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Background: Japanese encephalitis (JE) virus is recognized as a major cause of encephalitis in Bangladesh. The World Health Organization (WHO) recommends human immunization as the most effective means to control JE. Several WHO-prequalified vaccines are available to prevent JE but no vaccination program has been implemented in Bangladesh. Methods: We conducted hospital-based surveillance for acute meningitis-encephalitis syndrome (AMES) to describe JE epidemiology and help inform policy decisions about possible immunization strategies for Bangladesh. Results: During 2007–2016, a total of 6543 AMES patients were identified at four tertiary hospitals. Of the 6525 patients tested, 548 (8%) were classified as JE cases. These 548 patients resided in 36 (56%) out of 64 districts of Bangladesh, with the highest proportion of JE cases among AMES patients (12% and 7%) presenting at two hospitals in the northwestern part of the country. The median age of JE cases was 30 years, and 193 (35%) were aged ≤15 years. The majority of JE cases (80%) were identified from July through November. Conclusions: Surveillance results suggest that JE continues to be an important cause of meningo-encephalitis in Bangladesh. Immunization strategies including JE vaccine introduction into the routine childhood immunization program or mass vaccination in certain age groups or geographic areas need to be examined, taking into consideration the cost-effectiveness ratio of the approach and potential for decreasing disease burden.

Cyclones are one of the most common and foremost natural hazards in the world that causes extensive causalities. Bangladesh is highly vulnerable to cyclone hazard for its geographical location and socio-economic conditions. This study has aimed to analyze the historical cyclonic hazards and creating vulnerability maps and risk maps for Bangladesh. The apposite variables were selected by reviewing pertinent literatures and necessary data were retrieved for 1900 to 2015. GIS tool has been used for visualization of weighed scores for hazard, vulnerability and risk based on historical cyclones’ intensities, magnitudes, causalities and existing coping capacities. Moreover, hotspot analysis that implies Getis-Ord Gi* spatial statistics was also used in this study to identify the patterns of spatial significance and relationship of areas among their neighbors. This analysis produced Z scores from weighed variables those were proportional to the degree of vulnerability and risk. The low negative to high positive Z scores are correlative of low to high cyclone vulnerability and risk. Consequently, the weighed scores have elicited the coastal areas are in front line in terms of vulnerability and risk to cyclone. Besides, Gi* revealed that some areas are significantly risk prone for being spatially influenced by their neighbors.

Nipah virus (NiV) has been transmitted from patient to caregivers in Bangladesh presumably through oral secretions. We aimed to detect whether NiV-infected patients contaminate hospital surfaces with the virus. During December 2013–April 2014, we collected 1 swab sample from 5 surfaces near NiV-infected patients and tested surface and oral swab samples by real-time reverse transcription PCR for NiV RNA. We identified 16 Nipah patients; 12 cases were laboratory-confirmed and 4 probable. Of the 12 laboratory-confirmed cases, 10 showed NiV RNA in oral swab specimens. We obtained surface swab samples for 6 Nipah patients; 5 had evidence of NiV RNA on >1 surface: 4 patients contaminated towels, 3 bed sheets, and 1 the bed rail. Patients with NiV RNA in oral swab samples were significantly more likely than other Nipah patients to die. To reduce the risk for fomite transmission of NiV, infection control should target hospital surfaces.

Preventing emergence of new zoonotic viruses depends on understanding determinants for human risk. Nipah virus (NiV) is a lethal zoonotic pathogen that has spilled over from bats into human populations, with limited person-to-person transmission. We examined ecologic and human behavioral drivers of geographic variation for risk of NiV infection in Bangladesh. We visited 60 villages during 2011–2013 where cases of infection with NiV were identified and 147 control villages. We compared case villages with control villages for most likely drivers for risk of infection, including number of bats, persons, and date palm sap trees, and human date palm sap consumption behavior. Case villages were similar to control villages in many ways, including number of bats, persons, and date palm sap trees, but had a higher proportion of households in which someone drank sap. Reducing human consumption of sap could reduce virus transmission and risk for emergence of a more highly transmissible NiV strain.

The behaviour of a torpedo anchor during dynamic installation in two-layered nonhomogeneous clay sediments was investigated through large-deformation finite-element (LDFE) analyses. Parametric analyses were undertaken varying the top layer thickness and strength ratio between two layers. Results show that the location of the demarcation point between the acceleration and deceleration phases of the anchor in the soil relative to the layer interface is the key factor directing the anchor behaviour in layered soils including the final embedment depth. Broadly speaking, the anchor behaviour in soft-over-stiff clay deposits is somewhat similar to that in single layer clay with strength increasing with depth. In stiff-over-soft clay deposits, the anchor penetrates deeper where the anchor deceleration phase (or the demarcation point) falls within the soft layer. Where the demarcation point lies within the top stiff layer, the anchor penetration depth decreases with increasing strength ratio, and the anchor penetration is terminated between the two layers for strength ratios [greater than or equal to] 15. For assessing the anchor embedment depth in two-layered fine-grained ocean sediments in the field, an extended total energy- based method, along with a design expression, is proposed. Key words: dynamically installed anchors, two-layered clays, dynamic installation, embedment depth, numerical modelling, offshore engineering. Le comportement d'un ancrage torpille pendant l'installation dynamique dans deux couches de sediments d'argile non homogene a ete etudie au moyen d'analyse de grandes deformations a elements finis (LDFE). Des analyses parametriques ont ete realisees variant l'epaisseur de la couche superieure et le rapport de la resistance entre deux couches. Les resultats montrent que l'emplacement du point de demarcation entre les phases d'acceleration et de deceleration de l'ancre dans le sol par rapport a la couche interface est le facteur cle faconnant le comportement d'ancrage dans des sols, dont la profondeur d'enfouissement definitif. En gros, le comportement d'ancrage dans des depots d'argile molle sur raide est quelque peu similaire a celle dans une seule couche d'argile avec la resistance augmentant avec la profondeur. Dans les depots d'argile raide sur molle, l'ancre penetre plus profondement, oU la phase de deceleration de l'ancre (ou le point de demarcation) releve de la couche molle. OU le point de demarcation se trouve dans la partie superieure de la couche rigide, la profondeur de penetration d'ancrage diminue avec l'augmentation du rapport de resistance, et la penetration de l'ancre est interrompue entre les deux couches pour des rapports de resistance [greater than or equal to] 15. Pour l'evaluation de la profondeur d'enfouissement d'ancrage en deux couches de sediments fins oceaniques sur les lieux, une methode basee sur l'energie totale etendue, avec un dessin d'expression, est proposee. [Traduit par la Redaction] Mots-cles : ancrages installes de facon dynamique, deux couches d'argiles, installation dynamique, profondeur d'enfouissement, modelisation numerique, ingenierie en mer., Introduction Dynamically installed anchors (DIAs) are the most recent type of anchoring solution providing a cost-effective alternative for mooring floating facilities in deep water clayey sediments. They are also being [...]

Nipah virus (NiV) is a batborne paramyxovirus (1,2) that causes encephalitis in humans. NiV has caused outbreaks almost every year in Bangladesh since 2001; the case-fatality rate is >70% (3).The [...]

Emerging zoonoses pose a substantial threat to human health and well-being (1). Some of the most devastating human disease pandemics have been caused by diseases originating in livestock or wildlife, [...]

Nipah virus (NiV) is a paramyxovirus, and Pteropus spp. bats are the natural reservoir. From December 2010 through March 2014, hospital-based encephalitis surveillance in Bangladesh identified 18 clusters of NiV infection. The source of infection for case-patients in 3 clusters in 2 districts was unknown. A team of epidemiologists and anthropologists investigated these 3 clusters comprising 14 case-patients, 8 of whom died. Among the 14 case-patients, 8 drank fermented date palm sap (tari) regularly before their illness, and 6 provided care to a person infected with NiV. The process of preparing date palm trees for tari production was similar to the process of collecting date palm sap for fresh consumption. Bat excreta was reportedly found inside pots used to make tari. These findings suggest that drinking tari is a potential pathway of NiV transmission. Interventions that prevent bat access to date palm sap might prevent tari-associated NiV infection.

Spudcan punch-through during installation and preloading process is one of the key concerns for the jack-up industry. This incident occurs in layered deposits, with new design approaches for spudcan penetration in sand-over-clay deposits reported recently. This paper reports a novel design approach for spudcan penetration in stiff-over-soft clay deposits. Largedeformation finite element (LDFE) analyses were carried out using the Coupled Eulerian-Lagrangian (CEL) approach. The clay was modelled using the extended elastic - perfectly plastic Tresca soil model allowing strain softening and rate dependency of the undrained shear strength. A detailed parametric study was undertaken, varying the strength ratio between bottom and top soil layers, the thickness of the top layer relative to the spudcan diameter, and degree of nonhomogeneity of the bottom layer. Existing data from centrifuge model tests were first used to validate the LDFE results, and then the measured and computed datasets were used to develop the formulas in the proposed design approach. The approach accounts for the soil plug in the bottom layer, and the corresponding additional resistance. Where there is the potential for punch-through, the approach provides estimations of the depth and bearing capacity at punch-through, the bearing capacity at the stiff-soft layer interface, and the bearing capacity in the bottom layer. Comparison shows that the punch-through method suggested in ISO standard 19905-1 provides a conservative estimate of the bearing capacity at punch-through, with guidelines provided to improve the method. Key words: bearing capacity, punch-through, clays, spudcan foundations, numerical modelling, offshore engineering. Le percage Spudcan lors du processus de l'installation et de prechargement est l'une des principales preoccupations pour l'industrie plate-forme de forage autoelevatrice. Cet incident se produit dans des depots en couches, avec de nouvelles approches de conception pour la penetration spudcan dans les depots argiles raides-sur- molles rapportes recemment. Cet article presente une nouvelle approche de conception pour la penetration spudcan dans des depots argiles raides-sur-molles. Des analyses de grande deformation a elements finis (LDFE) ont ete effectuees en utilisant l'approche couplee Eulerian- Lagrangien (CEL). L'argile a ete modelisee a l'aide du modele de sol Tresca plastique elastiquement parfaitement etendue permettant l'adoucissement et la dependance de taux de la resistance au cisaillement non draine. Une etude parametrique detaillee a ete realisee en faisant varier le rapport de resistance entre les couches de terre inferieure et superieure, l'epaisseur de la couche superieure par rapport au diametre du caisson de support et le degre de non-homogeneite de la couche inferieure. Les donnees existantes a partir d'essais de modeles de centrifugeuses ont ete d'abord utilisees pour valider les resultats de LDFE, puis les ensembles de donnees mesurees et calculees ont ete utilises pour developper les formules dans l'approche de conception proposee. L'approche represente la prise du sol dans la couche inferieure, et la resistance supplementaire correspondante. La ou ilyale potentiel de percage, l'approche fournit des estimations de la capacite de la profondeur et la portee au percage, la capacite portante a l'interface de la couche raide-molle, et la capacite portante dans la couche inferieure. La comparaison montre que la methode de percage suggeree dans lanormelSO 19905-1 fournit une estimation prudente de la capacite portante aupercage, avec les lignes directrices fournies pour ameliorer la methode. [Traduit par la Redaction] Mots-cles: capacite portante, percage, argiles, caissons de fondation, modelisation numerique, ingenierie en mer., Introduction Spudcan foundation and punch-through Most offshore drilling in shallow to moderate water depths is performed from self-elevating jack-up rigs owing to their proven flexibility, mobility, and cost effectiveness (CLAROM1993; [...]