Influenza surveillance in animals: what is our capacity to detect emerging influenza viruses with zoonotic potential?

A survey of national animal influenza surveillance programmes was conducted to assess the current capacity to detect influenza viruses with zoonotic potential in animals (i.e. those influenza viruses that can be naturally transmitted between animals and humans) at regional and global levels. Information on 587 animal influenza surveillance system components was collected for 99 countries from Chief Veterinary Officers (CVOs) (n = 94) and published literature. Less than 1% (n = 4) of these components were specifically aimed at detecting influenza viruses with pandemic potential in animals (i.e. those influenza viruses that are capable of causing epidemic spread in human populations over large geographical regions or worldwide), which would have zoonotic potential as a prerequisite. Those countries that sought to detect influenza viruses with pandemic potential searched for such viruses exclusively in domestic pigs. This work shows the global need for increasing surveillance that targets potentially zoonotic influenza viruses in relevant animal species.

Emergence of a novel cluster of influenza A(H5N1) virus clade 2.2.1.2 with putative human health impact in Egypt, 2014/15.

A distinct cluster of highly pathogenic avian influenzaviruses of subtype A(H5N1) has been found to emergewithin clade 2.2.1.2 in poultry in Egypt since summer2014 and appears to have quickly become predominant.Viruses of this cluster may be associated withincreased incidence of human influenza A(H5N1) infectionsin Egypt over the last months.

Influenza at the animal-human interface: a review of the literature for virological evidence of human infection with swine or avian influenza viruses other than A(H5N1).

Factors that trigger human infection with animal influenza virus progressing into a pandemic are poorly understood. Within a project developing an evidence-based risk assessment framework for influenza viruses in animals, we conducted a review of the literature for evidence of human infection with animal influenza viruses by diagnostic methods used. The review covering Medline, Embase, SciSearch and CabAbstracts yielded 6,955 articles, of which we retained 89; for influenza A(H5N1) and A(H7N9), the official case counts of t he World Health Organization were used. An additional 30 studies were included by scanning the reference lists. Here, we present the findings for confirmed infections with virological evidence. We found reports of 1,419 naturally infected human cases, of which 648 were associated with avian influenza virus (AIV) A(H5N1), 375 with other AIV subtypes, and 396 with swine influenza virus (SIV). Human cases naturally infected with AIV spanned haemagglutinin subtypes H5, H6, H7, H9 and H10. SIV cases were associated with endemic SIV of H1 and H3 subtype descending from North American and Eurasian SIV lineages and various reassortants thereof. Direct exposure to birds or swine was the most likely source of infection for the cases with available information on exposure.

Research Note: Validation of a new differentiation approach using the commercial ASAPTM media to detect the Salmonella 441/014 vaccine strain.

Vaccination is one of the most important control tools to reduce Salmonella in poultry production. In order for a live vaccine to be licensed for field use it should be provided with the detection methods to differentiate it from field strains. This paper aims to describe the validation of an alternative method for the differentiation of the Salmonella 441/014 vaccine strain from field strains, using a chromogenic Media, ASAP from bioMérieux. The ASAP-based differentiation method was compared with already authorized methods, namely the Anicon SE Kylt PCR DIVA 1 assay and Ceva S-Check Salmonella differentiation kit, following the ISO 16140-6:2019 validation method guidelines. A Generalised Linear Model was fitted to the data to determine the inclusivity and exclusivity of differentiation methods (PCR Kylt vs. S-Check vs. ASAPTM). Statistical differences were based on a P-value level of < 0.05 (SPSS Inc., Chicago, IL). In this study, we show that the ASAP media was able to differentiate Salmonella Enteritidis vaccine strains from field strains, obtaining 100% agreement between the three differentiation assays. This differentiation approach is quicker, easier to deploy and cheaper as compared to alternative methods.

[Atypical clinical presentation of a neuroblastoma in an infant]. / Présentation clinique atypique d'un neuroblastome chez un nourrisson.

A babygirl, aged six weeks, was hospitalized for rectal prolapse and isolated constipation. The investigation revealed a neuroblastoma (NB) inducing a medullar compression responsible for the sphincter disorders. NB is second among pediatric solid tumors, but is the most frequent cancer among infants. Its diagnosis is difficult because of its rarity and the variety of its symptoms. A new staging, based on imaging, has recently been proposed by the International Neuroblastoma Risk Group. With the exception of its localized, easily resectable forms, NB is best treated by chemotherapy.

Evolution of highly pathogenic avian influenza H5N1 viruses in Egypt indicating progressive adaptation.

Highly pathogenic avian influenza (HPAI) virus of the H5N1 subtype was first diagnosed in poultry in Egypt in 2006, and since then the disease became enzootic in poultry throughout the country, affecting the poultry industry and village poultry as well as infecting humans. Vaccination has been used as a part of the control strategy to help to control the disease. Epidemiological data with sequence analysis of H5N1 viruses is important to link the mechanism of virus evolution in Egypt. This study describes the evolutionary pattern of Egyptian H5N1 viruses based on molecular characterization for the isolates collected from commercial poultry farms and village poultry from 2006 to 2011. Genetic analysis of the hemagglutinin (HA) gene was done by sequencing of the full-length H5 gene. The epidemiological pattern of disease outbreaks in Egyptian poultry farms seems to be seasonal with no specific geographic distribution across the country. The molecular epidemiological data revealed that there are two major groups of viruses: the classic group of subclade 2.2.1 and a variant group of 2.2.1.1. The classic group is prevailing mainly in village poultry and had fewer mutations compared to the originally introduced virus in 2006. Since 2009, this group has started to be transmitted back to commercial sectors. The variant group emerged by late 2007, was prevalent mainly in vaccinated commercial poultry, mutated continuously at a higher rate until 2010, and started to decline in 2011. Genetic analysis of the neuraminidase (NA) gene and the other six internal genes indicates a grouping of the Egyptian viruses similar to that obtained using the HA gene, with no obvious reassortments. The results of this study indicate that HPAI-H5N1 viruses are progressively evolving and adapting in Egypt and continue to acquire new mutations every season.

Experiences with vaccination in countries endemically infected with highly pathogenic avian influenza: the Food and Agriculture Organization perspective.

Vaccination has been used extensively for the control and prevention of highly pathogenic avian influenza (HPAI) caused by viruses of the H5N1 subtype in endemically infected countries. The Food and Agriculture Organization views vaccination as a legitimate aid in the control and prevention of infection and disease caused by HPAI viruses but does not see it as a panacea. Vaccination should be used as just one in a number of measures used together to reduce the effect and risk of infection. It will be required for a considerable time in endemically infected countries. The methods used in Vietnam in implementing blanket vaccination against H5N1 HPAI viruses demonstrate the steps that should be considered when introducing vaccination. So far, it has not been possible to determine the precise effect of vaccination in endemically infected countries because it has been used in combination with other measures. Well managed vaccination campaigns will reduce the incidence of infection in poultry and therefore reduce the risk to humans from these viruses. Vaccination was implemented to protect both poultry and humans, with a major goal being to reduce the risk of emergence of a human influenza pandemic virus. Economic analysis of vaccination should focus on cost-effectiveness of proposed strategies. Ex-ante and ex-post evaluation of vaccination campaigns should take into account the benefits generated in the poultry sector and for human health.

Study by NMR of the mode of action of monensin on Streptococcus faecalis de-energized and energized cells.

Streptococcus faecalis was used as a bacterial model for studying the mode of action of monensin by NMR investigations. Experiments were carried out in two states, characterized by several complementary methods: (i) the resting (de-energized) cell which was considered as an inert biological membrane, on which cationic transport induced by the ionophore alone can be investigated; (ii) the active (energized) cell where the ionophore-sensitive response of the living organism, particularly the cation pumps and the glycolysis, is probed. Studies of resting cells were performed, with changing external ionic concentrations, in the presence of monensin, which is preferentially a sodium carrier. Internal and external Na+ and H+ were followed by corresponding 23Na and 31P (inorganic phosphate) NMR resonances, K+ fluxes were measured by atomic absorption. It was shown that the induced cationic movements were linked to the existing ionic gradients for K+ and Na+. 31P and 13C NMR spectra for the intermediary metabolites detected in active cells showed that glycolysis is dramatically modified in the presence of monensin.

Conditions modulating the ionic selectivity of transport by monensin examined on Enterococcus hirae (Streptococcus faecalis) by 23Na-NMR and K+ atomic absorption.

Factors likely to modulate the ionic selectivity of monensin were examined on Enterococcus hirae (Streptococcus faecalis) in two states previously characterized: the resting (de-energized) cell and the active (energized) cell. Internal and external Na+ were followed by corresponding 23Na-NMR resonances K+ concentrations were measured by atomic absorption. For a given cellular population of de-energized cells, the apparent transport rates and the final cationic concentrations reached at the steady state were decreasing with the ionophore dose. Monensin was selective for sodium only at low concentrations, in the range 1 mM-10(-4) mM the transport was depending on the effective cationic gradients. Comparison of the activity curves for two cell populations (7.10(9) and 7.10(10) cells/ml) showed the importance of the ratios of monensin/mg phospholipid and also of the ratios of external/internal volumes. On energized cells, except for low monensin concentrations, the main effect was a K(+)-induced efflux and not a Na+ influx. Two factors were modulating the resulting selectivity of this ionophore: the response of the intrinsic bacterial carriers and the generation of the gradients (mainly the external pH) which were favourable to a K+/Na+ transport. Once again the results obtained for two cell populations could be compared, the determining factors were the ratio external/internal volume and the generation of the pH gradient.

Na+ and K+ transport by 4-chlorophenylurethane-monensin in Enterococcus hirae de-energized and energized cells studied by 23Na-NMR and K+ atomic absorption.

Na+ and K+ movements induced by 4-chlorophenylurethane-monensin, which presents an inverted ion selectivity (K+ > Na+) in model systems compared with monensin, were followed on Enterococcus hirae cells by 23Na-NMR and K+ atomic absorption. For de-energized cells, the urethane derivative is much more selective for K+ than monensin, but only at low concentrations (10(-3)-10(-4) mM). For higher concentrations, as previously shown for monensin, the sodium and potassium movements are driven by the ion gradients present. On energized cells, both K+ and Na+ gradients were highly perturbed, and this can be related to the higher toxicity in mice and bacteria for this derivative.

[West Nile virus infections: overview and epidemiological update]. / Infections par le virus du Nil occidental : synthèse et actualités épidémiologiques.

West Nile virus, a flavivirus transmitted by mosquitoes, has been intensively studied since a few years because of epidemics/epizootics it has caused the last ten years, in particular around the Mediterranean basin and on the North-American continent. This virus mainly circulates in birds ; migrating bird species disseminate the virus while resident species could play a role in viral cycle amplification. A large number of mammal, amphibian and reptile species can also be infected. This virus can cause a lethal disease in humans and horses. For this reason, an active and/or passive surveillance is carried out in France and in United States at different steps of the transmission cycle : insects, birds, horses and humans. This surveillance is aimed at precociously detecting viral circulation and, if detected, take suitable information, prevention and fight measures. Furthermore, the description of new transmission routes of infection has led to precaution measures for blood and organ donations in the US and in a lesser extent, in France. As West Nile epidemiology is only partially known, most of epidemics remain unpredictable and difficult to control.

Study of a delta-hydroxy ketone-hemiketal equilibrium by 2D-NMR exchange spectroscopy for the antibiotic grisorixin: involvement in cationic transport through membranes.

Study of a delta-hydroxyketone-hemiketal equilibrium in the polyether antibiotic grisorixin was performed with 2D-NMR spectroscopy. The efficiency of 13C chemical exchange spectroscopy for the assignment of 1H and 13C resonances, in the 2 forms, was shown, making possible a conformational investigation of both forms. This equilibrium was observed for grisorixin in solvents of varying polarity, such as CD2Cl2, CDCl3, CD3CN, or CD3OD, but not in C6D12 or C6D6. Other related antibiotics with the same terminal heterocycle were described only in the closed hemiacetalic structure. The low ionic fluxes measured in a bulk chloroformic membrane for grisorixin were explained by this equilibrium, which competed unfavorably with the cation capture process at the water-chloroform interface. This equilibrium would not be present in a phospholipidic bilayer membrane containing the ionophore, published experimental results are taken into account. The peculiar tautomeric equilibrium observed for grisorixin could be linked to the specific axial stereochemistry of the C7-C8 bond, which creates tension in the globular conformation.

Ionophore properties of monensin derivatives studied on human erythrocytes by 23Na NMR and K+ and H+ potentiometry: relationship with antimicrobial and antimalarial activities.

Eight derivatives of monensin with a modified C25-C26 moiety were synthesized. Their ionophore properties were studied on human erythrocytes by measuring Na+ influx with 23Na NMR and concomitant K+ and H+ efflux by potentiometry. Modification of OH-26 led to inversion of selectivity of transport in favor of K+/Na+ in comparison with monensin. This selectivity disappeared by suppression of the C26-OH moiety. Finally the ionophore ability was lost if the head-to-tail chelation of the monensin skeleton was prevented by blocking the terminal OH-25 and -26 functions. All the compounds were inactive on Gram-negative bacteria and fungi. MIC measured on Bacillus cereus showed that derivatives with increased K+/Na+ selectivity were clearly the most active against Bacillus growth. Most of the compounds showed potential antimalarial properties in the nanomolar range when tested in vitro against Plasmodium falciparum. The IC50S measured were correlated with the whole Na+ and K+ transport efficiency rather than with the ionic selectivity. In both cases determination of initial fluxes of transport for both cations (Na+ and K+) was necessary to investigate the relationship between biological and ionophore properties.

Use of PFGE typing for tracing contamination with Listeria monocytogenes in three cold-smoked salmon processing plants.

The sites of Listeria monocytogenes contamination in three cold-smoked salmon (Salmo salar) processing plants were detected by sampling salmon and the plant's environment and equipment at different production stages. Of the 141 samples collected from three processing plants, 59 (42%) were contaminated with L. monocytogenes. The rates of contamination varied as to the plant and the sample source. L. monocytogenes isolates from 17 various contaminated seafood products (fresh, frozen and smoked fishes, cooked mussels) were also studied. A total of 155 isolates from the three plants and the various seafoods were characterized by genomic macrorestriction using ApaI and SmaI with pulsed-field gel electrophoresis (PFGE) and 82 isolates were serotyped. Macrorestriction yielded 20 pulsotypes and serotyping yielded four serovars: 1/2a, 1/2b, 1/2c, 4b (or e), with 77 (93%) belonging to serovar 1/2a. One clone of L. monocvtogenes predominated and persisted in plant I and was the only pulsotype detected in the final product although it was not isolated from raw salmon. No L. monocytogenes was detected in the smoked skinned salmon processed in plant II, even though 87% of the raw salmon was contaminated. All the smoked salmon samples collected in plant III were contaminated with a unique clone of L. monocytogenes, which may have occurred during slicing. In the three plants, the contamination of final products did not seem to originate from the L. monocytogenes present on raw salmon, but from the processing environment.

Semi-synthesis of A23187 (calcimycin) analogs. III. Modification of benzoxazole ring substituents, ionophorous properties in an organic phase.

Ten semi-synthetic analogs of A23187 (calcimycin), with only the benzoxazole ring substituents modified together with the ionophore X14885A were studied with regard to their calcium and magnesium carrier properties through an organic phase (toluene - butanol, 70:30). The results indicate that the carboxylic group and the oxazolic nitrogen, maintained in the ortho position are essential for the ionophorous properties. Further, the introduction of a substituent in place of the NHCH3 group, producing steric hindrance of the carboxylic group leads to a destabilization of the 2:1 associations with cations.

Microbial conversion of grisorixin, a monovalent cation ionophorous antibiotic.

The isolation and identification of a bioconversion product of grisorixin from a strain of Streptomyces rimosus is reported. The structure of this product was elucidated from physicochemical data, in particular 13C NMR spectra. Its ionophorous and antibiotic properties are markedly different from those of grisorixin.

Semisynthesis of A23187 (calcimycin) analogs. II. Introduction of a methyl group on the benzoxazole ring.

Semisynthesis of two demethylamino A23187 with a methyl group in the 4- or 5-position on the benzene ring were carried out via the cleavage of A23187 oxazole ring and rebuilding of modified benzoxazoles. These compounds were shown to release Ca++ and MG++ from mitochondria and to keep part the antibacterial activity of the natural metabolite.

Microbial conversion of nigericin in three successive steps, by Sebekia benihana.

A strain of Sebekia benihana NRRL 11111 was found to transform nigericin in three successive steps, giving three compounds which were isolated. Their structure were determined by IR, 1H and 13C NMR, and fast atom bombardment mass spectra. The first compound resulted from the reduction of the terminal hemiketal ring it was then transformed into the two other compounds as a result of the oxidation of methyl (C-33) into a CH2OH and COOH group respectively. All these products had lost the ionophoric and antibiotic properties of nigericin and thus were products of a detoxification process.

Generalised linear mixed models analysis of risk factors for contamination of Danish broiler flocks with Salmonella typhimurium.

We present a retrospective observational study of risk factors associated with the occurrence of Salmonella typhimurium (ST) in Danish broiler flocks. The study is based on recordings from 1994 in the ante-mortem database maintained by the Danish Poultry Council. The epidemiological units are the broiler flocks (about 4000 flocks) which are clustered within producers. Broiler flocks with ST-infected parent stocks show increased risk of salmonella infection, and also the hatchery affects the salmonella status significantly. Among the rearing factors, only the use of medicine as well as the time of rearing, and the sampling method are significant. Epidemiological control would seem most efficient on starting at the top levels of the production hierarchy from which a major part of the ST contamination is derived. A secondary purpose of the study is to evaluate different statistical approaches and software for the analysis of a moderately-sized data set of veterinary origin. We compare the results from five analyses of the generalised linear mixed model (GLMM) type. The first observation is that the results agree reasonably well and lead to similar conclusions. A closer look reveals certain patterns of bias and estimation accuracy that correspond well with theoretical findings and practical experience reported in the statistical literature.

[Intrapericardial congenital ectasias of the left atrium]. / Les ectasies congénitales intrapéricardiques de l'auricule gauche

Congenital intrapericardial dilatation of the left atrium is an abnormality which is either very rare (16 cases reported in the literature) or one that is easily missed. The clinical features are unhelpful, and the diagnosis is suggested by the outline on X ray and confirmed by angiocardiography. The great importance of this abnormality lies in its natural history. Disorders of rythm (9 cases out of 16) and embolism (5 cases out of 16) are amongst the complications to be weighed up when deciding the treatment policy. Operative treatment, which is straightforward, seems to us to be indicated in all cases.