Act Health

This comprehensive review unfolds a detailed narrative of Artificial Intelligence (AI) making its foray into radiology, a move that is catalysing transformational shifts in the healthcare landscape. It traces the evolution of radiology, from the initial discovery of X-rays to the application of machine learning and deep learning in modern medical image analysis. The primary focus of this review is to shed light on AI applications in radiology, elucidating their seminal roles in image segmentation, computer-aided diagnosis, predictive analytics, and workflow optimisation. A spotlight is cast on the profound impact of AI on diagnostic processes, personalised medicine, and clinical workflows, with empirical evidence derived from a series of case studies across multiple medical disciplines. However, the integration of AI in radiology is not devoid of challenges. The review ventures into the labyrinth of obstacles that are inherent to AI-driven radiology-data quality, the 'black box' enigma, infrastructural and technical complexities, as well as ethical implications. Peering into the future, the review contends that the road ahead for AI in radiology is paved with promising opportunities. It advocates for continuous research, embracing avant-garde imaging technologies, and fostering robust collaborations between radiologists and AI developers. The conclusion underlines the role of AI as a catalyst for change in radiology, a stance that is firmly rooted in sustained innovation, dynamic partnerships, and a steadfast commitment to ethical responsibility.

OBJECTIVE: To examine whether past high sun exposure is associated with a reduced risk of multiple sclerosis. DESIGN: Population based case-control study. SETTING: Tasmania, latitudes 41-3 degrees S. PARTICIPANTS: 136 cases with multiple sclerosis and 272 controls randomly drawn from the community and matched on sex and year of birth. MAIN OUTCOME MEASURE: Multiple sclerosis defined by both clinical and magnetic resonance imaging criteria. RESULTS: Higher sun exposure when aged 6-15 years (average 2-3 hours or more a day in summer during weekends and holidays) was associated with a decreased risk of multiple sclerosis (adjusted odds ratio 0.31, 95% confidence interval 0.16 to 0.59). Higher exposure in winter seemed more important than higher exposure in summer. Greater actinic damage was also independently associated with a decreased risk of multiple sclerosis (0.32, 0.11 to 0.88 for grades 4-6 disease). A dose-response relation was observed between multiple sclerosis and decreasing sun exposure when aged 6-15 years and with actinic damage. CONCLUSION: Higher sun exposure during childhood and early adolescence is associated with a reduced risk of multiple sclerosis. Insufficient ultraviolet radiation may therefore influence the development of multiple sclerosis.

'Health literacy' refers to accessing, understanding and using information to make health decisions. However, despite its introduction into the World Health Organization's Health Promotion Glossary, the term remains a confusing concept. We consider various definitions and measurements of health literacy in the international and Australian literature, and discuss the distinction between the broader concept of 'health literacy' (applicable to everyday life) and 'medical literacy' (related to individuals as patients within health care settings). We highlight the importance of health literacy in relation to the health promotion and preventive health agenda. Because health literacy involves knowledge, motivation and activation, it is a complex thing to measure and to influence. The development of health literacy policies will be facilitated by better evidence on the extent, patterns and impact of low health literacy, and what might be involved in improving it. However, the current lack of consensus of definitions and measurement of health literacy will first need to be overcome.

Nephrogenesis is ongoing at the time of birth for the majority of preterm infants, but whether postnatal renal development follows a similar trajectory to normal in utero growth is unknown. Here, we examined tissue collected at autopsy from 28 kidneys from preterm neonates, whose postnatal survival ranged from 2 to 68 days, including 6 that had restricted intrauterine growth. In addition, we examined kidneys from 32 still-born gestational controls. We assessed the width of the nephrogenic zone, number of glomerular generations, cross-sectional area of the renal corpuscle, and glomerular maturity and morphology. Renal maturation accelerated after preterm birth, with an increased number of glomerular generations and a decreased width of the nephrogenic zone in the kidneys of preterm neonates. Of particular concern, compared with gestational controls, preterm kidneys had a greater percentage of morphologically abnormal glomeruli and a significantly larger cross-sectional area of the renal corpuscle, suggestive of renal hyperfiltration. These observations suggest that the preterm kidney may have fewer functional nephrons, thereby increasing vulnerability to impaired renal function in both the early postnatal period and later in life.

Paratuberculosis, a chronic disease affecting ruminant livestock, is caused by Mycobacterium avium subsp. paratuberculosis (MAP). It has direct and indirect economic costs, impacts animal welfare and arouses public health concerns. In a survey of 48 countries we found paratuberculosis to be very common in livestock. In about half the countries more than 20% of herds and flocks were infected with MAP. Most countries had large ruminant populations (millions), several types of farmed ruminants, multiple husbandry systems and tens of thousands of individual farms, creating challenges for disease control. In addition, numerous species of free-living wildlife were infected. Paratuberculosis was notifiable in most countries, but formal control programs were present in only 22 countries. Generally, these were the more highly developed countries with advanced veterinary services. Of the countries without a formal control program for paratuberculosis, 76% were in South and Central America, Asia and Africa while 20% were in Europe. Control programs were justified most commonly on animal health grounds, but protecting market access and public health were other factors. Prevalence reduction was the major objective in most countries, but Norway and Sweden aimed to eradicate the disease, so surveillance and response were their major objectives. Government funding was involved in about two thirds of countries, but operations tended to be funded by farmers and their organizations and not by government alone. The majority of countries (60%) had voluntary control programs. Generally, programs were supported by incentives for joining, financial compensation and/or penalties for non-participation. Performance indicators, structure, leadership, practices and tools used in control programs are also presented. Securing funding for long-term control activities was a widespread problem. Control programs were reported to be successful in 16 (73%) of the 22 countries. Recommendations are made for future control programs, including a primary goal of establishing an international code for paratuberculosis, leading to universal acknowledgment of the principles and methods of control in relation to endemic and transboundary disease. An holistic approach across all ruminant livestock industries and long-term commitment is required for control of paratuberculosis.

OBJECTIVE: To estimate the prevalence of mental disorders in children and adolescents in Australia, and the severity and impact of those mental disorders. METHOD: Seven mental disorders were assessed using the parent- or carer-completed version of the Diagnostic Interview Schedule for Children Version IV, and major depressive disorder was also assessed using the youth self-report version of the Diagnostic Interview Schedule for Children Version IV. Severity and impact were assessed using an extended version of the Diagnostic Interview Schedule for Children Version IV impact on functioning questions, and days absent from school due to symptoms of mental disorders. Data were collected in a national face-to-face survey of 6310 parents or carers of children and adolescents aged 4-17 years, with 2969 young people aged 11-17 years also completing a self-report questionnaire. RESULTS: Twelve-month prevalence of mental disorders was 13.9%, with 2.1% of children and adolescents having severe disorders, 3.5% having moderate disorders and 8.3% having mild disorders. The most common class of disorders was attention-deficit/hyperactivity disorder followed by anxiety disorders. Mental disorders were more common in step-, blended- or one-parent families, in families living in rented accommodation and families where one or both carers were not in employment. Mental disorders were associated with a substantial number of days absent from school particularly in adolescents. CONCLUSION: Mental disorders are common in children and adolescents, often have significant impact and are associated with substantial absences from school. Child and adolescent mental disorders remain an important public health problem in Australia. Accurate information about prevalence and severity of child and adolescent mental disorders is an essential prerequisite for effective mental health policy and service planning.

OBJECTIVES: To assess the impact of a specifically designed model of orthopedic-geriatric cocare on hip fracture (HF) outcomes. SETTING: Tertiary teaching hospital (level I trauma center). DESIGN: Prospective observational study with a retrospective (historical) control. Data on 951 consecutive patients 60 years of age or older admitted to the authors' institution with a nonpathologic HF over a 7-year period (1995 to 2002) were analyzed. Between 1995 and 1997, medical problems were managed by a geriatric medicine (GM) consultation-only service (retrospective audit). In 1998, a GM registrar began overseeing daily medical care with weekly geriatrician consultant review (prospective study). Outcomes for 2 time periods were compared: a 3-year period before (no GM; 504 patients) and a 4-year period after (GM; 447 patients) the introduction of GM cocare. MAIN OUTCOME MEASUREMENTS: Postoperative medical complications, mortality, length of stay, discharge destination, use of thromboprophylaxis, and antiosteoporotic treatment. RESULTS: While comparing 2 periods (GM and no GM), significant reductions in postoperative medical complications and comorbid conditions (in total 49.5% vs. 71.0%, P<0.001) and mortality (4.7% vs. 7.7%, P<0.01) occurred and rehospitalization to medical wards within 6 months decreased (28% vs. 7.6%). However, no differences were observed in median length of hospital stay (10.8 vs. 11.0 days) or in discharge destination. Antiosteoporotic treatment (12% to 69%) and specific thromboprophylaxis (63% to 94%) increased in the GM period. CONCLUSIONS: Orthopedic-geriatric cocare for the older patients with HF was associated with significant reductions in morbidity and mortality, and increases in optimal postoperative care. Options for further improvement of orthopedic-GM cocare need to be investigated.

INTRODUCTION: The use of simulation in health professional education has increased rapidly over the past 2 decades. While simulation has predominantly been used to train health professionals and students for a variety of clinically related situations, there is an increasing trend to use simulation as an assessment tool, especially for the development of technical-based skills required during clinical practice. However, there is a lack of evidence about the effectiveness of using simulation for the assessment of competency. Therefore, the aim of this systematic review was to examine simulation as an assessment tool of technical skills across health professional education. METHODS: A systematic review of Cumulative Index to Nursing and Allied Health Literature (CINAHL), Education Resources Information Center (ERIC), Medical Literature Analysis and Retrieval System Online (Medline), and Web of Science databases was used to identify research studies published in English between 2000 and 2015 reporting on measures of validity, reliability, or feasibility of simulation as an assessment tool. The McMasters Critical Review for quantitative studies was used to determine methodological value on all full-text reviewed articles. Simulation techniques using human patient simulators, standardized patients, task trainers, and virtual reality were included. RESULTS: A total of 1,064 articles were identified using search criteria, and 67 full-text articles were screened for eligibility. Twenty-one articles were included in the final review. The findings indicated that simulation was more robust when used as an assessment in combination with other assessment tools and when more than one simulation scenario was used. Limitations of the research papers included small participant numbers, poor methodological quality, and predominance of studies from medicine, which preclude any definite conclusions. CONCLUSION: Simulation has now been embedded across a range of health professional education and it appears that simulation-based assessments can be used effectively. However, the effectiveness as a stand-alone assessment tool requires further research.

mum estimates of the true burden of disease. In recognising this issue, we respectfully acknowledge the history of dispossession and intergenerational trauma that affects the lives of many Aboriginal and Torres Strait Islander people. We recognise that the provision of culturally appropriate health care services and systems are vital to support self-identification and prioritisation of the collection of these data.

OBJECTIVE: To provide a rapid clinical update on the evidence for telehealth in mental healthcare in the context of the COVID-19 pandemic public health measures. CONCLUSIONS: Telehealth has been rapidly implemented in metropolitan and rural settings and the existing evidence base demonstrates that it represents an effective mode of service delivery.

Primary ciliary dyskinesia (PCD) is a recessively inherited disease that leads to chronic respiratory disorders owing to impaired mucociliary clearance. Conventional transmission electron microscopy (TEM) is a diagnostic standard to identify ultrastructural defects in respiratory cilia but is not useful in approximately 30% of PCD cases, which have normal ciliary ultrastructure. DNAH11 mutations are a common cause of PCD with normal ciliary ultrastructure and hyperkinetic ciliary beating, but its pathophysiology remains poorly understood. We therefore characterized DNAH11 in human respiratory cilia by immunofluorescence microscopy (IFM) in the context of PCD. We used whole-exome and targeted next-generation sequence analysis as well as Sanger sequencing to identify and confirm eight novel loss-of-function DNAH11 mutations. We designed and validated a monoclonal antibody specific to DNAH11 and performed high-resolution IFM of both control and PCD-affected human respiratory cells, as well as samples from green fluorescent protein (GFP)-left-right dynein mice, to determine the ciliary localization of DNAH11. IFM analysis demonstrated native DNAH11 localization in only the proximal region of wild-type human respiratory cilia and loss of DNAH11 in individuals with PCD with certain loss-of-function DNAH11 mutations. GFP-left-right dynein mice confirmed proximal DNAH11 localization in tracheal cilia. DNAH11 retained proximal localization in respiratory cilia of individuals with PCD with distinct ultrastructural defects, such as the absence of outer dynein arms (ODAs). TEM tomography detected a partial reduction of ODAs in DNAH11-deficient cilia. DNAH11 mutations result in a subtle ODA defect in only the proximal region of respiratory cilia, which is detectable by IFM and TEM tomography.

OBJECTIVES: Working Group 2 was convened to address topics relevant to prosthodontics and dental implants. Systematic reviews were developed according to focused questions addressing (a) the number of implants required to support fixed full-arch restorations, (b) the influence of intentionally tilted implants compared to axial positioned implants when supporting fixed dental prostheses (FDPs), (c) implant placement and loading protocols, (d) zirconia dental implants, (e) zirconia and metal ceramic implant supported single crowns and (f) zirconia and metal ceramic implant supported FDPs. MATERIALS AND METHODS: Group 2 considered and discussed information gathered in six systematic reviews. Group participants discussed statements developed by the authors and developed consensus. The group developed and found consensus for clinical recommendations based on both the statements and the experience of the group. The consensus statements and clinical recommendations were presented to the plenary (gathering of all conference attendees) and discussed. Final versions were developed after consensus was reached. RESULTS: A total of 27 consensus statements were developed from the systematic reviews. Additionally, the group developed 24 clinical recommendations based on the combined expertise of the participants and the developed consensus statements. CONCLUSIONS: The literature supports the use of various implant numbers to support full-arch fixed prostheses. The use of intentionally tilted dental implants is indicated when appropriate conditions exist. Implant placement and loading protocols should be considered together when planning and treating patients. One-piece zirconia dental implants can be recommended when appropriate clinical conditions exist although two-piece zirconia implants should be used with caution as a result of insufficient data. Clinical performance of zirconia and metal ceramic single implant supported crowns is similar and each demonstrates significant, though different, complications. Zirconia ceramic FDPs are less reliable than metal ceramic. Implant supported monolithic zirconia prostheses may be a future option with more supporting evidence.

Alcoholic drinks are capable of triggering a wide range of allergic and allergic-like responses, including rhinitis, itching, facial swelling, headache, cough and asthma. Limited epidemiological data suggests that many individuals are affected and that sensitivities occur to a variety of drinks, including wine, beer and spirits. In surveys of asthmatics, over 40% reported the triggering of allergic or allergic-like symptoms following alcoholic drink consumption and 30 - 35% reported worsening of their asthma. Sensitivity to ethanol itself can play a role in triggering adverse responses, particularly in Asians, which is due mainly to a reduced capacity to metabolize acetaldehyde. In Caucasians, specific non-alcohol components are the main cause of sensitivities to alcoholic drinks. Allergic sensitivities to specific components of beer, spirits and distilled liquors have been described. Wine is clearly the most commonly reported trigger for adverse responses. Sensitivities to wine appear to be due mainly to pharmacological intolerances to specific components, such as biogenic amines and the sulphite additives. Histamine in wine has been associated with the triggering of a wide spectrum of adverse symptoms, including sneezing, rhinitis, itching, flushing, headache and asthma. The sulphite additives in wine have been associated with triggering asthmatic responses. Clinical studies have confirmed sensitivities to the sulphites in wine in limited numbers of individuals, but the extent to which the sulphites contribute to wine sensitivity overall is not clear. The aetiology of wine-induced asthmatic responses may be complex and may involve several co-factors.

BACKGROUND: Vitamin D (vitD) and L-arginine have important antimycobacterial effects in humans. Adjunctive therapy with these agents has the potential to improve outcomes in active tuberculosis (TB). METHODS: In a 4-arm randomised, double-blind, placebo-controlled factorial trial in adults with smear-positive pulmonary tuberculosis (PTB) in Timika, Indonesia, we tested the effect of oral adjunctive vitD 50,000 IU 4-weekly or matching placebo, and L-arginine 6.0 g daily or matching placebo, for 8 weeks, on proportions of participants with negative 4-week sputum culture, and on an 8-week clinical score (weight, FEV1, cough, sputum, haemoptysis). All participants with available endpoints were included in analyses according to the study arm to which they were originally assigned. Adults with new smear-positive PTB were eligible. The trial was registered at ClinicalTrials.gov NCT00677339. RESULTS: 200 participants were enrolled, less than the intended sample size: 50 received L-arginine + active vitD, 49 received L-arginine + placebo vit D, 51 received placebo L-arginine + active vitD and 50 received placebo L-arginine + placebo vitD. According to the factorial model, 99 people received arginine, 101 placebo arginine, 101 vitamin D, 99 placebo vitamin D. Results for the primary endpoints were available in 155 (4-week culture) and 167 (clinical score) participants. Sputum culture conversion was achieved by week 4 in 48/76 (63%) participants in the active L-arginine versus 48/79 (61%) in placebo L-arginine arms (risk difference -3%, 95% CI -19 to 13%), and in 44/75 (59%) in the active vitD versus 52/80 (65%) in the placebo vitD arms (risk difference 7%, 95% CI -9 to 22%). The mean clinical outcome score also did not differ between study arms. There were no effects of the interventions on adverse event rates including hypercalcaemia, or other secondary outcomes. CONCLUSION: Neither vitD nor L-arginine supplementation, at the doses administered and with the power attained, affected TB outcomes. REGISTRY: ClinicalTrials.gov. Registry number: NCT00677339.

Abstract Background There are few reports of new functional impairment following critical illness from COVID-19. We aimed to describe the incidence of death or new disability, functional impairment and changes in health-related quality of life of patients after COVID-19 critical illness at 6 months. Methods In a nationally representative, multicenter, prospective cohort study of COVID-19 critical illness, we determined the prevalence of death or new disability at 6 months, the primary outcome. We measured mortality, new disability and return to work with changes in the World Health Organization Disability Assessment Schedule 2.0 12L (WHODAS) and health status with the EQ5D-5L TM . Results Of 274 eligible patients, 212 were enrolled from 30 hospitals. The median age was 61 (51–70) years, and 124 (58.5%) patients were male. At 6 months, 43/160 (26.9%) patients died and 42/108 (38.9%) responding survivors reported new disability. Compared to pre-illness, the WHODAS percentage score worsened (mean difference (MD), 10.40% [95% CI 7.06–13.77]; p &lt; 0.001). Thirteen (11.4%) survivors had not returned to work due to poor health. There was a decrease in the EQ-5D-5L TM utility score (MD, − 0.19 [− 0.28 to − 0.10]; p &lt; 0.001). At 6 months, 82 of 115 (71.3%) patients reported persistent symptoms. The independent predictors of death or new disability were higher severity of illness and increased frailty. Conclusions At six months after COVID-19 critical illness, death and new disability was substantial. Over a third of survivors had new disability, which was widespread across all areas of functioning. Clinical trial registration NCT04401254 May 26, 2020.

OBJECTIVES: This study aimed to identify some of the correlates of self-rated health for young to middle-aged Australian women. METHODS: Regression analyses were based on a 4-year longitudinal study using a random sample of Sydney women 20 to 59 years of age at baseline. Participants were interviewed in 1986/87 and 1990. RESULTS: Cross-sectional relationships between self-assessed health and other health measures varied significantly by age, although physical health was a common correlate. Sixty-three percent of participants reported a similar rating of health over the 4-year period between the surveys. Changes in self-assessed health were sensitive to chronic disease. Also, participants' self-ratings of health were related to their subsequent chronic disease status. CONCLUSIONS: Self-rated health reflects a complex process of internalized calculations that encompass both lived experience and knowledge of disease causes and consequences. Women seem to take into consideration a broad range of factors, including lifestyle, vitality, mental attitude, and age, and, if they have a health condition, the chronicity of their disease, duration since diagnosis, and treatment.

OBJECTIVE: To report outcomes from the first 2 years of the National Hand Hygiene Initiative (NHHI), a hand hygiene (HH) culture-change program implemented in all Australian hospitals to improve health care workers' HH compliance, increase use of alcohol-based hand rub and reduce the risk of health care-associated infections. DESIGN AND SETTING: The HH program was based on the World Health Organization 5 Moments for Hand Hygiene program, and included standardised educational materials and a regular audit system of HH compliance. The NHHI was implemented in January 2009. MAIN OUTCOME MEASURES: HH compliance and Staphylococcus aureus bacteraemia (SAB) incidence rates 2 years after NHHI implementation. RESULTS: In late 2010, the overall national HH compliance rate in 521 hospitals was 68.3% (168,641/246,931 moments), but HH compliance before patient contact was 10%-15% lower than after patient contact. Among sites new to the 5 Moments audit tool, HH compliance improved from 43.6% (6431/14,740) at baseline to 67.8% (106,851/157,708) (P < 0.001). HH compliance was highest among nursing staff (73.6%; 116,851/158,732) and worst among medical staff (52.3%; 17,897/34,224) after 2 years. National incidence rates of methicillin-resistant SAB were stable for the 18 months before the NHHI (July 2007-2008; P = 0.366), but declined after implementation (2009-2010; P = 0.008). Annual national rates of hospital-onset SAB per 10,000 patient-days were 1.004 and 0.995 in 2009 and 2010, respectively, of which about 75% were due to methicillin-susceptible S. aureus. CONCLUSIONS: The NHHI was associated with widespread sustained improvements in HH compliance among Australian health care workers. Although specific linking of SAB rate changes to the NHHI was not possible, further declines in national SAB rates are expected.

INTRODUCTION: Systems thinking has emerged in recent years as a promising approach to understanding and acting on the prevention and amelioration of non-communicable disease. However, the evidence on inequities in non-communicable diseases and their risks factors, particularly diet, has not been examined from a systems perspective. We report on an approach to developing a system oriented policy actor perspective on the multiple causes of inequities in healthy eating. METHODS: Collaborative conceptual modelling workshops were held in 2015 with an expert group of representatives from government, non-government health organisations and academia in Australia. The expert group built a systems model using a system dynamics theoretical perspective. The model developed from individual mind maps to pair blended maps, before being finalised as a causal loop diagram. RESULTS: The work of the expert stakeholders generated a comprehensive causal loop diagram of the determinants of inequity in healthy eating (the HE2 Diagram). This complex dynamic system has seven sub-systems: (1) food supply and environment; (2) transport; (3) housing and the built environment; (4) employment; (5) social protection; (6) health literacy; and (7) food preferences. DISCUSSION: The HE2 causal loop diagram illustrates the complexity of determinants of inequities in healthy eating. This approach, both the process of construction and the final visualisation, can provide the basis for planning the prevention and amelioration of inequities in healthy eating that engages with multiple levels of causes and existing policies and programs.

3D printing is a form of rapid prototyping technology, which has led to innovative new applications in biomedicine. It facilitates the production of highly accurate three dimensional objects from substrate materials. The inherent accuracy and other properties of 3D printing have allowed it to have exciting applications in anatomy education and surgery, with the specialty of neurosurgery having benefited particularly well. This article presents the findings of a literature review of the Pubmed and Web of Science databases investigating the applications of 3D printing in anatomy and surgical education, and neurosurgery. A number of applications within these fields were found, with many significantly improving the quality of anatomy and surgical education, and the practice of neurosurgery. They also offered advantages over existing approaches and practices. It is envisaged that the number of useful applications will rise in the coming years, particularly as the costs of this technology decrease and its uptake rises.

More nuanced health advice is needed to protect populations and individuals from exposure to bushfire smoke Bushfires have always been a feature of the natural environment in Australia, but the risk has increased over time as fire seasons start earlier, finish later, and extreme fire weather (ie, very hot, dry and windy conditions that make fires fast moving and very difficult to control) becomes more severe with climate change.1-3 The 2019–20 bushfires in Australia, particularly in New South Wales, Victoria, Queensland and the Australian Capital Territory, have caused at least 33 fatalities, extensive damage to property and destruction of flora and fauna, and have exposed millions of people to extreme levels of air pollution. Bushfire smoke, as well as smoke from prescribed burns, contains a complex mixture of particles and gases that are chemically transformed in the atmosphere and transported by the wind over long distances.4 In this context, a major public health concern is population exposure to atmospheric particulate matter (PM) with a diameter < 2.5 μm (PM2.5), which can penetrate deep into the respiratory system, inducing oxidative stress and inflammation,5 and even translocate into the bloodstream.6 Such exposure can adversely affect health outcomes. Mortality rates have been found to increase in Sydney on days with high bushfire smoke pollution.7 Hospital admissions, emergency department attendances, ambulance call-outs and general practitioner consultations, particularly for respiratory conditions, all increase during periods of severe PM2.5 levels from bushfires.8-11 The risks from air pollution are amplified when combined with high temperatures during heatwaves, with an increased effect on mortality.12 Certain population groups are at higher risk from exposure to smoke, either because they typically breathe in more air per bodyweight and their organs are still developing (young children), spend more time outdoors (outdoor workers, homeless people), or are more vulnerable to smoke due to old age or a pre-existing health condition (asthma, chronic obstructive pulmonary disease or other respiratory condition, cardiovascular illness, or diabetes). There is evidence that exposure to bushfire smoke during pregnancy is associated with reduced birthweight in babies and a higher risk of gestational diabetes in mothers.13, 14 People in lower socio-economic groups are potentially at higher risk, as they may have poorer housing, and lower health literacy and ability to take preventive measures. Current health protection advice related to bushfire smoke mainly focuses on short term measures aimed at reducing personal exposure to pollution. This includes advice to stay indoors with windows and doors closed, and reduce strenuous physical exercise outdoors, particularly if individuals experience health symptoms or have pre-existing respiratory or cardiovascular conditions, when PM2.5 concentrations are increased. The PM2.5 national standard of 25 μg/m3 measured as a 24-hour mean (National Environment Protection (Ambient Air Quality) Measure: https://www.legislation.gov.au/Details/F2016C00215) is consistent with the World Health Organization's air quality guidelines.15 However, PM2.5 concentrations presented as hourly averages are more useful for planning daily activities, as these better reflect current air quality, which can change rapidly during bushfire episodes. Currently, state and territory government departments use a range of different air quality metrics (such as a composite Air Quality Index based on multiple pollutants), averaging times and thresholds to stratify health messages into colour-coded bands (very good, good, fair, poor, very poor, hazardous). The discrepancies in the presentation of this air quality information and related health advice across jurisdictions is confusing for the public. General advice also includes having access to regular medication, such as asthma medication, checking on older neighbours, and seeking medical attention if needed. Such advice, however, has been tailored to brief air pollution episodes that last only a few hours or days. In situations like the 2019–20 bushfire smoke events in eastern Australia, where severe smoke pollution persists over longer periods (weeks to months) and affects large population centres, there is a need for more nuanced and detailed health advice based on location-specific air quality data and forecasts. Reducing prolonged or heavy physical exercise outdoors may become impractical over longer periods; for example, for school children and outdoor workers. Children and adults need to carry out a range of daily activities that involve spending time outdoors. Advice to reduce strenuous physical exercise outdoors becomes problematic over longer periods, owing to the recognised health benefits from active travel (ie, walking and cycling) and regular outdoor exercise, and potential lack of access to indoor sports facilities. We believe that more nuanced advice would encourage individuals to be guided by location-specific air quality forecasts and the pattern of hourly PM2.5 concentrations at nearby air quality monitoring locations, and to plan their daily activities in ways that minimise exposure to pollution. For example, PM2.5 levels were lower in most locations in Sydney in early morning hours during the December 2019 bushfire smoke episode (Box 1, A). Exercising outdoors and cycling or walking to school or work within this time window would help maintain good physical activity levels without substantially increasing exposure to smoke. Locations in the city's north were affected by much higher PM2.5 concentrations than some locations in the south at the highest peak of smoke on 10 December 2019 (Box 1, B). Real time information on the temporal and spatial variation of air pollution in all jurisdictions should be made available online and through other media to enable individuals to assess nearby air quality. Avoiding pollution from other sources (road traffic, cigarette smoking, etc) is also advisable, although widespread bushfire smoke is likely to dominate personal exposure to PM2.5 during severe smoke events. PM2.5 = atmospheric particulate matter with a diameter < 2.5 μm. A: Hourly average PM2.5 data between 1 and 22 December 2019, downloaded for 15 air quality monitoring stations in the Sydney region from the New South Wales Department of Planning, Industry and Environment database (https://www.dpie.nsw.gov.au/air-quality/search-for-and-download-air-quality-data). The straight line represents the Australian PM2.5 standard of 25 μg/m3 measured as a 24-hour mean (National Environment Protection (Ambient Air Quality) Measure). Note that full data validation has not been completed for these records and they have only passed an initial automated validation process. B: Hourly average PM2.5 levels (μg/m3) at monitoring stations at the peak of the bushfire smoke event on 10 December 2019 at 1 pm. Advice to stay indoors may be ineffective over longer periods. Older houses in Australia are often quite “leaky”, allowing bushfire smoke to penetrate indoors over time and creating unhealthy indoor air quality conditions. Well sealed and air conditioned indoor environments (typically, modern apartments and offices, libraries and shopping centres) can provide respite from smoke pollution, particularly if effective air filtration systems are in place. However, many urban residents exposed to bushfire smoke, such as older people and those with restricted mobility, may not have easy access to such places. Temporary relocation to a different area or city could reduce exposure to air pollution during localised but persistent smoke episodes. However, relocation has its own risks and is impractical (particularly for older people and for those with cognitive or mobility problems), especially when larger geographical areas are affected by smoke.16 Temporary relocation to a dwelling with better indoor air quality (eg, a modern air conditioned apartment) within the same neighbourhood may be a more practical and less stressful solution for those at higher risk (eg, people with severe asthma, pregnant women, and older people). The priority for those affected should be to create a clean air space within their home, by sealing doors and windows and using air conditioning and filtration if possible, where they can spend most of their time during prolonged periods of bushfire smoke.17 However, many people may not be able to afford air conditioning and filtration units. Homes should be ventilated during periods of cleaner outdoor air quality (eg, around midnight in Sydney in December 2019; Box 1, A), to cool down the homes and avoid build-up of indoor pollutants. Access to regular medication, including asthma preventers and relievers, statins or aspirin, is important for people with pre-existing lung and heart conditions, and should be arranged in consultation with their GPs. Maintaining a healthy diet, with plenty of fruit and vegetables, and keeping well hydrated is likely to help reduce short and long term health effects. There is suggestive evidence that antioxidant and fish oil supplementation and dietary intake may have a protective effect against air pollution exposure;18, 19 however, more research is needed to support this. Much of the media attention during periods of bushfire smoke relates to the use of facemasks. These are increasingly used by the general public in highly polluted Asian cities, particularly in China.20 Use of facemasks during brief air pollution episodes (outside occupational settings and extreme air pollution emergencies related to volcanic eruptions) is not routinely recommended by health authorities. This is because their effectiveness depends heavily on the facial fit, material and condition of the masks. Surgical masks may have reasonable filtration efficiency; however, their design generally confers poor facial fit and high inward leakage of PM2.5.20 Professional P2 or N95 facemasks, which can provide very efficient filtration of PM2.5 if well fitted, are only designed for adults and can make breathing more difficult and increase thermal discomfort.20 More research is needed on the longer term health benefits and potential drawbacks of different types of facemasks for adults and children. Such masks do not confer protection from exposure to toxic gases in bushfire smoke (eg, carbon monoxide, nitrogen oxides and volatile organic compounds) that may be present closer to the fire front. There are a number of practical, medical and ethical considerations that should ultimately inform a decision about whether or not to recommend and distribute facemasks to the general public, outdoor workers and sensitive groups during air pollution emergencies.21, 22 Clear information about the effectiveness, benefits and drawbacks of different types of masks should be provided by health authorities to enable individuals, health professionals and employers to make informed decisions. Nuanced and balanced public health communication that takes into account health risks, people's concerns and the effectiveness and practicality of protective measures is needed. Bushfire smoke alerts, real time air quality data and forecasts, and related health protection advice (Box 2) can help to reduce population exposure to hazardous air pollution, by enabling individuals, particularly those more sensitive, to plan their daily activities accordingly. Source: Australian National University Research School of Population Health (https://rsph.anu.edu.au/news-events/news/how-protect-yourself-and-others-bushfire-smoke). Environmental health literacy and a better understanding of the causes and effects of bushfires, and of the health consequences of air pollution more broadly, are important. There may be a misconception that smoke from burning wood or other organic fuels is “natural”, hence not harmful to health. There is no consistent scientific evidence supporting this belief. Toxicological studies have consistently demonstrated that particles derived from biomass burning can activate inflammatory, oxidative and genotoxic responses, similar to road traffic particles.23 A recent systematic review of epidemiological studies has shown higher asthma-related effects for PM2.5 from landscape fire smoke compared with other sources.11 Comparison of pollutant concentrations with regulatory standards (eg, 24-hour PM2.5 average of 25 μg/m3) highlights the scale of the problem and drives institutional action. However, local air quality can change very rapidly. At a personal level, real time hourly PM2.5 data and smoke forecasts are more helpful for planning daily activities to reduce exposure to air pollution. The AirRater smartphone app (https://airrater.org/) shares location-specific hourly PM2.5 measurements from all jurisdictions. However, many locations affected by bushfire smoke do not have air quality monitoring stations. This highlights the need for increased air quality monitoring capabilities at state and territory level, including fixed monitoring sites, portable equipment and low cost sensors that can be rapidly deployed in a bushfire emergency. It should be emphasised that there is no safe level of exposure to PM2.5 and any reduction in exposure reduces the risk of mortality and morbidity. Health professionals often compare outdoor air pollution with cigarette smoke, as both contain mixtures of toxic chemicals and have the same route of exposure (ie, inhalation) and common health outcomes (eg, lung cancer and other respiratory illnesses, heart disease, mortality risk). Although equivalence of bushfire smoke exposure with smoking a specific number of cigarettes is debatable,24 the broader comparison helps raise awareness of the long term health risks associated with outdoor air pollution, and reinforces preventive measures. The unprecedented bushfire smoke levels in eastern Australia have raised concerns about short and long term health consequences in the affected populations. They have also tested the existing health protection advice, which mainly focuses on shorter and more localised smoke episodes, and methods for communicating air quality information. Exposed populations increasingly seek advice on interventions (eg, facemasks, air cleaners, daily activities) that can help people self-manage health risks from bushfire smoke. It is important that health professionals and patients, as well as healthy individuals and those at higher risk (eg, pregnant women and older people), develop a good understanding of the available health protection measures and their effectiveness and potential trade-offs (Box 3).25, 26 Public access to local, user-friendly air quality information and reliable smoke forecasts is essential for managing personal exposure as well as clinical deterioration in sensitive individuals. We strongly recommend that all Australian jurisdictions present actual hourly PM2.5 data rather than an index. Real time, hourly averaged PM2.5 concentrations are the most appropriate metric to guide personal behaviour that minimises exposure to bushfire smoke. Health messages need to be evidence-informed and specific for at-risk groups and the general public. More government investment is needed in air quality monitoring, forecasting and research on public health messaging, and exposure reduction measures to protect Australians from bushfire smoke. Consistency of air quality information and related public health advice across jurisdictions is essential. It is time for an independent national expert committee on air pollution and health protection to be established to support environmental health decision making in Australia. This new expert committee should have a clear mandate and resources to develop evidence-based, accurate, practical and consistent advice on health protection against bushfire smoke, and air pollution more broadly, across jurisdictions. Managing the health impacts of fire smoke should be integral to landscape fire planning and bushfire emergency response. Close collaboration between health, education, environmental, fire management and emergency response agencies is essential for achieving the best overall outcomes for population health and wellbeing. Further research is needed into the medium and longer term impacts of bushfire smoke, as well as the effectiveness and health equity implications of related health protection advice. Working towards ambitious climate change mitigation targets is an essential long term strategy for managing the underlying causes of the increasing bushfire risk in Australia and overseas. This research was undertaken with support from the Australian National University College of Health and Medicine, and the assistance of resources from the Centre for Air pollution, energy and health Research (CAR). We used the CAR Data and Analysis Technology platform (https://cardat.github.io) to analyse data. Sotiris Vardoulakis has received funding support from the UK National Institute for Health Research, Medical Research Council, Natural Environment Research Council, Public Health England, EU Horizon 2020, and Dyson Ltd. Geoffrey Morgan and Ivan Hanigan receive funding support from the Australian National Health and Medical Research Council. Not commissioned; externally peer reviewed.