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Optimizing community-based fisheries management to enhance both food resource and biodiversity conservation in large lakes requires detailed knowledge of benthic habitats, which determines suitability for fish breeding sites. This information is unavailable for much of Lake Tanganyika, whose fisheries are threatened by a warming climate, destructive harvesting practices, and sediment pollution. Lake Tanganyika possesses a remarkably diverse fish population. Much of this is concentrated in areas with water depths less than 30 m and on rocky substrate. Here, geophysical tools were used to map benthic habitats in a 21 km2 co-management area of the lake in western Tanzania. Echosounding defined the position of the 30-m isobath, which varies with proximity to deltas and rift-related faults. Side-scan sonar discriminated among four unique substrates: crystalline bedrock, calcite-cemented sandstones, mixed siliciclastic sediments, and shell-rich sediments. Unlithified mixed silts and sands constitute over 91% of the study area. Rocky substrate composed of crystalline basement and calcite-cemented sandstone make up the less than 9% of the substrate in the study area. Crystalline bedrock was present from 0 to 30 m water depth, whereas the calcite-cemented sandstones were encountered in water less than 5 m deep. The spatial organization of rocky substrates is interpreted to be controlled by basin structure and lake level history; these habitats make ideal targets for establishing new small-scale protected areas. The techniques illustrated in this study are broadly applicable elsewhere in Lake Tanganyika, and to other large lakes where data needs for placing conservation reserves are lacking. [ABSTRACT FROM AUTHOR]

Objectives: To examine the impact of Australia's single dose infant varicella vaccination program, we assessed single dose varicella vaccine effectiveness (VE) in preventing hospitalised disease using two methods.Methods: Clinically confirmed varicella cases from the Paediatric Active Enhanced Disease Surveillance (PAEDS) sentinel network were age-matched to 20 controls obtained from the Australian Immunisation Register. Conditional logistic regression models were used to estimate VE and compared with estimates obtained using our second approach.Results: There were 78 hospitalised varicella cases during the post vaccine introduction period from January 2008 to December 2015, who were eligible for funded varicella vaccination. Median age at onset was 4.5 years and more than half (59%) were vaccinated. The majority of children received one vaccine brand (Varilrix, GSK). The estimated case-control VE for one dose of vaccine against hospitalised varicella was 64.7% (95% CI: 43.3-78.0%); estimates using the screening method were not significantly different. Exclusion of children who were immunocompromised did not significantly alter VE estimates.Conclusions: Although Australia's program has impacted on the burden of varicella disease, single dose VE against varicella hospitalisation is only moderate. Greater reductions in varicella disease could potentially be achieved by incorporation of a second vaccine dose into the program to minimise breakthrough disease and interrupt virus circulation. [ABSTRACT FROM AUTHOR]

Improving understanding of how biodiversity and ecosystems respond to environmental change is necessary to guide policy and management. To this end, the bioDISCOVERY project of the international programme on global change, Future Earth, initiates and supports international networks of scientists to advance research on monitoring and observations, scenarios and models, and assessments of biodiversity and ecosystems. bioDISCOVERY activities seek collective solutions to key research challenges, and provide support for the international science community by participating in the development of global databases. This global working-group approach is essential for directing cutting-edge science toward supporting international policies, addressing urgent environmental issues, and closing research gaps through transdisciplinary integration and mobilisation of the scientific community. [ABSTRACT FROM AUTHOR]

Objectives: Changes in circulating Bordetella pertussis genotypes, including a novel pertussis toxin promoter ptxP3 allele and absence of pertactin (Prn) antigen, have been reported from several countries but limited data on relative severity are available. We compared markers of disease severity in children with B. pertussis infection due to strains of differing genotype.Methods: Culture confirmed cases presenting to tertiary paediatric hospitals in three Australian states between 2008 and 2012 were classified as severe if they required a hospital stay greater than seven days, were admitted to intensive care, or if death occurred. Associations between age, vaccination, genotype and severity were assessed.Results: Of 199 pertussis cases, 81 (41%) were <3 months, including 32/39 (82%) of severe cases. The proportion of isolates from these cases that were Prn deficient increased markedly between 2008 and 2012. Of B. pertussis isolates, the proportion considered severe was similar for Prn positive (27/128, 21%) and Prn deficient (12/71, 17%) cases but only 1/22 (4.5%) of non ptxP3 cases were severe versus 38/177 (21.4%) ptxP3 positive. Adjusting for ptxP type, vaccination status and age, disease severity was not significantly associated with Prn status (RRA: 0.95, [0.57-1.56]; p = 0.83).Conclusions: In children, we found no relationship between Prn status and markers of severe pertussis. An increased proportion of severe disease in isolates with the ptxP3 allele was observed. [ABSTRACT FROM AUTHOR]

Landscape alterations can obstruct movement corridors and degrade spawning habitats for migratory fishes, requiring expensive restoration efforts. To assess use of natural and artificial waterways for spawning migrations, we monitored adult migrations and young-of-year production of northern pike ( Esox lucius ) for two years in six adjacent tributaries of southern Green Bay on Lake Michigan, USA. Field observations were compared with natal origins of young-of-year and adults inferred from otolith microchemistry. Individual tributaries varied widely in their production of young-of-year pike. Microchemical differences were apparent only among tributaries whose watersheds differ in land use, and adult pike showed no evidence of homing even to the same tributary land use class where they were born. Though otolith microchemistry suggests a lack of fidelity to natal streams, carbon stable isotope ratios of adult pike showed a latitudinal gradient across tributaries, suggesting that adult pike do not mix freely outside of the breeding season. Both field observations and microchemical tracing suggest that pike can potentially recolonize historical or newly-created breeding habitats after restoration efforts make them accessible. [ABSTRACT FROM AUTHOR]

Hydropower continues to expand globally as the power sector transitions away from carbon-intensive fossil fuels. New dam sites vary widely in the magnitude of their adverse effects on natural ecosystems and human livelihoods. Here, we discuss how strategic planning of hydropower expansion can assist decision makers in comparing the benefits of building dams against their socioenvironmental impacts. Advances in data availability and computational analysis now enable accounting for an increasing array of social and environmental metrics at ever-larger spatial scales. In turn, expanding the spatial scale of planning yields more options in the quest to improve both economic and socioenvironmental outcomes. There remains a pressing need to incorporate climate change into hydropower planning. Ultimately, these innovations in evaluating prospective dam sites should be integrated into strategic planning of the entire energy system to ensure that social and environmental disruption of river systems is minimized. [ABSTRACT FROM AUTHOR]

Abstract: Allochthonous nutrients and carbon are recognized as dominant controls on biogeochemistry of low-order streams. In some systems, potamodromous fish may provide a complementary source of material as they deliver lake-derived materials to spawning streams. This study examines nutrient and carbon inputs from terrestrial ecosystems and migratory fishes to streams in undeveloped watersheds in northern Michigan, USA. We compared watershed and riparian area, slope, and landcover to nutrient concentrations at 26 sites, as well as whole-stream metabolism at 5 sites. Despite low levels of agricultural land use (0–3%), agriculture had the largest influence on stream chemistry as indicated by higher dissolved organic carbon (DOC), ammonium, silica, and chloride concentrations at the watershed level, and increased DOC and chloride at the riparian level. Ecosystem respiration and net primary production increased with watershed and riparian area, and the proportion of managed forest. To quantify inputs from fish, we monitored the spawning migrations of white (Catostomus commersonii) and longnose (C. catostomus) suckers at one site, and measured nutrients and stream metabolism above and below an impassable dam. Nutrient concentrations were uniformly low and did not increase during the fish migration; however, temporal shifts in stream metabolism during sucker migration suggest that fish influenced respiration, presumably by providing high-quality carbon and bioavailable nutrients. We conclude that both watershed land use and fish migrations provide important sources of allochthonous material to these oligotrophic streams. Recognizing the bi-directional nature of allochthonous inputs is important for understanding controls on ecosystem functioning in low-order streams. [Copyright &y& Elsevier]

• Water security threats and loss of natural capital rise rapidly across the century. • Societal response features a major expansion of traditional engineering. • Contributions of natural capital to water security exceed investments in engineering. • Degraded ecosystems incur a substantial economic penalty on water resource systems. • A transformation to sustainable green-gray water infrastructure is globally feasible. Sustainable development demands reliable water resources, yet traditional water management has broadly failed to avoid environmental degradation and contain infrastructure costs. We explore the global-scale feasibility of combining natural capital with engineering-based (green-gray) approaches to meet water security threats over the 21st century. Threats to water resource systems are projected to rise throughout this period, together with a significant expansion in engineering deployments and progressive loss of natural capital. In many parts of the world, strong path dependencies are projected to arise from the legacy of prior environmental degradation that constrains future water management to a heavy reliance on engineering-based approaches. Elsewhere, retaining existing stocks of natural capital creates opportunities to employ blended green-gray water infrastructure. By 2050, annual engineering expenditures are projected to triple to $2.3 trillion, invested mainly in developing economies. In contrast, preserving natural capital for threat suppression represents a potential $3.0 trillion in avoided replacement costs by mid-century. Society pays a premium whenever these nature-based assets are lost, as the engineering costs necessary to achieve an equivalent level of threat management are, on average, twice as expensive. Countries projected to rapidly expand their engineering investments while losing natural capital will be most constrained in realizing green-gray water management. The situation is expected to be most restrictive across the developing world, where the economic, technical, and governance capacities to overcome such challenges remain limited. Our results demonstrate that policies that support blended green-gray approaches offer a pathway to future global water security but will require a strategic commitment to preserving natural capital. Absent such stewardship, the costs of water resource infrastructure and services will likely rise substantially and frustrate efforts to attain universal and sustainable water security. [ABSTRACT FROM AUTHOR]

• The CFLRP is generating collaborative benefits suggesting that this policy has been effective at facilitating collaboration. • The efficacy of the CFLRP is likely a result of a policy framework that affords stability and legitimacy while providing space for flexibility and adaptation at the local level.. • We found evidence of second-order outcomes under the CFLRP, such as increased pace and scale of restoration, the diffusion of practice beyond project boundaries, and leveraging of resources. • While the mandate to collaborate helped formalize collaboration on projects, ultimately, there needed to be a level of informal collaboration in-place before project selection. Collaborative governance and landscape approaches have become a more prevalent in public land management in the United States in the face of increasing ecological and societal complexity and decreasing government resources and capacity. In this era of devolution and social-ecological change, there is a growing need for policy approaches that facilitate partnerships and participatory approaches to land management. One unique policy that emphasizes collaboration and large-landscape restoration on US federal forestlands is the Collaborative Forest Landscape Restoration Program (CFLRP), established in 2009 to accelerate the pace and scale of forest restoration. The policy included novel characteristics such as a decade-long commitment to landscapes and formal requirements for collaboration. This program presented an opportunity to assess how this policy affected collaboration and the factors that led to differential policy implementation. We conducted 89 interviews across all 23 CFLRP projects with internal agency staff and external collaborators on each project. We found that the CFLRP generated a variety of benefits related to collaboration, including increased trust and stronger relationships, increased collaborative partner influence, decreased litigation and conflict, and increased capacity to accomplish work; however, there were also challenges associated with the program, including thetime-intensive nature of collaboration and the lack of industry or contractors. Various local factors affected collaborative outcomes under the policy, including staff turnover and capacity, local leadership, and collaborative history. Successful collaborative outcomes were widespread under the CFLRP, and from this, we draw implications for the broader environmental governance literature about the policy characteristics that facilitate collaboration and the other institutional variables that may require attention in this context. [ABSTRACT FROM AUTHOR]

Objective: To assess changes in diagnostic practice and vaccine schedules for pertussis, we used culture-confirmation and clinical severity to compare pertussis cases at a single Australian tertiary pediatric hospital during relevant periods.Study Design: We replicated the case ascertainment methods of a study reporting a 2-year epidemic period 1997-1999 (whole cell pertussis vaccine with 18-month booster, only culture available) to conduct a retrospective cross-sectional observational study over a 6-year period 2007-2012 (acellular pertussis vaccine, no 18-month booster, polymerase chain reaction and culture available). Cases were compared from case note review 2007-2012 (including prevalence of comorbidities) and published data 1997-1999.Results: During 2007-2012, average annual hospitalizations in those aged < 6 months increased 2.3-fold (32.0 vs 14.0) and in those aged > 6 months by 5.1-fold (17.7 vs 3.5). Limited to culture-positive hospitalizations, there was no increase in those aged < 6 months (14.0 vs 14.5) contrasted with a 4.6-fold increase in those aged > 6 months (2.3 vs 0.5), despite increased annual culture requests (488 vs 188). In 2007-2012, significant comorbidities were documented in 41/72 (57%) hospitalized children aged ≥ 12 months vs 38/225 (17%) <12 months (OR 6.5, 95% CI 3.7-11.7).Conclusions: Increased cases of culture-positive hospitalized pertussis were limited to fully immunized children > 6 months of age, consistent with schedule changes. Significant comorbidities were common, making a booster dose at 12-18 months of age especially important. [ABSTRACT FROM AUTHOR]

Clin Microbiol Infect 2010; 16: 948–954 The present study describes the clinical and immunological features of children with Hib vaccine failure, who were identified through national surveillance between 1996 and 2001 in Europe, Israel and Australia. True vaccine failure was defined as invasive Hib disease occurring ≥2 weeks after one dose, given after the first birthday, or ≥1 week after ≥2 doses, given at <1 year of age. Of the 423 cases (representing 0.2 cases per 100 000 child-years at risk) reported, 330 (78%) had received three doses in the first year of life and developed disease at a median age of 28 months. Of the remaining 93, 48 had received two doses in infancy, 34 had received four doses including a booster, and 11 had received a single dose after 12 months of age. These children developed disease at a median age of 12, 33 and 71 months, respectively. In total, 47 out of 258 children (18%) with available information had an underlying medical problem (including prematurity) and 53 out of 161 (33%) had immunoglobulin deficiency. Convalescent Hib antibody concentrations were above the putative protective concentration of 1.0 mg/L in 147/194 (76%) children; low concentrations were associated with both the presence of an underlying medical problem and young age at the time of Hib disease. Almost all children who received an additional vaccine dose developed antibodies at protective concentrations. Thus, Hib vaccine failure is rare, but can occur with any immunization schedule. Children with Hib vaccine failure should have immunoglobulin and convalescent Hib antibody concentrations measured after infection and receive additional vaccination, if required. [ABSTRACT FROM AUTHOR]

Presents a study that determined the impact of the Australian Measles Control Campaign (MCC) on the transmission dynamics of measles by calculating the reproductive number before and after the MCC. Methodology; Results and discussion.