Le présent article a pour objectif de discuter de la faisabilité et de l’intérêt que représenterait le suivi d’un indicateur indirect de survenue des avortements élaboré à partir des données d’insémination artificielle, le taux d’avortements précoces, afin d’identifier l’impact d’un évènement abortif, de manière rétrospective ou prospective. Deux études sont présentées pour illustrer le propos, ayant eu pour objet d’estimer, par l’analyse des variations du taux d’avortements précoces, l’impact de l’épizootie de fièvre catarrhale ovine due au sérotype 8 (FCO-8), qui a émergé en France en 2006, puis s’est diffusée dans une large partie du territoire métropolitain en 2007 et 2008. La première étude souligne qu’une analyse des variations temporelles du taux d’avortements précoces à l’échelle du département a permis d’identifier a posteriori l’impact de la FCO-8 sur la survenue d’avortements en élevages de bovins. La seconde étude indique qu’une analyse prospective hebdomadaire des variations temporelles du taux d’avortements précoces aurait permis d’identifier l’impact de la FCO-8 dans un département dans un délai médian de 12 semaines suivant son introduction. Considérant ces résultats, il apparaît pertinent de réfléchir à la mise en place d’une surveillance intégrée des avortements en élevage de bovins, qui reposerait sur deux volets : la déclaration obligatoire des avortements (sous la forme du dispositif actuel en version révisée) et un outil de surveillance syndromique (qui devrait être mis en place à une échelle infra-départementale, en particulier pour améliorer les délais de détection).

In the winter 2016-2017 the largest epidemic of highly pathogenic avian influenza (HPAI) ever recorded in the European Union spread to all 28 member states. France was hit particularly hard and reported a total of 484 infected premises (IPs) by March 2017. We developed a mathematical model to analyze the spatiotemporal evolution of the epidemic and evaluate the impact of control strategies. We estimated that farms rearing ducks were on average 2.5 times more infectious and 5.0 times more susceptible to HPAI than farms rearing other avian species. The implementation of surveillance zones around IPs reduced transmission by a factor of 1.8 on average. Compared to the strengthening of pre-emptive culling measures enforced by French authorities in February 2017, we found that a faster depopulation of diagnosed IPs would have had a larger impact on the total number of infections. For example, halving the time delay from detection to slaughter of infected animals would have reduced the total number of IPs by 52% and total cull numbers by 50% on average. This study showcases the possible contribution of modeling to inform and optimize control strategies during an outbreak.

Q fever is a zoonotic abortive disease of ruminants mostly transmitted by inhalation of aerosols contaminated by Coxiella burnetii. Clusters of cases or even epidemics regularly occur in humans but, to date, there is no consensus about the best way to carry out outbreak investigations in order to identify potential farms at risk. Although environmental samples might be useful during such investigations, there are few baseline data on the presence of C. burnetii in the environment of ruminant farms. We thus investigated dust samples from cattle, sheep and goat farm buildings in order to (a) estimate C. burnetii detection frequency and bacterial loads in the environment, and (b) determine whether this environmental contamination is associated with series of abortions attributed to Q fever. We considered 113 herds with a recent abortive episode potentially related (n = 60) or not (n = 53) to C. burnetii. Dust was sampled using a swab cloth and tested by a quantitative PCR method targeting the IS1111 gene. Coxiella burnetii DNA was detected on 9 of 50 cattle farms, 13 of 19 goat farms and 30 of 40 sheep farms. On 16 cloths, bacterial loads were higher than 10(8) genome equivalents, levels as high as in infectious materials such as placentas and aborted foetuses. Overall, the probability of detecting C. burnetii DNA was higher on small ruminant farms than cattle farms, in herds suspected of Q fever and in large herds. We conclude that swab cloths are a putative indicator of contamination of ruminant farms by C. burnetii.

Highly pathogenic avian influenza A(H5N8) clade 2.3.4.4 spread in France during 2016-2017. We assessed the biosecurity and avian influenza virus infection status of 70 backyard flocks near H5N8-infected commercial farms. One flock was seropositive for clade 2.3.4.4. Backyard flocks linked to commercial farms had elevated risk for H5 infection.

Risk factors are key epidemiological concepts that are used to explain disease distributions. Identifying disease risk factors is generally done by comparing the characteristics of diseased and non-diseased populations. However, imperfect disease detectability generates disease observations that do not necessarily represent accurately the true disease situation. In this study, we conducted an extensive simulation exercise to emphasize the impact of imperfect disease detection on the outcomes of logistic models when case reports are aggregated at a larger scale (e.g., diseased animals aggregated at farm level). We used a probabilistic framework to simulate both the disease distribution in herds and imperfect detectability of the infected animals in these herds. These simulations show that, under logistic models, true herd-level risk factors are generally correctly identified but their associated odds ratio are heavily underestimated as soon as the sensitivity of the detection is less than one. If the detectability of infected animals is not only imperfect but also heterogeneous between herds, the variables associated with the detection heterogeneity are likely to be incorrectly identified as risk factors. This probability of type I error increases with increasing heterogeneity of the detectability, and with decreasing sensitivity. Finally, the simulations highlighted that, when count data is available (e.g., number of infected animals in herds), they should not be reduced to a presence/absence dataset at the herd level (e.g., presence or not of at least one infected animal) but rather modeled directly using zero-inflated count models which are shown to be much less sensitive to imperfect detectability issues. In light of these simulations, we revisited the analysis of the French bovine abortion surveillance data, which has already been shown to be characterized by imperfect and heterogeneous abortion detectability. As expected, we found substantial differences between the quantitative outputs of the logistic model and those of the zero-inflated Poisson model. We conclude by strongly recommending that efforts should be made to account for, or at the very least discuss, imperfect disease detectability when assessing associations between putative risk factors and observed disease distributions, and advocate the use of zero-inflated count models if count data is available.

Depuis 2014, de nombreux foyers de fievre catarrhale ovine (FCO) sont declares en Europe chaque annee, principalement de serotype 4, mais aussi de serotype 1 (Italie, Croatie, Espagne, Portugal) et de serotype 8 (France, Chypre, Suisse). On observe une diminution du nombre de foyers de FCO-1 depuis 2014, ainsi qu'une augmentation du nombre de foyers de FCO-4 et, depuis 2015, de FCO-8. L'annee 2017 a ete marquee par une importante epizootie de serotype 4 qui a frappe la Sardaigne et la Corse de fin juin a decembre 2017 et l'introduction de ce serotype 4 en France continentale. Le serotype 2 a ete identifie en Italie en 2014, le serotype 3 a ete detecte pour la premiere fois en Europe en Sicile en 2017, et le serotype 16 a ete signale a Chypre en 2014, puis en Grece et en Turquie a partir de septembre 2017. La situation epidemiologique de la FCO en Europe est donc complexe et le maintien d'un niveau de vigilance eleve est necessaire car le changement climatique, l'evolution des aires de distribution des insectes vecteurs et les mouvements d'animaux constituent des facteurs de risque d'introduction de nouveaux serotypes en Europe.

La fièvre Q est une maladie abortive des ruminants transmise par voie aérienne à partir de l’environnement contaminé par les produits d’avortements, de mises-bas et par les excréments. Néanmoins, la relation entre survenue d’avortements et contamination environnementale reste mal définie. Notre objectif était d’estimer la fréquence de détection et les charges de Coxiella burnetii dans la poussière des bâtiments d’élevage en relation avec l’occurrence d’épisodes abortifs attribués à la fièvre Q. Des échantillons de poussière (n= 109) ont été prélevés dans les élevages bovins, ovins et caprins, cliniquement atteints de fièvre Q ou non. L’ADN de C. burnetii a été détecté par PCR quantitative dans de nombreux échantillons. La probabilité de détection était plus grande dans les élevages caprins et ovins que dans les élevages bovins, et dans les élevages cliniquement atteints de fièvre Q que dans les élevages non cliniquement atteints. La poussière des bâtiments pourrait donc constituer un indicateur du statut des élevages pour la fièvre Q.

Introduction: France is one of Europe's foremost poultry producers and the world's fifth largest producer of poultry meat. In November 2016, highly pathogenic avian influenza (HPAI) virus subtype H5N8 emerged in poultry in the country. As of 23 March 2017, a total of 484 confirmed outbreaks were reported, with consequences on animal health and socio-economic impacts for producers. Methods: We examined the spatio-temporal distribution of outbreaks that occurred in France between November 2016 and March 2017, using the space-time K-function and space-time permutation model of the scan statistic test. Results: Most outbreaks affected duck flocks in south-west France. A significant space-time interaction of outbreaks was present at the beginning of the epidemic within a window of 8 km and 13 days. This interaction disappeared towards the epidemic end. Five spatio-temporal outbreak clusters were identified in the main poultry producing areas, moving sequentially from east to west. The average spread rate of the epidemic front wave was estimated to be 5.5 km/week. It increased from February 2017 and was negatively associated with the duck holding density. Conclusion: HPAI-H5N8 infections varied over time and space in France. Intense transmission events occurred at the early stages of the epidemic, followed by long-range jumps in the disease spread towards its end. Findings support strict control strategies in poultry production as well as the maintenance of high biosecurity standards for poultry holdings. Factors and mechanisms driving HPAI spread need to be further investigated.

After its introduction in Turkey in November 2013 and subsequent spread in this country, lumpy skin disease (LSD) was first reported in the western Turkey in May 2015. It was observed in cattle in Greece and reported to the World Organization for Animal Health (OIE) in August 2015. From May 2015 to August 2016, 1,092 outbreaks of lumpy skin disease were reported in cattle from western Turkey and eight Balkan countries: Greece, Bulgaria, The Former Yugoslav Republic of Macedonia, Serbia, Kosovo, and Albania. During this period, the median LSD spread rate was 7.3 km/week. The frequency of outbreaks was highly seasonal, with little or no transmission reported during the winter. Also, the skewed distribution of spread rates suggested two distinct underlying epidemiological processes, associating local and distant spread possibly related to vectors and cattle trade movements, respectively.

La dermatose nodulaire contagieuse bovine est une maladie virale enzootique en Afrique sub-saharienne. Apres avoir ete detectee pour la premiere fois en Turquie en novembre 2013, elle s'est ensuite etendue a l'Europe, tout d'abord a la partie europeenne de la Turquie en mai 2015, puis dans les Balkans. Cet article fait le point sur la situation epidemiologique de la maladie dans les Balkans et en Turquie au 30 novembre 2017. Il rapporte l'effet protecteur de la vaccination dans les pays qui ont beneficie d'une forte couverture vaccinale, precise les manifestations cliniques et les caracteristiques de la maladie dans les pays de l'UE infectes et rappelle la strategie de surveillance mise en place en France contre ce danger sanitaire de categorie 1.

Veterinary RecordVolume 180, Issue 1 p. 24-24 Letter Detection of Schmallenberg virus in France since 2012 Kristel Gache, Kristel Gache GDS France, Paris, FranceSearch for more papers by this authorAnne Touratier, Anne Touratier GDS France, Paris, FranceSearch for more papers by this authorLaure Bournez, Laure Bournez ANSES, Maisons-Alfort, FranceSearch for more papers by this authorStephan Zientara, Stephan Zientara ANSES, Maisons-Alfort, FranceSearch for more papers by this authorAnne Bronner, Anne Bronner Directorate General for Food, Paris, FranceSearch for more papers by this authorFrançoise Dion, Françoise Dion Races de France, Paris, FranceSearch for more papers by this authorEmmanuel Garin, Emmanuel Garin Coop de France, Paris, FranceSearch for more papers by this authorDidier Calavas, Didier Calavas ANSES, Laboratory of Lyon, Epidemiology Unit, Lyon, FranceSearch for more papers by this author Kristel Gache, Kristel Gache GDS France, Paris, FranceSearch for more papers by this authorAnne Touratier, Anne Touratier GDS France, Paris, FranceSearch for more papers by this authorLaure Bournez, Laure Bournez ANSES, Maisons-Alfort, FranceSearch for more papers by this authorStephan Zientara, Stephan Zientara ANSES, Maisons-Alfort, FranceSearch for more papers by this authorAnne Bronner, Anne Bronner Directorate General for Food, Paris, FranceSearch for more papers by this authorFrançoise Dion, Françoise Dion Races de France, Paris, FranceSearch for more papers by this authorEmmanuel Garin, Emmanuel Garin Coop de France, Paris, FranceSearch for more papers by this authorDidier Calavas, Didier Calavas ANSES, Laboratory of Lyon, Epidemiology Unit, Lyon, FranceSearch for more papers by this author First published: 07 January 2017 https://doi.org/10.1136/vr.j38Citations: 3Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume180, Issue1January 2017Pages 24-24 RelatedInformation

Multiple challenges have to be faced both for animal and public health in the fields of infectious abortion surveillance especially when zoonotic diseases are concerned: ensuring early detection of brucellosis, improving outbreak surveillance as well as animal health management. Thus, a global approach to diagnosis of abortive infectious diseases was discussed within the framework of the French platform for animal health surveillance by a collaborative multi-stakeholder group. Q fever appeared as a relevant target to initiate this new approach in order to test the different steps, from the implementation in the farms to the analysis of the results. Therefore, a pilot study was set up in 2012, for three years, in ten departements (administrative unit of 5500 Km2 on average) covering 1493 goat farms. It focused on abortive episodes defined as at least three abortions over seven days or less. A farm-level diagnosis approach, i.e. the interpretation of combinations of results from several animals was used. Therefore, the decision-making was based on the results of two qPCR applied on vaginal swabs (individual or pooled analysis) and, if necessary, on further serological analyses, taking account of the vaccination status of herds. The National Reference Laboratory had a key role as it was involved in validation and harmonization of the analytical process. A total of 114 abortive episodes from 105 goat farms were investigated. Among them, 16.7% were considered due to Q fever (related herds considered as "clinically affected" according to EFSA recommendations: 18.1 %). Between the eight departements where goat farms had notified series of abortions, the proportion of abortive episodes attributed to Q fever varied greatly from 0% to 36.4%. In addition to reinforcing knowledge about Q fever, this study enabled obtaining useful field feedbacks on feasibility and acceptability of such surveillance programs before extension to other abortive infectious agents and to the whole territory.

Depuis octobre 2016, l'Europe a connu un des episodes d'influenza aviaire les plus importants au cours de ces dernieres annees, impactant de facon consequente aussi bien l'avifaune sauvage que les elevages de volailles. Cet episode est du a la propagation de virus H5N8, H5N5 et H5N6 originaires d'Asie, et qui sont differents des virus H5N8 et H5N1 qui avaient respectivement ete impliques en 2014 et en 2015. Le nombre total de foyers et de cas d'IAHP notifies au 28 mai 2017 etait de 2 702, dont 1 532 au sein de l'avifaune sauvage (78 especes differentes touchees), 1 123 en elevage et 47 au sein de l'avifaune captive. Cet article presente et analyse l'evolution spatio-temporelle des cas et des foyers entre octobre 2016 et fin mai 2017. (Resume d'auteur)

L'influenza aviaire (IA) est une menace permanente, qui arrive parfois en Europe par le biais des oiseaux migrateurs. Un dispositif de surveillance est en place en permanence pour surveiller les mortalites dans l'avifaune, et particulierement celles des oiseaux d'eau migrateurs. En octobre 2016, un episode d'IA H5N8 qui etait surveille depuis sa survenue en Republique de Touva (Federation de Russie, avril 2016) s'est declare en Europe. Il a entraine des pertes consequentes dans certaines populations d'oiseaux sauvages en Europe, ainsi que dans des filieres avicoles. La situation en France s'est revelee paradoxale : l'atteinte a ete majeure dans la filiere avicole de canards gras du Sud- Ouest, mais les cas dans la faune sauvage sont restes peu nombreux et circonscrits. Ce n'est pas faute d'avoir renforce la surveillance, soit evenementielle (analyse des oiseaux trouves morts) soit active autour des foyers domestiques. Plus de 800 cadavres d'oiseaux sauvages ont ete analyses, dont beaucoup d'anatides, 90 ont ete detectes infectes regroupes en 55 cas dans l'avifaune libre et captive, et dix sites strategiques ont fait l'objet d'une recherche intensifiee des cadavres et n'ont permis de trouver aucun cas positif supplementaire. Plus de 300 oiseaux commensaux des elevages domestiques foyers ont ete analyses et se sont tous reveles negatifs. Les performances du systeme de surveillance ne semblent pas pouvoir etre mises en cause, et il apparait donc qu'il y a bien eu des differences de circulation du virus par rapport a nos voisins d'outre-Rhin, mal expliquees a ce stade mais la situation en France est similaire a celle observee en Italie et en Espagne cet hiver, et correspond assez bien a l'episode H5N8 qui avait circule en Europe fin 2014/debut 2015, sans toucher la France. (Resume d'auteur)

The spatial and temporal study of the spread of emerging infectious diseases is crucial to understand their epidemiology and evaluate the risk of introduction into disease-free areas. In this paper, we present a generic method that models the spread rate of emerging infectious diseases that we applied to Lumpy Skin Disease (LSD), a current epizooty affecting cattle in the Balkans, from May 2015 to July 2016. In the study period, 824 outbreaks of LSD were reported in eight countries. Hotspots of viral transmission were identified mainly south of the Turkish/Greek border, southwest of Bulgaria and south of the Serbian/Bulgarian border. By using Thin Plate Spline Regression (TPSR) to interpolate the week of first invasion, we estimated the spread rate based on the mean duration of time for the infection to spread across a given area (1km). The median spread rate was 7.8km per week, with an interquartile interval of 4.6 to 13.7km and a maximum value reaching 375.6km. The distribution of spread rate indicates two diffusion processes: a localised diffusion covering small distances and suggesting vector transmission, and a diffusion at greater distances possibly due to anthropogenic movement of infected animals. Further research should focus on identifying environmental and socio-economic factors that might influence the spread of LSD to better understand the disease epidemiology and suggest targeted control measures. (Resume d'auteur)

Maintaining vigilance with regard to the introduction of exotic diseases is a challenge, particularly because these diseases are numerous, some are not well known, and they are not immediately suspected by people in day-to-day practice, specifically veterinary practitioners. The objective of this article is to present a tool to support the identification of suspect cases of exotic diseases in cattle, based on a Bayesian approach. A list of 22 exotic diseases in mainland France was selected mainly on the basis of their potential consequences if introduced, and the ability to detect them on a clinical basis. In response of a set of epidemio-clinical criteria observed in the field this tool provides a list of exotic diseases by descending order of likelihood. The tool's performance was assessed by simulation. When simulating epidemio-clinical observations of each of the 22 diseases included in the tool with some uncertainty, the right disease was ranked in the first place between 83.8% and 100% of the times, and always in the five most likely diseases. Even when some noise was introduced in the epidemio-clinical observations simulated by addition of criteria non-characteristic of the simulated diseases, the right disease was always in the five most likely diseases. This tool could be usefully included in a global approach aiming to improve vigilance against exotic diseases.

In epidemiology, data are often aggregated using administrative boundaries or regular spatial lattices. Iso-population partitioning methods allow the aggregation of small units for which population data are available into larger units that are contiguous, as compact as possible, and have a similar population size. The objective of this paper was to study the influence of three spatial data aggregation approaches on data visualization and data analysis: iso-populated units (IPUs), administrative units, and iso-geometric units. This study was conducted using results and simulations from the brucellosis clinical surveillance system for dairy cattle in France. Our findings indicate that using spatial partitioning methods for generating IPUs enhances the ability to interpret the spatial distribution of epidemiological indicators under study. In addition, it provides information on population density and improves the consistency of the power of statistical tests across units. By defining the target population size per spatial unit, IPUs can be used to control the statistical power of a study. Finally, by adding criteria based on environmental factors to generate spatial units, they can be used to control the variation of exposure to these factors within the units.