Increased Incidence of Legionellosis after Improved Diagnostic Methods, New Zealand, 2000-2020.

Legionellosis, notably Legionnaires' disease, is recognized globally and in New Zealand (Aotearoa) as a major cause of community-acquired pneumonia. We analyzed the temporal, geographic, and demographic epidemiology and microbiology of Legionnaires' disease in New Zealand by using notification and laboratory-based surveillance data for 2000‒2020. We used Poisson regression models to estimate incidence rate ratios and 95% CIs to compare demographic and organism trends over 2 time periods (2000-2009 and 2010-2020).

Retrofitting home insulation reduces incidence and severity of chronic respiratory disease.

To assess whether retrofitting home insulation can reduce the risk of respiratory disease incidence and exacerbation, a retrospective cohort study was undertaken using linked data from a national intervention program. The study population was made up of 1 004 795 residents from 205 001 New Zealand houses that received an insulation subsidy though a national Energy Efficiency and Conservation Authority program. A difference-in-difference model compared changes in the number of prescriptions dispensed for respiratory illness post- insulation to a control population over the same timeframe.

How has contraceptive provision at Family Planning clinics in Aotearoa New Zealand changed between 2009, 2014 and 2019: a cross-sectional analysis.

Aim: To investigate changes in contraceptive starts among Family Planning clients in 2009, 2014 and 2019.

Methods: National data of 75,825 contraceptive starts of clients at Family Planning clinics in New Zealand in 2009, 2014 and 2019 were analysed to measure changes in contraceptive starts across the three points in time. Data were analysed by age and ethnicity at each point in time, and by deprivation in 2019.

An empirical test of the biodiversity hypothesis: Exposure to plant diversity is associated with a reduced risk of childhood acute lymphoblastic leukemia.

The biodiversity hypothesis posits that declining biodiversity may be responsible, at least in part, for the global increase in immune diseases. However, few studies have been able to demonstrate a link between exposure to biodiversity and specific health outcomes. We test whether exposure to plant diversity protects against childhood acute lymphoblastic leukemia (ALL) by promoting immune maturation.

Association between home insulation and hospital admission rates: retrospective cohort study using linked data from a national intervention programme.

Objectives: To investigate whether retrofitting insulation into homes can reduce cold associated hospital admission rates among residents and to identify whether the effect varies between different groups within the population and by type of insulation.

Design: A quasi-experimental retrospective cohort study using linked datasets to evaluate a national intervention programme.

Participants: 994 317 residents of 204 405 houses who received an insulation subsidy through the Energy Efficiency and Conservation Authority Warm-up New Zealand: Heat Smart retrofit programme between July 2009 and June 2014.

Evaluating a community-based public health intervention using a complex systems approach.

Background: This article outlines the methods being used to evaluate a community-based public health intervention. This evaluation approach recognizes that not only is the intervention, Healthy Families NZ, complex, but the social systems within which it is being implemented are complex.

Methods: To address challenges related to complexity, we discuss three developing areas within evaluation theory and apply them to an evaluation case example.

A cost effectiveness analysis of community water fluoridation in New Zealand.

Aim: The aim of the study was to use recent data to determine whether Community Water Fluoridation (CWF) remains a cost effective public health intervention in New Zealand, given a reduction in dental caries in all communities over time.

Method: Local authorities that fluoridated their water supplies were asked to complete a questionnaire regarding fixed and variable costs incurred from CWF. Cost savings were calculated using data from the 2009 New Zealand Oral Health Survey.