Exploring the Wind-Borne Spread of Highly Pathogenic Avian Influenza H5N8 During the 2016-2017 Epizootic in France.

In winter 2016-2017, highly pathogenic avian influenza (HPAI) H5N8 virus spread in France, causing an unprecedented epizootic. During the epidemic, southwest France, where most outbreaks were reported, experienced severe weather, with three consecutive storms (Leiv, Kurt, and Marcel) from 3 to 5 February 2017. Although little information is available, one hypothesis is that the spread of HPAI-H5N8 from an infected poultry holding could have been passively facilitated by prevailing wind during the risk period. The aim of this study was therefore to assess the contribution of the wind-borne route to the spatial distribution of HPAI H5N8 outbreaks during the risk period at the beginning of February 2017. The PERLE model, an atmospheric dispersion model (ADM) developed by Météo-France, the French meteorological agency, was used to generate the predicted area at risk of infection from a suspected point source. Model outputs show that the spatial pattern of dust-particle deposition was directed east-southeast in accordance with wind direction. This contrasted with the spatial distribution of HPAI H5N8 outbreaks, which spread westward. These observations suggest that the wind-borne route alone was insufficient to explain the spatial distribution of outbreaks over large distances in southwest France at the beginning of February 2017. Finally, this study illustrates the relevance of close collaboration between governmental authorities, veterinary research institutes, and meteorological agencies involving interdisciplinary research for successful outbreak investigations.

Nota de investigación- Exploración de la propagación por el viento del virus de la influenza aviar altamente patógena H5N8 durante la epizootia entre los años 2016­2017 en Francia. En el invierno 2016-2017, el virus de la influenza aviar altamente patógena subtipo H5N8 se propagó en Francia y causó una epizootia sin precedentes. Durante la epidemia, en el suroeste de Francia, donde se registraron la mayoría de los brotes, se registró clima severo, con tres tormentas consecutivas (Leiv, Kurt y Marcel) del 3 al 5 de febrero del 2017. Aunque hay poca información disponible, una hipótesis es que la propagación del virus de influenza aviar de alta patogenicidad H5N8 desde una explotación avícola infectada podría haberse facilitado pasivamente por los vientos dominantes durante el período de riesgo. El objetivo de este estudio fue, por lo tanto, evaluar la contribución de la ruta del viento en la distribución espacial de los brotes de influenza aviar de alta patogenicidad H5N8 durante el período de riesgo a principios de febrero del 2017. El modelo PERLE, un modelo de dispersión atmosférica (ADM) desarrollado por la agencia meteorológica francesa Météo-France, fue utilizado para generar el área pronosticada en riesgo de infección a partir de una fuente sospechosa. Los resultados del modelo muestran que el patrón espacial de la deposición de partículas de polvo se dirigió al este-sureste de acuerdo con la dirección del viento. Esto contrastó con la distribución espacial de los brotes de influenza aviar de alta patogenicidad H5N8, que se extendieron hacia el oeste. Estas observaciones sugieren que la ruta por el viento por sí sola no fue suficiente para explicar la distribución espacial de los brotes en grandes distancias en el suroeste de Francia a principios de febrero de 2017. Finalmente, este estudio ilustra la relevancia de la estrecha colaboración entre las autoridades gubernamentales, los institutos de investigación veterinaria y agencias meteorológicas, que se involucren en investigación interdisciplinaria para la investigación exitosa de los brotes.

Duck production systems and highly pathogenic avian influenza H5N8 in France, 2016-2017.

In winter 2016-2017, Highly Pathogenic Avian Influenza (HPAI) H5N8 virus spread across Europe, causing unprecedented epizootics. France was massively affected, resulting in the culling of over 6 million poultry. Boosted regression tree (BRT) models were used to quantify the association between spatial risk factors and HPAI H5N8 infection in poultry holdings and to generate predictive maps for HPAI infection. Three datasets were combined to build the model: a dataset of the reported outbreaks in poultry, a dataset of the poultry holdings where the virus has not been reported and a set of relevant spatial risk factors, including poultry production and trade, and water bird habitat. Results identified key associations between the 'foie gras' production systems and HPAI H5N8 risk of occurrence and indicate that strengthening surveillance of fattening duck production systems and making the transportation of fattening ducks more secure would be key priority options for HPAI prevention and control.

A case of unilateral periorbital cellulitis and mandibular osteomyelitis in a turkey flock.

A farm of meat turkeys was affected by a condition, clinically characterized by unilateral inflammation of the orbital region and progressive crossing of the beak, observed in three successive flocks in 2010. While no toxic, genetic, technical, or diet causes could be found, pathologic and bacteriologic analyses were conducted to investigate the case. Pathologic analyses of the heads of affected birds showed blepharitis and exudative sinusitis as well as severe chronic osteomyelitis of all skull bones and mandibula. Staphylococcus aureus was consistently isolated from these lesions. It is supposed that the severe bacterial osteomyelitis induced deviation of some bones, thereby leading to deviation of the beak. Further investigations remain to be carried out to explain these successive outbreaks of staphylococcal osteomyelitis in skull bones.

Length variations in the NA stalk of an H7N1 influenza virus have opposite effects on viral excretion in chickens and ducks.

A deletion of ∼20 amino acids in the stalk of neuraminidase is frequently observed upon transmission of influenza A viruses from waterfowl to domestic poultry. A pair of recombinant H7N1 viruses bearing either a short- or long-stalk neuraminidase was genetically engineered. Inoculation of the long-stalk-neuraminidase virus resulted in a higher cloacal excretion in ducks and led conversely to lower-level oropharyngeal excretion in chickens, associated with a higher-level local immune response and better survival. Therefore, a short-stalk neuraminidase is a determinant of viral adaptation and virulence in chickens but is detrimental to virus replication and shedding in ducks.

A novel polyomavirus (goose hemorrhagic polyomavirus) is the agent of hemorrhagic nephritis enteritis of geese.

We have identified the etiological agent of hemorrhagic nephritis enteritis of geese (HNEG), a fatal disease of European geese. HNEG has been recognized in almost all goose breeding areas, with an epizootic pattern, and up to now, the infectious agent has remained unknown. In order to identify the causative agent, infected tissues from HNEG-affected geese were inoculated to 1-day-old goslings, which then developed clinical signs typical of HNEG. Tissue homogenates from these birds were subjected to Freon extraction followed by sucrose density gradient ultracentrifugation. The resulting main band was examined by electron microscopy and consisted of spherical, naked, papovavirus-like particles approximately 45 nm in diameter. The virus was isolated and propagated in goose kidney cell primary culture. Tissue- or culture-purified virus allowed the experimental reproduction of the disease in goslings. Random PCR amplification of viral nucleic acid produced a 1,175-bp fragment which was shown to be associated with field samples collected from geese affected by HNEG on commercial farms in France. Sequence analysis of the PCR product revealed a unique open reading frame, showing 63 to 72% amino acid similarity with the major capsid protein (VP1) of several polyomaviruses. Finally, based on phylogenetic analysis, we conclude that the causative agent of HNEG is closely related to but clearly distinct from other polyomaviruses; we thus have named this newly identified virus Goose hemorrhagic polyomavirus.

Hypothalamic extract influences a blood-brain barrier model of porcine brain capillary endothelial cells.

The purpose of this study was to investigate the influence of hypothalamic extract, astrocyte coculture, and astrocyte-conditioned medium on the barrier function of an in vitro model of the blood-brain barrier. Porcine brain capillary endothelial cells were grown on polycarbonate membranes suspended between two chambers of media, representing the capillary lumen and brain interstitium. Endothelial cells grown alone and cocultured with astrocytes were cultured in growth medium with or without 50 micrograms/mL hypothalamic extract. An additional treatment consisted of endothelial cells cultured in growth medium that was first conditioned by astrocytes. Coculture consisted of a noncontact model with astrocytes attached to the bottom of the abluminal chamber. Barrier function of the endothelial cells was tested on days 1 through 9 post-seeding by measuring permeability to macromolecules (albumin) and small ions (electrical resistance). Resistance to the passage of macromolecules and small ions was greatest for endothelial cells grown without astrocytes in growth medium supplemented with hypothalamic extract. This barrier was maximal during days 4 through 7 post-seeding and was significantly less permeable than the barrier formed by endothelial cells grown in un-supplemented growth medium, in coculture with astrocytes, or in astrocyte-conditioned medium. These results demonstrate that a noncontact coculture with astrocytes did not enhance the integrity of this in vitro BBB model employing porcine brain capillary endothelial cells, but barrier function was increased when the model's medium was supplemented with hypothalamic extract.

[Determination of cerebrospinal fluid proteins using the Cobas Fara centrifugal analyser. Adaptation of the turbidimetric technic to benzethonium chloride]. / Détermination de la protéinorachie sur analyseur centrifuge Cobas Fara. Adaptation de la technique turbidimétrique au chlorure de benzethonium.

The authors have adapted a turbidimetric assay on centrifugal Cobas Fara analyser for cerebrospinal fluid proteins determinations. The later method is proposed by SFBC Protein Analysis Committee using benzethonium chloride as monoreagent. This adaptation is more sensitive than manual method. The linearity range is greater (0.08-1.85 g/l instead of 0.2-1.2 g/l). Sample assay and time of analysis were reduced by 90 p. cent.

[Prognostic value of prostatic acid phosphatase in stage B and C prostatic cancer. Apropos of 84 cases]. / Intérêt pronostique de la phosphatase acide prostatique dans les cancers de la prostate de stades B et C. A propos de 84 cas.

The authors have studied the prognostic interest of evaluating the prostatic acid phosphatase level before any treatment in 84 cases of stage B and C prostatic cancer. An abnormal PAP level did not significantly modify the 5-year life expectancy of patients, but was significantly correlated with a shorter period of disease-free survival. An abnormal PAP level increased the risk of recurrence; the higher the PAP level, the shorter the disease-free interval was. The disease stage (i.e., B or C) did not modify the 5-year survival period or the length of the remission. The prognosis is worse for a stage B prostatic cancer with a pathological PAP level than for a stage C cancer with a normal PAP level. A pathological PAP level seems to indicate the presence of occult metastases and should incite the clinician to actively investigate the matter.