Progress towards rabies control and elimination in Vietnam.

Rabies is a fatal viral disease that causes an estimated 59,000 human deaths each year. The majority of these deaths occur in developing countries in Asia. Canine rabies is endemic to Vietnam, which is, however, moving towards the disease's elimination. Many countries, such as Vietnam, have invested tremendous resources in controlling rabies, highlighting the goal of regional and global elimination of this neglected disease. In Vietnam, rabies is recognised as one of five high-priority, zoonotic diseases by the Ministry of Health and the Ministry of Agriculture and Rural Development. Investment by the government and by international partners for rabies prevention and control has played a substantial role in reducing human rabies deaths from 404 cases in 1992 to 74 cases in 2017. The catalyst for this effort was the Prime Minister's creation of the National Rabies Program in 1996, which led to increased support and resources for rabies prevention and control. Interventions carried out since then include the expansion of post-exposure prophylaxis centres throughout the country, the introduction or revision of key legislation and guidelines, and improved multisectoral One Health collaboration. In addition, support from international partners, such as the World Organisation for Animal Health (OIE), the World Health Organization (WHO), the Food and Agriculture Organization of the United Nations (FAO), and the Centers for Disease Control and Prevention (CDC), has helped to increase awareness, manage dog populations more effectively, and improve Vietnam's surveillance and diagnostic capabilities. To pursue the goal of eliminating dog-mediated rabies in Vietnam, political commitment is crucial. Resources must be made available to enforce the regulations and guidelines that will enable Vietnam to achieve greater canine rabies vaccination coverage. In this paper, the authors provide an overview of the animal and human health systems in Vietnam, as well as past, current and future directions of rabies prevention and control.

La rage est une maladie virale à l'issue mortelle faisant chaque année un nombre estimé de 59 000 victimes humaines. La plupart de ces décès surviennent dans les pays en développement d'Asie. Au Vietnam, la rage canine est endémique mais le pays poursuit activement l'objectif d'éliminer la rage de son territoire. À l'instar du Vietnam, plusieurs pays ont investi des ressources colossales pour contrôler la rage, renforçant ainsi la dimension régionale et mondiale de l'objectif d'élimination de cette maladie négligée. Au Vietnam, la rage figure parmi les cinq zoonoses hautement prioritaires prises en compte par le ministère de la Santé et le ministère de l'Agriculture et du développement rural. Les investissements consacrés à la prévention et au contrôle de la rage par le gouvernement et ses partenaires internationaux ont joué un rôle déterminant dans la réduction du nombre de décès humains dus à la rage, qui est passé de 404 cas en 1992 à 74 cas en 2017. L'élément catalyseur de cet effort a été la création en 1996 du Programme national de lutte contre la rage par le premier ministre de l'époque, ce qui a permis de renforcer les ressources et le soutien dédiés à la prévention et à la lutte contre la rage. Depuis lors, les interventions ont porté sur la création de centres de prophylaxie post-exposition sur tout le territoire, l'introduction ou la révision de la législation et des lignes directrices applicables et l'amélioration de la collaboration Une seule santé. En outre, le soutien de partenaires internationaux tels que l'Organisation mondiale de la santé animale (OIE), l'Organisation mondiale de la santé (OMS), l'Organisation des Nations Unies pour l'alimentation et l'agriculture (FAO) et les Centres pour le contrôle et la prévention des maladies (CDC, États-Unis d'Amérique) a abouti à une meilleure sensibilisation, à une gestion plus efficace des populations de chiens et à un renforcement des capacités de surveillance et de diagnostic au Vietnam. Un engagement politique fort est indispensable pour réussir à éliminer totalement la rage transmise par les chiens au Vietnam. Des ressources doivent être rendues disponibles afin de mettre en oeuvre la réglementation et les lignes directrices pertinentes et d'augmenter ainsi la couverture vaccinale de la population canine du pays. Les auteurs décrivent les systèmes de santé animale et publique du Vietnam ainsi que les orientations passées, actuelles et futures de la prévention et du contrôle de la rage dans le pays.

La rabia es una enfermedad vírica fatal, que según las estimaciones mata a 59 000 personas al año, mayoritariamente en países en desarrollo asiáticos. La rabia canina es endémica en el Vietnam, país que no obstante avanza ahora hacia la eliminación de la enfermedad. Como el Vietnam, muchos países han invertido cantidades colosales de recursos en la lucha antirrábica, subrayando con ello su compromiso con el objetivo de eliminar esta enfermedad desatendida a escala regional y mundial. El Ministerio de Salud y el Ministerio de Agricultura y Desarrollo Rural del Vietnam tienen catalogada la rabia como una de las cinco enfermedades zoonóticas que revisten máxima prioridad. Las inversiones en prevención y control de la rabia realizadas por el gobierno y por asociados internacionales han ayudado sensiblemente a reducir el número de personas muertas por la rabia, que ha pasado de 404 casos en 1992 a 74 en 2017. El catalizador de este esfuerzo fue la creación en 1996, por iniciativa del Primer Ministro, del Programa Nacional contra la Rabia, que se tradujo en un aumento del apoyo y los recursos destinados a prevenir y combatir la enfermedad. Entre otras intervenciones, desde entonces se ha multiplicado en todo el país el número de centros donde se dispensa profilaxis tras la exposición, se han promulgado o revisado leyes, decretos y directrices fundamentales y se ha mejorado la colaboración multisectorial en clave de Una sola salud. Además, el respaldo de asociados internacionales como la Organización Mundial de Sanidad Animal (OIE), la Organización Mundial de la Salud (OMS), la Organización de las Naciones Unidas para la Alimentación y la Agricultura (FAO) o los Centros para el Control y la Prevención de Enfermedades (CDC) de los Estados Unidos ha ayudado a generar una mayor conciencia del problema, a gestionar más eficazmente las poblaciones de perros y a dotar al país de mejores medios de vigilancia y diagnóstico. Para hacer realidad el objetivo de eliminar del Vietnam la rabia transmitida por perros, la voluntad política es un factor clave, pues hay que poner sobre la mesa los recursos necesarios para aplicar los reglamentos y normas que permitirán al país ampliar la cobertura de vacunación canina antirrábica. Tras trazar una panorámica de los sistemas sanitario y zoosanitario del Vietnam, los autores describen el rumbo pasado, presente y futuro de las labores de prevención y control de la rabia en el país.

Enterohemorrhagic Escherichia coli infection has donor-dependent effect on human gut microbiota and may be antagonized by probiotic yeast during interaction with Peyer's patches.

Enterohemorrhagic Escherichia coli (EHEC) are major food-borne pathogens responsible for serious infections ranging from mild diarrhea to hemorrhagic colitis and life-threatening complications. Shiga toxins (Stxs) are the main virulence factor of EHEC. The antagonistic effect of a prophylactic treatment with the probiotic strain Saccharomyces cerevisiae against EHEC O157:H7 was investigated using complementary in vitro human colonic model and in vivo murine ileal loop assays. In vitro, the probiotic treatment had no effect on O157:H7 survival but favorably influenced gut microbiota activity through modulation of short-chain fatty acid production, increasing acetate production and decreasing that of butyrate. Both pathogen and probiotic strains had individual-dependent effects on human gut microbiota. For the first time, stx expression was followed in human colonic environment: at 9 and 12 h post EHEC infection, probiotic treatment significantly decreased stx mRNA levels. Besides, in murine ileal loops, the probiotic yeast specifically exerted a trophic effect on intestinal mucosa and inhibited O157:H7 interactions with Peyer's patches and subsequent hemorrhagic lesions. Taken together, the results suggest that S. cerevisiae may be useful in the fight against EHEC infection and that host associated factors such as microbiota could influence clinical evolution of EHEC infection and the effectiveness of probiotics.

Awareness of rabies prevention and control measures among public health workers in Northern Vietnam.

OBJECTIVES: To assess and compare rabies related knowledge and awareness of public health workers at provincial and district levels in the seven provinces with the highest number of deaths from human rabies in northern Vietnam. STUDY DESIGN: A cross-sectional study. METHOD: A survey was administered to a convenience sample of public health workers attending four workshops on rabies disease, control and prevention between 16 October and 21 November, 2012. Total knowledge scores (maximum 38 points) were categorized into: 'high' (>30 points) 'moderate' (21-30) and 'low' (<21). The Chi-square test was used to evaluate the statistical significance of the differences in responses between the respondents. RESULTS: Of the 105 public health workers attending the workshops: 57% were male; 76% worked at the district level compared with 24% who worked at provincial level; and 45% had worked in rabies control for <1 year compared with 11% who had worked in rabies control for >5 years. Overall knowledge was patchy and ranked as 'moderate'. Important gaps in knowledge were identified particularly in relation to indications for rabies vaccine and rabies immunoglobulin, and routes of exposure to rabies virus. One in ten respondents did not know that rabies virus could be transmitted by the bite of an infected animal. When examining the overall mean knowledge scores, marginally significant differences were identified. The average scores for district level health workers (DLHW) and provincial level health workers (PLHW) were 28 ± 3 and 29 ± 3 points respectively (p = 0.098), which fell within the study definition of 'moderate' knowledge. In contrast, when 'high' knowledge scores were compared, a significantly greater proportion of PLHW achieved >30 points compared to DLHW (44.0% vs 22.5%, p = 0.044). CONCLUSIONS: Important gaps in knowledge and awareness of public health workers were identified particularly in relation to routes of exposure to rabies virus and indications for rabies vaccine and rabies immunoglobulin. Overall, comparison of knowledge scores revealed significant differences between district and provincial public health workers. The results obtained suggest that in order for rabies control programmes to succeed public health workers at all levels need to have accurate and evidence-based knowledge. This may be facilitated by improving the quantity and quality of their training and education.

Zinc hydroxychloride supplementation improves tibia bone development and intestinal health of broiler chickens.

This study was conducted to investigate the effects of zinc (Zn), as a combination of oxide (ZnO) and sulfate (ZnSO4), compared with incremental levels of zinc hydroxychloride (ZH) on tibia traits, intestinal integrity, expression of selected jejunal genes, cecal short chain fatty acids and microbial composition in broilers. Day-old male Ross 308 chicks (n = 784) were randomly allocated to seven dietary treatments, each replicated seven times with 16 chicks per replication. The dietary treatments included a negative control diet (NC) with no supplemental Zn, a positive control (PC) with 100 mg/kg supplemental Zn from an ionic bound source combination (50 mg/kg ZnO + 50 mg/kg ZnSO4), and the NC diet supplemented with one of 20, 40, 60, 80, or 100 mg/kg Zn as ZH. The diets were fed over starter (1-14 d) and grower (14-35 d) phases, with tissue and digesta samples collected from 3 birds per replicate on days 14 and 35. The results showed that dietary Zn level had a significant effect on tibia breaking strength on d 35 (P < 0.05), and tibia Zn concentration both on d 14 and d 35 (P < 0.01). Dietary Zn levels linearly (P < 0.01) increased cecal lactic acid production, increased Lactobacillus, and decreased Bacillus and total bacteria counts (P < 0.05). Inclusion of 80 and 100 mg/kg Zn as ZH tended to upregulate the expression of claudin-1 (P = 0.088) and tight junction protein-1 (P = 0.086). The results obtained in this study suggest that a non-Zn supplemented diet can negatively influence tibia development and gut microbiota composition in broiler chickens. Higher supplemental Zn in the diet alters cecal microbiota population in favor of Lactobacillus and can decrease the total bacterial load. Supplemental Zn level in the feed have the potential to manipulate the jejunal gut integrity at a molecular level.

Copper hydroxychloride is more efficacious than copper sulfate in improving broiler chicken's growth performance, both at nutritional and growth-promoting levels.

This study was designed to compare the effects of nutritional and growth-promoting levels of copper hydroxychloride (CH) with copper sulfate (CuSO4) on growth, carcass characteristics, tibia traits and mineral concentration in broilers fed a conventional wheat-soybean meal-based diet. Day-old Ross 308 male chicks (n = 864) were randomly assigned into 8 dietary treatments with 6 replicates of 18 chicks per treatment. The dietary treatments included a basal diet containing no supplemental copper (Cu) serving as the negative control (NC); basal diet supplemented with 15 or 200 mg/kg Cu as CuSO4; basal diet supplemented with either 15, 50, 100, 150, or 200 mg/kg Cu from CH. Diets were fed over the starter (day 1-14) and grower (day 14-35) phases. Birds in the NC group gained the same body weight and had similar feed conversion ratio (FCR) to birds receiving 15 mg/kg Cu as CuSO4, but birds receiving 15 mg/kg Cu as CH had a lower FCR than the NC birds (day 0-35; P < 0.05). Birds fed 200 mg/kg Cu as CH gained more weight (77 g/bird) and had a lower FCR (3.2 point) compared with those fed 200 mg/kg Cu as CuSO4 (P < 0.01). Based on broken-line regression models, the optimum inclusion level of Cu as CH in the diet for optimal body weight gain and FCR were estimated to be 109.5 and 72.3 mg/kg, respectively (P < 0.001). Carcass characteristics were not affected by dietary Cu sources or levels (P > 0.05). The highest and lowest tibia ash content were observed in birds fed diet with 150 mg/kg Cu as CH and 200 mg/kg Cu as CuSO4, respectively (P < 0.05). Supplementation with 200 mg/kg Cu as CH resulted in higher duodenal mucosa Cu content compared with the diet containing 200 mg/kg Cu as CuSO4 (P < 0.001). In conclusion, supplementation of Cu from CH was more efficacious than CuSO4 in promoting growth performance, both at nutritional and pharmacological levels.

Engineering of Saccharomyces cerevisiae for the production of dihydroxyacetone (DHA) from sugars: a proof of concept.

Dihydroxyacetone (DHA) has numerous industrial applications. In this work, we pursue the idea to produce DHA from sugars in the yeast Saccharomyces cerevisiae, via glycerol as an intermediate. Firstly, three glycerol dehydrogenase (GDH) genes from different microbial sources were expressed in yeast. Among them, the NAD(+)-dependent GDH of Hansenula polymorpha showed the highest glycerol-oxidizing activity. DHA concentration in shake-flask experiments was roughly 100mg/lDHA from 20g/l glucose, i.e. five times the wild-type level. This level was achieved only when cultures were subjected to osmotic stress, known to enhance glycerol production and accumulation in S. cerevisiae. Secondly, DHA kinase activity was abolished to prevent conversion of DHA to dihydroxyacetone phosphate (DHAP). The dak1Deltadak2Delta double-deletion mutant overexpressing H. polymorpha gdh produced 700mg/l DHA under the same conditions. Although current DHA yield and titer still need to be optimized, our approach provides the proof of concept for producing DHA from sugars in yeast.

Fermentative production of L-glycerol 3-phosphate utilizing a Saccharomyces cerevisiae strain with an engineered glycerol biosynthetic pathway.

Interest in L-glycerol 3-phosphate (L-G3P) production via microbial fermentation is due to the compound's potential to replace the unstable substrate dihydroxyacetone phosphate (DHAP) in one-pot enzymatic carbohydrate syntheses. A Saccharomyces cerevisiae strain with deletions in both genes encoding specific L-G3Pases (GPP1 and GPP2) and multicopy overexpression of L-glycerol 3-phosphate dehydrogenase (GPD1) was studied via small-scale (100 mL) batch fermentations under quasi-anaerobic conditions. Intracellular accumulation of L-G3P reached extremely high levels (roughly 200 mM) but thereafter declined. Extracellular L-G3P was also detected and its concentration continuously increased throughout the fermentation, such that most of the total L-G3P was found outside the cells as fermentation concluded. Moreover, in spite of the complete elimination of specific L-G3Pase activity, the strain showed considerable glycerol formation suggesting unspecific dephosphorylation as a mechanism to relieve cells of intracellular L-G3P accumulation. Up-scaling the process employed fed-batch fermentation with repeated glucose feeding, plus an aerobic growth phase followed by an anaerobic product accumulation phase. This produced a final product titer of about 325 mg total L-G3P per liter of fermentation broth.

Knowledge of Rabies Prevention in Vietnamese Public Health and Animal Health Workers.

Rabies is an invariably fatal, but preventable zoonotic disease. Despite a national programme for its prevention and control, the number of rabies associated deaths in Vietnam has increased in recent years. A cross-sectional survey was undertaken in 2012 to assess and compare the knowledge, awareness and practices of 189 public health workers (PHW) and animal health workers (AHW) attending a joint training course for professionals from provinces in northern Vietnam with the highest number of deaths from rabies. Questionnaires facilitating self-evaluation were provided, and total knowledge scores were calculated (maximum 38 points) and categorized into: 'high' (>30 points), 'moderate' (21-30) and 'low' (<21). The response rate was 100%, and among the 189 participants, 56% were PHW compared to 44% who were AHW. Although most respondents knew rabies could be transmitted through the bite of an animal, most commonly a dog, and that rabies is a preventable disease, significant differences between groups were identified. Major areas included poor knowledge of common rabies reservoirs, wound management and guidance on post-exposure prophylaxis. Overall, the total mean knowledge scores for PHW was significantly higher (P = 0.011) compared to those for AHW, but both scores fell within the 'moderate' knowledge range. However, proportionately more PHW than AHW achieved 'high' knowledge scores (P = 0.0098). To our knowledge this is the first published study to simultaneously assess the knowledge and awareness of animal health and public health professionals attending joint training activities aimed at strengthening rabies prevention and control. To ensure effective prevention and control of rabies requires that AHW and PHW not only coordinate and collaborate, but have a common knowledge and understanding of rabies prevention and control measures. This study provides important baseline data in a relatively unexplored area of research that can focus future interventions and research.

Specific airway resistance in healthy young Vietnamese and Caucasian adults.

In healthy Vietnamese children the respiratory resistance has been suggested to be similar at 110 cm height but larger at 130 cm when compared with data in Caucasians from the literature, suggesting smaller airways in older Vietnamese children (Vu et al., 2008). The hypothesis tested here is whether the difference in airway resistance remains consistent throughout growth, and if it is larger in adult Vietnamese than in Caucasians. Airway resistance and Functional Residual Capacity were measured in healthy young Caucasian and Vietnamese adults in their respective native country using identical equipment and protocols. Ninety five subjects in Vietnam (60 males) and 101 in France (41 males) were recruited. Airway resistance was significantly larger in Vietnamese than in Caucasians and in females than in males, consistent with difference in body dimensions. Specific airway resistance however was not different by ethnicity or gender. The findings do not support the hypothesis that airway size at adult age - once normalized for lung volume - differs between Vietnamese and Caucasians.

Collection of Oral Fluids Using Cotton Ropes as a Sampling Method to Detect Foot-and-Mouth Disease Virus Infection in Pigs.

In high-density farming practices, it is important to constantly monitor for infectious diseases, especially diseases that have the potential to spread rapidly between holdings. Pigs are known to amplify foot-and-mouth disease (FMD) by excreting large amounts of virus, and it is therefore important to detect the virus quickly and accurately to minimize the spread of disease. Ropes were used to collect oral fluid samples from pigs, and each sample was compared to saliva samples collected from individual animals by detecting FMD virus RNA using real-time PCR. Two different experiments are described where groups of pigs were infected with different serotypes of FMD virus, either with or without vaccination, and unvaccinated pigs were kept in aerosol contact. The sensitivity of the rope sampling varied between 0.67 and 0.92, and the statistical agreement between this method and individual sampling ranged from substantial to moderate for the two different serotypes. The ease of collecting oral fluids using ropes together with the high sensitivity of subsequent FMD detection through PCR indicates that this could be a useful method to monitor pig populations for FMD virus infection. With further validation of the sensitivity of detection of FMD virus RNA, this can be a cost-effective, non-invasive diagnostic tool.

Peak bone mineral density in Vietnamese women.

SUMMARY: This cross-sectional study showed that peak bone mineral density in Vietnamese women is comparable to that in Caucasian women; however, the prevalence of osteoporosis in post-menopausal Vietnamese women was slightly higher than in Caucasian women. The age of achieving peak bone mass in Vietnamese women was between 26 and 30 years. INTRODUCTION: While peak bone mass and its determinants have been well-documented in Caucasian populations, little has been studied in Asian populations. The present study was designed to estimate the peak bone mineral density (BMD), age of its attainment, and to examine the prevalence of osteoporosis in Vietnamese women aged 50+. METHODS: The study was designed as a cross-sectional study with 328 women aged between 10 and 65 years (average age: 41) who were randomly selected from two districts around Hanoi city according to a stratified sampling scheme. BMD at the lumbar spine, femoral neck and total hip was measured by a DXA instrument (GE Lunar Prodigy, WI, USA). BMD was modeled as a cubic function of age, from which peak BMD and age at peak BMD were estimated. Bootstrap method was utilized to estimate the 95% confidence interval of peak BMD and age at peak BMD. From the peak BMD, T-score was calculated for each woman, and using the World Health Organization criteria, any woman with femoral neck BMD T-score

Clonal distribution of superantigen genes in clinical Staphylococcus aureus isolates.

Staphylococcus aureus is both a successful human commensal and a major pathogen. The elucidation of the molecular determinants of virulence, in particular assessment of the contributions of the genetic background versus those of mobile genetic elements (MGEs), has proved difficult in this variable species. To address this, we simultaneously determined the genetic backgrounds (spa typing) and the distributions of all 19 known superantigens and the exfoliative toxins A and D (multiplex PCR) as markers for MGEs. Methicillin- sensitive S. aureus strains from Pomerania, 107 nasal and 88 blood culture isolates, were investigated. All superantigen-encoding MGEs were linked more or less tightly to the genetic background. Thus, each S. aureus clonal complex was characterized by a typical repertoire of superantigen and exfoliative toxin genes. However, within each S. aureus clonal complex and even within the same spa type, virulence gene profiles varied remarkably. Therefore, virulence genes of nasal and blood culture isolates were separately compared in each clonal complex. The results indicated a role in infection for the MGE harboring the exfoliative toxin D gene. In contrast, there was no association of superantigen genes with bloodstream invasion. In summary, we show here that the simultaneous assessment of virulence gene profiles and the genetic background increases the discriminatory power of genetic investigations into the mechanisms of S. aureus pathogenesis.

Engineering of Saccharomyces cerevisiae for the production of L-glycerol 3-phosphate.

L-glycerol 3-phosphate (L-G3P) was accumulated in Saccharomyces cerevisiae by pathway engineering. Intracellular concentration of this metabolic intermediate could be increased more than 20 times compared to the wild type by overexpressing GPD1 encoding the glycerol 3-phosphate dehydrogenase in a gpp1 Delta gpp2 Delta mutant which lacks both isoenzymes of glycerol 3-phosphatase. Investigation of cellular pattern of triacylglycerols and glycerophospholipids did not reveal considerable changes due to accumulation of their precursor L-G3P. Hyperosmotic stress did not affect the L-G3P pool in the gpp1 Delta gpp2 Delta mutant overexpressing GPD1 despite an about 4-fold increase of specific GPD activity. In contrast, oxygen limitation improved intracellular L-G3P concentration by enhancing the availability of cytosolic NADH. The reduction of pyruvate decarboxylase activity by deleting PDC2 led to an additional increase. In fact, the triple mutant gpp1 Delta gpp2 Delta pdc2 Delta overexpressing GPD1 accumulated 17 mg L-G3P/g dry weight during glucose batch fermentation under oxygen limitation. This value corresponds to an about 100-fold increase compared to that found in the wild type.