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Background: Murray Valley encephalitis virus (MVEV) is a clinically important virus in Australia responsible for a number of epidemics over the past century. Since there is no vaccine for MVEV, other preventive health measures to curtail its spread must be considered, including the development of predictive risk models and maps to help direct public health interventions. This article aims to support these approaches by presenting a model for assessing MVEV risk in Western Australia (WA). Methods: A Bayesian Belief Network (BBN) for assessing MVEV risk was developed and used to quantify and map disease risks in WA. The model combined various abiotic, biotic, and anthropogenic factors that might affect the risk of MVEV into a predictive framework, based on the ecology of the major mosquito vector and waterbird hosts of MVEV. It was further refined and tested using retrospective climate data from 4 years (2000, 2003, 2009, and 2011). Results: Implementing the model across WA demonstrated that it could predict locations of human MVEV infection and sentinel animal seroconversion in the 4 years tested with some degree of accuracy. In general, risks are highest in the State's north and lower in the south. The model predicted that short-term climate change, based on the Intergovernmental Panel on Climate Change's A1B emissions scenario, would decrease MVEV risks in summer and autumn, largely due to higher temperatures decreasing vector survival. Conclusions: To our knowledge, this is the first model to use a BBN to quantify MVEV risks in WA. The models and maps developed here may assist public health agencies in preparing for and managing Murray Valley encephalitis in the future. In its current form, the model is knowledge-driven and based on the analysis of potential risk factors that affect the dynamics of MVEV using retrospective data. Further work and additional testing should be carried out to test its validity in future years. [ABSTRACT FROM AUTHOR]

From Resource Scarcity to Ecological Security: Exploring New Limits to Growth Edited by Dennis Pirages and Ken Cousins Cambridge, MA:MIT Press, 2005. 268 pp. ISBN: 0-262-16231-8, $60 In the face [...]

Background: There are many communities around the world that are exposed to high levels of particulate matter <10 µm (PM10) of geogenic (earth derived) origin. Mineral dusts in the occupational setting are associated with poor lung health, however very little is known about the impact of heterogeneous community derived particles. We have preliminary evidence to suggest that the concentration of iron (Fe) may be associated with the lung inflammatory response to geogenic PM10. We aimed to determine which physico-chemical characteristics of community sampled geogenic PM10 are associated with adverse lung responses. Methods: We collected geogenic PM10 from four towns in the arid regions of Western Australia. Adult female BALB/c mice were exposed to 100 µg of particles and assessed for inflammatory and lung function responses 6 hours, 24 hours and 7 days post-exposure. We assessed the physico-chemical characteristics of the particles and correlated these with lung outcomes in the mice using principal components analysis and multivariate linear regression. Results: Geogenic particles induced an acute inflammatory response that peaked 6 hours post-exposure and a deficit in lung mechanics 7 days post-exposure. This deficit in lung mechanics was positively associated with the concentration of Fe and particle size variability and inversely associated with the concentration of Si. Conclusions: The lung response to geogenic PM10 is complex and highly dependent on the physico-chemical characteristics of the particles. In particular, the concentration of Fe in the particles may be a key indicator of the potential population health consequences for inhaling geogenic PM10. [ABSTRACT FROM AUTHOR]

Abstract: Our hypothesis is that symptoms of high altitude syndromes are detectable even at intermediate altitudes, as commonly encountered under Australian conditions (<2500m above sea level). High altitude medicine has long recognised several syndromes associated with rapid ascent to altitudes above 2500m, including high altitude pulmonary oedema (HAPE), high altitude cerebral oedema (HACE) and high altitude flatus expulsion (HAFE). Symptoms of high altitude syndromes are of growing concern because of the global trend toward increasing numbers of tourists and workers exposed to both rapid ascent and sustained physical activity at high altitude. However, in Australia, high altitude medicine has almost no profile because of our relatively low altitudes by international standards. Three factors lead us to believe that altitude sickness in Australia deserves more serious consideration: Australia is subject to rapid growth in alpine recreational industries; altitude sickness is highly variable between individuals, and some people do experience symptoms already at 1500m; and there is potential for an occupational health and safety issue amongst workers. To test this hypothesis we examined the relationship between any high altitude symptoms and a rapid ascent to an intermediate altitude (1800m) by undertaking an intervention study in a cohort of eight medical clinic staff, conducted during July of the 2012 (Southern Hemisphere) ski season, using self-reporting questionnaires, at Mansfield (316m above sea level) and at the Ski Resort of Mt Buller (1800m), Victoria, Australia. The intervention consisted of ascent by car from Mansfield to Mt Buller (approx. 40min drive). Participants completed a self-reporting questionnaire including demographic data and information on frequency of normal homeostatic processes (fluid intake and output, food intake and output, symptoms including thirst and headaches, and frequency of passing wind or urine). Data were recorded in hourly periods extending over 18h before and 18h after ascent. We found that the frequency of flatus production more than doubled following ascent, with a post-ascent frequency of approximately 14 expulsions per person over the 18h recording period (Rate Ratio 2.31, CI 1.33–3.99, p =0.003). The frequency and severity of headaches also increased following ascent. These results support the hypothesis that high altitude symptoms can be significant issues even at the relatively lower altitudes encountered in Australian alpine regions. Increased awareness amongst clinicians of this possibility could contribute to a reduction in the disease burden from high altitude syndromes at intermediate altitudes. [Copyright &y& Elsevier]

Background: Pre-eclampsia is a common complication of pregnancy and is a major cause of fetal-maternal mortality and morbidity. Despite a number of plausible mechanisms by which air pollutants might contribute to this process, few studies have investigated the association between pre-eclampsia and traffic emissions, a major contributor to air pollution in urban areas. Objective: The authors investigated the association between traffic-related air pollution and risk of preeclampsia in a maternal population in the urban centre of Perth, Western Australia. Method: The authors estimated maternal residential exposure to a marker for traffic-related air pollution (nitrogen dioxide, NO2) during pregnancy for 23 452 births using temporally adjusted land-use regression. Logistic regression was used to investigate associations with pre-eclampsia. Results: Each IQR increase in levels of traffic-related air pollution in whole pregnancy and third trimester was associated with a 12% (1%--25%) and 30% (7%--58%) increased risk of pre-eclampsia, respectively. The largest effect sizes were observed for women aged younger than 20 years or 40 years or older, aboriginal women and women with pre-existing and gestational diabetes, for whom an IQR increase in traffic-related air pollution in whole pregnancy was associated with a 34% (5%--72%), 35% (0%--82%) and 53% (7%--219%) increase in risk of pre-eclampsia, respectively. Conclusions: Elevated exposure to traffic-related air pollution in pregnancy was associated with increased risk of pre-eclampsia. Effect sizes were highest for elevated exposures in third trimester and among younger and older women, aboriginal women and women with diabetes. [ABSTRACT FROM AUTHOR]

Background Fetal growth restriction has been inconsistently associated with maternal exposure to elevated levels of traffic-related air pollution. Objective We investigated the relationship between an individualised measure of fetal growth and maternal exposure to a specific marker for traffic-related air pollution. Methods We estimated maternal residential exposure to a marker for traffic-related air pollution (nitrogen dioxide, NO2) during pregnancy for 23 452 births using temporally adjusted land-use regression. Logistic regression was used to investigate associations with small for gestational age and sex (SGA) and fetal growth restriction, defined as proportion of optimal birth weight (POBW) below the 10th percentile. Sub-populations investigated were: women who spent most time at home, women who did not move house, women with respiratory or circulatory morbidity, women living in low/ middle/high socio-economic areas, women who delivered before 37 weeks gestation, and women who delivered from 37 weeks gestation. Results An IQR increase in traffic-related air pollution in the second trimester across all women was associated with an OR of 1.31 (95% CI 1.07 to 1.60) for fetal growth restriction. Effects on fetal growth restriction (low POBW) were highest among women who subsequently delivered before 37 weeks of gestation. Effects on SGA were highest among women who did not move house: OR 1.35 (95% CI 1.08 to 1.69). Conclusions Larger effect sizes were observed for low POBW than for SGA. Exposure to traffic-related air pollution in mid to late pregnancy was associated with risk of SGA and low POBW in this study. [ABSTRACT FROM AUTHOR]

Abstract: The adverse environmental outcomes of disturbing acid sulfate soils have long been known, and there is a general consensus that avoiding disturbance is the most cost-efficient solution. However, canal estates are increasing in popularity on the west coast of Australia, in spite of a large proportion of the country''s acid sulfate soils being located along its coast. This study examined the mobility and concentration of metals in surface soil, dust and water sampled from one of the earliest canal developments in Western Australia. Soil metal concentrations were significantly elevated compared to an undisturbed reference site. While the dust fraction generally held higher metal concentrations in the original soil of the area, the total metal load was higher in the dredged and deposited material. None of the samples were above guideline values. The surface water of the canals had concentrations of iron and arsenic above the Australian drinking water guideline value while nickel concentrations were above the ecological guideline value. The pH of the water was not affected. The human health consequences of these findings may not be severe as the water is not used for drinking. However, the results highlight the need for transparency in the land development process, where developers are responsible for informing home buyers of the consequences related to developing acid sulfate soil areas and the steps that are being taken towards remediation or avoidance. Moreover, the results show the importance of monitoring metal concentrations in addition to pH in waters potentially affected by acid sulfate soils. [Copyright &y& Elsevier]

Abstract: Australia is currently experiencing a process of escalating ecosystem degradation. This landscape degradation is associated with many outcomes that may directly or indirectly impact on human health. This study used a Bayesian spatial method to examine the effects of environmental degradation (measured as dryland salinity) on the mental health of the resident rural population. An association was detected between dryland salinity and depression, indicating that environmental processes may be driving the degree of psychological ill-health in these populations. [Copyright &y& Elsevier]

Bushfire smoke contains an array of organic and inorganic compounds, including respirable and inspirable particles, aldehydes, and carbon monoxide. These compounds have been found to be a health hazard for firefighters in the United States. Despite the high frequency of bushfires in Australia, analyses of bushfire smoke components are scarce. As part of an occupational health study investigating the respiratory health effects of bushfire smoke in firefighters, air toxics sampling was undertaken in a smoke chamber and during prescribed burns. Levels of formaldehyde and acrolein were demonstrated at respectively 60% and 80% of the Short Term Exposure Limit in the smoke chamber. Carbon monoxide levels exceeded the peak limit of 400 ppm significantly. Although concentrations were lower during the prescribed burns, the study shows that Australian bushfire smoke contains air toxics of concern and provides justification for further research into the levels of air toxics measured at bushfires and the associated health impacts. [ABSTRACT FROM AUTHOR]

BACKGROUND: By international standards, water supplies in Perth, Western Australia, contain high trihalomethane (THM) levels, particularly the brominated forms. Geographic variability in these levels provided an opportunity to examine cross-city spatial relationships between THM exposure and rates of birth defects (BDs). OBJECTIVES: Our goal was to examine BD rates by exposure to THMs with a highly brominated fraction in metropolitan locations in Perth, Western Australia. METHODS: We collected water samples from 47 separate locations and analyzed them for total and individual THM concentrations (micrograms per liter), including separation into brominated forms. We classified collection areas by total THM (TTHM) concentration: low (< 60 µg/L), medium (> 60 to < 130 µg/L), and high (≥ 130 µg/L). We also obtained deidentified registry-based data on total births and BDs (2000-2004 inclusive) from post codes corresponding to water sample collection sites and used binomial logistic regression to compare the frequency of BDs aggregately and separately for the TTHM exposure groups, adjusting for maternal age and socioeconomic status. RESULTS: Total THMs ranged from 36 to 190 µg/L. A high proportion of the THMs were brominated (on average, 92%). Women living in high-TTHM areas showed an increased risk of any BD [odds ratio (OR) = 1.22; 95% confidence interval (CI), 1.01--1.48] and for the major category of any cardiovascular BD (OR = 1.62; 95% CI, 1.04--2.51), compared with women living in low-TTHM areas. CONCLUSIONS: Brominated forms constituted the significant fraction of THMs in all areas. Small but statistically significant increases in risks of BDs were associated with residence in areas with high THMs. [ABSTRACT FROM AUTHOR]

This article highlights the complex interactions between anthropogenic ecological change and mosquito-borne disease patterns. Ancient Rome provides a historical case study of the possible interplay between deforestation and an increasing malarial disease burden, and examples drawn from across the globe suggest that the experience of Rome is being repeated today. The evidence calls for careful management of agricultural clearing and for a multidisciplinary perspective in policy development on the issue, particularly in regions where there are already indications of escalating disease rates. [ABSTRACT FROM AUTHOR]

Objectives: To assess the risks for adult-onset acute leukemia associated with electrical employment in New Zealand.Methods: The occupational and environmental exposures histories of 110 incident leukemia cases and 199 general population controls were compared. The cases were recruited through referrals to treatment centers in New Zealand between 1989 and 1991. For subjects classified as having worked in one or more of the "electrical occupations," the degree of exposures to extremely low frequency electromagnetic fields (ELF-EMFs) was assessed in detail using a job-exposure matrix.Results: An odds ratio of 1.9 (95% Cl 1.0-3.8) was found for subjects who had ever worked in an electrical occupation. Significantly increased risks for leukemia are seen amongst welders/flame cutters (OR = 2.8 (95% CI 1.2-6.8)) and telephone line workers (OR = 5.81 (95% CI 1.2-27.8)). The excess leukemia risk appeared to be confined to acute non-lymphocytic leukemia (OR=2.31 (95% CI 1.2-4.6)), in comparison to acute lymphoblastic leukemia (OR = 0.9 (95% CI 0.3-2.9)) but for the latter category the numbers were very small. A dose-response effect was also found, with acute leukemia risk rising with increasing occupational magnetic field exposure, based on both current and historical occupational field exposure estimates.Conclusions: The findings of the current study indicate a significantly elevated risk of acute leukemia for electrical workers overall, and for the specific occupational categories of welders/flame cutters and telephone line workers. A dose-response effect was also found, indicating that acute leukemia risk was related to historical and current magnetic field exposures in an occupational context. [ABSTRACT FROM AUTHOR]

Previous research on general practitioners' (GPs') involvement in end‐of‐life care has largely focused on a specific aspect of care or has provided broad overviews that failed to capture individual variations in patient management. This qualitative study aimed to explore Australian GPs' feedback and reflections on the individual‐level care provided for patients in their last year of life. The findings of the study were drawn from a nation‐wide survey of GPs' experiences in end‐of‐life care. We analysed responses from 63 GPs for 267 of the 272 reported deaths. Factors influencing delivery of optimal end‐of‐life care reported by GPs were categorised into four groups: patient‐related factors, carer‐related factors, interactions between GPs and patients/carer‐related factors and broader health system issues. Each group included both barriers and facilitators. Our study highlighted importance of the emotional dimensions of therapeutic relationships with patients and their family, availability and capacity of family support and smooth communication and continuity of care between GPs and hospitals in delivery of optimal end‐of‐life care. Lack of these facilitators, misconceptions of palliative care and conflicts on implementing care plans among patients and their family tended to impede delivery of such care. On the basis of our findings in the present study and previous literature, we conclude that improved end‐of‐life care in general practice requires comprehensive approaches to supporting both the GP and family to provide care in patients' preferred place, such as enhanced palliative care training and improved availability of external support for GPs, higher levels of hospital‐based services reaching into community settings and broader community‐based resources for families beyond simply the healthcare system. [ABSTRACT FROM AUTHOR]

Though significant research highlights higher rates of mental ill-health and substance use among trans, non-binary and gender diverse (henceforth ‘trans’) young people, little research has considered patterns, contextual characteristics, and correlates of co-occurring experiences of mental ill-health and substance use among trans young people. Using data from the Trans Pathways study, we used prevalence ratios and age- and gender-adjusted logistic regression models to examine prevalence and differences of co-occurring substance use (past six-month cigarette use, alcohol use, and other drug use) and contextual characteristics of substance use (past six-month solitary alcohol and/or drug use, substance use for coping) by mental ill-health (depression disorder, anxiety disorder, past 12-month self-harm thoughts and behaviours, suicidal thoughts, planning, and attempt/s). Age- and gender-adjusted models assessed associations between co-occurring depressive and anxiety disorders and recent cigarette, alcohol, and other drug use (six co-occurring items total) and 18 interpersonal stressors. Significantly increased odds of smoking or recent use of cannabis or sedatives was observed among trans young people reporting depressive disorder, anxiety disorder (aORs ranging 1.8–3.1). Trans young people who reported recent smoking or use of cannabis, inhalants, or sedatives, had 40% to 80% reduced odds of past 12-month self-harm thoughts, self-harm behaviours, suicidal thoughts, and suicide attempt/s (aORs ranging 0.2–0.6). On the other hand, solitary alcohol and/or other drug use and substance use for coping was significantly associated with increased odds of all mental ill-health outcomes. Issues with school, secure housing, and intimate partner abuse were the most robust correlates of co-occurring mental ill-health and substance use. Trans young people using substances, especially cigarettes, cannabis, and sedatives, often so do with co-occurring experiences of depression and anxiety though limited substance use in more ‘social’ contexts may confer benefits for preventing self-harm and suicide thoughts and behaviours. Continued research in partnership with trans young people is warranted to conceptualise more nuanced and precise conceptual parameters of trans-affirming substance use harm reduction approaches. [ABSTRACT FROM AUTHOR]

LGBTQA+ young people experience suicidal thoughts and behaviors at a much greater rate than their heterosexual and cisgender peers. This study explored firsthand accounts of the coping strategies employed by LGBTQA+ young people when experiencing suicidal thoughts and behaviors. LGBTQA+ young people (N = 27; ages 14–25) in Australia with a history of suicidal thoughts and/or attempts participated in semi-structured interviews. Using reflexive thematic analysis, four major themes were developed: (1) It’s about the journey, not the destination, (2) Connecting with others, (3) When I knew better, I coped better, and (4) Doing the best I can with what I have. LGBTQA+ young people reported utilizing a range of coping strategies, however these were limited by a lack of knowledge around mental health, gender and sexuality diversity, and available resources. Experiences of discrimination within support settings and limited access to clinicians with knowledge of sexuality and gender diversity were cited as significant barriers. Interventions to increase mental health literacy in LGBTQA+ young people and improvements to clinician knowledge of sexuality and gender diversity are needed to enhance LGBTQA+ young people’s access to effective coping strategies when experiencing suicidal thoughts and behaviors. [ABSTRACT FROM AUTHOR]

There is a growing emphasis on the importance of availability of specialist palliative care for people living with dementia. However, for people imminently dying with dementia, we still have little knowledge about their palliative care needs and utilization of different specialist services. To (i) assess palliative care needs and other clinical and social characteristics of people imminently dying with dementia on their last admission in the context of community and inpatient palliative care services before death; (ii) compare care needs between patients requiring community-based and inpatient services; (iii) determine how and whether such care needs affect utilization of different palliative care services. Observational study using data from the Australian Palliative Care Outcomes Collaboration. Specialist palliative care services across Australia registered in the Palliative Care Outcomes Collaboration. A total of 3361 people who required specialist palliative care principally for dementia (including Alzheimer's disease and other dementias), and whose death occurred between 1 January 2013 and 31 December 2018. Five validated clinical instruments were used to collect point-of-care outcomes on each individual's function (Resource Utilisation Groups - Activities of Daily Living & Australia-modified Karnofsky Performance Status), symptom distress (Symptoms Assessment Scale & Palliative Care Problem Severity Score) and other clinical characteristics (Palliative Care Phases). We fitted multivariate logistic regression models to examine the association between these clinical outcomes and utilization of different specialist palliative care services. The majority of people imminently dying with dementia had absent or mild levels of symptom distress but experienced high levels of functional decline and needed substantial assistance with basic tasks of daily living in their last days of life. Large disparities in symptoms distress and functional decline between inpatient and community groups were not observed although differences in assessment scores were often statistically significant. Poor functional outcomes (odds ratio = 1.77, 95% confidence interval: 1.24–2.52) and "non-stable" palliative care phases (odds ratio =24.51, 95% confidence interval: 12.03–49.96) were positively associated with use of inpatient versus community palliative care, whereas there was no clear association between the majority of symptoms and use of different care services. The majority of people imminently dying with dementia could potentially benefit from greater access to supportive services in the community. Development of a dementia-specific palliative care pathway is needed to promote needs-based palliative care delivery models. the majority of people imminently dying with dementia could potentially benefit from greater access to supportive services in community. [ABSTRACT FROM AUTHOR]