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Reported mpox cases in England continued at a low but steady frequency during 2023. Of 137 cases reported in 2023, approximately half were acquired overseas and half were in vaccinated persons. Estimated effectiveness of 2-dose vaccine was 80%, and no vaccinated mpox patient was hospitalized.

Abstract Shigellosis is an enteric infection that transmits through the faecal-oral route, which can occur during sex between men who have sex with men (MSM). Between 2009 and 2014, an epidemic of sexually transmissible Shigella flexneri 3a occurred in England that subsequently declined. However, from 2019 to 2021, despite SARS-CoV-2 restrictions, S. flexneri 3a continued to re-emerge. We explored possible drivers of re-emergence by comparing host demography and pathogen genomics. Cases were primarily among 35–64 year old men in London. Genomic analyses of 502 bacterial isolates showed that the majority (58%) of re-emerging MSM strains were a clonal replacement of the original, with reduced antimicrobial resistance, conservation of plasmid col156_1, and two SNPs with 19 predicted effects. The absence of major changes in the pathogen or host demographics suggest that other factors may have driven the re-emergence of S. flexneri 3a and highlight the need for further work in the area.

After lifting of all COVID-19 preventive measures in England in July 2021, marked, widespread increases in gonorrhea diagnoses, but not testing numbers, were observed, particularly in persons 15–24 years of age. Continued close surveillance and public health messaging to young persons are needed to control and prevent gonorrhea transmission.

After community transmission of monkeypox virus was identified in Europe, interviews of 45 case-patients from England indicated transmission in international sexual networks of gay and bisexual men since April 2022. Interventions targeting sex-on-premises venues, geospatial dating applications, and sexual health services are likely to be critical for outbreak control.

Incidence of lymphogranuloma venereum increased in England during 2018–2019, after a period of decline. Our retrospective analysis of national surveillance data identified a rapid increase in diagnoses among HIV-negative men who have sex with men. These findings indicate a need for sustained surveillance and targeted public health action.

Waves and tidal currents can interact to produce strong seabed shear stress and mobilization of sediments on continental shelves. Modelled wave and tidal current data for a 3-year period were used in a combined-flow sediment transport model to simulate the seabed shear stresses and the mobilization of uniform medium sand on the continental shelves of Canada. The modelling results are presented to establish the first national framework of seabed disturbance and sediment mobility on the continental shelves of Canada. Strong waves and tidal currents on the Canadian continental shelves produce mean bed shear velocity >5 cm * [s.sup.-1]. Medium sand can be mobilized >50% of the time over many areas on the shelves. The mobilization by tidal currents occurs over 36% and by waves over 50% of the shelf area, demonstrating that mobilization of sediments is dominated by waves on the Canadian continental shelves. Combined shear stresses due to wave and tidal current interaction further increase sediment mobilization to over 68% of the shelf area. The spatial variation of the relative importance of wave and tidal disturbances allows classification of the continental shelves into six disturbance types. Innovative Seabed Disturbance (SDI) and Sediment Mobility (SMI) indices are proposed to quantify the seabed exposure to oceanographic processes and sediment mobilization, incorporating both the magnitude and frequency of these processes. The proposed SDI and SMI, together with the disturbance type classification, can be used as standard parameters to best quantify seabed disturbance and sediment mobility on other shelves of the world. Key words: tidal current and waves, shear stresses, sediment mobilization, seabed disturbance, continental shelves, Canada. Les vagues et courants de maree peuvent interagir pour produire de fortes contraintes de cisaillement sur le fond marin et la mobilisation de sediments sur les plateaux continentaux. Des donnees modelisees sur les vagues et les courants de maree pour une periode de trois ans ont ete utilisees dans un modele de transport de sediments a ecoulement combine pour simuler les contraintes de cisaillement sur le fond marin et la mobilisation de sable moyen uniforme sur les plateaux continentaux du Canada. Les resultats de la modelisation sont presentes dans le but d'etablir le premier cadre national de perturbations du fond marin et de mobilite des sediments sur les plateaux continentaux du Canada. De forts courants de maree et vagues sur les plateaux continentaux canadiens produisent des vitesses de cisaillement moyennes sur le fond de >5 cm * [s.sup.-1]. Le sable moyen peut etre mobilise >50 % du temps sur de nombreux secteurs des plateaux. La mobilisation par des courants de maree se produit sur plus de 36 %, et par les vagues, sur plus de 50 % de la superficie des plateaux, ce qui demontre que les vagues constituent l'agent dominant de mobilisation de sediments sur les plateaux continentaux canadiens. Les contraintes de cisaillement combinees dues a l'interaction des vagues et des courants de maree accroissent egalement la mobilisation de sediments sur 68 % de la superficie des plateaux. Les variations spatiales de l'importance relative des perturbations par les vagues et les marees permettent la categorisation des plateaux continentaux selon six types de perturbations. Des indices novateurs de perturbation du fond marin (SDI) et de mobilite des sediments (SMI) sont proposes pour quantifier l'exposition des fonds marins a des processus oceanographiques et a la mobilisation de sediments, incorporant a la fois la magnitude et la frequence de ces processus. Les indices proposes, combines a la categorisation des types de perturbations, peuvent etre utilises comme parametres normalises pour quantifier le mieux les perturbations du fond marin et la mobilite des sediments sur d'autres plateaux du monde. [Traduit par la Redaction] Mots-cles : courant de maree et vagues, contraintes de cisaillement, mobilisation de sediments, perturbation du fond marin, plateaux continentaux, Canada., Introduction The impacts on the seafloor exerted by waves and currents, and the sediment responses to this forcing, directly affect the cost and safety of seabed installations for offshore engineering [...]

Oxygen is declining globally in subsurface seawater. Fjords are particularly susceptible to hypoxia, because entrance sills restrict water circulation. We studied the oxygen dynamics of the Kitimat Fjord System on the west coast of Canada, using 3 yr of data from moored sensors and water column profiles. Subsurface oxygen within the fjord system is principally controlled by the connection to Hecate Strait on the outer shelf. Variations in oxygen concentration in Hecate Strait are reflected in the water that is drawn into the fjord system year‐round at mid‐depth (50–150 m). Deep water is renewed annually, beginning in May/June. Remineralization results in a seasonal decline in oxygen at depth. In the absence of deep‐water renewal, the bottom water in the system could become hypoxic in 1–2 yr. Mixing over a shallow inner sill (100 m) replenishes the oxygen in the deep water of Gardner Canal year‐round. The decadal trends in oxygen concentration show an increase from the 1950s to a maximum in the late 1970s, followed by a decline through 2016. The decline over the period 1977–2016 is 0.018 mL L−1 yr−1 (~ 0.83 μmol L−1 yr−1), which is consistent with the decline observed over the upper continental shelf over the same period. [ABSTRACT FROM AUTHOR]

Information about seabed stability and sediment dynamics is part of the fundamental geoscience knowledge required for the extraction of tidal energy in the Bay of Fundy and for the integrated management of the Bay. Waves, tidal currents, and wind-driven and circulation currents were obtained from oceanographic models to assess the wave and current processes for the broader Bay of Fundy. The wave and current outputs were coupled with observed grain size in a sediment transport model to predict, for the first time, the seabed shear stresses, sediment mobility, and sediment transport patterns for the entire Bay. The root mean square tidal current, highest in the upper Bay (>1.4 m x [s.sup.-1]), is reduced to moderate in the central Bay (0.50.8 m x [s.sup.-1]) and decreases further in the outer Bay (0.2-0.5 m x [s.sup.-1]). The maximum tidal current occurs in the Minas Passage and is >5 m x [s.sup.-1]. The mean significant wave height, in contrast, is the greatest in the outer Bay (~1.3 m) and gradually decreases to the northeast in the central and upper Bay (30% of the time over most of the Bay and reaches 100% of the time in some areas. The maximum total-load sediment transport rate under spring tide can reach ~5 kgx[m.sup.-1] x [s.sup.-1] and is to the northeast during flood and to the southwest during ebb. Net sediment transport flux, however, is dominantly to the northeast and reaches 2 kg x [m.sup.-1] x [s.sup.-1]. Eddies of net transport are found to occur around headlands and at the narrows of Grand Manan Island, largely due to the occurrence of eddies of residual tidal flows. The regional distribution of substrate types and bedform fields and patterns of seabed erosion and deposition are well correlated with tidal current strength and sediment transport patterns. Des donnees concernant la stabilite du plancher oceanique et la dynamique des sediments constituent une partie fondamentale des connaissances geologiques requises pour l'extraction de l'energie maremotrice dans la baie de Fundy et pour une gestion integree de la baie. Les vagues, les courants de maree, les courants pousses par les vents et les courants de circulation ont ete obtenus de modeles oceanographiques afin d'evaluer les processus des vagues et des courants pour l'ensemble de la baie de Fundy. Les donnees de sortie sur les vagues et les courants ont ete jumelees aux granulometries observees dans un modele de transport de sediments afin de predire, pour la premiere fois, les contraintes de cisaillement sur le plancher oceanique, la mobilite des sediments et les patrons de transport pour toute la baie. Le courant de maree moyen quadratique, plus eleve dans le fond de la baie (>1,4 m x [s.sup.-1]), est reduit a modere dans le centre de la baie (0,5-0,8 m x [s.sup.-1]) et il decroit en encore plus au large de la baie (0,2-0,5 m x [s.sup.-1]). Le courant de maree maximal se trouve dans le Passage Minas, ou il est >5 m x [s.sup.-1]. La hauteur significative moyenne de vague est par contre la plus elevee au large de la baie (~1,3 m) et elle decroit ensuite vers le nord-est dans la partie centrale et dans le fond de la baie (30 % du temps a travers la plus grande partie de la baie et elle atteint meme 100 % du temps dans certains secteurs. Le taux maximal de transport de la charge totale des sediments peut atteindre ~5kg x [m.sup.-1]x[s.sup.-1]lors des marees de printemps et cela se produit vers le nord-est durant la maree montante et vers le sud-ouest durant la maree descendante. Le flux net de transport des sediments est toutefois dominant vers le nord-est ou il atteint 2 kg x [m.sup.-1]x[s.sup.-1]. Des contre-courants de transport net se retrouvent autour des promontoires et au passage de l'ile de Grand Manan, grandement en raison de l'occurrence de contre-courants de debits de maree residuels. La distribution regionale des types de substrat et des morphologies de fond ainsi que les patrons d'erosion du plancher oceanique et de deposition sont bien correles avec la force des courants de maree et les patrons de transport des sediments. [Traduit par la Redaction], Introduction The Bay of Fundy, located on the east coast of Canada (Fig. 1), has been of great economic, ecological, and scientific significance because of its world-renowned tides, unique seabed [...]

Douglas Channel is the principal shipping route between the town of Kitimat and the Pacific Ocean. Prediction of near-surface currents is crucial for safe tanker navigation and cleaning-up oil spills. Three years of current velocity data were collected at two moorings located 30 km apart. Spectral, wavelet, and harmonic analysis of measured currents throughout the upper (40-m) and lower (50–358 m) water columns indicated the predominant influence of semidiurnal (SD) tidal currents. In the upper layer, wind and density flows resulted in considerable seasonal and interannual variability of these currents. Analysis of the SD variance reveals three major components: barotropic, coherent baroclinic, and random baroclinic. The predictability of near-surface currents depends on the relative contribution and stability of the first two components. Tidal constants estimated for one year were used to predict currents for two other years; we found that at the mooring closer to the entrance of Douglas Channel, 80 to 89% of the SD energy in the upper layer and 89–93% in the lower layer can be forecasted, while closer to the two channel head, these numbers are smaller: 55–70% and 79–89%, respectively. [ABSTRACT FROM AUTHOR]