi-structured interviews. Stakeholders were selected according to their role in the system and to their availability. Results highlighted a moderate acceptability of the system for farmers and hunters and a high acceptability for other representatives (e.g., private veterinarians, local laboratories). Out of the 5 farmers involved in assessing the non-monetary benefits, 3 were interested in sanitary information on ASF. The data collected via participatory approaches enable relevant recommendations to be made, based on the Corsican context, to improve the current surveillance system.
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http://dx.doi.org/10.1016/j.prevetmed.2015.10.001DOI Listing
December 2015

Surveillance systems evaluation: a systematic review of the existing approaches.

BMC Public Health 2015 May 1;15:448. Epub 2015 May 1.

Département ES, UPR AGIRs, Bureau 208, Bâtiment E TA C22/E, Centre de coopération internationale en recherche agronomique pour le développement (CIRAD), Campus international de Baillarguet, Montpellier Cedex 5, 34398, France.

Background: Regular and relevant evaluations of surveillance systems are essential to improve their performance and cost-effectiveness. With this in mind several organizations have developed evaluation approaches to facilitate the design and implementation of these evaluations.

Methods: In order to identify and to compare the advantages and limitations of these approaches, we implemented a systematic review using the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses).

Results: After applying exclusion criteria and identifying other additional documents via citations, 15 documents were retained. These were analysed to assess the field (public or animal health) and the type of surveillance systems targeted; the development process; the objectives; the evaluation process and its outputs; and the attributes covered. Most of the approaches identified were general and provided broad recommendations for evaluation. Several common steps in the evaluation process were identified: (i) defining the surveillance system under evaluation, (ii) designing the evaluation process, (iii) implementing the evaluation, and (iv) drawing conclusions and recommendations.

Conclusions: A lack of information regarding the identification and selection of methods and tools to assess the evaluation attributes was highlighted; as well as a lack of consideration of economic attributes and sociological aspects.
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http://dx.doi.org/10.1186/s12889-015-1791-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4418053PMC
May 2015

Quantitative and qualitative assessment of the bovine abortion surveillance system in France.

Prev Vet Med 2015 Jun 25;120(1):62-9. Epub 2015 Feb 25.

ANSES-Lyon, Unité Epidémiologie, 31 avenue Tony Garnier, 69364 Lyon Cedex 07, France.

Bovine abortion is the main clinical sign of bovine brucellosis, a disease of which France has been declared officially free since 2005. To ensure the early detection of any brucellosis outbreak, event-driven surveillance relies on the mandatory notification of bovine abortions and the brucellosis testing of aborting cows. However, the under-reporting of abortions appears frequent. Our objectives were to assess the aptitude of the bovine abortion surveillance system to detect each and every bovine abortion and to identify factors influencing the system's effectiveness. We evaluated five attributes defined by the U.S. Centers for Disease Control with a method suited to each attribute: (1) data quality was studied quantitatively and qualitatively, as this factor considerably influences data analysis and results; (2) sensitivity and representativeness were estimated using a unilist capture-recapture approach to quantify the surveillance system's effectiveness; (3) acceptability and simplicity were studied through qualitative interviews of actors in the field, given that the surveillance system relies heavily on abortion notifications by farmers and veterinarians. Our analysis showed that (1) data quality was generally satisfactory even though some errors might be due to actors' lack of awareness of the need to collect accurate data; (2) from 2006 to 2011, the mean annual sensitivity - i.e. the proportion of farmers who reported at least one abortion out of all those who detected such events - was around 34%, but was significantly higher in dairy than beef cattle herds (highlighting a lack of representativeness); (3) overall, the system's low sensitivity was related to its low acceptability and lack of simplicity. This study showed that, in contrast to policy-makers, most farmers and veterinarians perceived the risk of a brucellosis outbreak as negligible. They did not consider sporadic abortions as a suspected case of brucellosis and usually reported abortions only to identify their cause rather than to reject brucellosis. The system proved too complex, especially for beef cattle farmers, as they may fail to detect aborting cows at pasture or have difficulties catching them for sampling. By investigating critical attributes, our evaluation highlighted the surveillance system's strengths and needed improvements. We believe our comprehensive approach can be used to assess other event-driven surveillance systems. In addition, some of our recommendations on increasing the effectiveness of event-driven brucellosis surveillance may be useful in improving the notification rate for suspected cases of other exotic diseases.
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http://dx.doi.org/10.1016/j.prevetmed.2015.02.019DOI Listing
June 2015

Spread and impact of the Schmallenberg virus epidemic in France in 2012-2013.

BMC Vet Res 2014 Oct 14;10:248. Epub 2014 Oct 14.

Epidemiological Surveillance Unit, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Maisons-Alfort, France.

Background: The Schmallenberg virus (SBV) emerged in Europe in 2011 and caused a widespread epidemic in ruminants.In France, SBV emergence was monitored through a national multi-stakeholder surveillance and investigation system. Based on the monitoring data collected from January 2012 to August 2013, we describe the spread of SBV in France during two seasons of dissemination (vector seasons 2011 and 2012) and we provide a large-scale assessment of the impact of this new disease in ruminants.

Results: SBV impact in infected herds was primarily due to the birth of stillborns or deformed foetuses and neonates. Congenital SBV morbidity level was on average moderate, although higher in sheep than in other ruminant species. On average, 8% of lambs, 3% of calves and 2% of kids born in SBV-infected herds showed typical congenital SBV deformities. In addition, in infected herds, farmers reported retrospectively a lower prolificacy during the vector season, suggesting a potential impact of acute SBV infection during mating and early stages of gestation.

Conclusions: Due to the lack of available control and prevention measures, SBV spread quickly in the naive ruminant population. France continues to monitor for SBV, and updated information is made available online on a regular basis [http://www.plateforme-esa.fr/]. Outbreaks of congenital SBV are expected to occur sporadically from now on, but further epidemics may also occur if immunity at population level declines.
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http://dx.doi.org/10.1186/s12917-014-0248-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4210488PMC
October 2014

Why do farmers and veterinarians not report all bovine abortions, as requested by the clinical brucellosis surveillance system in France?

BMC Vet Res 2014 Apr 24;10:93. Epub 2014 Apr 24.

Anses-Lyon, Unité Epidémiologie, 31 avenue Tony Garnier, 69364 Lyon Cedex 07, France.

Background: Since 2005, France has been officially free of brucellosis, an infectious disease that causes abortion in cattle and can be transmitted from cattle to humans. Recent animal and human cases have drawn attention to the need to prevent infection of humans and animals from any primary outbreaks. In order to detect any new outbreaks as soon as possible, a clinical surveillance system requires farmers and veterinarians to report each abortion and to test the aborting cow for brucellosis. However, under-reporting limits the sensitivity of this system. Our objective was to identify the barriers and motivations influencing field actors in their decision to report or not to report bovine abortions. We used a qualitative approach with semi-structured interviews of 12 cattle farmers and their eight veterinarians.

Results: Our analysis showed that four main themes influence the decision-making process of farmers and veterinarians: 1) the perceived risk of brucellosis and other abortive diseases; 2) the definition of a suspected case of brucellosis and other abortive diseases adopted by field actors, which is less sensitive than the mandatory definition; 3) the cost-benefit analysis conducted by actors, taking into account regulatory and health aspects, economic and financial losses, technical and practical factors; 4) the level of cooperation within the socio-technical network. We discussed how early detection may be improved by revising the definition of abortion, extending the time frame for notification and generalising the differential diagnosis of the causes of abortion.

Conclusions: In contrast to quantitative approaches, qualitative studies can identify the factors (including unknown factors) influencing the decision-making process of field actors and reveal why they take those factors into consideration. Our qualitative study sheds light on the factors underlying the poor sensitivity of clinical brucellosis surveillance system for cattle in France, and suggests that early detection may be improved by considering actors' perceptions. We believe our findings may provide further insight into ways of improving other clinical surveillance systems and thus reduce the risk of disease.
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http://dx.doi.org/10.1186/1746-6148-10-93DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4036594PMC
April 2014

Demographics of the European apicultural industry.

PLoS One 2013 13;8(11):e79018. Epub 2013 Nov 13.

Honeybee Pathology Unit, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), European Union and National Reference Laboratory for honeybee health, Sophia Antipolis, France ; Epidemiological Surveillance Unit, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Scientific Affairs Department for Laboratories, Maisons-Alfort, France.

Over the last few years, many European and North American countries have reported a high rate of disorders (mortality, dwindling and disappearance) affecting honeybee colonies (Apis mellifera). Although beekeeping has become an increasingly professional activity in recent years, the beekeeping industry remains poorly documented in Europe. The European Union Reference Laboratory for Honeybee Health sent a detailed questionnaire to each Member State, in addition to Kosovo and Norway, to determine the demographics and state of their beekeeping industries. Based on data supplied by the National Reference Laboratory for honeybee diseases in each European country, a European database was created to describe the beekeeping industry including the number and types of beekeepers, operation size, industry production, and health (notifiable diseases, mortalities). The total number of beekeepers in Europe was estimated at 620,000. European honey production was evaluated at around 220,000 tons in 2010. The price of honey varied from 1.5 to 40 €/kg depending on the country and on the distribution network. The estimated colony winter mortality varied from 7 to 28% depending on the country and the origin of the data (institutional survey or beekeeping associations). This survey documents the high heterogeneity of the apicultural industry within the European Union. The high proportion of non-professional beekeepers and the small mean number of colonies per beekeeper were the only common characteristics at European level. The tremendous variation in European apicultural industries has implication for any comprehensive epidemiological or economic analysis of the industry. This variability needs to be taken into account for such analysis as well as for future policy development. The industry would be served if beekeeping registration was uniformly implemented across member states. Better information on the package bee and queen production would help in understanding the ability of the industry to replace lost honey bee stocks.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0079018PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3827320PMC
September 2014

Inventory of veterinary syndromic surveillance initiatives in Europe (Triple-S project): current situation and perspectives.

Prev Vet Med 2013 Sep 5;111(3-4):220-9. Epub 2013 Jul 5.

Unité Epidémiologie, Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (Anses), 31, avenue Tony Garnier, F69364 Lyon Cedex 07, France.

Within the current context that favours the emergence of new diseases, syndromic surveillance (SyS) appears increasingly more relevant tool for the early detection of unexpected health events. The Triple-S project (Syndromic Surveillance Systems in Europe), co-financed by the European Commission, was launched in September 2010 for a three year period to promote both human and animal health SyS in European countries. Objectives of the project included performing an inventory of current and planned European animal health SyS systems and promoting knowledge transfer between SyS experts. This study presents and discusses the results of the Triple-S inventory of European veterinary SyS initiatives. European SyS systems were identified through an active process based on a questionnaire sent to animal health experts involved in SyS in Europe. Results were analyzed through a descriptive analysis and a multiple factor analysis (MFA) in order to establish a typology of the European SyS initiatives. Twenty seven European SyS systems were identified from twelve countries, at different levels of development, from project phase to active systems. Results of this inventory showed a real interest of European countries for SyS but also highlighted the novelty of this field. This survey highlighted the diversity of SyS systems in Europe in terms of objectives, population targeted, data providers, indicators monitored. For most SyS initiatives, statistical analysis of surveillance results was identified as a limitation in using the data. MFA results distinguished two types of systems. The first one belonged to the private sector, focused on companion animals and had reached a higher degree of achievement. The second one was based on mandatory collected data, targeted livestock species and is still in an early project phase. The exchange of knowledge between human and animal health sectors was considered useful to enhance SyS. In the same way that SyS is complementary to traditional surveillance, synergies between human and animal health SyS could be an added value, most notably to enhance timeliness, sensitivity and help interpreting non-specific signals.
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http://dx.doi.org/10.1016/j.prevetmed.2013.06.005DOI Listing
September 2013

Assessing the mandatory bovine abortion notification system in France using unilist capture-recapture approach.

PLoS One 2013 14;8(5):e63246. Epub 2013 May 14.

Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (Anses), Unité Epidémiologie du Laboratoire de Lyon, Lyon, France.

The mandatory bovine abortion notification system in France aims to detect as soon as possible any resurgence of bovine brucellosis. However, under-reporting seems to be a major limitation of this system. We used a unilist capture-recapture approach to assess the sensitivity, i.e. the proportion of farmers who reported at least one abortion among those who detected such events, and representativeness of the system during 2006-2011. We implemented a zero-inflated Poisson model to estimate the proportion of farmers who detected at least one abortion, and among them, the proportion of farmers not reporting. We also applied a hurdle model to evaluate the effect of factors influencing the notification process. We found that the overall surveillance sensitivity was about 34%, and was higher in beef than dairy cattle farms. The observed increase in the proportion of notifying farmers from 2007 to 2009 resulted from an increase in the surveillance sensitivity in 2007/2008 and an increase in the proportion of farmers who detected at least one abortion in 2008/2009. These patterns suggest a raise in farmers' awareness in 2007/2008 when the Bluetongue Virus (BTV) was detected in France, followed by an increase in the number of abortions in 2008/2009 as BTV spread across the country. Our study indicated a lack of sensitivity of the mandatory bovine abortion notification system, raising concerns about the ability to detect brucellosis outbreaks early. With the increasing need to survey the zoonotic Rift Valley Fever and Q fever diseases that may also cause bovine abortions, our approach is of primary interest for animal health stakeholders to develop information programs to increase abortion notifications. Our framework combining hurdle and ZIP models may also be applied to estimate the completeness of other clinical surveillance systems.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0063246PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3653928PMC
December 2013

Epidemiology, molecular virology and diagnostics of Schmallenberg virus, an emerging orthobunyavirus in Europe.

Vet Res 2013 May 15;44:31. Epub 2013 May 15.

ANSES-INRA-ENVA, UMR 1161 Virologie, 23 avenue du Général De Gaulle, Maisons-Alfort 94704, France.

After the unexpected emergence of Bluetongue virus serotype 8 (BTV-8) in northern Europe in 2006, another arbovirus, Schmallenberg virus (SBV), emerged in Europe in 2011 causing a new economically important disease in ruminants. The virus, belonging to the Orthobunyavirus genus in the Bunyaviridae family, was first detected in Germany, in The Netherlands and in Belgium in 2011 and soon after in the United Kingdom, France, Italy, Luxembourg, Spain, Denmark and Switzerland. This review describes the current knowledge on the emergence, epidemiology, clinical signs, molecular virology and diagnosis of SBV infection.
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http://dx.doi.org/10.1186/1297-9716-44-31DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3663787PMC
May 2013

Defining syndromes using cattle meat inspection data for syndromic surveillance purposes: a statistical approach with the 2005-2010 data from ten French slaughterhouses.

BMC Vet Res 2013 Apr 30;9:88. Epub 2013 Apr 30.

Unité Epidémiologie, Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (Anses), 31 avenue Tony Garnier, F69364, Lyon, Cedex 07, France.

Background: The slaughterhouse is a central processing point for food animals and thus a source of both demographic data (age, breed, sex) and health-related data (reason for condemnation and condemned portions) that are not available through other sources. Using these data for syndromic surveillance is therefore tempting. However many possible reasons for condemnation and condemned portions exist, making the definition of relevant syndromes challenging.The objective of this study was to determine a typology of cattle with at least one portion of the carcass condemned in order to define syndromes. Multiple factor analysis (MFA) in combination with clustering methods was performed using both health-related data and demographic data.

Results: Analyses were performed on 381,186 cattle with at least one portion of the carcass condemned among the 1,937,917 cattle slaughtered in ten French abattoirs. Results of the MFA and clustering methods led to 12 clusters considered as stable according to year of slaughter and slaughterhouse. One cluster was specific to a disease of public health importance (cysticercosis). Two clusters were linked to the slaughtering process (fecal contamination of heart or lungs and deterioration lesions). Two clusters respectively characterized by chronic liver lesions and chronic peritonitis could be linked to diseases of economic importance to farmers. Three clusters could be linked respectively to reticulo-pericarditis, fatty liver syndrome and farmer's lung syndrome, which are related to both diseases of economic importance to farmers and herd management issues. Three clusters respectively characterized by arthritis, myopathy and Dark Firm Dry (DFD) meat could notably be linked to animal welfare issues. Finally, one cluster, characterized by bronchopneumonia, could be linked to both animal health and herd management issues.

Conclusion: The statistical approach of combining multiple factor analysis with cluster analysis showed its relevance for the detection of syndromes using available large and complex slaughterhouse data. The advantages of this statistical approach are to i) define groups of reasons for condemnation based on meat inspection data, ii) help grouping reasons for condemnation among a list of various possible reasons for condemnation for which a consensus among experts could be difficult to reach, iii) assign each animal to a single syndrome which allows the detection of changes in trends of syndromes to detect unusual patterns in known diseases and emergence of new diseases.
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http://dx.doi.org/10.1186/1746-6148-9-88DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3681570PMC
April 2013

Assessment of the utility of routinely collected cattle census and disposal data for syndromic surveillance.

Prev Vet Med 2012 Jul 12;105(3):244-52. Epub 2012 Jan 12.

Unité Epidémiologie, Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (Anses), 31, avenue Tony Garnier, F69364 Lyon Cedex 07, France.

Census and disposal data provide a multipurpose source of information on cattle mortality. The retrospective analyses we conducted on the data gathered in the National Cattle Register produced relevant information for describing and modelling the cattle mortality baseline and evaluating the impact of the 2007-2008 Blue Tongue epidemic on the French cattle population. This work was conducted retrospectively but showed that monitoring cattle mortality near real time could help detecting unexpected events. We are thus currently working on a timely and automated system to monitor cadaver disposal requests received by rendering plants, thanks to a data interchange system recently implemented between the Ministry of Agriculture and the fallen stock companies. Besides technical and methodological challenges, using these data for surveillance purposes raises epidemiological questions that still need to be answered. The question remains notably as to whether an abnormal increased mortality is a sensitive and timely signal for detecting unexpected health events. It appears also very challenging to identify the most adequate surveillance scale (time, space and population) and the most adequate anomaly detection algorithms to apply when the characteristics of the signals to be detected (shape, amplitude, etc.) are not known a priori. In Human health, similar systems have not yet proven their ability to detect unexpected events earlier than classical surveillance systems currently in place, but they have already demonstrated their value for real time assessment of identified and potentially dangerous events. Combined with traditional surveillance systems, we think that monitoring routinely collected data could improve the surveillance of the animal population health. Even if not used for detection purposes, cattle mortality monitoring could be used to rapidly produce information on the impact and evolution of identified events, what would facilitate decision-making regarding management measures and improve the communication.
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http://dx.doi.org/10.1016/j.prevetmed.2011.12.015DOI Listing
July 2012

Using the National Cattle Register to estimate the excess mortality during an epidemic: application to an outbreak of Bluetongue serotype 8.

Epidemics 2010 Dec 15;2(4):207-14. Epub 2010 Oct 15.

Epidemiology Unit, French Agency for Food, Environmental and Occupational Health & Safety (Anses), 31, avenue Tony Garnier, F69364 Lyon Cedex 07, France.

National Cattle Registers have been widely used to examine animal movements and their role in disease transmission, but less frequently for other epidemiological applications. Our study shows how routinely collected identification data can be used to evaluate the population impact of an epidemic in cattle and to derive an indirect estimate of the associated mortality. We adapted a method developed by Human health agencies, based on the modelling of historical mortality fluctuations, to analyze the evolution of mortality in a cattle population subjected to a Bluetongue serotype 8 (BT8) outbreak. Between 01/07/2007 and 01/07/2008, 21,017 cattle died in the considered population whereas 16,691 deaths were expected according to the model. 43% of the 4326 extra deaths were found in calves less than 7 days of age, but excess mortality was found in each age group. The temporal distribution of extra-deaths, described at a weekly scale, suggests that they were related to the BT8 epidemic. The presented method could be an appreciable tool for estimating the global burden of epidemics since it is based on data already routinely collected in each European Member State. This study was conducted retrospectively but considering the promptness of the notification system, the method could be used to monitor the evolution of epidemics in near-real time.
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http://dx.doi.org/10.1016/j.epidem.2010.10.002DOI Listing
December 2010

Comparison between active and passive surveillance within the network of epidemiological surveillance of animal diseases in Chad.

Acta Trop 2010 Nov 22;116(2):147-51. Epub 2010 Jul 22.

Ministère de l'Elevage, Direction des Services vétérinaires, Service d'Epidémiologie, N'Djaména, Chad.

A comparative study between passive and active surveillance based on herd visits (villages) was conducted over a period of 24 months. It included 106 surveillance stations of the animal disease epidemiological surveillance network in Chad distributed randomly into 52 stations of active surveillance and 54 stations of passive surveillance. Nine diseases of various vaccination and expected prevalence status were monitored. The active surveillance stations carried out four herd visits monthly to look for the diseases under surveillance and organised four farmers awareness-raising meetings to stimulate them to make disease notifications. The passive surveillance stations held each month four farmer awareness-raising meetings. The suspicions recorded by the stations were consigned to a suspicion form specific to each disease, indicating whether a call from the farmer, a visit to the herd or a awareness-raising meeting was the source. The results showed that, irrespective of surveillance type, all diseases under surveillance, except the rare diseases (Rinderpest and Rift Valley Fever) were reported by the surveillance agents. However, suspicions recorded following farmer calls are significantly more important than suspicions carried out during herd visits or meetings. Nevertheless, a considerable number of suspicions is recorded during awareness-raising meetings. Finally approximately 83% of the herd visits realised by the active surveillance stations showed negative results (no suspicion identified). Passive surveillance stimulated by awareness-raising meetings appears to be better adapted to Chads conditions and less expensive for the surveillance of existing diseases. However, for the rare diseases, other methods of specific active surveillance (such as for example sentinel herds) remain important to complete passive surveillance.
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http://dx.doi.org/10.1016/j.actatropica.2010.07.004DOI Listing
November 2010

The Caribbean animal health network: new tools for harmonization and reinforcement of animal disease surveillance.

Ann N Y Acad Sci 2008 Dec;1149:12-5

Ministry of Agriculture, Belize.

The Caribbean Animal Health Network (CaribVET) is a collaboration of veterinary services, diagnostic laboratories, research institutes, universities, and regional/international organizations to improve animal health in the Caribbean. New tools were used by the network to develop regional animal health activities: (1) A steering committee, a coordination unit, and working groups on specific diseases or activities were established. The working group on avian influenza used a collaborative Web site to develop a regionally harmonized avian influenza surveillance protocol and performance indicators. (2) A specific network was implemented on West Nile virus (WNV) to describe the WNV status of the Caribbean countries, to perform a technology transfer of WNV diagnostics, and to establish a surveillance system. (3) The CaribVET Web site (http://www.caribvet.net) encompasses information on surveillance systems, diagnostic laboratories, conferences, bibliography, and diseases of major concern in the region. It is a participatory Web site allowing registered users to add or edit information, pages, or data. An online notification system of sanitary information was set up for Guadeloupe to improve knowledge on animal diseases and facilitate early alert.
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http://dx.doi.org/10.1196/annals.1428.055DOI Listing
December 2008