How Do Past Immunization Strategies Compare With the COVID-19 Immunization Rollout: A New Zealand Analysis.

OBJECTIVE: The aim of this study was to compare past New Zealand immunization strategies with the New Zealand coronavirus disease 2019 (COVID-19) immunization roll-out. METHODS: Using the READ document analysis method, 2 New Zealand immunization strategies (for influenza and measles) were analyzed for how the disease, context, vaccine supply and demand, ethical principles (equity, individual autonomy, and maximizing benefits), and the Treaty of Waitangi impacted the immunization programs. The findings were compared with the ongoing COVID-19 mass immunization program in New Zealand, as of October 15, 2021. RESULTS: Several themes common to the case-studies and the COVID-19 pandemic were identified including the importance of equity, obligations under the Treaty of Waitangi, ethical mandates, and preparedness. CONCLUSIONS: Future emergency planning should integrate learnings from other infectious disease responses and immunization programs to avoid repeating mistakes and to create better health outcomes. This study has provided a basis for ongoing research into how an appropriate immunization plan can be developed that incorporates ethical values, the Treaty of Waitangi (in the NZ context), and evidence-based research to increase trust, equity, health, and preparedness for future outbreaks.

Adapting an equity-focused implementation process framework with a focus on ethnic health inequities in the Aotearoa New Zealand context.

BACKGROUND: Health intervention implementation in Aotearoa New Zealand (NZ), as in many countries globally, usually varies by ethnicity. Maori (the Indigenous peoples of Aotearoa) and Pacific peoples are less likely to receive interventions than other ethnic groups, despite experiencing persistent health inequities. This study aimed to develop an equity-focused implementation framework, appropriate for the Aotearoa NZ context, to support the planning and delivery of equitable implementation pathways for health interventions, with the intention of achieving equitable outcomes for Maori, as well as people originating from the Pacific Islands. METHODS: A scoping review of the literature to identify existing equity-focused implementation theories, models and frameworks was undertaken. One of these, the Equity-based framework for Implementation Research (EquIR), was selected for adaptation. The adaptation process was undertaken in collaboration with the project's Maori and consumer advisory groups and informed by the expertise of local health equity researchers and stakeholders, as well as the international implementation science literature. RESULTS: The adapted framework's foundation is the principles of Te Tiriti o Waitangi (the written agreement between Maori rangatira (chiefs) and the British Crown), and its focus is whanau (extended family)-centred implementation that meets the health and wellbeing aspirations, priorities and needs of whanau. The implementation pathway comprises four main steps: implementation planning, pathway design, monitoring, and outcomes and evaluation, all with an equity focus. The pathway is underpinned by the core constructs of equitable implementation in Aotearoa NZ: collaborative design, anti-racism, Maori and priority population expertise, cultural safety and values-based. Additionally, the contextual factors impacting implementation, i.e. the social, economic, commercial and political determinants of health, are included. CONCLUSIONS: The framework presented in this study is the first equity-focused process-type implementation framework to be adapted for the Aotearoa NZ context. This framework is intended to support and facilitate equity-focused implementation research and health intervention implementation by mainstream health services.

A scoping review of equity-focused implementation theories, models and frameworks in healthcare and their application in addressing ethnicity-related health inequities.

BACKGROUND: Inequities in implementation contribute to the unequal benefit of health interventions between groups of people with differing levels of advantage in society. Implementation science theories, models and frameworks (TMFs) provide a theoretical basis for understanding the multi-level factors that influence implementation outcomes and are used to guide implementation processes. This study aimed to identify and analyse TMFs that have an equity focus or have been used to implement interventions in populations who experience ethnicity or 'race'-related health inequities. METHODS: A scoping review was conducted to identify the relevant literature published from January 2011 to April 2022 by searching electronic databases (MEDLINE and CINAHL), the Dissemination and Implementation model database, hand-searching key journals and searching the reference lists and citations of studies that met the inclusion criteria. Titles, abstracts and full-text articles were screened independently by at least two researchers. Data were extracted from studies meeting the inclusion criteria, including the study characteristics, TMF description and operationalisation. TMFs were categorised as determinant frameworks, classic theories, implementation theories, process models and evaluation frameworks according to their overarching aim and described with respect to how equity and system-level factors influencing implementation were incorporated. RESULTS: Database searches yielded 610 results, 70 of which were eligible for full-text review, and 18 met the inclusion criteria. A further eight publications were identified from additional sources. In total, 26 papers describing 15 TMFs and their operationalisation were included. Categorisation resulted in four determinant frameworks, one implementation theory, six process models and three evaluation frameworks. One framework included elements of determinant, process and evaluation TMFs and was therefore classified as a 'hybrid' framework. TMFs varied in their equity and systems focus. Twelve TMFs had an equity focus and three were established TMFs applied in an equity context. All TMFs at least partially considered systems-level factors, with five fully considering macro-, meso- and micro-level influences on equity and implementation. CONCLUSIONS: This scoping review identifies and summarises the implementation science TMFs available to support equity-focused implementation. This review may be used as a resource to guide TMF selection and illustrate how TMFs have been utilised in equity-focused implementation activities.

Transdisciplinary stakeholder understandings of antimicrobial resistance: An integrative approach in Aotearoa New Zealand.

OBJECTIVE: Antimicrobial resistance (AMR) is a complex public health issue, with a range of influences across human, animal, and environmental health. Given the complexity of the problem, the diversity of stakeholders, and the failure of current policies to curb AMR worldwide, integrative approaches are needed to identify effective actions. Underpinned by systems thinking and One Health principles, this qualitative study explored how diverse AMR experts in Aotearoa New Zealand perceive the main drivers and effects of AMR. METHODS: Semi-structured interviews with clinical, academic, policy, community, and industry representatives were designed to elicit mental models of the causes and outcomes of AMR across dimensions. RESULTS: Thematic analysis revealed contrasting understandings of AMR causes across four domains: food-producing animals (livestock), healthcare, community, and environment. AMR was often framed as a problem of individual behaviour, despite many implicit references to underlying structural economic influences. The politics of collaboration was a further major underlying theme. The interviews highlighted fundamental connections between AMR and other complex issues, including poverty and environmental pollution. IMPLICATIONS FOR PUBLIC HEALTH: This study brings together the understandings of AMR of transdisciplinary stakeholders, providing some immediate insights for policy makers and setting the foundation for developing a collaborative system model of AMR as a basis for decision-making.

Effectiveness of population-wide screening and mass drug administration for leprosy control in Kiribati: the COMBINE protocol.

INTRODUCTION: Progress towards leprosy elimination is threatened by increasing incidence in 'hot-spot' areas where more effective control strategies are urgently required. In these areas, active case finding and leprosy prevention limited to known contacts is insufficient for control. Population-wide active case-finding together with universal prevention through mass drug administration (MDA) has been shown to be effective in 'hot-spot' areas, but is logistically challenging and expensive. Combining leprosy screening and MDA with other population-wide screening activities such as for tuberculosis may increase programme efficiency. There has been limited evaluation of the feasibility and effectiveness of combined screening and MDA interventions. The COMBINE study aims to bridge this knowledge gap. METHODS AND ANALYSIS: This implementation study will assess the feasibility and effectiveness of active leprosy case-finding and treatment, combined with MDA using either single-dose rifampicin or rifamycin-containing tuberculosis preventive or curative treatment, for reducing leprosy incidence in Kiribati. The leprosy programme will run over 2022-2025 in concert with population-wide tuberculosis screening-and-treatment in South Tarawa. The primary research question is to what extent the intervention reduces the annual leprosy new case detection rate (NCDR) in adults and children compared with routine screening and postexposure prophylaxis (PEP) among close contacts (baseline leprosy control activities). Comparisons will be made with (1) the preintervention NCDR separably among adults and children in South Tarawa (before-after study) and (2) the corresponding NCDRs in the rest of the country. Additionally, the postintervention prevalence of leprosy obtained from a survey of a 'hot-spot' sub-population will be compared with prevalence documented during the intervention. The intervention will be implemented in collaboration with the Kiribati National Leprosy Programme. ETHICS AND DISSEMINATION: Approval has been obtained from the Kiribati Ministry of Health and Medical Services (MHMS), the University of Otago (H22/111) and the University of Sydney (2021/127) Human Research Ethics Committees. Findings will be shared with the MHMS, local communities and internationally through publication.

Supporting implementation of interventions to address ethnicity-related health inequities: frameworks, facilitators and barriers - a scoping review protocol.

INTRODUCTION: Health inequities are differences in health between groups of people that are avoidable, unfair and unjust. Achieving equitable health outcomes requires approaches that recognise and account for the differences in levels of advantage between groups. Implementation science, which studies how to translate evidence-based interventions into routine practice, is increasingly recognised as an approach to address health inequities by identifying factors and processes that enable equitable implementation of interventions. This article describes the protocol for a scoping review of the literature relating to the equitable implementation of interventions, focusing on ethnicity-related health inequities. The scoping review aims to identify equity-focused implementation science theories, models and frameworks (TMFs) and to synthesise and analyse the evidence relating to the factors that aid or inhibit equitable implementation of health interventions. METHODS AND ANALYSIS: The scoping review is guided by the methodology developed by Arksey and O'Malley and enhanced by Levac and colleagues. Relevant literature will be identified by searching electronic databases, grey literature, hand-searching key journals and searching the reference lists and citations of studies that meet the inclusion criteria. We will focus on literature published from 2011 to the present. Titles, abstracts and full-text articles will be screened independently by two researchers; any disagreements will be resolved through discussion with another researcher. Extracted data will be summarised and analysed to address the scoping review aims. ETHICS AND DISSEMINATION: The scoping review will map the available literature on equity-focused implementation science TMFs and the facilitators and barriers to equitable implementation of interventions. Ethical approval is not required. Dissemination of the results of the review will include publications in peer-review journals and conference and stakeholder presentations. Findings from the review will support those implementing interventions to ensure that the implementation pathway and processes are equitable, thereby improving health outcomes and reducing existing inequities.

Late presentation of HIV infection among adults in New Zealand from 2011 to 2020.

OBJECTIVES: Early diagnosis of HIV is essential for successful treatment and controlling HIV spread in a population. We examined the frequency and characteristics of adults diagnosed late with HIV in New Zealand from 2011-2020. METHODS: Routine surveillance data were analysed. Those previously diagnosed overseas or as part of immigration screening, or with missing CD4 count were excluded. 'Late presentation' was defined as a CD4 count <350 cells/µL or an AIDS-defining event. 'Advanced HIV disease' were those with a CD4 count <200 cells/µL or an AIDS-defining event. Relative risks were calculated using Poisson regression. RESULTS: Of 1145 people, 40.5% presented late; 24.9% had advanced HIV disease. Of the 464 late diagnoses, 65.5% occurred among men-who-have-sex-with-men (MSM), 26.1% among heterosexuals, 8.4% among others. Heterosexual men and women were more likely to present late (55.3%) compared to MSM (35.6%). Amongst MSM, those who were older, of an ethnicity other than European, acquired HIV overseas, tested because symptomatic, or had their last negative test >2 years prior were more likely to present late and have advanced disease. Amongst heterosexuals, older age, tested because symptomatic, and Pacific ethnicity were associated with late presentation, and Maori, Pacific and Asian people were more likely to have advanced disease. CONCLUSIONS: There continues to be a high proportion of people diagnosed late with HIV. Identifying barriers for testing, missed opportunities for screenings and other factors that delay HIV diagnosis could help develop effective strategies to reduce this burden of late presentation - particularly among heterosexual individuals, non-Europeans, and older people.

Quality of life in people living with HIV in Aotearoa New Zealand: an exploratory cross-sectional study.

Quality of life (QoL) in people living with HIV (PLHIV) is reportedly worse than in people without HIV, with many factors impacting on this. We aimed to investigate QoL in PLHIV in New Zealand (NZ). In-person interviews were conducted including socio-demographic, health, social connectedness, and stigma-related questions. QoL was measured using the 13-question PozQoL Scale - summed to give a score between 13 and 65. Univariate linear regression was used to investigate factors associated with differences in PozQoL scores. PLHIV (n = 188) of different ethnicities from throughout NZ participated. The mean age was 47 years; 65% were men; 61% were men who have sex with men; 61% had been living with HIV for ≥10 years. The mean summary PozQoL score was 47.16. Factors associated with a lower mean PozQol included no sex in the last 12 months (-9.03), inability to meet basic needs (-7.47), ever (-6.49) or recently (-5.03), experiencing stigma or discrimination, mental health condition (-5.74), HIV diagnosis <5 years (-5.48), poor health (-5.43), being unemployed (-5.02), not having support (-4.71), and greater internalised stigma (-2.81). Improving QoL will require investment in peer support and community welfare programmes to better support PLHIV, and stigma reduction campaigns targeting the broader community.

Sensitivity of Reverse Transcription Polymerase Chain Reaction Tests for Severe Acute Respiratory Syndrome Coronavirus 2 Through Time.

BACKGROUND: Reverse transcription polymerase chain reaction (RT-PCR) tests are the gold standard for detecting recent infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Reverse transcription PCR sensitivity varies over the course of an individual's infection, related to changes in viral load. Differences in testing methods, and individual-level variables such as age, may also affect sensitivity. METHODS: Using data from New Zealand, we estimate the time-varying sensitivity of SARS-CoV-2 RT-PCR under varying temporal, biological, and demographic factors. RESULTS: Sensitivity peaks 4-5 days postinfection at 92.7% (91.4%-94.0%) and remains over 88% between 5 and 14 days postinfection. After the peak, sensitivity declined more rapidly in vaccinated cases compared with unvaccinated, females compared with males, those aged under 40 compared with over 40s, and Pacific peoples compared with other ethnicities. CONCLUSIONS: Reverse transcription PCR remains a sensitive technique and has been an effective tool in New Zealand's border and postborder measures to control coronavirus disease 2019. Our results inform model parameters and decisions concerning routine testing frequency.

Population rates of HIV, gonorrhoea and syphilis diagnoses by sexual orientation in New Zealand.

INTRODUCTION: Globally, gay and bisexual men (GBM) are over-represented in HIV, syphilis and gonorrhoea cases. However, surveillance systems rarely provide meaningful measures of inequity, such as population-specific rates, due to a lack of sexual orientation denominators. HIV, gonorrhoea and syphilis are legally notifiable diseases in New Zealand (NZ); we calculate rates by sexual orientation for the first time. METHODS: We analysed 2019 national surveillance data on HIV, syphilis and gonorrhoea notifications disaggregated by sexual orientation. Unique health records identified duplicate notifications and reinfections. Missing data were imputed from known cases. We used the NZ Health Survey 2014/2015 to estimate population sizes by sexual orientation, measured in two ways (current sexual identity, sexual contact in the previous 12 months with men, women or both). We calculated notification rates per 100 000 for each sexual orientation subgroup and rate ratios. RESULTS: In 2019, GBM accounted for 76.3%, 65.7% and 39.4% of HIV, syphilis and gonorrhoea notifications, respectively. Population rates per 100 000 for HIV were 158.3 (gay/bisexual men) and 0.5 (heterosexuals); for syphilis, population rates per 100 000 were 1231.1 (gay/bisexual men), 5.0 (lesbian/bisexual women) and 7.6 (heterosexuals); for gonorrhoea (imputed), population rates per 100 000 were 6843.2 (gay/bisexual men), 225.1 (lesbian/bisexual women) and 120.9 (heterosexuals). The rate ratios for GBM compared with heterosexuals were: 348.3 (HIV); 162.7 (syphilis); and 56.6 (gonorrhoea). Inequities remained in sensitivity analysis (substituting sexual identity with sexual behaviour in the previous 12 months). CONCLUSION: GBM in NZ experience profound inequities in HIV, syphilis and gonorrhoea. Rate ratios by sexual orientation provide useful 'at-a-glance' measures of inequity in disease incidence.

HIV in women in Aotearoa New Zealand: 25 years of surveillance data.

AIM: We describe the characteristics of women diagnosed with HIV and AIDS in Aotearoa New Zealand over the last 25 years, and of women living with HIV in New Zealand in order to guide the response for HIV prevention and care. METHODS: Data on women diagnosed with HIV and AIDS in New Zealand (1996-2020) were collected through routine surveillance case reports from healthcare providers. CD4 cell count <350 cells/mm³ was considered a late diagnosis. Women living with HIV by 31 December 2020 included those first diagnosed in New Zealand and those previously diagnosed overseas. RESULTS: A total of 634 women have been diagnosed with HIV (18% of all diagnoses in this time): most cases were acquired through heterosexual contact (82%). Twenty-eight percent (n=180/634) acquired HIV in New Zealand, of whom 43% were diagnosed late. AIDS was diagnosed in 128 women (72% within three months of HIV diagnosis). An estimated 570 women (77% aged >40 years) were living with diagnosed HIV at the end of 2020. CONCLUSION: The number of women diagnosed with HIV each year in New Zealand has remained steady over recent years. More timely testing and diagnosis is essential to ensure women with HIV have access to appropriate treatment and support.

Creating symptom-based criteria for diagnostic testing: a case study based on a multivariate analysis of data collected during the first wave of the COVID-19 pandemic in New Zealand.

BACKGROUND: Diagnostic testing using PCR is a fundamental component of COVID-19 pandemic control. Criteria for determining who should be tested by PCR vary between countries, and ultimately depend on resource constraints and public health objectives. Decisions are often based on sets of symptoms in individuals presenting to health services, as well as demographic variables, such as age, and travel history. The objective of this study was to determine the sensitivity and specificity of sets of symptoms used for triaging individuals for confirmatory testing, with the aim of optimising public health decision making under different scenarios. METHODS: Data from the first wave of COVID-19 in New Zealand were analysed; comprising 1153 PCR-confirmed and 4750 symptomatic PCR negative individuals. Data were analysed using Multiple Correspondence Analysis (MCA), automated search algorithms, Bayesian Latent Class Analysis, Decision Tree Analysis and Random Forest (RF) machine learning. RESULTS: Clinical criteria used to guide who should be tested by PCR were based on a set of mostly respiratory symptoms: a new or worsening cough, sore throat, shortness of breath, coryza, anosmia, with or without fever. This set has relatively high sensitivity (> 90%) but low specificity (< 10%), using PCR as a quasi-gold standard. In contrast, a group of mostly non-respiratory symptoms, including weakness, muscle pain, joint pain, headache, anosmia and ageusia, explained more variance in the MCA and were associated with higher specificity, at the cost of reduced sensitivity. Using RF models, the incorporation of 15 common symptoms, age, sex and prioritised ethnicity provided algorithms that were both sensitive and specific (> 85% for both) for predicting PCR outcomes. CONCLUSIONS:  If predominantly respiratory symptoms are used for test-triaging,  a large proportion of the individuals being tested may not have COVID-19. This could overwhelm testing capacity and hinder attempts to trace and eliminate infection. Specificity can be increased using alternative rules based on sets of symptoms informed by multivariate analysis and automated search algorithms, albeit at the cost of sensitivity. Both sensitivity and specificity can be improved through machine learning algorithms, incorporating symptom and demographic data, and hence may provide an alternative approach to test-triaging that can be optimised according to prevailing conditions.

Whole-genome sequencing and ad hoc shared genome analysis of Staphylococcus aureus isolates from a New Zealand primary school.

Epidemiological studies of communicable diseases increasingly use large whole-genome sequencing (WGS) datasets to explore the transmission of pathogens. It is important to obtain an initial overview of datasets and identify closely related isolates, but this can be challenging with large numbers of isolates and imperfect sequencing. We used an ad hoc whole-genome multi locus sequence typing method to summarise data from a longitudinal study of Staphylococcus aureus in a primary school in New Zealand. Each pair of isolates was compared and the number of genes where alleles differed between isolates was tallied to produce a matrix of "allelic differences". We plotted histograms of the number of allelic differences between isolates for: all isolate pairs; pairs of isolates from different individuals; and pairs of isolates from the same individual. 340 sequenced isolates were included, and the ad hoc shared genome contained 445 genes. There were between 0 and 420 allelic differences between isolate pairs and the majority of pairs had more than 260 allelic differences. We found many genetically closely related S. aureus isolates from single individuals and a smaller number of closely-related isolates from separate individuals. Multiple S. aureus isolates from the same individual were usually very closely related or identical over the ad hoc shared genome. Siblings carried genetically similar, but not identical isolates. An ad hoc shared genome approach to WGS analysis can accommodate imperfect sequencing of the included isolates, and can provide insights into relationships between isolates in epidemiological studies with large WGS datasets containing diverse isolates.

Risk Factors for Hepatitis B Virus Transmission in Oman.

OBJECTIVES: Hepatitis B virus (HBV) is a major public health problem worldwide. The prevalence of HBV is dependent on the modes of transmission. Chronic hepatitis B (CHB) infection can progress to liver cirrhosis and hepatocellular carcinoma. Oman is regarded as an intermediate endemic region and has had a neonatal vaccine against HBV since 1990. However, little research has been conducted regarding risk factors for HBV transmission. Our study aimed to identify the prevalence of major risk factors for acquiring HBV in Oman. METHODS: We conducted a retrospective chart review of all adult Omani patients diagnosed with CHB at two tertiary hospitals in Oman, Sultan Qaboos University Hospital and Armed Forces Hospital, between February 2009 and July 2013. The prevalence of major risk factors was identified by interviewing CHB patients using a standard questionnaire during their follow-up visits to the hepatology clinic at both hospitals. The risk factor frequency was stratified by age, gender, and educational level. RESULTS: A total of 274 patients were interviewed; 52.2% of the participants were males. The median age for men was 35.9 years and 35.1 years for women, with 75.5% aged 20-39 years old. The antenatal screening was the most common means of identifying HBV infection in females, and pre-blood donation screening was the most common in males. Intra-familial contact with HBV infected persons and behavioral risks such as body piercing (females) and barber shaving (males) were more common than nosocomial risk factors. Knowledge about HBV infection was scarce among our participants. More than half of the participants had a positive family history of HBV infection. There was a significant association between HBV infection and age groups, and educational levels (p < 0.050 and p < 0.001, respectively). Among those who were infected due to intra-familial contact or behavioral risk, there was a significant difference between the two sexes (p < 0.020) and between the three age groups (< 23, 23-28, >28) of HBV positive mothers (33.3%, 14.3%, and 6.6%, respectively; p < 0.050). There was also a statistically significant difference among different educational levels (p < 0.050). CONCLUSIONS: Direct contact of infected individuals within a family and exposure to high-risk behaviors such as piercing and barber shaving are the main reported risk factors for HBV infection in Omani patients. Reducing the vertical and horizontal transmission of HBV in Oman could be improved by implementing routine antenatal screening of pregnant women and a greater focus on contact screening, respectively.

"We have been warned"-preparing now to prevent the next pandemic.

'COVID-19: Make it the Last Pandemic' is the aspirational title of the recently released report by the Independent Panel for Pandemic Preparedness and Response. This panel, co-chaired by Helen Clark and Ellen Johnson Sirleaf, was convened in mid-2020 by the World Health Organization (WHO) to assess the global handling of COVID-19.

COVID-19 in New Zealand and the impact of the national response: a descriptive epidemiological study.

BACKGROUND: In early 2020, during the COVID-19 pandemic, New Zealand implemented graduated, risk-informed national COVID-19 suppression measures aimed at disease elimination. We investigated their impacts on the epidemiology of the first wave of COVID-19 in the country and response performance measures. METHODS: We did a descriptive epidemiological study of all laboratory-confirmed and probable cases of COVID-19 and all patients tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in New Zealand from Feb 2 to May 13, 2020, after which time community transmission ceased. We extracted data from the national notifiable diseases database and the national SARS-CoV-2 test results repository. Demographic features and disease outcomes, transmission patterns (source of infection, outbreaks, household transmission), time-to-event intervals, and testing coverage were described over five phases of the response, capturing different levels of non-pharmaceutical interventions. Risk factors for severe outcomes (hospitalisation or death) were examined with multivariable logistic regression and time-to-event intervals were analysed by fitting parametric distributions using maximum likelihood estimation. FINDINGS: 1503 cases were detected over the study period, including 95 (6·3%) hospital admissions and 22 (1·5%) COVID-19 deaths. The estimated case infection rate per million people per day peaked at 8·5 (95% CI 7·6-9·4) during the 10-day period of rapid response escalation, declining to 3·2 (2·8-3·7) in the start of lockdown and progressively thereafter. 1034 (69%) cases were imported or import related, tending to be younger adults, of European ethnicity, and of higher socioeconomic status. 702 (47%) cases were linked to 34 outbreaks. Severe outcomes were associated with locally acquired infection (crude odds ratio [OR] 2·32 [95% CI 1·40-3·82] compared with imported), older age (adjusted OR ranging from 2·72 [1·40-5·30] for 50-64 year olds to 8·25 [2·59-26·31] for people aged ≥80 years compared with 20-34 year olds), aged residential care residency (adjusted OR 3·86 [1·59-9·35]), and Pacific peoples (adjusted OR 2·76 [1·14-6·68]) and Asian (2·15 [1·10-4·20]) ethnicities relative to European or other. Times from illness onset to notification and isolation progressively decreased and testing increased over the study period, with few disparities and increasing coverage of females, Maori, Pacific peoples, and lower socioeconomic groups. INTERPRETATION: New Zealand's response resulted in low relative burden of disease, low levels of population disease disparities, and the initial achievement of COVID-19 elimination. FUNDING: Ministry of Business Innovation and Employment Strategic Scientific Investment Fund, and Ministry of Health, New Zealand.

One Health Aotearoa: a transdisciplinary initiative to improve human, animal and environmental health in New Zealand.

There is increased recognition that complex health challenges at the human-animal-environmental interface require a transdisciplinary, "whole-of-society" approach. This philosophy is particularly pertinent in Aotearoa-New Zealand because of the country's relatively isolated island ecosystem, economic reliance on agriculture and its intensification, and existing indigenous worldview that emphasises holism and interconnectivity between humans, animals and the environment. In New Zealand, the One Health Aotearoa (OHA) alliance was established in order to better connect researchers and to address a growing number of infectious diseases challenges. The emphasis of OHA is to bring together and facilitate interactions between people from diverse disciplines, link to stakeholders and communities, and engage with policy-makers, government operational agencies, and funders, thus providing a holistic and integrative systems-thinking approach to address priority questions and achieve desired outcomes in One Health. The initial focus of OHA has been on infectious diseases, but there is increasing recognition of the potential benefits of the alliance to address broader complex issues. Greater involvement and overlap of the environmental sciences, human and animal health sciences, social science, and indigenous kaupapa Maori research is particularly critical for ensuring its success within the New Zealand context. Given the economic and cultural importance of New Zealand's "clean, green" image, a One Health approach that draws strongly on the environmental sciences makes particular sense. Furthermore, as the global environment becomes increasingly stressed by anthropogenic pressures our research may hold potential solutions for similar challenges elsewhere.

Surveillance of Leprosy in Kiribati, 1935-2017.

In Kiribati, unlike most countries, high and increasing numbers of cases of leprosy have been reported despite the availability of multidrug therapy and efforts to improve case finding and management. Historic records show that 28 cases had been identified by 1925. A systematic population survey in 1997 identified 135 new cases; the mean incidence rate for 1993-1997 was 7.4/10,000 population. After administering mass chemoprophylaxis, the country reached the elimination threshold (prevalence <1/10,000), but case numbers have rebounded. The mean annualized rate of new cases in 2013-2017 was 15/10,000 population, with the highest new case rates (>20/10,000 population) in the main population centers of South Tarawa and Betio. Spread is expected to continue in areas where crowding and poor socioeconomic conditions persist and may accelerate as sea levels rise from climate change. New initiatives to improve social conditions are needed, and efforts such as postexposure chemoprophylaxis should be implemented to prevent spread.

Predicting the impact of household contact and mass chemoprophylaxis on future new leprosy cases in South Tarawa, Kiribati: A modelling study.

BACKGROUND: The country of Kiribati is a small Pacific island nation which had a new case detection rate of 191 per 100,000 in 2016, and is one of the few countries yet to reach the WHO leprosy elimination goal. Chemoprophylaxis of household contacts of new cases, or to the whole population in a highly endemic areas have been found to be effective in reducing new case rates. This study investigated the potential impact of different chemoprophylaxis strategies on future cases in South Tarawa, the main population centre of Kiribati. METHODOLOGY: The microsimulation model SIMCOLEP was calibrated to simulate the South Tarawa population and past leprosy control activities, and replicate annual new cases from 1989 to 2016. The impact of six different strategies for delivering one round of single dose rifampicin (SDR) chemoprophylaxis to household contacts of new cases and/or one or three rounds of SDR to the whole population was modelled from 2017 to 2030. PRINCIPAL FINDINGS: Our model predicted that continuing the existing control program of high levels of public awareness, passive case detection, and treatment with multidrug treatment would lead to a substantial reduction in cases but this was less effective than all modelled intervention scenarios. Mass chemoprophylaxis led to a faster initial decline in cases than household contact chemoprophylaxis alone, however the decline under the latter was sustained for longer. The greatest cumulative impact was for household contact chemoprophylaxis with three rounds of mass chemoprophylaxis at one-year intervals. CONCLUSIONS: The results suggest that control of leprosy would be achieved most rapidly with a combination of intensive population-based and household chemoprophylaxis. These findings may be generalisable to other countries where crowding places social contacts as well as household contacts of cases at risk of developing leprosy.