Living review framework for better policy design and management of hazardous waste in Australia.

The significant increase in hazardous waste generation in Australia has led to the discussion over the incorporation of artificial intelligence into the hazardous waste management system. Recent studies explored the potential applications of artificial intelligence in various processes of managing waste. However, no study has examined the use of text mining in the hazardous waste management sector for the purpose of informing policymakers. This study developed a living review framework which applied supervised text classification and text mining techniques to extract knowledge using the domain literature data between 2022 and 2023. The framework employed statistical classification models trained using iterative training and the best model XGBoost achieved an F1 score of 0.87. Using a small set of 126 manually labelled global articles, XGBoost automatically predicted the labels of 678 Australian articles with high confidence. Then, keyword extraction and unsupervised topic modelling with Latent Dirichlet Allocation (LDA) were performed. Results indicated that there were 2 main research themes in Australian literature: (1) the key waste streams and (2) the resource recovery and recycling of waste. The implication of this framework would benefit the policymakers, researchers, and hazardous waste management organisations by serving as a real time guideline of the current key waste streams and research themes in the literature which allow robust knowledge to be applied to waste management and highlight where the gap in research remains.

Patient Biochemistry and Treatment Need in Chronic Hepatitis B Virus Infection Across Three Continents: Retrospective Cross-Sectional Cohort Studies.

INTRODUCTION: Chronic hepatitis B virus (HBV) infection is associated with significant global morbidity and mortality. Low treatment rates are observed in patients living with HBV; the reasons for this are unclear. This study sought to describe patients' demographic, clinical and biochemical characteristics across three continents and their associated treatment need. METHODS: This retrospective cross-sectional post hoc analysis of real-world data used four large electronic databases from the United States, United Kingdom and China (specifically Hong Kong and Fuzhou). Patients were identified by first evidence of chronic HBV infection in a given year (their index date) and characterized. An algorithm was designed and applied, wherein patients were categorized as treated, untreated but indicated for treatment and untreated and not indicated for treatment based on treatment status and demographic, clinical, biochemical and virological characteristics (age; evidence of fibrosis/cirrhosis; alanine aminotransferase [ALT] levels, HCV/HIV coinfection and HBV virology markers). RESULTS: In total, 12,614 US patients, 503 UK patients, 34,135 patients from Hong Kong and 21,614 from Fuzhou were included. Adults (99.4%) and males (59.0%) predominated. Overall, 34.5% of patients were treated at index (range 15.9-49.6%), with nucleos(t)ide analogue monotherapy most commonly prescribed. The proportion of untreated-but-indicated patients ranged from 12.9% in Hong Kong to 18.2% in the UK; almost two-thirds of these patients (range 61.3-66.7%) had evidence of fibrosis/cirrhosis. A quarter (25.3%) of untreated-but-indicated patients were aged ≥ 65 years. CONCLUSION: This large real-world dataset demonstrates that chronic hepatitis B infection remains a global health concern; despite the availability of effective suppressive therapy, a considerable proportion of predominantly adult patients apparently indicated for treatment are currently untreated, including many patients with fibrosis/cirrhosis. Causes of disparity in treatment status warrant further investigation.

Characteristics, Treatment Patterns, and Clinical Outcomes of Chronic Hepatitis B Across 3 Continents: Retrospective Database Study.

INTRODUCTION: The prevalence of chronic hepatitis B virus (HBV) infection is high in many countries; however, robust, real-world epidemiological data are lacking. This study describes the prevalence, characteristics, treatment patterns, and long-term clinical outcomes of patients with chronic HBV infection in the US, Germany, and Taiwan. METHODS: This was a retrospective cohort analysis of three healthcare/insurance claims databases. Individuals were identified as patients with chronic HBV infection if their records contained HBV diagnostic codes from 1 January 2010 to 31 December 2012 (Germany and Taiwan) or 1 January 2013 (USA). Included patients were indexed on 1 January 2013. Patients' demographics, clinical characteristics, and healthcare utilisation were described. Treatment patterns and long-term clinical outcomes over follow-up (to 31 December 2016 or loss to follow-up) were estimated. RESULTS: The prevalence of chronic HBV infection was 0.10%, 0.17%, and 2.39% in the US, Germany, and Taiwan respectively. Prevalence was very low in children, increased rapidly in adulthood, and peaked in 50- < 65 year olds before declining in the elderly. More US (16.6%) and German (15.4%) patients were HIV ± HCV coinfected than in Taiwan (4.1%). Baseline clinical characteristics and healthcare utilisation were broadly similar between countries. In total, 19.2%, 11.1%, and 5.9% of non-coinfected adult patients received treatment at index in the US, Germany, and Taiwan, respectively; most frequently with nucleos(t)ide analogue monotherapy (94.4%, 97.2%, 99.8% of treated patients, respectively) and rarely with interferons (0.27%, 1.63%, and 0.06%, respectively). Untreated Taiwanese patients were more likely to remain untreated than elsewhere, and treated Taiwanese patients were less likely to persist with therapy. Generally, the cumulative incidence of long-term clinical outcomes was lowest in Germany. CONCLUSION: This study provides a contemporary, real-world, intercontinental snapshot of chronic HBV infection. Long-term sequelae occurred in all populations, and treatment levels were low, suggesting an unmet need for (or access to) effective treatments.

Using Climate-HIV to describe real-world clinical outcomes for people living with HIV taking dolutegravir-based regimens.

OBJECTIVES: The objective of this study was to describe the real-world use and effectiveness of dolutegravir-based regimens (DBRs) in routine clinical practice in the United Kingdom. METHODS: Retrospective analysis was conducted using data from four National Health Service trusts using Climate-HIV, an electronic case record system. Eligible patients were aged ≥18 years with HIV-1 infection who were prescribed a DBR from December 2012 to March 2018. Outcome measurements were accessed at DBR initiation and at weeks 24, 48 and 96 and the last recorded visit up to the extraction date (last measurement). The primary endpoint was the proportion of patients with HIV-1 RNA <50 copies/mL at Week 48. RESULTS: The study cohort included 934 patients; 337 (36%) were female, 414 (47%) were white and 717 (77%) were treatment experienced (TE). The Kaplan-Meier estimated probability of achieving HIV-1 RNA <50 copies/mL at 48 weeks was 96% for treatment-naive (TN) patients and 86% for TE patients. Median times to viral suppression (<50 copies/mL) were 49 and 57 days for TN and TE patients with detectable baseline viral load, respectively, according to Kaplan-Meier analysis. Median follow-up time was 377 days (interquartile range: 131-683). At last measurement, 87% (809/934) of patients remained on a DBR; among those patients, 681 (84%) had HIV-1 RNA <50 copies/mL. CONCLUSIONS: High levels of virologic suppression and low rates of discontinuation of DBRs were seen in a large, diverse, UK-based population with HIV-1 infection. These findings are broadly consistent with efficacy data from phase III studies.

Persistence and Adherence to ICS/LABA Drugs in UK Patients with Asthma: A Retrospective New-User Cohort Study.

INTRODUCTION: Asthma is associated with significant economic burden. Inhaled corticosteroid and long-acting beta2-agonist (ICS/LABA) combination therapies are considered mainstays of treatment. We describe real-world use of ICS/LABAs by comparing treatment persistence and adherence among patients with asthma in the United Kingdom initiating fluticasone furoate/vilanterol (FF/VI) versus budesonide/formoterol (BUD/FM) or beclometasone dipropionate/formoterol (BDP/FM). METHODS: A retrospective new-user active comparator database study was conducted in the IQVIA Medical Research Database. Propensity score (PS) matching was performed for FF/VI versus BUD/FM, and FF/VI versus BDP/FM. The primary objective was to compare patient treatment persistence (time to discontinuation), while secondary objectives included assessing adherence (mean proportion of days covered [PDC] with medication in the study period) and the proportions of patients achieving ≥ 50% and ≥ 80% PDC. RESULTS: New users of FF/VI (N = 966), BUD/FM (N = 5931) and BDP/FM (N = 9607) were identified and PS-matched: FF/VI (n = 945) versus BUD/FM (n = 3272), and FF/VI (n = 902) versus BDP/FM (n = 3465). At 12 months, treatment persistence was 69% (FF/VI), 53% (BUD/FM) and 57% (BDP/FM). The likelihood of treatment discontinuation within 12 months after initiation with FF/VI was 35% lower than with BUD/FM and 31% lower than for BDP/FM (both p < 0.001). Mean PDC was higher for FF/VI compared with BUD/FM (77.7 vs 72.4; p < 0.0001) and BDP/FM (78.2 vs 71.0; p < 0.0001). The odds of achieving ≥ 50% and ≥ 80% PDC were greater for FF/VI than for BUD/FM and BDP/FM. CONCLUSIONS: In this study, patients who initiated FF/VI were less likely to discontinue treatment and showed greater treatment adherence versus patients who initiated BUD/FM or BDP/FM.

Prevalence of anal fistula in the United Kingdom.

BACKGROUND: Anal fistula is a pathological connection between the anal canal and perianal skin, which most commonly develops from an infected anal crypt. While the majority of anal fistulas are idiopathic, they are also associated with Crohn's disease (CD) and other inflammatory conditions. The prevalence of anal fistula is estimated to be 1-2 per 10000 patients, but population-based studies on anal fistula epidemiology are limited and outdated. AIM: To assess the prevalence of anal fistula and relevant comorbidities, with and without CD in the United Kingdom and Europe. METHODS: A retrospective population-representative observational cohort study was performed in The Health Improvement Network (THIN), a United Kingdom primary care database. Mid-year point prevalence of anal fistula was calculated on the first of July for each year between 2014 and 2017. Estimates were calculated for anal fistula overall and by CD status and standardized to the United Kingdom and European population. Prevalence of relevant comorbidities including lymphogranuloma venereum, hidradenitis suppurativa, anal presentation of sexually transmitted diseases, diabetes mellitus, and radiation in the pelvic area was reported. RESULTS: The United Kingdom-standardized overall point prevalence of anal fistula was 1.80 (95%CI: 1.65-1.94) per 10000 patients in 2017, while the Europe standardized estimate was 1.83 (95%CI: 1.68-1.98) per 10000 patients. Both these standardized point prevalence estimates ranged from 1.89 to 2.36 between 2014-2016. The United Kingdom-standardized point prevalence of anal fistula without CD was 1.35 (95%CI: 1.23-1.48) per 10000 patients, while the Europe-standardized estimate was 1.39 (95%CI: 1.26-1.52) per 10000 patients. In contrast, the standardized point prevalence estimate of anal fistula with CD was lower for both United Kingdom and Europe (0.44; 95%CI United Kingdom: 0.37-0.52, 95%CI Europe: 0.37-0.51) per 10000 patients in 2017. In 2017, 19% of anal fistula patients without CD and 13% of anal fistula patients with CD had at least one relevant comorbidity. These results show that anal fistulas are infrequent in the general population. 24.5% of prevalent anal fistulas are associated with CD, but other potentially etiological comorbidities are rare. CONCLUSION: This real-world evidence study estimated the United Kingdom-standardized prevalence of anal fistula was 1.80 per 10000 patients in 2017. Approximately 25% of cases may be associated with CD, while other comorbidities are rare.

No increased risk of nephrotoxicity associated with 5-aminosalicylic acid in IBD: a population-based cohort and nested case-control study.

BACKGROUND: There is conflicting evidence about nephrotoxicity risk associated with 5-aminosalicylates for treatment of IBD. AIMS: To determine population-based temporal trends for 5-aminosalicylates and estimated risk of nephrotoxicity associated with 5-aminosalicylate use for ulcerative colitis (UC) and Crohn's disease (CD). METHODS: Retrospective cohort and nested case-control study, using the Health Improvement Network primary care database linked to hospital discharge coding for patients in England, 1996-2017. Nephrotoxicity risk analysis was a first recorded renal impairment diagnosis adjusted for key variables and was assessed between 2008 and 2017. RESULTS: A total of 35 601 patients with prevalent UC or CD were included. The proportion of patients prescribed 5-aminosalicylates fell from 83% in 1996-1999 to 71% in 2012-2015 for UC patients and 64% to 45% for CD patients. Thirty per cent of patients had prolonged 5-aminosalicylate use. Between 2008 and 2017, the incident rate of nephrotoxicity was similar and stable for UC (12.6/1000 person-years) and CD (10.9/1000 person-years) patients. Multivariate analysis showed no evidence for association between current prescription of 5-aminosalicylate and nephrotoxicity in UC or CD patients, comparing ≤ 30 days prescription prior to index vs 31-≤180 days. However, active disease, disease duration, concomitant cardiovascular disease or diabetes and nephrotoxic drug use were independently associated with development of nephrotoxicity in UC and CD. CONCLUSIONS: Despite the paucity of evidence for their benefit, 5-aminosalicylates were prescribed to approximately half of CD patients (30% prolonged therapy). Nephrotoxicity was rare in this patient cohort, and was not associated with 5-aminosalicylate use, but rather with disease status, comorbidity and use of nephrotoxic drugs.

Genome-based classification of two halotolerant extreme acidophiles, Acidihalobacter prosperus V6 (=DSM 14174 =JCM 32253) and 'Acidihalobacter ferrooxidans' V8 (=DSM 14175 =JCM 32254) as two new species, Acidihalobacter aeolianus sp. nov. and Acidihalobacter ferrooxydans sp. nov., respectively.

Phylogenomic analysis of recently released high-quality draft genome sequences of the halotolerant acidophiles, Acidihalobacter prosperus V6 (=DSM 14174=JCM 32253) and 'Acidihalobacter ferrooxidans' V8 (=DSM 14175=JCM 32254), was undertaken in order to clarify their taxonomic relationship. Sequence based phylogenomic approaches included 16S rRNA gene phylogeny, multi-gene phylogeny from the concatenated alignment of nine selected housekeeping genes and multiprotein phylogeny using clusters of orthologous groups of proteins from ribosomal protein families as well as those from complete sets of markers based on concatenated alignments of universal protein families. Non-sequence based approaches for species circumscription were based on analyses of average nucleotide identity, which was further reinforced by the correlation indices of tetra-nucleotide signatures as well as genome-to-genome distance (digital DNA-DNA hybridization) calculations. The different approaches undertaken in this study for species tree reconstruction resulted in a tree that was phylogenetically congruent, revealing that both micro-organisms are members of separate species of the genus Acidihalobacter. In accordance, it is proposed that A. prosperus V6T (=DSM 14174 T=JCM 32253 T) be formally classified as Acidihalobacter aeolianus sp. nov., and 'Acidihalobacter ferrooxidans' V8T (=DSM 14175 T=JCM 32254 T) as Acidihalobacter ferrooxydans sp. nov., and that both represent the type strains of their respective species.

Application of indirect non-contact bioleaching for extracting metals from waste lithium-ion batteries.

Applying biohydrometallurgy for metal extraction and recovery from mixed and polymetallic wastes such as electronic waste is limited due to microbial inhibition at low pulp densities and substrate (iron and sulfur) limitation. Here, we investigated the application of indirect non-contact bioleaching with biogenic ferric iron and sulfuric acid to extract metals from lithium-ion battery (LIB) waste. Results showed that although a single leach stage at ambient temperature only facilitated low leach yields (<10%), leach yields for all metals improved with multiple sequential leach stages (4 × 1 h). Biogenic ferric leaching augmented with 100 mM H2SO4 further enabled the highest leach yields (53.2% cobalt, 60.0% lithium, 48.7% nickel, 81.8% manganese, 74.4% copper). The proposed use of bioreagents is a viable and a more environmentally benign alternative to traditional mineral processing, which could be further improved by appropriate pre-treatment of the LIB waste.

Quantitative proteomics using SWATH-MS identifies mechanisms of chloride tolerance in the halophilic acidophile Acidihalobacter prosperus DSM 14174.

In this study, the differential protein expression of the acidophilic halophile, Acidihalobacter prosperus DSM 14174 (strain V6) was studied with the aim of understanding its mechanisms of tolerance to high chloride ion stress in the presence of low pH, using Sequential Window Acquisition of all Theoretical Mass Spectra (SWATH-MS). In acidophiles, chloride stress results in both osmotic stress as well as acidification of the cytoplasm due to the ability of chloride to permeate the cell membrane and disrupt the reversed transmembrane potential which normally extrudes protons. The proteomic response of A. prosperus DSM 14174 to elevated chloride concentrations included the production of osmotic stress regulators that potentially induced the production of compatibles solutes, of which the most significant increase was in the synthesis of ectoine. Other responses directly related to the increased chloride and acid stress, included the increased synthesis of glutathione, changes in carbon flux, the increased production of amino acids, the decreased production of ribosomal proteins, the efflux of metals and protons, and the increase in proteins involved in DNA repair and membrane biosynthesis. Energy generation through iron oxidation and sulphur oxidation were decreased, and energy was probably obtained from the metabolism of glycogen stores. Overall, these studies have helped to create a model of tolerance to elevated chloride under acidic conditions by A. prosperus DSM 14174 that differs from the previous model developed for the type strain, A. prosperus DSM 5130T.

In a quest for engineering acidophiles for biomining applications: challenges and opportunities.

Biomining with acidophilic microorganisms has been used at commercial scale for the extraction of metals from various sulfide ores. With metal demand and energy prices on the rise and the concurrent decline in quality and availability of mineral resources, there is an increasing interest in applying biomining technology, in particular for leaching metals from low grade minerals and wastes. However, bioprocessing is often hampered by the presence of inhibitory compounds that originate from complex ores. Synthetic biology could provide tools to improve the tolerance of biomining microbes to various stress factors that are present in biomining environments, which would ultimately increase bioleaching efficiency. This paper reviews the state-of-the-art tools to genetically modify acidophilic biomining microorganisms and the limitations of these tools. The first part of this review discusses resilience pathways that can be engineered in acidophiles to enhance their robustness and tolerance in harsh environments that prevail in bioleaching. The second part of the paper reviews the efforts that have been carried out towards engineering robust microorganisms and developing metabolic modelling tools. Novel synthetic biology tools have the potential to transform the biomining industry and facilitate the extraction of value from ores and wastes that cannot be processed with existing biomining microorganisms.

Complete genome sequence of Acidihalobacter prosperus strain F5, an extremely acidophilic, iron- and sulfur-oxidizing halophile with potential industrial applicability in saline water bioleaching of chalcopyrite.

Successful process development for the bioleaching of mineral ores, particularly the refractory copper sulfide ore chalcopyrite, remains a challenge in regions where freshwater is scarce and source water contains high concentrations of chloride ion. In this study, a pure isolate of Acidihalobacter prosperus strain F5 was characterized for its ability to leach base metals from sulfide ores (pyrite, chalcopyrite and pentlandite) at increasing chloride ion concentrations. F5 successfully released base metals from ores including pyrite and pentlandite at up to 30gL-1 chloride ion and chalcopyrite up to 18gL-1 chloride ion. In order to understand the genetic mechanisms of tolerance to high acid, saline and heavy metal stress the genome of F5 was sequenced and analysed. As well as being the first strain of Ac. prosperus to be isolated from Australia it is also the first complete genome of the Ac. prosperus species to be sequenced. The F5 genome contains genes involved in the biosynthesis of compatible solutes and genes encoding monovalent cation/proton antiporters and heavy metal transporters which could explain its abilities to tolerate high salinity, acidity and heavy metal stress. Genome analysis also confirmed the presence of genes involved in copper tolerance. The study demonstrates the potential biotechnological applicability of Ac. prosperus strain F5 for saline water bioleaching of mineral ores.

Draft Genome Sequence of Acidihalobacter ferrooxidans DSM 14175 (Strain V8), a New Iron- and Sulfur-Oxidizing, Halotolerant, Acidophilic Species.

The use of halotolerant acidophiles for bioleaching provides a biotechnical approach for the extraction of metals from regions where high salinity exists in the ores and source water. Here, we describe the first draft genome of a new species of a halotolerant and iron- and sulfur-oxidizing acidophile, Acidihalobacter ferrooxidans DSM 14175 (strain V8).

Draft Genome Sequence of the Acidophilic, Halotolerant, and Iron/Sulfur-Oxidizing Acidihalobacter prosperus DSM 14174 (Strain V6).

The principal genomic features of Acidihalobacter prosperus DSM 14174 (strain V6) are presented here. This is a mesophilic, halotolerant, and iron/sulfur-oxidizing acidophile that was isolated from seawater at Vulcano, Italy. It has potential for use in biomining applications in regions where high salinity exists in the source water and ores.

Evaluation of exposure to pioglitazone and risk of prostate cancer: a nested case-control study.

OBJECTIVES: Investigate potential association between pioglitazone exposure and risk of prostate cancer. RESEARCH DESIGN AND METHODS: Nested, matched case-control study. UK primary care data (Clinical Practice Research Datalink (CPRD) GOLD) linked to inpatient (Hospital Episode Statistics (HES)) and cancer registry (National Cancer Information Network (NCIN)) data. English men aged ≥40 years diagnosed with type 2 diabetes mellitus, January 1, 2001 to January 5, 2015. Cases, with prostate cancer diagnosis, matched with up to 4 controls by age, cohort entry date and region. ORs for association of exposure to pioglitazone to incident prostate cancer, adjusted for potential confounders. RESULTS: From a cohort of 47 772 men with 243 923 person-years follow-up, 756 definite cases of prostate cancer were identified. Incidence was 309.9/100 000 person-years (95% CI 288.6 to 332.8). Pioglitazone use was not associated with prostate cancer risk; adjusted OR 0.759, 95% CI 0.502 to 1.148. Analyses showed no difference when possible cases, prostate cancer in CPRD GOLD only, included (adjusted OR 0.726, 95% CI 0.510 to 1.034). No association when adjusted for channeling bias (OR 0.778, 95% CI 0.511 to 1.184) or limited to an index date prior to July 1, 2011 (adjusted OR 0.508, 95% CI 0.294 to 0.879), despite prostate-specific antigen screening occurring more frequently among cases than controls (81.6% of 756 definite cases cf. 24.2% of 2942 controls (p<0.01)). No association with duration of pioglitazone use, increasing pioglitazone dose or increasing time since initiation. CONCLUSIONS: In this real-world, nested matched case-control study, exposure to pioglitazone was not associated with increased risk of prostate cancer.

Increased measles-mumps-rubella (MMR) vaccine uptake in the context of a targeted immunisation campaign during a measles outbreak in a vaccine-reluctant community in England.

BACKGROUND: Following a measles outbreak in a vaccine-rejecting community between April and September 2011 in South-East England, local health agencies implemented a two-pronged measles-mumps-rubella (MMR) immunisation campaign from August to October offered at the local general practice where most cases were registered. The campaign included (a) accelerated vaccination of children earlier than scheduled (1st dose at 6-11 months, or 2nd dose at 18-39 months), (b) catch-up of those aged over 18 months who had had no MMR immunisations or were late for second MMR. We investigated the impact of the outbreak and campaign on the number of MMR doses given. MATERIALS AND METHODS: In January 2012, we collected information on MMR vaccination for children registered at the practice aged 6 months-16 years on 1 August 2011, through the child health information system. We counted the number of MMR doses administered in 2011 and compared it to 2008-2010 data. We estimated the proportion vaccinated among the children eligible for the accelerated and catch-up campaign. RESULTS: The local practice administered 257 MMR doses in 2011, a 114% increase on the average for 2008-2010. Among children eligible for earlier MMR vaccination 5/26 (19%) received a first dose, and 34/57 (60%) a second dose. Among children eligible for catch-up, 20/329 (6%) received their first MMR and 39/121 (32%) their second. Of 1538 children, the proportion completely unimmunised for MMR declined by 3 percentage-points after the outbreak. DISCUSSION: Uptake of MMR vaccination significantly increased during the outbreak following the immunisation campaign. Those amenable to MMR vaccination seem to have benefited from the campaign more than those with no previous vaccinations. Future evaluations should address what made a few parents change their mind and have their children vaccinated for the first time during the outbreak.

Poliomyelitis outbreak, Pointe-Noire, Republic of the Congo, September 2010-February 2011.

On November 4, 2010, the Republic of the Congo declared a poliomyelitis outbreak. A cross-sectional survey in Pointe-Noire showed poor sanitary conditions and low vaccination coverage (55.5%), particularly among young adults. Supplementary vaccination should focus on older age groups in countries with evidence of immunity gaps.

Application of pulsed-field gel electrophoresis to identify potential outbreaks of campylobacteriosis in New Zealand.

Since 2002, New Zealand's incidence of campylobacteriosis has exceeded 300 cases per 100,000 people per annum. To evaluate genetic variation in human isolates, 183 Campylobacter isolates were collected from a single clinical laboratory in Christchurch: 77 during an 8-week period in spring, and the rest 3 months later over a second 8-week period in autumn. Isolates were identified to the species level and subtyped using Penner serotyping (Campylobacter jejuni only) and pulsed-field gel electrophoresis (PFGE) using both SmaI and KpnI. Approximately two-thirds of the isolates could be grouped into clusters of between 2 and 26 isolates with indistinguishable SmaI and KpnI patterns. Less than 10% of the isolates were of the same type between the two sampling periods. The epidemiological relevance of the PFGE clusters was supported by temporal clustering, some spatial clustering, and some statistically significant demographic similarities among cases in a cluster. Conversely, patient cases yielding isolates which did not cluster with isolates from other cases were more likely to report recent overseas travel and less likely to live within larger urban centers. To identify whether these clusters actually represent common-source outbreaks, however, would require the detailed, rapid, and reiterative epidemiological investigation of cases within a PFGE cluster. The combined and timely application of subtyping and epidemiological investigation would appear to be a promising strategy for understanding campylobacteriosis in New Zealand.