COVID-19-related hospitalizations among Aotearoa, New Zealand children during the Omicron era of SARS-CoV-2.

Objectives: This multicenter cohort study describes Aotearoa New Zealand children hospitalized during the country's first wave of sustained SARS-CoV-2 transmission, Omicron variant. Methods: Children younger than 16 years, hospitalized for >6 hours with COVID-19 across New Zealand from January to May 2022 were included. Admissions for all Maori and Pacific and every second non-Maori non-Pacific children were selected to support equal explanatory power for ethnic grouping. Attribution of hospital admission, demography, clinical presentation, comorbidity, treatment, and outcome data were collected. Results: Of 444 hospitalizations of children positive for COVID-19, 292 (65.5%) from 290 children were considered admissions attributable to COVID-19. Of these admissions, 126 (43.4%) were aged under 1; 118 (40.7%), 99 (34.1%), and 87 (30.0%) were children of Maori, Pacific, and non-Maori non-Pacific ethnicity, respectively. Underlying respiratory disease was the most common comorbidity, present in 22 children (7.6%); 16 children (5.5%) were immunosuppressed. Median length of stay was 1 day (interquartile range 0.0-2.0). Four children received antiviral, 69 (24%) antibacterial, and 24 (8%) supplemental oxygen. Although eight children required intensive care, there were no deaths. Conclusions: Children hospitalized during the first significant wave of SARS-CoV-2 infection in New Zealand presented with a multi-system viral illness and rarely with severe disease.

Improved paediatric antimicrobial prescribing with a smartphone application: a before and after interventional study.

INTRODUCTION: Children have a high consumption of antimicrobials that require complicated decision-making by prescribers. Despite this, antimicrobial stewardship (AMS) interventions are often not translated into paediatric medicine. Script is a smartphone application (app) launched in Auckland, New Zealand to support decision-making for antimicrobial prescribers. The aim was to improve adherence to existing local clinical guidelines for both adult and paediatric infections. METHODS: Inpatient and emergency department antimicrobial prescriptions were prospectively collected and evaluated for guideline adherence. Baseline prescribing data were collected and compared with prescribing at 4 months and 1 year after the app was launched. Prescriptions were graded as 'appropriate' or 'inappropriate' by investigators. Grading was done blinded to timing of the prescription relative to the intervention. RESULTS: Following the launch of the Script app, guideline adherence significantly increased from 241 of 348 (69%) antimicrobial prescriptions graded as appropriate during the baseline period to 301 of 359 (83%) after 4 months (p<0.0001). This improvement from baseline was sustained at 1 year with 263 of 323 (81%) adherence (p<0.001). At 1 year, this improvement could be demonstrated separately for medical, surgical and emergency department prescriptions. CONCLUSION: There was a significant and sustained improvement in adherence to paediatric antimicrobial guidelines following the introduction of a prescribing support app. The need to seek guidance for antimicrobial doses due to the age-based and weight-based calculations in paediatrics may mean that AMS interventions such as decision support and prescribing tools are particularly well suited to paediatric prescribing.

Long-Term Impact of a Smartphone App on Prescriber Adherence to Antibiotic Guidelines for Adult Patients With Community-Acquired Pneumonia: Interrupted Time-Series Study.

BACKGROUND: Mobile health platforms like smartphone apps that provide clinical guidelines are ubiquitous, yet their long-term impact on guideline adherence remains unclear. In 2016, an antibiotic guidelines app, called SCRIPT, was introduced in Auckland City Hospital, New Zealand, to provide local antibiotic guidelines to clinicians on their smartphones. OBJECTIVE: We aimed to assess whether the provision of antibiotic guidelines in a smartphone app resulted in sustained changes in antibiotic guideline adherence by prescribers. METHODS: We analyzed antibiotic guideline adherence rates during the first 24 hours of hospital admission in adults diagnosed with community-acquired pneumonia using an interrupted time-series study with 3 distinct periods post app implementation (ie, 3, 12, and 24 months). RESULTS: Adherence increased from 23% (46/200) at baseline to 31% (73/237) at 3 months and 34% (69/200) at 12 months, reducing to 31% (62/200) at 24 months post app implementation (P=.07 vs baseline). However, increased adherence was sustained in patients with pulmonary consolidation on x-ray (9/63, 14% at baseline; 23/77, 30% after 3 months; 32/92, 35% after 12 month; and 32/102, 31% after 24 months; P=.04 vs baseline). CONCLUSIONS: An antibiotic guidelines app increased overall adherence, but this was not sustained. In patients with pulmonary consolidation, the increased adherence was sustained.

Using Heart Rate Variability Methods for Health-Related Outcomes in Outdoor Contexts: A Scoping Review of Empirical Studies.

Heart rate variability (HRV) is a psychophysiological variable that is often used in applied analysis techniques to indicate health status because it provides a window into the intrinsic regulation of the autonomic nervous system. However, HRV data analysis methods are varied and complex, which has led to different approaches to data collection, analysis, and interpretation of results. Our scoping review aimed to explore the diverse use of HRV methods in studies designed to assess health outcomes in outdoor free-living contexts. Four database indexes were searched, which resulted in the identification of 17,505 candidate studies. There were 34 studies and eight systematic reviews that met the inclusion criteria. Just over half of the papers referenced the 1996 task force paper that outlined the standards of measurement and physiological interpretation of HRV data, with even fewer adhering to recommended HRV recording and analysis procedures. Most authors reported an increase in parasympathetic (n = 23) and a decrease in systematic nervous system activity (n = 20). Few studies mentioned methods-related limitations and challenges, despite a wide diversity of recording devices and analysis software used. We conclude our review with five recommendations for future research using HRV methods in outdoor and health-related contexts.

Validating the Remote First Aid Self-Efficacy Scale for Use in Evaluation and Training of First Responders in Remote Contexts.

INTRODUCTION: The purpose of this study was to investigate the psychometric properties of the remote first aid self-efficacy scale (RFA SES). The RFA SES is a 30-item self-report scale developed in response to emerging evidence showing that self-efficacy is predictive of performance. METHODS: Trained alumni from Wilderness Medical Associates (WMA) training courses and less trained students from Laurentian University (LU) were recruited via email to complete an online questionnaire at 2 different periods (T1 and T2). The questionnaire included demographic questions, the 30-item RFA SES, the 10-item Connor-Davidson resilience scale (CD-RISC), and the 10-item generalized self-efficacy scale (GSES). Data analysis included assessment of the dimensionality, reliability, and validity of the scale. RESULTS: There were 448 alumni from WMA and 1106 students from LU who participated in the study. The RFA SES demonstrated a clear unidimensional structure. The mean interitem correlation was 0.75 at T1. Test-retest reliability (T1 to T2) was high for both the LU group (intraclass correlation [ICC]=0.90) and the WMA group (ICC=0.92). Moderate correlations were found between RFA SES and CD-RISC (r=0.42, P<0.001), a general measure of resilience, and the GSES (r=0.48, P<0.001), a general measure of self-efficacy. Wilderness Medical Associates participants showed higher mean scores than LU students at T1 (t [569]=16.2, P<0.001). CONCLUSIONS: The RFA SES is a unidimensional, reliable, and potentially valid scale. Further research should focus on item reduction followed by additional tests of reliability and validity.

The Impact of a Pharmacist-Led Intravenous to Oral Switch of Metronidazole: A Before-and-After Study.

(1) Background. Intravenous (IV) to oral switch (IVOS) of antibiotics can reduce the length of hospitalisation, risk of IV catheter complications, and hospital costs. Pharmacists can play an instrumental role in implementing an IVOS initiative. The aim of this study is to evaluate the impact of pharmacist-led IVOS of metronidazole. (2) Method. This was an observational study conducted in a New Zealand hospital. During a 3-month intervention period, pharmacists identified patients receiving IV metronidazole; then initiated an IVOS for patients who met the criteria. The comparator groups were patients who were not switched by pharmacists in the post-intervention (post-IVOS) group, or patients treated with either IV or oral metronidazole prior to the intervention (pre-IVOS). Primary outcome measures were switch rate and duration of IV metronidazole treatment. Secondary outcome measures were readmission and/or repeat surgery within 90 days of discharge and the length of hospital stay. (3) Results. In total, 203 patients were included: 100 in the pre-IVOS and 103 in the post-IVOS groups. Pharmacists switched 63/93 (67.7%) of eligible patients to oral metronidazole in the post-IVOS period. Only 9/89 (10.1%) of IVOS eligible patients were switched in the pre-IVOS group. In the post-IVOS group, the mean duration of IV metronidazole treatment in patients switched by pharmacists was shorter than in those who were not switched by pharmacists (2.5 ± 2.8 days vs. 4.8 ± 5.9 days, p = 0.012). No significant difference was found in readmission or repeat surgery within 90 days of discharge for patients switched by pharmacists versus patients who were not switched by pharmacists. (4) Conclusion. Our data have demonstrated successful implementation of the hospital-approved pharmacist-led IVOS service.

Clinical features of patients hospitalised with COVID-19 from February to October 2020, during the early waves of the pandemic in New Zealand.

AIM: As New Zealand transitions towards endemic SARS-CoV-2, understanding patient factors predicting severity, as well as hospital resourcing requirements will be essential for future planning. METHODS: We retrospectively enrolled patients hospitalised with COVID-19 from 26 February to 5 October 2020 as part of the COVID-19 HospitalisEd Patient SeverIty Observational Study NZ (COHESION). Data on demographics, clinical course and outcomes were collected and analysed as a descriptive case series. RESULTS: Eighty-four patients were identified across eight district health boards. Forty-one (49%) were male. The median age was 58 years [IQR: 41.7-70.3 years]. By ethnicity, hospitalisations included 38 NZ European (45%), 19 Pasifika (23%), 13 Maori (15%), 12 Asian (14%) and 2 Other (2%). Pre-existing co-morbidities included hypertension (26/82, 32%), obesity (16/66, 24%) and diabetes (18/81, 22%). The median length of stay was four days [IQR: 2-15 days]. Twelve patients (12/83, 14%) were admitted to an intensive care unit or high dependency unit (ICU/HDU). Ten (10/83, 12%) patients died in hospital of whom seven (70%) were not admitted to ICU/HDU; the median age at death was 83 years. CONCLUSION: Despite initially low case numbers in New Zealand during 2020, hospitalisation with COVID-19 was associated with a high mortality and hospital resource requirements.

Maori Experiences and Beliefs about Antibiotics and Antimicrobial Resistance for Acute Upper Respiratory Tract Symptoms: A Qualitative Study.

Antimicrobial resistance (AMR) is a threat to public health. Addressing unnecessary antibiotic use provides an opportunity to reduce antibiotic consumption and to slow AMR. Understanding people's beliefs is important for informing antimicrobial stewardship (AMS) initiatives. Within New Zealand, health inequities exist between Maori and non-Maori; however, no research has examined Maori beliefs about antibiotics and AMR. The aim of this study was to explore the experiences related to antibiotic use of Maori in New Zealand. In-depth, semi-structured interviews were conducted with 30 Maori adults recruited from primary care to explore the experiences, perceptions and beliefs that Maori have about antibiotics, and about AMR. Overall, 30 Maori adults (23% male; age range from 20 to 77 years) participated. Three themes emerged: systemic-, social-, and individual-related factors. From these themes, seven subthemes explained the factors that influenced antibiotic use and their perceptions of AMR in Maori: general practitioner (GP) times and ratios, effect of colonisation, lack of knowledge and information, access and poverty barriers, relationship with health professionals, illness perceptions, treatment beliefs and Whaakaro (thoughts), and beliefs pertaining to natural (rongoa) and Western medicine. Participants identified potential solutions to improve antibiotic use such as cultural support and involving Te Ao Maori; recognising these can inform future AMS initiatives.

An eight-plex immunoassay for Group A streptococcus serology and vaccine development.

Group A Streptococcus (GAS) is a major human pathogen responsible for superficial infections through to life-threatening invasive disease and the autoimmune sequelae acute rheumatic fever (ARF). Despite a significant global economic and health burden, there is no licensed vaccine available to prevent GAS disease. Several pre-clinical vaccines that target conserved GAS antigens are in development. Assays that measure antigen-specific antibodies are essential for vaccine research. The aim of this study was to develop a multiplex beadbased immunoassay that can detect and quantify antibody responses to multiple GAS antigen targets in small volume blood samples. This builds on our existing triplex assay comprised of antigens used in clinical serology for the diagnosis of ARF (SLO, DNase B and SpnA). Five additional conserved putative GAS vaccine antigens (Spy0843, SCPA, SpyCEP, SpyAD and the Group A carbohydrate), were coupled to spectrally unique beads to form an 8-plex antigen panel. After optimisation of the assay protocol, standard curves were generated, and assessments of assay specificity, precision and reproducibility were conducted. A broad range of antibody (IgG) titres were able to be quickly and accurately quantified from a single serum dilution. Assay utility was assessed using a panel of 62 clinical samples including serum from adults with GAS bacteraemia and children with ARF. Circulating IgG to all eight antigens was elevated in patients with GAS disease (n = 23) compared to age-matched controls (n = 39) (P < 0.05). The feasibility of using dried blood samples to quantify antigen-specific IgG was also demonstrated. In summary, a robust and reproducible 8-plex assay has been developed that simultaneously quantifies IgG antibodies to GAS vaccine and diagnostic antigens.

Emergency care with lay responders in underserved populations: a systematic review.

OBJECTIVE: To assess the individual and community health effects of task shifting for emergency care in low-resource settings and underserved populations worldwide. METHODS: We systematically searched 13 databases and additional grey literature for studies published between 1984 and 2019. Eligible studies involved emergency care training for laypeople in underserved or low-resource populations, and any quantitative assessment of effects on the health of individuals or communities. We conducted duplicate assessments of study eligibility, data abstraction and quality. We synthesized findings in narrative and tabular format. FINDINGS: Of 19 308 papers retrieved, 34 studies met the inclusion criteria from low- and middle-income countries (21 studies) and underserved populations in high-income countries (13 studies). Targeted emergency conditions included trauma, burns, cardiac arrest, opioid poisoning, malaria, paediatric communicable diseases and malnutrition. Trainees included the general public, non-health-care professionals, volunteers and close contacts of at-risk populations, all trained through in-class, peer and multimodal education and public awareness campaigns. Important clinical and policy outcomes included improvements in community capacity to manage emergencies (14 studies), patient outcomes (13 studies) and community health (seven studies). While substantial effects were observed for programmes to address paediatric malaria, trauma and opioid poisoning, most studies reported modest effect sizes and two reported null results. Most studies were of weak (24 studies) or moderate quality (nine studies). CONCLUSION: First aid education and task shifting to laypeople for emergency care may reduce patient morbidity and mortality and build community capacity to manage health emergencies for a variety of emergency conditions in underserved and low-resource settings.

The impacts of New Zealand's COVID-19 epidemic response on community antibiotic use and hospitalisation for pneumonia, peritonsillar abscess and rheumatic fever.

BACKGROUND: The rate of community antibiotic use in New Zealand (NZ) is high and some may be unnecessary. Non-pharmaceutical public health interventions (Alert Levels) were implemented in 2020 to reduce the spread of COVID-19 in NZ and were likely to have affected antibiotic prescribing. METHODS: We aimed to identify the impact of these public health interventions on community antibiotic dispensing. We also examined rates of hospitalisation with infectious diseases that could be influenced by changing community antibiotic use. A retrospective review of two national databases was undertaken. FINDINGS: 1.17 million people received 1.19 million prescriptions for antibiotics between 23/02/2020 and 18/07/2020. Antibiotic dispensing rates fell from 14 prescriptions per 1000 population per week during pre-Alert Level weeks to 9 prescriptions per 1000 population per week (a reduction of 36%) during the weeks of COVID Alert Level 3-4. Large reductions were seen with antibiotics predominantly used for respiratory- or urinary-tract infections. Hospital discharges with sentinel infections did not increase over this period; pneumonia discharges during Alert Level weeks were lower than in 2017-2019 (3 vs 6 discharges per 100,000 population). INTERPRETATION: A large reduction in community antibiotic dispensing was observed in NZ during the implementation of non-pharmaceutical public health interventions to eliminate COVID-19. Despite this marked reduction in antibiotic use, there was no increase in rates of hospitalisation for sentinel infections that community antibiotic use could prevent. These findings suggest that countries with high rates of antibiotic use could significantly reduce their use without an increase in morbidity. FUNDING: No financial support received.

Quality of work life of paramedics practicing community paramedicine in northern Ontario, Canada: a mixed-methods sequential explanatory study.

INTRODUCTION: This article aimed to evaluate pilot community paramedicine (CP) programs in northern Ontario from the perspectives of paramedics to gain program recommendations related to both rural and urban settings. METHODS: An online questionnaire was created and distributed to 879 paramedics with and without CP experience employed at eight emergency medical services providers in northern Ontario. An explanatory sequential design was used to analyze and synthesize the results from the quantitative survey items and the open-ended responses. RESULTS: Seventy-five (40.5%) respondents participated in a CP program, and the majority of 75 paramedics who indicated they participated in CP (n=41, 54.4%) were from rural areas. CP was generally well received by both paramedics currently practicing CP and those who were not practicing CP. The majority (86.3%) of paramedics stated paramedics should be practicing CP in the future. Paramedics identified developing professional relationships and improving health promotion as positive aspects of CP. Areas for CP program improvement included better organization and scheduling, improved training and a need for better patient tracking software. CONCLUSION: Engaging and consulting paramedics in the ongoing process of CP development and implementation is important to ensure they feel valued and are part of the change process.

Reducing Expectations for Antibiotics in Patients With Upper Respiratory Tract Infections: A Primary Care Randomized Controlled Trial.

PURPOSE: Many family practitioners prescribe antibiotics for patients with upper respiratory tract infections (URTIs) to meet patients' expectations. We evaluated the impact of providing brief tablet-based information about antibiotic treatment of URTIs on patients' expectations for antibiotics and on family practitioners' antibiotic-prescribing behavior. METHODS: We performed a 3-arm randomized controlled trial among patients presenting with URTIs at 2 urban family practices in Auckland, New Zealand, during winter 2018. Participants were randomly allocated to view a presentation about the futility of antibiotic treatment of URTIs, the adverse effects associated with antibiotics, or the benefits of healthy diet and exercise (active control), immediately before their consultation. Before and after viewing the presentations, participants used a Likert scale to rate the strength of their belief that antibiotics are effective for treating URTIs and of their desire to be prescribed an antibiotic. Patients reported whether an antibiotic had been prescribed, and pharmacy dispensing records were reviewed to determine whether an antibiotic was dispensed. RESULTS: Participants who viewed either the futility or the adverse effects presentation had greater reductions in their expectations to receive antibiotics than the control group. The mean reduction (95% CI) was 1.1 (0.8-1.3) for the futility group, 0.7 (0.4-0.9) for the adverse effects group, and 0.1 (0-0.3) for the control group (Cohen d = 0.7; P <.001). There was no significant difference among the 3 groups with regard to antibiotic prescribing (P = .84) or dispensing (P = .43). CONCLUSIONS: A brief tablet-based waiting room intervention significantly reduced participants' expectations about receiving antibiotics for URTI immediately before their family practitioner consultation. The intervention did not influence family practitioner prescribing behavior, however.

Conceptual framework for task shifting and task sharing: an international Delphi study.

BACKGROUND: Task shifting and sharing (TS/S) involves the redistribution of health tasks within workforces and communities. Conceptual frameworks lay out the key factors, constructs, and variables involved in a given phenomenon, as well as the relationships between those factors. Though TS/S is a leading strategy to address health worker shortages and improve access to services worldwide, a conceptual framework for this approach is lacking. METHODS: We used an online Delphi process to engage an international panel of scholars with experience in knowledge synthesis concerning TS/S and develop a conceptual framework for TS/S. We invited 55 prospective panelists to participate in a series of questionnaires exploring the purpose of TS/S and the characteristics of contexts amenable to TS/S programmes. Panelist responses were analysed and integrated through an iterative process to achieve consensus on the elements included in the conceptual framework. RESULTS: The panel achieved consensus concerning the included concepts after three Delphi rounds among 15 panelists. The COATS Framework (Concepts and Opportunities to Advance Task Shifting and Task Sharing) offers a refined definition of TS/S and a general purpose statement to guide TS/S programmes. COATS describes that opportunities for health system improvement arising from TS/S programmes depending on the implementation context, and enumerates eight necessary conditions and important considerations for implementing TS/S programmes. CONCLUSION: The COATS Framework offers a conceptual model for TS/S programmes. The COATS Framework is comprehensive and adaptable, and can guide refinements in policy, programme development, evaluation, and research to improve TS/S globally.

The Impact of the Auckland Cellulitis Pathway on Length of Hospital Stay, Mortality Readmission Rate, and Antibiotic Stewardship.

BACKGROUND: The Dundee classification of cellulitis severity, previously shown to predict disease outcomes, provides an opportunity to improve the management of patients with cellulitis. METHODS: We developed and implemented a pathway to guide the management of adults with cellulitis based on their Dundee severity class, and measured its effect on patient outcomes. We compared the outcomes in patients admitted to Auckland City Hospital (ACH) between July 2014 and July 2015 (the baseline cohort) with those in patients admitted between June 2017 and June 2018 (the intervention cohort). RESULTS: The median length of stay was shorter in the intervention cohort (0.7 days, interquartile range (IQR) 0.1 to 3.0 days) than in the baseline cohort (1.8 days, IQR 0.1 to 4.4 days; P < .001). The 30-day mortality rate declined from 1.8% (19/1092) in the baseline cohort to 0.7% (10/1362; P = .02) in the intervention cohort. The 30-day cellulitis readmission rate increased from 6% in the baseline cohort to 11% (P < .001) in the intervention cohort. Adherence to the ACH cellulitis antibiotic guideline improved from 38% to 48% (P < .01) and was independently associated with reduced length of stay. CONCLUSIONS: The implementation of the Auckland cellulitis pathway, readily generalizable to other settings, improved the outcomes in patients with cellulitis, and resulted in an annual saving of approximately 1000 bed days.

Collaborative networks enable the rapid establishment of serological assays for SARS-CoV-2 during nationwide lockdown in New Zealand.

BACKGROUND: Serological assays that detect antibodies to SARS-CoV-2 are critical for determining past infection and investigating immune responses in the COVID-19 pandemic. We established ELISA-based immunoassays using locally produced antigens when New Zealand went into a nationwide lockdown and the supply chain of diagnostic reagents was a widely held domestic concern. The relationship between serum antibody binding measured by ELISA and neutralising capacity was investigated using a surrogate viral neutralisation test (sVNT). METHODS: A pre-pandemic sera panel (n = 113), including respiratory infections with symptom overlap with COVID-19, was used to establish assay specificity. Sera from PCR­confirmed SARS-CoV-2 patients (n = 21), and PCR-negative patients with respiratory symptoms suggestive of COVID-19 (n = 82) that presented to the two largest hospitals in Auckland during the lockdown period were included. A two-step IgG ELISA based on the receptor binding domain (RBD) and spike protein was adapted to determine seropositivity, and neutralising antibodies that block the RBD/hACE­2 interaction were quantified by sVNT. RESULTS: The calculated cut-off (>0.2) in the two-step ELISA maximised specificity by classifying all pre-pandemic samples as negative. Sera from all PCR-confirmed COVID-19 patients were classified as seropositive by ELISA ≥7 days after symptom onset. There was 100% concordance between the two-step ELISA and the sVNT with all 7+ day sera from PCR­confirmed COVID-19 patients also classified as positive with respect to neutralising antibodies. Of the symptomatic PCR-negative cohort, one individual with notable travel history was classified as positive by two-step ELISA and sVNT, demonstrating the value of serology in detecting prior infection. CONCLUSIONS: These serological assays were established and assessed at a time when human activity was severely restricted in New Zealand. This was achieved by generous sharing of reagents and technical expertise by the international scientific community, and highly collaborative efforts of scientists and clinicians across the country. The assays have immediate utility in supporting clinical diagnostics, understanding transmission in high-risk cohorts and underpinning longer­term 'exit' strategies based on effective vaccines and therapeutics.

Genotypic and phenotypic analyses reveal distinct population structures and ecotypes for sugar beet-associated Pseudomonas in Oxford and Auckland.

Fluorescent pseudomonads represent one of the largest groups of bacteria inhabiting the surfaces of plants, but their genetic composition in planta is poorly understood. Here, we examined the population structure and diversity of fluorescent pseudomonads isolated from sugar beet grown at two geographic locations (Oxford, United Kingdom and Auckland, New Zealand). To seek evidence for niche adaptation, bacteria were sampled from three types of leaves (immature, mature, and senescent) and then characterized using a combination of genotypic and phenotypic analysis. We first performed multilocus sequence analysis (MLSA) of three housekeeping genes (gapA, gltA, and acnB) in a total of 152 isolates (96 from Oxford, 56 from Auckland). The concatenated sequences were grouped into 81 sequence types and 22 distinct operational taxonomic units (OTUs). Significant levels of recombination were detected, particularly for the Oxford isolates (rate of recombination to mutation (r/m) = 5.23 for the whole population). Subsequent ancestral analysis performed in STRUCTURE found evidence of six ancestral populations, and their distributions significantly differed between Oxford and Auckland. Next, their ability to grow on 95 carbon sources was assessed using the Biolog™ GN2 microtiter plates. A distance matrix was generated from the raw growth data (A 660) and subjected to multidimensional scaling (MDS) analysis. There was a significant correlation between substrate utilization profiles and MLSA genotypes. Both phenotypic and genotypic analyses indicated presence of a geographic structure for strains from Oxford and Auckland. Significant differences were also detected for MLSA genotypes between strains isolated from immature versus mature/senescent leaves. The fluorescent pseudomonads thus showed an ecotypic population structure, suggestive of adaptation to both geographic conditions and local plant niches.