The world is on the brink of tipping points for climate disaster and transformative action. Decisions taken now will shape the health of millions. So, will the Australian Government use its COP31 Presidency of Negotiations to prioritise the health of current and future generations and champion the end of fossil fuels? Despite recent positive shifts in some areas of climate policy, Australia's status as the world's third largest exporter of fossil fuels means strong pressure must be applied from the health professions to maximise political, social and economic progress towards a health-focussed transition to a sustainable society.

Climate change increasingly threatens global health as more frequent extreme heat events, combined with varying humidity levels, exacerbate both direct and indirect health risks, strain energy resources, and lead to economic loss. Vulnerable populations, including the elderly, young children, and those with preexisting health conditions, face greater risks due to lower physiological adaptive capacity. Those from socioeconomically disadvantaged communities are also vulnerable because of increased exposure and reduced capacity. While research has expanded our understanding of the physiological effects of extreme heat and humidity, challenges persist, including inconsistent data, lack of unified heat wave definitions, and limited knowledge of their impact on mortality and morbidity especially in specific populations. Addressing these challenges requires enhanced data and a comprehensive evaluation of humidity's modifying effects. Global collaboration to strengthen heat health action plans is essential, with future efforts focusing on enhancing the accessibility and effectiveness of interventions, especially in underresourced regions.

The modern field of 'planetary health' was instigated in 2015 by the Rockefeller Foundation-Lancet Commission, which defined it as 'the health of human civilisation and the state of the natural systems on which it depends'. However, this view of human health in relation to natural systems is not really new at all. Rather, it is (re)emerging as the environmental impacts of human activities and their effects on the health of all life on Earth, now and in the future, become increasingly clear. A planetary health approach requires us to rethink dominant perspectives about how we feed, move, house, power and care for the world, as well as the implications for wellbeing and equity across generations and locations. This shift in understanding of our place as humans in relation to the planet is fundamental to addressing the polycrises of the 21st century. Planetary health approaches are increasingly embraced but not yet fully realised or embedded. More organisations and collaborations, in the health sector and beyond, are incorporating these ideas into their methods, plans and training, including concepts that are part of, but not synonymous with planetary health, such as one health, global health, environmental health, climate health and sustainable healthcare. Yet, we are still far from the collective cultural transformation needed to achieve the promise of planetary health as a movement that puts the health of people and the planet at the centre of all policy and action. Education and training in the Western tradition encourage 'human-centred' or 'colonial' thinking. There is much to (re)learn from First Nations peoples, and other non-Western worldviews, about the interdependence of all species and what that means for sustainable health and wellbeing. We offer proposals for how public health policymakers, researchers and practitioners, might support the transformation needed and address the conceptual, knowledge and governance challenges identified by the Rockefeller Foundation-Lancet Commission.

The 28th Conference of the Parties (COP28) to the United Nations Framework Convention on Climate Change marked a step-change forward in integrating health into the global climate change agenda. For the first time, there was a dedicated ‘health’ day, US$1 billion (A$1.5 billion) in climate-health financing was announced, and a Declaration on Climate and Health was signed by 148 countries. Australia also launched its National Health and Climate Strategy. A ‘global stocktake’ assessed progress against the Paris Agreement, emphasising the need to ”transition away” from fossil fuels in the final COP28 decision. The Loss and Damage Fund to help vulnerable countries cope with climate change was also operationalised. Less promising are a number of loopholes in the COP28 outcomes regarding the continued use of fossil fuels. Loss and Damage Fund pledges represented only 0.2% of the estimated financial assistance needed to support vulnerable countries. Australia remains one of the largest fossil fuel exporters and has yet to elaborate on the implementation and financing for its health and climate strategy. To protect global health, urgent action is needed to phase out fossil fuels and transition to renewable energy, ensuring no communities are left behind. Investment is needed to increase the resilience of communities and health services to address innumerable challenges, including those associated with climate change. COP28 saw an increased presence of public health practitioners, who can play a critical role in understanding the implications of climate change for the communities they serve and embedding responses in their practice. They are well placed to strengthen the evidence base for interventions, monitor progress, and advocate for health-promoting climate policy. COPs form an important part of how we collectively address climate change. The health sector finally has a place at the COP table. The sector now needs to become an enabler of action across sectors, as well as managing the health consequences of climate change on communities and health services. Australia hopes to host COP31 in 2026 with Pacific states, potentially providing a catalyst for strengthened resolve.

The Australian Global Health Alliance, on behalf of the Australian global health community, stands united, deeply concerned about the health impacts of climate change across the world. The Alliance is the member-based peak body for Australian global health organisations, with a mandate to strengthen the global health ecosystem through national and global connections, supporting research and innovation and creating platforms to engage the global health community with government, the private sector, and the arts (https://ausglobalhealth.org/about-us/). Since its establishment in 2016, the Alliance is currently the only OECD country global health alliance with a commitment to First Nations global health equity as part of its foundational mandate. The current strategic focus of the Alliance is on healthy equity overall, planetary health, gender equality, and First Nations global health. The Alliance recognises the convergence of human-induced climate change with other human-induced global challenges — economic inequities, disease pandemics, biodiversity loss, environmental catastrophes, and geopolitical conflict — all of which have an impact on human health. This is a poly-crisis with the complex and interconnected risks of climate change posing significant challenges to society. We acknowledge that a key driver underlying these crises is an anthropocentric worldview that places human needs above those of nature. Yet, the health of people and the health of the planet are deeply enmeshed — humanity is a part of nature and not apart from nature. We are already witnessing the impacts of climate change on people's physical and mental health resulting from extreme weather events, and damage to the natural and human systems on which our health relies. The World Health Organization estimates that between 2030 and 2050, climate change is expected to cause about 250 000 deaths per year from malnutrition, malaria, diarrhoea, and heat stress.1 Climate change worsens food and water insecurity, changes infectious disease patterns, exacerbates chronic disease, and causes loss of homes and livelihoods, all leading to more illness and death. It also adds strain to health care systems continuing to deal with the effects of the COVID-19 pandemic.2 Low and middle income countries, especially in the Asia–Pacific region, bear the brunt of climate change impacts, despite contributing fewer emissions than high income nations. Australia's Pacific Island neighbours in particular face substantial ramifications relative to the emission-heavy Global North.3 Climate change amplifies existing health inequities, including gender-based inequities, and threatens to undo progress made in strengthening health systems in our region and globally.1 Tackling climate change not only safeguards our planet's future but also brings about many co-benefits for health and wellbeing. For example, a transition away from fossil fuel combustion to renewable energy generation could save over one million lives per year from reduction in outdoor fine particulate (particles < 2.5 μm aerodynamic diameter, PM2.5) pollution alone.4 Healthy sustainable diets5 and greater use of walking, cycling and public transport6 could reap physical and mental health benefits. Our response to climate change also presents an opportunity to reconnect our understanding of the indivisibility of human health with the health of the planet, as First Nations peoples have known for millennia, and to strengthen our resolve to protect and restore the foundations of health — our natural environments. Even if the current Paris Agreement nationally determined contributions and long term net zero targets are fully achieved, global mean temperatures are expected to increase by 1.7–2.1°C.7 The Intergovernmental Panel on Climate Change has shown that accelerated action is needed to cut global emissions by almost half by 2030 if warming is to be limited to 1.5°C above pre-industrial levels, as well as to adapt to the climate change that is already locked in.3 This is a critical decade for action. The multifaceted challenges we face demand a collective effort on an unprecedented scale. It is imperative that we act swiftly, drawing from the wealth of scientific evidence available, to address these challenges. We possess the expertise to assess the health impacts of climate change, develop strategies for resilience, and advocate for policies that prioritise both planetary and human wellbeing. For example, there is good evidence that cheaper and lower carbon cooling strategies, such as the use of electric fans rather than air conditioning, have the potential to reduce negative health outcomes in many high temperature environments.8 This exemplifies how research can pave the way for innovative interventions that serve both our immediate health needs and the long term sustainability of our planet. To drive transformative change, our policies must be co-designed and foster community-led responses, build capability and capacity, ensure policy coherence, leverage financial instruments effectively, and incentivise progress. These efforts must be woven into the fabric of our institutions, particularly training of the current and future health workforce, promoting skills for sustainability and resilience, as well as interdisciplinary connections, to instil a climate change and health lens across all sectors. By reorienting our systems now, for the sake of our planet and our health, we can set the stage for a legacy that benefits both the current and succeeding generations. With the United Nations Climate Change Conference of the Parties (COP28) being held in late November and early December 2023 — the first ever COP with a dedicated health day and climate and health ministerial meeting — we welcome the increased focus of the international community on the health implications of climate change. We look forward to progress on priority policy and investment actions for health systems, and funding commitments to fill the finance gap for international development work in climate and health. We note that recent assessments have found that only 2% of climate adaptation funding and 0.5% of multilateral climate funding has been explicitly allocated for human health.9 Using the holistic framework of the Sustainable Development Goals (https://sdgs.un.org/goals), we recognise that we must transform one of our greatest global health threats into our greatest global opportunity. Presently, Australia is in a unique position to leverage its influence and align efforts in global health with the opportunities that responding to the climate change crisis provides. Australia must align its actions with its stated commitments, ensuring that its approach, across all sectors and international endeavours, incorporates a robust climate change and health perspective. We acknowledge the members of the Australian Global Health Alliance's Climate Change and Global Health workshop held on 19 September 2023 and the members of the Alliance who contributed to the thinking behind this article, as well as the Australian Global Health Alliance as a collective that has committed to climate change and global health as a strategic objective. No relevant disclosures. Not commissioned; not externally peer reviewed.

IntroductionPathogens can enter the drinking water supply and cause gastroenteritis outbreaks. Such events can affect many people in a short time, making them a high risk for public health. In Australia, the Victoria State Government Department of Health is deploying a syndromic surveillance system for drinking water contamination events. We assessed the utility of segmented regression models for detecting such events and determined the number of excess presentations needed for such methods to signal a detection. MethodsThe study involved an interrupted time series study of a past lapse in water treatment. The baseline period comprised the four weeks before the minimum incubation period of suspected pathogens, set at two days post-event. The surveillance period comprised the week after. We used segmented linear regression to compare the count of gastroenteritis presentations to public hospital emergency departments (EDs) between the surveillance and baseline periods. We then simulated events result-ing in varying excess presentations. These were superimposed onto the ED data over fifty different dates across 2020. Using the same regression, we calculated the detection probability at p < 0.05 for each outbreak size.ResultsIn the retrospective analysis, there was strong evidence for an increase in presentations shortly after the event. In the simulations, with no excess presentations (i.e., with the ED data as is) the models signalled 8% probability of detection. The models returned 50% probability of detection with 28 excess presentations and 100% probability of detection with 78 excess presentations.ConclusionsThe transient increase in presentations after the event may be attributed to microbiological hazards or increased health-seeking behaviour following the issuing of boil water advisories. The simulations demonstrated the ability for segmented regressions to signal a detection, even without a large excess in presentations. The approach also demonstrated high specificity and should be considered for informing Victoria's syndromic surveillance system.

Climate change presents a major public health concern in Australia, marked by unprecedented wildfires, heatwaves, floods, droughts, and the spread of climate-sensitive infectious diseases. Despite these challenges, Australia's response to the climate crisis has been inadequate and subject to change by politics, public sentiment, and global developments. This study illustrates the spatiotemporal patterns of selected climate-related environmental extremes (heatwaves, wildfires, floods, and droughts) across Australia during the past two decades, and summarizes climate adaptation measures and actions that have been taken by the national, state/territory, and local governments. Our findings reveal significant impacts of climate-related environmental extremes on the health and well-being of Australians. While governments have implemented various adaptation strategies, these plans must be further developed to yield concrete actions. Moreover, Indigenous Australians should not be left out in these adaptation efforts. A collaborative, comprehensive approach involving all levels of government is urgently needed to prevent, mitigate, and adapt to the health impacts of climate change.

Objectives Our objective was to assess the health care system impacts associated with the December 2013 east coast flooding in Boston, Lincolnshire, in order to gain an insight into the capacity of the health care sector to respond to high-impact weather. Methods Semistructured interviews were held with regional strategic decision makers and local service managers within 1 km of the recorded flood outline to ascertain their experiences, views and reflections concerning the event and its associated health impacts and disruption to health care services. A snowballing sampling technique was used to ensure the study had participants across a broad range of expertise. Interviews were recorded and transcribed verbatim, and data analysis was preformed using NVivo (v10) to apply a thematic coding and develop a framework of ideas. Results The results of this case study provide a vital insight into the health care disruption caused by flooding. All sectors of the health care system suffered disruption, which placed a strain on the whole system and reduced the capacity of the sector to respond to the health consequences of flooding and delivering routine health care. The formal recovery phase in Lincolnshire was stood-down on 4th February 2014. The results of this work indicate limitations in preparedness of the health care system for the reasonable worse-case scenario for an east coast surge event. Conclusions The health care sector appears to have limited capacity to respond to weather-related impacts and is therefore unprepared for the risks associated with a future changing climate. Further work is required to ensure that the health care system continues to review and learn from such events to increase climate resilience.

Spending time in natural environments can benefit health and well-being, but exposure-response relationships are under-researched. We examined associations between recreational nature contact in the last seven days and self-reported health and well-being. Participants (n = 19,806) were drawn from the Monitor of Engagement with the Natural Environment Survey (2014/15–2015/16); weighted to be nationally representative. Weekly contact was categorised using 60 min blocks. Analyses controlled for residential greenspace and other neighbourhood and individual factors. Compared to no nature contact last week, the likelihood of reporting good health or high well-being became significantly greater with contact ≥120 mins (e.g. 120–179 mins: ORs [95%CIs]: Health = 1.59 [1.31–1.92]; Well-being = 1.23 [1.08–1.40]). Positive associations peaked between 200–300 mins per week with no further gain. The pattern was consistent across key groups including older adults and those with long-term health issues. It did not matter how 120 mins of contact a week was achieved (e.g. one long vs . several shorter visits/week). Prospective longitudinal and intervention studies are a critical next step in developing possible weekly nature exposure guidelines comparable to those for physical activity.

Floods are a significant public health problem linked with increased psychological morbidity. We aimed to investigate the effect of insurance-related factors on the association between flooding and probable mental health outcomes. We performed a secondary analysis of cross-sectional survey data from the English National Study of Flooding and Health (NSFH) collected two years after an initial flooding event in 2013-14. Our analysis focused on 851 respondents who experienced flooding or disruption. Multivariable logistic regression models were run for each exposure group. Among those whose homes had been flooded, not having household insurance was associated with increased odds of all outcomes compared to those with household insurance, significantly so for post-traumatic stress disorder (PTSD) (aOR 4.31, 95% CI 1.31–14.20). Those who reported severe stress due to insurance issues had increased odds of probable depression (aOR 11.08, 95% CI 1.11–110.30), anxiety (aOR 4.48, 95% CI 1.02–19.70) and PTSD (aOR 7.95, 95% CI 2.10–30.1) compared to those reporting no/mild stress. The study suggests there is increased psychological morbidity amongst the uninsured and those who report feeling severe stress as a result of insurance issues associated with flooding. Services should be prepared to support communities through insurance processes, to reduce probable mental health morbidity following a flood event.

Increasingly, the potential short and long-term impacts of climate change on human health and wellbeing are being demonstrated. However, other environmental change factors, particularly relating to the natural environment, need to be taken into account to understand the totality of these interactions and impacts. This paper provides an overview of ongoing research in the Health Protection Research Unit (HPRU) on Environmental Change and Health, particularly around the positive and negative effects of the natural environment on human health and well-being and primarily within a UK context. In addition to exploring the potential increasing risks to human health from water-borne and vector-borne diseases and from exposure to aeroallergens such as pollen, this paper also demonstrates the potential opportunities and co-benefits to human physical and mental health from interacting with the natural environment. The involvement of a Health and Environment Public Engagement (HEPE) group as a public forum of “critical friends” has proven useful for prioritising and exploring some of this research; such public involvement is essential to minimise public health risks and maximise the benefits which are identified from this research into environmental change and human health. Research gaps are identified and recommendations made for future research into the risks, benefits and potential opportunities of climate and other environmental change on human and planetary health.