An evaluation of the COVID-19 self-service digital contact tracing system in New Zealand.

BACKGROUND: Digital contact tracing (DCT) aims to improve time-to-isolation (timeliness) and find more potentially exposed individuals (sensitivity) to enhance the utility of contact tracing. The aim of this study was to evaluate the public uptake of a DCT self-service survey and its integration with the Bluetooth exposure notification system within the New Zealand Covid Tracer App (NZCTA). METHODS: We adopted a retrospective cohort study design using community COVID-19 cases from February 2022 to August 2022 in New Zealand (1.2 million cases). We examined the proportion of cases completing a self-service survey and the time to complete the survey by age, sex and ethnicity. RESULTS: Overall, 66 % of cases completed their self-service survey. Completion was influenced by age, sex and ethnicity. The median completion time was 1.8 h (IQR 0.2, 17.2), with 95 % of those completing this survey doing so within 48 h of case identification. Around 13 % of all survey completers also uploaded their Bluetooth data, which resulted in an average of 663 cases per day notifying 4.5 contacts per case. CONCLUSION: The combination of high public uptake and rapid response times suggest self-service DCT could be a useful tool for future outbreaks, particularly if implemented in conjunction with manual processes and other DCT tools (e.g. Bluetooth) to address issues related to performance (sensitivity, timeliness), effectiveness, and health equity.

Population and contact tracer uptake of New Zealand's QR-code-based digital contact tracing app for COVID-19.

This study aimed to understand the population and contact tracer uptake of the quick response (QR)-code-based function of the New Zealand COVID Tracer App (NZCTA) used for digital contact tracing (DCT). We used a retrospective cohort of all COVID-19 cases between August 2020 and February 2022. Cases of Asian and other ethnicities were 2.6 times (adjusted relative risk (aRR) 2.58, 99 per cent confidence interval (95% CI) 2.18, 3.05) and 1.8 times (aRR 1.81, 95% CI 1.58, 2.06) more likely than Maori cases to generate a token during the Delta period, and this persisted during the Omicron period. Contact tracing organization also influenced location token generation with cases handled by National Case Investigation Service (NCIS) staff being 2.03 (95% CI 1.79, 2.30) times more likely to generate a token than cases managed by clinical staff at local Public Health Units (PHUs). Public uptake and participation in the location-based system independent of contact tracer uptake were estimated at 45%. The positive predictive value (PPV) of the QR code system was estimated to be close to nil for detecting close contacts but close to 100% for detecting casual contacts. Our paper shows that the QR-code-based function of the NZCTA likely made a negligible impact on the COVID-19 response in New Zealand (NZ) in relation to isolating potential close contacts of cases but likely was effective at identifying and notifying casual contacts.

Barriers to adopting digital contact tracing for COVID-19: Experiences in New Zealand.

BACKGROUND: Digital contact tracing (DCT) was a central component of the global response to containing COVID-19. Research has raised concerns that DCT could exacerbate inequities, yet the experiences of diverse communities at greater risk from COVID-19 are typically underrepresented. METHODS: The present study aimed to understand the perceived barriers to the adoption of the app amongst Maori, Pasifika, and disabled people. Focus groups and interviews were undertaken with Maori, Pasifika, and disability sector stakeholders and community participants. RESULTS: Participants (n = 34) generally expressed willingness to utilise DCT and support its adoption within the communities. Simultaneously, participants revealed how the app could marginalise community members who struggled with the usability and those distrusting of the government's COVID-19 interventions. CONCLUSIONS: The findings highlight how addressing communication inequality can assist in the development of contact-tracing responses that are both effective and equitable. The study provides insights about the role of information and communication technologies as health resources. PATIENT OR PUBLIC CONTRIBUTION: Consulting with members of the target communities was central throughout the present study, including recommendations for potential participants, participation in interviews and sharing early findings for feedback. This study reports on focus groups and interviews with individuals from Maori and disability sectors.

The estimated health impact of alcohol interventions in New Zealand: A modelling study.

AIMS: To estimate the health impacts of key modelled alcohol interventions among Maori (indigenous peoples) and non-Maori in New Zealand (NZ). DESIGN: Multi-stage life-table intervention modelling study. We modelled two scenarios: (1) business-as-usual (BAU); and (2) an intervention package scenario that included a 50% alcohol tax increase, outlet density reduction from 63 to five outlets per 100 000 people, outlet hours reduction from 112 to 50 per week and a complete ban on all forms of alcohol marketing. SETTING AND PARTICIPANTS: The model's population replicates the 2018 NZ population by ethnicity (Maori/non-Maori), age and sex. MEASUREMENTS: Alcohol consumption was estimated using nationally representative survey data combined with sales data and corrected for tourist and unrecorded consumption. Disease incidence, prevalence and mortality were calculated using Ministry of Health data. We used dose-response relationships between alcohol and illness from the 2016 Global Burden of Disease study and calculated disability rates for each illness. Changes in consumption were based on the following effect sizes: total intervention package [-30.3%, standard deviation (SD) = 0.02); tax (-7.60%, SD = 0.01); outlet density (-8.64%, SD = 0.01); outlet hours (-9.24%, SD = 0.01); and marketing (-8.98%, SD = 0.02). We measured health gain using health-adjusted life years (HALYs) and life expectancy. FINDINGS: Compared with the BAU scenario, the total alcohol intervention package resulted in 726 000 [95% uncertainty interval (UI) = 492 000-913 000] HALYs gained during the life-time of the modelled population. Maori experienced greater HALY gains compared with non-Maori (0.21, 95% UI = 0.14-0.26 and 0.16, 95% UI = 0.11-0.20, respectively). When modelled individually, each alcohol intervention within the intervention package produced similar health gains (~200 000 HALYs per intervention) owing to the similar effect sizes. CONCLUSIONS: Modelled interventions for increased alcohol tax, reduced availability of alcohol and a ban on alcohol marketing among Maori and non-Maori in New Zealand (NZ) suggest substantial population-wide health gains and reduced health inequities between Maori and non-Maori.

Body appreciation around the world: Measurement invariance of the Body Appreciation Scale-2 (BAS-2) across 65 nations, 40 languages, gender identities, and age.

The Body Appreciation Scale-2 (BAS-2) is a widely used measure of a core facet of the positive body image construct. However, extant research concerning measurement invariance of the BAS-2 across a large number of nations remains limited. Here, we utilised the Body Image in Nature (BINS) dataset - with data collected between 2020 and 2022 - to assess measurement invariance of the BAS-2 across 65 nations, 40 languages, gender identities, and age groups. Multi-group confirmatory factor analysis indicated that full scalar invariance was upheld across all nations, languages, gender identities, and age groups, suggesting that the unidimensional BAS-2 model has widespread applicability. There were large differences across nations and languages in latent body appreciation, while differences across gender identities and age groups were negligible-to-small. Additionally, greater body appreciation was significantly associated with higher life satisfaction, being single (versus being married or in a committed relationship), and greater rurality (versus urbanicity). Across a subset of nations where nation-level data were available, greater body appreciation was also significantly associated with greater cultural distance from the United States and greater relative income inequality. These findings suggest that the BAS-2 likely captures a near-universal conceptualisation of the body appreciation construct, which should facilitate further cross-cultural research.

The nature and extent of outdoor alcohol marketing in Wellington, New Zealand: a longitudinal audit and spatio-temporal analysis of outdoor alcohol marketing.

AIM: exposure to alcohol marketing is associated with increased consumption. We aimed to (i) measure the nature and extent of outdoor alcohol marketing within a high-density urban neighbourhood and (ii) examine temporal and spatial trends in alcohol marketing. METHODS: this study used a longitudinal design to monitor paid advertising in public spaces over two 10-week periods in Wellington, New Zealand (Nov-Jan 2020-2021, Nov-Jan 2021-2022). The data were collected on-foot following an established route once a week using a phone camera, which also recorded gps data of ad locations. Temporal and spatial trends in alcohol ad prevalence were assessed. RESULTS: over the study period, 13% (n = 1619) of all ads (n = 12,472) were for alcohol. Alcohol ads were predominately for spirits (29%), ready-to-drink (27%) and beer (23%). Almost half of all alcohol ads (49%) did not contain a responsible consumption message, while those with a message were de-emphasized relative to promotional features. A temporal trend was observed in 2020, whereby alcohol marketing decreased over the summer, but this trend was not reflected in 2021. Alcohol ads were more likely than non-alcohol ads to be placed in premium positions on roads of high pedestrian and motor vehicle traffic. CONCLUSION: alcohol marketing is common in urban centres. Local and central government policy could substantially reduce the levels of alcohol marketing exposure via outdoor marketing.

The potential human health hazard of nitrates in drinking water: a media discourse analysis in a high-income country.

BACKGROUND: Recent studies linking low levels of nitrate in drinking water to colorectal cancer have raised public concerns over nitrate contamination. The aim of this study was to analyze the media discourse on the potential human health hazard of nitrates in drinking water in a high-income country with a large livestock industry: New Zealand (NZ). METHODS: Searches of media sources ("major newspapers") held by the Factiva database for the NZ setting in the five-year period 17 December 2016 to 20 December 2021. RESULTS: The largest number of media items was observed for 2017 (n = 108), the year of a NZ general election, with a notable decrease in 2020 (n = 20) that was likely due to the Covid-19 pandemic, which dominated health media. However, the percentage of these media items with a health focus steadily increased over time, from 11.1% of all articles in 2017 to 51.2% in 2021. The most commonly mentioned health hazard was colorectal cancer, followed by methemoglobinemia. The temporal pattern of media items suggests that the release of scientific studies and scholarly blogs was associated with the publication of subsequent media items. Major stakeholders involved in the discourse included representatives of local and central government, environmental and recreational interest groups, researchers, local residents, agricultural interest groups, and health organizations. Maori (Indigenous New Zealanders) values or perspectives were rarely mentioned. CONCLUSIONS: Analysis of major newspapers for a five-year period indicated that a wide range of expert comment and opinions were made available to the public and policy makers on the issue of nitrates in water. While many different stakeholder views were captured in the media discourse, there is scope for the media to better report the views of Maori on this topic. There is also a need for articles detailing the health issues to also refer to the environmental, recreational, and cultural aspects of protecting water quality to ensure that the public, policy makers, and regulators are aware of co-benefits.

Pilot of a digital contact tracing card in a hospital setting in New Zealand, 2020.

Countries are rapidly developing digital contact tracing solutions to augment manual contact tracing. There is limited empirical evidence evaluating these tools. We conducted a feasibility study of a Bluetooth-enabled card with hospital staff in New Zealand (n = 42). We compared the card data against self-report contact surveys and a stronger Bluetooth device. The cards detected substantially more contacts than self-report contact surveys, while the concordance between Bluetooth devices was high, suggesting that the cards detected clinically relevant close contacts. There was high acceptability among participants, suggesting that their integration would be accepted by healthcare staff. As the pandemic shifts, there is a need to rapidly contact trace and conduct informed risk management, particularly in critical settings such as healthcare.

An assessment of compliance with optimal fluoride levels for oral health benefit by New Zealand drinking water suppliers.

OBJECTIVES: Community water fluoridation (CWF) has proven oral health benefits. We investigated whether drinking water suppliers are meeting New Zealand CWF targets (0.7-1.0 ppm) to ensure these benefits. METHODS: We retrieved fluoride testing data from 25 supplies serving 2,059,000 people (82% of people on a fluoridated supply), for the years 1992-2022 (22,220 weekly observations). We descriptively assessed compliance with fluoride targets in this convenience sample. RESULTS: The mean fluoride level was 0.66 ppm (SD 0.28). Water suppliers achieved fluoride targets 54.1% of the time (range 4.2%-77.9%). Fluoride concentration fell short of the target in 42.2% of observations, exceeded but under the maximum acceptable value (MAV) in 3.6%, and in excess of the MAV in 0.1%. The percentage of compliant observations was greater in larger than smaller supplies. CONCLUSIONS: Noncompliance with CWF targets was common. Epidemiological studies that rely on fluoridation status as their exposure may underestimate the oral health benefits of CWF. Our results highlight future challenges with the feasibility of expanding CWF under new legislation as well as the weaknesses in drinking water surveillance.

Beyond muddy waters: Three Waters reforms required to future-proof water service delivery and protect public health in Aotearoa New Zealand.

A 2016 drinking water-related campylobacteriosis outbreak in Aotearoa New Zealand made much of an entire town sick leading to reforms colloquially called "Three Waters", which aims to improve the management and delivery of waste, storm and drinking water systems. Public discourse on the Three Waters reforms has been dominated by anti-co-governance rhetoric, concerns around privatisation and loss of local control and alternative less comprehensive reform models. This debate has drowned out the fundamental problem statement justifying the reforms, that is, the management of drinking water resources is currently: 1) demonstrably inadequate to protect public health and promote health equity; and 2) economically inefficient. We discuss four areas where the proposed Three Waters reforms are likely to address current and future challenges and improve public health. We conclude by outlining four areas of remaining contention.

Children's perspectives on the wicked problem of child poverty in Aotearoa New Zealand: a wearable camera study.

AIM: Child poverty is a wicked problem and a key determinant of health, but research on child poverty has relied largely on self-report methods and reports from parents or caregivers. In this study we aimed to assess aspects of child poverty using data collected by children using wearable cameras. METHOD: The Kids'Cam Project recruited 168 randomly selected children aged 11-13 from 16 randomly selected schools in the Wellington Region of Aotearoa New Zealand. Each child wore a wearable camera for four consecutive days, recording an image every seven seconds. We used negative binomial regression models to compare measures of household resources, harms, behaviours and built environment characteristics between children living in low socio-economic deprivation households (n=52) and children living in high socio-economic deprivation households (n=26). RESULTS: Compared with children living in conditions of low socio-economic deprivation, children living in conditions of high socio-economic deprivation captured significantly fewer types of fruit (RR=0.46), vegetables (RR=0.25), educational materials (RR = 0.49) and physical activity equipment (RR = 0.66) on camera. However, they lived in homes with more structural deficiencies (RR=4.50) and mould (no mould was observed in low socio-economic deprivation households). They were also less likely to live in households with fixed heating (RR=0.27) and home computers (RR=0.45), and more likely to consume non-core food outside home (RR=1.94). CONCLUSIONS: The children in this study show that children in poverty face disadvantages across many aspects of their lives. Comprehensive policies are urgently needed to address the complex problem of child poverty.

Expert insights on digital contact tracing: interviews with contact tracing policy professionals in New Zealand.

Digital contact tracing (DCT) is the application of digital tools to assist with identifying and informing close contacts of a COVID-19 case. DCT is a potential solution to capacity constraints of current manual contact tracing processes. Expert opinion from contact tracing professionals rarely informs public discourse on the benefits and limitations of DCT solutions. Three focus groups were undertaken in New Zealand to understand benefits and limitations of DCT solutions from contact tracing professionals. One was with the National Investigation and Tracing Centre (NITC) and two were with Public Health Units (PHUs). Participants highlighted four key themes including: (i) equity, (ii) privacy, (iii) communication and public perception and (iv) the operational model. Participants were concerned DCT solutions could exacerbate existing health inequities due to lack of access to, or familiarity with, technology. Poor communication and public understanding of DCT were seen as a major threat to both the efficacy of DCT solutions and the wider COVID-19 response. Most importantly, end-users were cautious of the operational model for DCT data that might: (i) attempt to replace manual processes that cannot or should not be automated by technology (case investigations, follow-ups); (ii) place undue burden on citizens and (iii) increase the workload for the current system beyond its capacity, for unproven or limited benefit. To be effective, contact tracing professionals believed DCT technologies must have strong privacy safeguards, a clear and simple communication strategy, interoperability with the existing contact tracing system and a foundation of health equity.

The distribution of harmful product marketing in public outdoor spaces and the effectiveness of marketing bans.

Children's exposure to the marketing of harmful products in public outdoor spaces may influence their consumption of those products and affect health into adulthood. This study aimed to: i) examine the spatial distribution of children's exposure to three types of marketing-related 'harms' (alcohol, unhealthy food, and gambling) in outdoor spaces in the Wellington region, New Zealand/Aotearoa; ii) compare differences in the distribution of harms by socioeconomic deprivation; and iii) estimate the effectiveness of different policies that ban such marketing. Data were from 122 children aged 11-13y who wore wearable cameras and GPS devices for four consecutive days from July 2014 to June 2015. Images were analysed to identify harmful product marketing exposures in public outdoor spaces. Eight policy scenarios were examined to identify the effectiveness of marketing bans, for all children and by socioeconomic deprivation. Children's ratio of harmful marketing was higher for children from high deprivation households and was also found to cluster, with hots spots observed around city centers. The effectiveness of marketing bans depended on the target setting and ban area, with banning 400 m around bus stops leading to the largest reduction. Effectiveness varied also by type of harm and socioeconomic deprivation. For example, banning alcohol marketing in residential areas was estimated to have a larger effect on exposure reduction for children from high deprivation households. Our findings suggest that alcohol, unhealthy food and gambling marketing often cluster outdoors and that targeted bans of such marketing would likely improve child health and, for some banning scenarios, promote equity.

A Case Study of Bluetooth Technology as a Supplemental Tool in Contact Tracing.

We present results from a 7-day trial of a Bluetooth-enabled card by the New Zealand Ministry of Health to investigate its usefulness in contact tracing. A comparison of the card with traditional contact tracing, which relies on self-reports of contacts to case investigators, demonstrated significantly higher levels of internal consistency in detected contact events by Bluetooth-enabled cards with 88% of contact events being detected by both cards involved in an interaction as compared to 64% for self-reports of contacts to case investigators. We found no clear evidence of memory recall worsening in reporting contact events that were further removed in time from the date of a case investigation. Roughly 66% of contact events between trial participants that were indicated by cards went unreported to case investigators, simultaneously highlighting the shortcomings of traditional contact tracing and the value of Bluetooth technology in detecting contact events that may otherwise go unreported. At the same time, cards detected only 65% of self-reported contact events, in part due to increasing non-compliance as the study progressed. This would suggest that Bluetooth technology can only be considered as a supplemental tool in contact tracing and not a viable replacement to traditional contact tracing unless measures are introduced to ensure greater compliance.

Nitrate contamination in drinking water and colorectal cancer: Exposure assessment and estimated health burden in New Zealand.

BACKGROUND: Epidemiological evidence in multiple jurisdictions has shown an association between nitrate exposure in drinking water and an increased risk of colorectal cancer (CRC). OBJECTIVE: We aimed to review the extent of nitrate contamination in New Zealand drinking water and estimate the health and financial burden of nitrate-attributable CRC. METHODS: We collated data on nitrate concentrations in drinking water for an estimated 85% of the New Zealand population (∼4 million people) who were on registered supplies. We estimated nitrate levels for the remaining population (∼600,000 people) based on samples from 371 unregistered (private) supplies. We used the effective rate ratio from previous epidemiological studies to estimate CRC cases and deaths attributable to nitrate in drinking water. RESULTS: Three-quarters of New Zealanders are on water supplies with less than 1 mg/L NO3-N. The population weighted average for nitrate exposure for people on registered supplies was 0.49 mg/L NO3-N with 1.91% (95%CI 0.49, 3.30) of CRC cases attributable to nitrates. This correlates to 49.7 cases per year (95%CI 14.9, 101.5) at a cost of 21.3 million USD (95% 6.4, 43.5 million USD). When combining registered and unregistered supplies, we estimated 3.26% (95%CI 0.84, 5.57) of CRC cases were attributable to nitrates, resulting in 100 cases (95%CI 25.7, 171.3) and 41 deaths (95%CI 10.5, 69.7) at a cost of 43.2 million USD (95%CI 10.9, 73.4). CONCLUSION: A substantial minority of New Zealanders are exposed to high or unknown levels of nitrates in their drinking water. Given the international epidemiological studies showing an association between cancer and nitrate ingestion from drinking water, this exposure may cause an important burden of preventable CRC cases, deaths, and economic costs. We consider there is sufficient evidence to justify a review of drinking water standards. Protecting public health adds to the strong environmental arguments to improve water management in New Zealand.

Quantifying the nitrate levels in bottled water in New Zealand.

OBJECTIVE: There is growing epidemiological evidence linking nitrate contamination to adverse health outcomes. Health concerns may drive consumers towards bottled water, however, nitrate levels in bottled water are not readily available. METHODS: We tested water samples from the 10 most popular brands using a TriOS OPUS UV optical nitrate sensor. RESULTS: Overall, all bottled water brands tested returned nitrate levels below 4.4 mg/L NO3. CONCLUSIONS: The growing health concerns associated with nitrate contamination suggest that increased reporting of water quality is required. IMPLICATIONS FOR PUBLIC HEALTH: Mandatory reporting of water quality laboratory reports by bottled water producers would improve transparency to consumers and help public health researchers track potential threats to water quality as new evidence emerges.

New Zealand's Climate Change Commission report: the critical need to address the missing health co-benefits of reducing emissions.

The Climate Change Commission's draft report and recommendations provide a pathway towards achieving the New Zealand Government's commitment to net zero emissions by 2050. However, the Commission has not adequately considered the health co-benefits of climate change mitigation. In this viewpoint, we assess how the Commission has considered health co-benefits in the key response domains. Extrapolating UK evidence to the New Zealand context suggests climate change mitigation strategies that reduce air pollution, transition the population towards plant-based diets and increase physical activity via active transport could prevent thousands of deaths per year in coming decades. Substantial health co-benefits would also arise from improved housing, cleaner water, noise reductions, afforestation and more compact cities. The Commission's draft report only briefly mentions many of these health co-benefits, and some are completely absent. We recommend the Commission's final report: (i) use health co-benefits as an explicit frame; (ii) ensure the government's Treaty of Waitangi obligations are met in all the domains covered to maximise benefits for Maori health and wellbeing; (iii) build on the successful COVID-19 response that demonstrated rapid, science-informed and vigorous government action can address major global health threats; (iv) include both public health expertise and Maori health expertise among its commissioners; (v) explain how health co-benefits are likely to generate major cost-savings to the health system.