Health impacts of war: case studies of New Zealand veterans of the First World War.

AIM: Armed conflict remains a tragic feature of the modern world and so it is necessary to continue to study its health impacts. Even the study of historical conflicts is relevant given that certain health impacts are common to most wars e.g., post-traumatic stress disorder (PTSD). METHODS: This study built on a previous quantitative analysis of a randomly selected group of 200 New Zealand veterans from the First World War (WWI). From this sample we selected 10 cases that illustrated particular themes around morbidity impacts. RESULTS: The theme of severity of impacts was illustrated with a case who was severely wounded and died from suicide when back in New Zealand, and another case with severe PTSD. The theme of the high frequency of non-fatal conditions was revealed with cases illustrating new diagnoses (a case with n=8 diagnoses), hospitalisations for new conditions (n=6), non-fatal injury events (n=3) and for sexually transmitted infections (n=3). The theme of chronic debility as a consequence of various conditions was illustrated with cases who had suffered from being gassed or having gastroenteritis, malaria or pandemic influenza. CONCLUSION: These 10 selected cases reiterate how severe and extensive the morbidity burden for military personnel in WWI could be. Also illustrated is how the morbidity could contribute to adverse impacts on some of their lives after returning to New Zealand.

Continued mitigation needed to minimise the high health burden from COVID-19 in Aotearoa New Zealand.

In this article we review the COVID-19 pandemic experience in Aotearoa New Zealand and consider the optimal ongoing response strategy. We note that this pandemic virus looks likely to result in future waves of infection that diminish in size over time, depending on such factors as viral evolution and population immunity. However, the burden of disease remains high with thousands of infections, hundreds of hospitalisations and tens of deaths each week, and an unknown burden of long-term illness (long COVID). Alongside this there is a considerable burden from other important respiratory illnesses, including influenza and RSV, that needs more attention. Given this impact and the associated health inequities, particularly for Maori and Pacific Peoples, we consider that an ongoing respiratory disease mitigation strategy is appropriate for New Zealand. As such, the previously described "vaccines plus" approach (involving vaccination and public health and social measures), should now be integrated with the surveillance and control of other important respiratory infections. Now is also a time for New Zealand to build on the lessons from the COVID-19 pandemic to enhance preparedness nationally and internationally. New Zealand's experience suggests elimination (or ideally exclusion) should be the default first choice for future pandemics of sufficient severity.

The unseen casualties of the First World War: insights from a randomly selected military sample.

AIMS: Studies of the morbidity burden of military personnel participating in the First World War (WWI) have tended to focus on specific outcomes (e.g., injuries). Therefore, we aimed for a more complete assessment. METHODS: From a random sample of active war service-exposed New Zealand WWI veterans used in previously published work, we examined a random subsample of 200 personnel. Data on diagnoses, hospitalisations and outcomes were extracted from the online archival military files. RESULTS: These personnel experienced a very high morbidity burden with 94% having at least one new condition diagnosed during their military service (mean: 2.4 per individual; range: 0 to 8). The relative severity of these conditions was reflected by the high level of hospitalisation (89% at least once; mean: 1.8 hospitalisations for new conditions per individual) and 59% of personnel being deemed no longer fit for military service at some stage. More of the new diagnoses were for infectious diseases than for conflict-related injuries (117 vs 50 cases per 100 personnel). Respiratory conditions such as influenza, pneumonia and tuberculosis affected 33% of personnel, and 14% were diagnosed with sexually transmitted infections. Diseases reflecting hazardous environmental conditions were relatively common e.g., for dysentery/gastroenteritis in 12% and scabies in 5% of personnel. Diagnoses suggestive of post-traumatic stress disorder (PTSD) were present in 10% and chemical warfare injuries in 6%. CONCLUSIONS: The overall morbidity burden of this military force in WWI was very high, and much higher than the previous official estimates.

Complex eco-evolutionary responses of a foundational coastal marsh plant to global change.

Predicting the fate of coastal marshes requires understanding how plants respond to rapid environmental change. Environmental change can elicit shifts in trait variation attributable to phenotypic plasticity and act as selective agents to shift trait means, resulting in rapid evolution. Comparably, less is known about the potential for responses to reflect the evolution of trait plasticity. Here, we assessed the relative magnitude of eco-evolutionary responses to interacting global change factors using a multifactorial experiment. We exposed replicates of 32 Schoenoplectus americanus genotypes 'resurrected' from century-long, soil-stored seed banks to ambient or elevated CO2 , varying levels of inundation, and the presence of a competing marsh grass, across two sites with different salinities. Comparisons of responses to global change factors among age cohorts and across provenances indicated that plasticity has evolved in five of the seven traits measured. Accounting for evolutionary factors (i.e. evolution and sources of heritable variation) in statistical models explained an additional 9-31% of trait variation. Our findings indicate that evolutionary factors mediate ecological responses to environmental change. The magnitude of evolutionary change in plant traits over the last century suggests that evolution could play a role in pacing future ecosystem response to environmental change.

Protecting school communities from COVID-19 and other infectious disease outbreaks: the urgent need for healthy schools in Aotearoa New Zealand.

Nil.

Tobacco endgame intervention impacts on health gains and Maori:non-Maori health inequity: a simulation study of the Aotearoa/New Zealand Tobacco Action Plan.

BACKGROUND: The Aotearoa/New Zealand Government is aiming to end the tobacco epidemic and markedly reduce Maori:non-Maori health inequalities by legislating: (1) denicotinisation of retail tobacco, (2) 95% reduction in retail outlets and (c) a tobacco free-generation whereby people born after 2005 are unable to legally purchase tobacco. This paper estimates future smoking prevalence, mortality inequality and health-adjusted life year (HALY) impacts of these strategies. METHODS: We used a Markov model to estimate future yearly smoking and vaping prevalence, linked to a proportional multistate life table model to estimate future mortality and HALYs. RESULTS: The combined package of strategies (plus media promotion) reduced adult smoking prevalence from 31.8% in 2022 to 7.3% in 2025 for Maori, and 11.8% to 2.7% for non-Maori. The 5% smoking prevalence target was forecast to be achieved in 2026 and 2027 for Maori males and females, respectively.The HALY gains for the combined package over the population's remaining lifespan were estimated to be 594 000 (95% uncertainty interval (UI): 443 000 to 738 000; 3% discount rate). Denicotinisation alone achieved 97% of these HALYs, the retail strategy 19% and tobacco-free generation 12%.By 2040, the combined package was forcat to reduce the gap in Maori:non-Maori all-cause mortality rates for people 45+ years old by 22.9% (95% UI: 19.9% to 26.2%) for females and 9.6% (8.4% to 11.0%) for males. CONCLUSION: A tobacco endgame strategy, especially denicotinisation, could deliver large health benefits and dramatically reduce health inequities between Maori and non-Maori in Aotearoa/New Zealand.

Comparing COVID-19 pandemic health responses in two high-income island nations: Iceland and New Zealand.

AIMS: We aimed to compare COVID-19 control measures, epidemiological characteristics and economic performance measures in two high-income island nations with small populations, favorable border control options, and relatively good outcomes: Iceland and New Zealand (NZ). METHODS: We examined peer-reviewed journal articles, official websites, reports, media releases and press articles for data on pandemic preparedness and COVID-19 public health responses from 1 January 2020 to 1 June 2022 in Iceland and NZ. We calculated epidemiological characteristics of the COVID-19 pandemic, as well as measures of economic performance. RESULTS: Both nations had the lowest excess mortality in the OECD from the start of the pandemic up to June 2022. Iceland pursued a mitigation strategy, never used lockdowns or officially closed its border to foreign nationals, and instead relied on extensive testing and contact tracing early in the pandemic. Meanwhile, NZ pursued an elimination strategy, used a strict national lockdown to stop transmission, and closed its international border to everyone except citizens and permanent residents going through quarantine and testing. Iceland experienced a larger decrease in gross domestic product in 2020 (relative to 2019) than NZ (-8·27% vs. -1·22%, respectively). In late 2021, NZ announced a shift to a suppression strategy and in 2022 began to reopen its border in stages, while Iceland ended all public restrictions on 25 February 2022. CONCLUSIONS: Many of Iceland's and NZ's pandemic control measures appeared successful and features of the responses in both countries could potentially be adopted by other jurisdictions to address future disease outbreaks and pandemic threats.

Disease-Related Loss to Government Funding: Longitudinal Analysis of Individual-Level Health and Tax Data for an Entire Country.

OBJECTIVES: The objective of this longitudinal analysis was to estimate funding loss in terms of tax revenue to the New Zealand (NZ) government from disease and injury among working age adults. METHODS: Linked national health and tax data sets of the usually resident population between 2006 and 2016 were used to model 40 disease states simultaneously in a fixed-effects regression analysis to estimate population-level tax loss from disease and injury. To estimate tax revenue loss to the NZ government, we modeled a counterfactual scenario where all disease/injury was cause deleted. RESULTS: The estimated tax paid by all 25- to 64-year-olds in the eligible NZ population was $15 773 million (m) per annum (US dollar 2021), or $16 446 m for a counterfactual as though no one had any disease disease-related income loss (a 4.3% or $672.9 m increase in tax revenue per annum). The disease that-if it had no impact on income-generated the greatest impact was mental illness, contributing 34.7% ($233.3 m) of all disease-related tax loss, followed by cardiovascular (14.7%, $99.0 m) and endocrine (10.2%, $68.8 m). Tax revenue gains after deleting all disease/injury increased up to 65 years of age, with the largest contributor occurring among 60- to 64-year-olds ($131.7 m). Varied results were also observed among different ethnicities and differing levels of deprivation. CONCLUSIONS: This study finds considerable variation by disease on worker productivity and therefore tax revenue in this high-income country. These findings strengthen the economic and government case for prevention, particularly the prevention of mental health conditions and cardiovascular disease.

Indoor air quality, largely neglected and in urgent need of a refresh.

Nil.

Imaging and plate counting to quantify the effect of an antimicrobial: A case study of a photo-activated chlorine dioxide treatment.

AIM: To assess removal versus kill efficacies of antimicrobial treatments against thick biofilms with statistical confidence. METHODS AND RESULTS: A photo-activated chlorine dioxide treatment (Photo ClO2 ) was tested in two independent experiments against thick (>100 µm) Pseudomonas aeruginosa biofilms. Kill efficacy was assessed by viable plate counts. Removal efficacy was assessed by 3D confocal scanning laser microscope imaging (CSLM). Biovolumes were calculated using an image analysis approach that models the penetration limitation of the laser into thick biofilms using Beer's Law. Error bars are provided that account for the spatial correlation of the biofilm's surface. The responsiveness of the biovolumes and plate counts to the increasing contact time of Photo ClO2 were quite different, with a massive 7 log reduction in viable cells (95% confidence interval [CI]: 6.2, 7.9) but a more moderate 73% reduction in biovolume (95% CI: [60%, 100%]). Results are leveraged to quantitatively assess candidate CSLM experimental designs of thick biofilms. CONCLUSIONS: Photo ClO2 kills biofilm bacteria but only partially removes the biofilm from the surface. To maximize statistical confidence in assessing removal, imaging experiments should use fewer pixels in each z-slice, and more importantly, at least two independent experiments even if there is only a single field of view in each experiment. SIGNIFICANCE AND IMPACT OF STUDY: There is limited penetration depth when collecting 3D confocal images of thick biofilms. Removal can be assessed by optimally fitting Beer's Law to all of the intensities in a 3D image and by accounting for the spatial correlation of the biofilm's surface. For thick biofilms, other image analysis approaches are biased or do not provide error bars. We generate unbiased estimates of removal and assess candidate CSLM experimental designs of thick biofilms with different pixilations, numbers of fields of view and number of experiments using the included design tool.

Modelling the impacts of tobacco denicotinisation on achieving the Smokefree 2025 goal in Aotearoa New Zealand.

AIM: To provide preliminary high-level modelling estimates of the impact of denicotinisation of tobacco on changes in smoking prevalence in Aotearoa New Zealand relative to the New Zealand Government's Smokefree 2025 goal. METHODS: An Excel spreadsheet was populated with smoking and vaping prevalence data from the New Zealand Health Survey and we projected business-as-usual trends. Using various parameters from the literature (New Zealand trial data, New Zealand EASE-ITC Study results), we modelled the potential impact of denicotinisation of tobacco (with no other tobacco permitted for sale) out to 2025. In addition to the base case (considered most likely), Scenario 1 used estimates from a published expert knowledge elicitation process, and Scenario 2 considered the addition of extra mass-media campaign and Quitline support to the base case. RESULTS: With the denicotinisation intervention, adult daily smoking prevalences were estimated to decline to under 5% by 2025 for the European/Other ethnic grouping (in the base case and both scenarios) and in one scenario (Scenario 1) for Maori (2.5%). However, prevalence did not fall below 5% in the base case for Maori (7.7%) or in Scenario 2 (5.2%). In the base case, vaping was estimated to increase to 7.9% in the adult population by 2025, and up to 10.7% in one scenario (Scenario 1). CONCLUSIONS: This preliminary high-level modelling suggests that mandated denicotinisation has a plausible chance of achieving the New Zealand Government's Smokefree 2025 goal. The probability of success would increase if supplemented with interventions such as mass-media campaigns offering Quitline support (especially if predominantly designed for a Maori audience). Nevertheless, there is much uncertainty with these results and more sophisticated modelling is forthcoming.

Updated Health and Cost Impacts of Electronic Nicotine Delivery Systems, Using Recent Estimates of Relative Harm for Vaping Compared to Smoking.

BACKGROUND: Measuring population health and costs effects of liberalizing access to electronic nicotine delivery systems (ENDS) is an evolving field with high persisting uncertainty. A critical area of uncertainty for policy-makers are estimates of net harms from ENDS relative to cigarettes, therefore, we model these harms using updated estimates incorporating disease specificity. METHODS: We use updated estimates of relative harm of vaping vs smoking, based upon relevant biomarker studies to model the impact of liberalizing access to ENDS in New Zealand (NZ), relative to a ban (where ENDS are not legally available), in an existing proportional multi-state life-table model of 16 tobacco-related diseases. RESULTS: This modeling suggests that ENDS liberalization results in an expected gain of 195 000 quality-adjusted life-years (QALYs) over the remainder of the NZ population's lifespan. There was wide uncertainty in QALYs gained (95% uncertainty interval [UI] = -8000 to 406 000) with a 3.2% probability of net health loss (based upon the number of simulation runs returning positive QALY gains). The average per capita health gain was 0.044 QALYs (equivalent to an extra 16 days of healthy life). Health system cost-savings were expected to be NZ$2.8 billion (US$2.1 billion in 2020 US$; 95%UI: -0.3 to 6.2 billion [2011 NZ$]), with an estimated 3% chance of a net increase in per capita cost. CONCLUSIONS: This updated modeling around liberalizing ENDs in NZ, still suggests likely net health and cost-saving benefits-but of lesser magnitude than previous work and with a small possibility of net harm to population health. IMPLICATIONS: This study found evidence using updated biomarker studies that ENDS liberalization could result in QALY gains across the New Zealand population lifespan that are also cost-saving to the health system. Governments should include the information from these types of modeling studies in their decision-making around potentially improving access to ENDS for existing smokers, while at the same further reducing access to tobacco.

Accounting for variability when resurrecting dormant propagules substantiates their use in eco-evolutionary studies.

There has been a steady rise in the use of dormant propagules to study biotic responses to environmental change over time. This is particularly important for organisms that strongly mediate ecosystem processes, as changes in their traits over time can provide a unique snapshot into the structure and function of ecosystems from decades to millennia in the past. Understanding sources of bias and variation is a challenge in the field of resurrection ecology, including those that arise because often-used measurements like seed germination success are imperfect indicators of propagule viability. Using a Bayesian statistical framework, we evaluated sources of variability and tested for zero-inflation and overdispersion in data from 13 germination trials of soil-stored seeds of Schoenoplectus americanus, an ecosystem engineer in coastal salt marshes in the Chesapeake Bay. We hypothesized that these two model structures align with an ecological understanding of dormancy and revival: zero-inflation could arise due to failed germinations resulting from inviability or failed attempts to break dormancy, and overdispersion could arise by failing to measure important seed traits. A model that accounted for overdispersion, but not zero-inflation, was the best fit to our data. Tetrazolium viability tests corroborated this result: most seeds that failed to germinate did so because they were inviable, not because experimental methods failed to break their dormancy. Seed viability declined exponentially with seed age and was mediated by seed provenance and experimental conditions. Our results provide a framework for accounting for and explaining variability when estimating propagule viability from soil-stored natural archives which is a key aspect of using dormant propagules in eco-evolutionary studies.

Improving on estimates of the potential relative harm to health from using modern ENDS (vaping) compared to tobacco smoking.

BACKGROUND: Although the harm to health from electronic nicotine delivery systems (ENDS) compared to smoked tobacco remains highly uncertain, society and governments still need to know the likely range of the relative harm to inform regulatory policies for ENDS and smoking. METHODS: We identified biomarkers with specificity of association with different disease groupings e.g., volatile organic compound (VOCs) for chronic obstructive pulmonary disease; and tobacco-specific N´-nitrosamines (TSNAs) and polycyclic aromatic hydrocarbons (PAHs) for all cancers. We conducted a review of recent studies (post January 2017) that compared these biomarkers between people exclusively using ENDS and those exclusively smoking tobacco. The percentage differences in these biomarkers, weighted by study size and adjusted for acrolein from other sources, were used as a proxy for the assumed percentage difference in disease harm between ENDS and smoking. These relative differences were applied to previously modelled estimates of smoking-related health loss (in health-adjusted life-years; HALYs). RESULTS: The respective relative biomarker levels (ENDS vs smoking) were: 28% for respiratory diseases (five results, three studies); 42% for cancers (five results, four studies); and 35% for cardiovascular (seven results, four studies). When integrated with the HALY impacts by disease, the overall harm to health from ENDS was estimated to be 33% that of smoking. CONCLUSIONS: This analysis, suggests that the use of modern ENDS devices (vaping) could be a third as harmful to health as smoking in a high-income country setting. But this estimate is based on a limited number of biomarker studies and is best be considered a likely upper level of ENDS risk given potential biases in our method (i.e., the biomarkers used being correlated with more unaccounted for toxicants in smoking compared to with using ENDS).

Failures of quarantine systems for preventing COVID-19 outbreaks in Australia and New Zealand.

OBJECTIVES: To identify COVID-19 quarantine system failures in Australia and New Zealand. DESIGN, SETTING, PARTICIPANTS: Observational epidemiological study of travellers in managed quarantine in Australia and New Zealand, to 15 June 2021. MAIN OUTCOME MEASURES: Number of quarantine system failures, and failure with respect to numbers of travellers and SARS-CoV-2-positive travellers. RESULTS: We identified 22 quarantine system failures in Australia and ten in New Zealand to 15 June 2021. One failure initiated a COVID-19 outbreak that caused more than 800 deaths (the Victorian "second wave"); nine lockdowns were linked with quarantine system failures. The failure risk was estimated to be 5.0 failures per 100 000 travellers passing through quarantine and 6.1 (95% CI, 4.0-8.3) failures per 1000 SARS-CoV-2-positive travellers. The risk per 1000 SARS-CoV-2-positive travellers was higher in New Zealand than Australia (relative risk, 2.0; 95% CI, 1.0-4.2). CONCLUSIONS: Quarantine system failures can be costly in terms of lives and economic impact, including lockdowns. Our findings indicate that infection control in quarantine systems in Australia and New Zealand should be improved, including vaccination of quarantine workers and incoming travellers, or that alternatives to hotel-based quarantine should be developed.

A century-long record of plant evolution reconstructed from a coastal marsh seed bank.

Evidence is mounting that climate-driven shifts in environmental conditions can elicit organismal evolution, yet there are sparingly few long-term records that document the tempo and progression of responses, particularly for plants capable of transforming ecosystems. In this study, we "resurrected" cohorts of a foundational coastal marsh sedge (Schoenoplectus americanus) from a time-stratified seed bank to reconstruct a century-long record of heritable variation in response to salinity exposure. Common-garden experiments revealed that S. americanus exhibits heritable variation in phenotypic traits and biomass-based measures of salinity tolerance. We found that responses to salinity exposure differed among the revived cohorts, with plants from the early 20th century exhibiting greater salinity tolerance than those from the mid to late 20th century. Fluctuations in salinity tolerance could reflect stochastic variation but a congruent record of genotypic variation points to the alternative possibility that the loss and gain in functionality are driven by selection, with comparisons to historical rainfall and paleosalinity records suggesting that selective pressures vary according to shifting estuarine conditions. Because salinity tolerance in S. americanus is tightly coupled to primary productivity and other vital ecosystem attributes, these findings indicate that organismal evolution merits further consideration as a factor shaping coastal marsh responses to climate change.

Bumper issue of COVID-19 pandemic studies of relevance to Aotearoa New Zealand.

In response to the COVID-19 pandemic, Aotearoa New Zealand adopted a clear 'elimination strategy', which has (up to June 2021) been very successful in both health and economic terms compared to other OECD countries. Nevertheless, the pandemic response has still been a very major shock to the New Zealand health system. This issue of the New Zealand Medical Journal has 14 new pandemic-related articles. Some of this work can help inform vaccination prioritisation decisions and inform preparations of primary and secondary care services and social services for any future raising of levels in the pandemic Alert Level system. Particularly strong themes are around the value (and challenges) of telehealth services, and also the need for responses throughout the health system to ensure health equity and support for the most vulnerable citizens.

Should prioritising health interventions be informed by modelling studies? The case of cancer control in Aotearoa New Zealand.

In this viewpoint, we suggest that policymakers should prioritise health interventions by using evidence around health gain, impact on equity, health-system costs and cost-effectiveness. We take the example of the new cancer control agency in New Zealand, Te Aho o Te Kahu, and argue that its decision-making can now be informed by many methodologically compatible epidemiological and health economic analyses. These analyses span primary prevention of cancer (eg, tobacco control, dietary and physical activity interventions and HPV vaccination), cancer screening, cancer treatment and palliative care. The largest health gain and cost-savings from the available modelling work for New Zealand are seen in nutrition and tobacco control interventions in particular. Many of these interventions have potentially greater per capita health gain for Maori than non-Maori and are also found to be cost saving for the health sector. In summary, appropriate prioritisation of interventions can potentially both maximise health benefits as well as making best use of government funding of the health system.

Stereotactic ablative body radiotherapy in patients with oligometastatic cancers: a prospective, registry-based, single-arm, observational, evaluation study.

BACKGROUND: Stereotactic ablative body radiotherapy (SABR) is increasingly being used to treat oligometastatic cancers, but high-level evidence to provide a basis for policy making is scarce. Additional evidence from a real-world setting is required. We present the results of a national study of patients with extracranial oligometastases undergoing SABR, representing the largest dataset, to our knowledge, on outcomes in this population so far. METHODS: In 2015, National Health Service (NHS) England launched a Commissioning through Evaluation scheme that funded a prospective, registry-based, single-arm, observational, evaluation study of patients with solid cancer and extracranial oligometastases treated with SABR. Prescribed doses ranged from 24-60 Gy administered in three to eight fractions. The study was done at 17 NHS radiotherapy centres in England. Patients were eligible for the scheme if aged 18 years or older with confirmed primary carcinoma (excluding haematological malignancies), one to three extracranial metastatic lesions, a disease-free interval from primary tumour development to metastases of longer than 6 months (with the exception of synchronous colorectal liver metastases), a WHO performance status of 2 or lower, and a life expectancy of at least 6 months. The primary outcome was overall survival at 1 year and 2 years from the start of SABR treatment. The study is now completed. FINDINGS: Between June 15, 2015, and Jan 30, 2019, 1422 patients were recruited from 17 hospitals in England. The median age of the patients was 69 years (IQR 62-76), and the most common primary tumour was prostate cancer (406 [28·6%] patients). Median follow-up was 13 months (IQR 6-23). Overall survival was 92·3% (95% CI 90·5-93·9) at 1 year and 79·2% (76·0-82·1) at 2 years. The most common grade 3 adverse event was fatigue (28 [2·0%] of 1422 patients) and the most common serious (grade 4) event was increased liver enzymes (nine [0·6%]). Notreatment-related deaths were reported. INTERPRETATION: In patients with extracranial oligometastatic cancer, use of SABR was associated with high overall survival and low toxicity. 'The study findings complement existing evidence from a randomised, phase 2 trial, and represent high-level, real-world evidence supporting the use of SABR in this patient cohort, with a phase 3 randomised, controlled trial to confirm these findings underway. Based on the selection criteria in this study, SABR was commissioned by NHS England in March, 2020, as a treatment option for patients with oligometastatic disease. FUNDING: NHS England Commissioning through Evaluation scheme.