Epidemiological investigation of a severe rumen fluke outbreak on an Irish dairy farm.

Although the rumen fluke, Calicophoron daubneyi is now very common and widespread throughout Western Europe, reports of clinical cases are still rare. This study explores the epidemiological background to a severe rumen fluke outbreak in 6-month-old heifers on a dairy farm in Ireland. Sequence analysis of the cytochrome oxidase subunit 1 (Cox1) gene of the rumen fluke metacercariae on pasture failed to identify predominant, possibly pathogenic subtypes. However, estimates of metacercarial load indicated that the animals were exposed to a daily dose of about 5334 C. daubneyi metacercariae for a period of 3 weeks resulting in the build-up of very large numbers of immature worms in the small intestine. It is hypothesized that specific environmental conditions may favour this parasite over its competitor, the liver fluke, Fasciola hepatica, possibly by allowing it to emerge earlier. The possibility that C. daubneyi may be better adapted to the Irish climate than F. hepatica together with the fact that selective treatment against F. hepatica effectively frees the niche for C. daubneyi, may result in the gradual replacement of F. hepatica by C. daubneyi.

Streptococcus pneumoniae and Haemophilus influenzae in paediatric meningitis patients at Goroka General Hospital, Papua New Guinea: serotype distribution and antimicrobial susceptibility in the pre-vaccine era.

BACKGROUND: Bacterial meningitis remains an important infection globally, with the greatest burden in children in low-income settings, including Papua New Guinea (PNG). We present serotype, antimicrobial susceptibility and outcome data from paediatric meningitis patients prior to introduction of Haemophilus influenzae type b (Hib) and pneumococcal conjugate vaccines (PCVs) in PNG, providing a baseline for evaluation of immunisation programs. METHODS: Cerebrospinal fluid (CSF) was collected from children admitted to Goroka General Hospital with suspected meningitis between 1996 and 2005. Culture and sensitivity was conducted, and pneumococci and H. influenzae were serotyped. Laboratory findings were linked to clinical outcomes. RESULTS: We enrolled 1884 children. A recognised pathogen was identified in 375 children (19.9%). Streptococcus pneumoniae (n = 180) and Hib (n = 153) accounted for 88.8% of pathogens isolated. 24 different pneumococcal serogroups were identified; non-PCV types 2, 24 and 46 accounted for 31.6% of pneumococcal meningitis. 10- and 13-valent PCVs would cover 44.1% and 45.4% of pneumococcal meningitis respectively. Pneumococcal isolates were commonly resistant to penicillin (21.5%) and 23% of Hib isolates were simultaneously resistant to ampicillin, co-trimoxazole and chloramphenicol. The case fatality rate in patients with a recognised bacterial pathogen was 13.4% compared to 8.5% in culture-negative patients. CONCLUSIONS: If implemented in routine expanded programme of immunisation (EPI) with high coverage, current PCVs could prevent almost half of pneumococcal meningitis cases. Given the diversity of circulating serotypes in PNG serotype replacement is of concern. Ongoing surveillance is imperative to monitor the impact of vaccines. In the longer term vaccines providing broader protection against pneumococcal meningitis will be needed.

The nursing quality partnership: building a health system approach to improving care in community hospitals using principles of the magnet program of excellence.

Review of the Magnet Recognition Program journey related to the partnership between nursing and quality in building a comprehensive, results-driven quality and safety program in a 5 hospital community system in suburban Philadelphia over a 5-year period (2006-2011).

Protective immunity against tuberculosis in a free-living badger population vaccinated orally with Mycobacterium bovis Bacille Calmette-Guérin.

Vaccination of badgers with Mycobacterium bovis Bacille Calmette-Guérin (BCG) has been shown to protect badgers against tuberculosis in experimental trials. During the 3-year County Kilkenny BCG vaccine field study, badgers were treated orally with placebo (100% in Zone A), BCG (100% in Zone C) or randomly assigned 50%: 50% treatment with BCG or placebo (Zone B). At the end of the study, 275 badgers were removed from the trial area and subjected to detailed post-mortem examination followed by histology and culture for M. bovis. Among these badgers, 83 (30.2%) were captured for the first time across the three zones, representing a non-treated proportion of the population. Analysis of the data based on the infection status of treated animals showed a prevalence of 52% (95% CI: 40%-63%) infection in Zone A (placebo), 39% (95% CI: 17%-64%) in Zone B (placebo) and 44% (95% CI: 20%-70%) in Zone B (BCG vaccinated) and 24% (95% CI: 14%-36%) in Zone C (BCG vaccinated). There were no statistically significant differences in the proportion of animals with infection involving the lung and thoracic lymph nodes, extra-thoracic infection or in the distribution and severity scores of histological lesions. Among the 83 non-treated badgers removed at the end of the study, the infection prevalence of animals in Zone A (prevalence = 46%, 95% CI: 32%-61%) and Zone B (prevalence = 44%, 95% CI: 23%-67%) was similar to the treated animals in these zones. However, in Zone C, no evidence of infection was found in any of the untreated badgers (prevalence = 0%, 95% CI: 0%-14%). This is consistent with an indirect protective effect in the non-vaccinated badgers leading to a high level of population immunity. The results suggest that BCG vaccination of badgers could be a highly effective means of reducing the incidence of tuberculosis in badger populations.

The changing epidemiology of invasive pneumococcal disease in aboriginal and non-aboriginal western Australians from 1997 through 2007 and emergence of nonvaccine serotypes.

BACKGROUND. In 2001, Australia introduced a unique 7-valent pneumococcal conjugate vaccine (7vPCV) 2-, 4-, and 6-month schedule with a 23-valent pneumococcal polysaccharide vaccine (23vPPV) booster for Aboriginal children, and in 2005, 7vPCV alone in a 2-, 4-, and 6-month schedule for non-Aboriginal children. Aboriginal adults are offered 23vPPV but coverage is poor. We investigated trends in invasive pneumococcal disease (IPD) in Western Australia (WA). METHODS. Enhanced IPD surveillance has been ongoing since 1996. We calculated IPD incidence rates for Aboriginal and non-Aboriginal Australians before and after introduction of 7vPCV. RESULTS. A total of 1792 cases occurred during the period 1997-2007; the IPD incidence rate was 47 cases per 100,000 population per year among Aboriginal people and 7 cases per 100,000 population per year in non-Aboriginal people. After introduction of 7vPCV, IPD rates among Aboriginal children decreased by 46% for those <2 years of age and by 40% for those 2-4 years of age; rates decreased by 64% and 51% in equivalent age groups for non-Aboriginal children. IPD rates decreased by >30% in non-Aboriginal people 50 years of age but increased among Aboriginal adults (eg, from 59.1 to 109.6 cases per 100,000 population per year among those 30-49 years of age). Although IPD due to 7vPCV serotypes decreased in all age groups, IPD incidence due to non-7vPCV serotypes increased, and it almost doubled among Aboriginal adults 30-49 years of age (from 48.3 to 97.0 cases per 100,000 population per year). Among non-Aboriginal children, 37% of IPD is now due to serotype 19A. CONCLUSIONS. IPD incidence rates have decreased markedly among children and non-Aboriginal adults with a 3-dose infant 7vPCV schedule. However, IPD due to non-7vPCV serotypes has increased and is of particular concern among young Aboriginal adults, for whom an intensive 23vPPV campaign is needed. An immunization register covering all age groups should be established.

Modeling and mitigation of high-concentration antibody viscosity through structure-based computer-aided protein design.

For an antibody to be a successful therapeutic many competing factors require optimization, including binding affinity, biophysical characteristics, and immunogenicity risk. Additional constraints may arise from the need to formulate antibodies at high concentrations (>150 mg/ml) to enable subcutaneous dosing with reasonable volume (ideally <1.0 mL). Unfortunately, antibodies at high concentrations may exhibit high viscosities that place impractical constraints (such as multiple injections or large needle diameters) on delivery and impede efficient manufacturing. Here we describe the optimization of an anti-PDGF-BB antibody to reduce viscosity, enabling an increase in the formulated concentration from 80 mg/ml to greater than 160 mg/ml, while maintaining the binding affinity. We performed two rounds of structure guided rational design to optimize the surface electrostatic properties. Analysis of this set demonstrated that a net-positive charge change, and disruption of negative charge patches were associated with decreased viscosity, but the effect was greatly dependent on the local surface environment. Our work here provides a comprehensive study exploring a wide sampling of charge-changes in the Fv and CDR regions along with targeting multiple negative charge patches. In total, we generated viscosity measurements for 40 unique antibody variants with full sequence information which provides a significantly larger and more complete dataset than has previously been reported.

Multilocus genetic analysis reveals that the Australian strains of Vibrio cholerae O1 are similar to the pre-seventh pandemic strains of the El Tor biotype.

Episodes of cholera stemming from indigenous Vibrio cholerae strains in Australia are mainly associated with environmental sources. In the present study, 10 V. cholerae O1 strains of Australian origin were characterized. All of the strains were serogroup O1 and their conventional phenotypic traits categorized them as belonging to the El Tor biotype. Genetic screening of 12 genomic regions that are associated with virulence in V. cholerae showed variable results. Analysis of the ctxAB gene showed that the Australian environmental reservoir contains both toxigenic and non-toxigenic V. cholerae strains. DNA sequencing revealed that all of the toxigenic V. cholerae strains examined were of ctxB genotype 2. Whole genome PFGE analysis revealed that the environmental toxigenic V. cholerae O1 strains were more diverse than the non-toxigenic environmental O1 strains, and the absence of genes that make up the Vibrio seventh pandemic island-I and -II in all of the strains indicates their pre-seventh pandemic ancestry.

An assessment of injury to European badgers (meles meles) due to capture in stopped restraints.

As part of ongoing culling operations, European badgers (Meles meles) were captured using stopped restraints in winter (October to December 2005) and summer (May to June 2006) in the Republic of Ireland. A subset of these badgers, those caught during four consecutive nights, was examined postmortem to determine the frequency and severity of physical injuries resulting from capture in the restraints. The skin and the tissues underlying the restraint of 343 badgers were assessed for injury by visual examination. There was an absence of skin damage or only minor skin abrasions in 88% of badgers; an absence of subcutaneous tissue injury or only localized subcutaneous tissue injury in 69%; and an absence of muscle injury or only slight muscle bruising in 99% of badgers. Only 2% of badgers had cuts to the skin and 5.5% had extensive subcutaneous edema, whereas 1.2% had areas of hemorrhage and tearing of the underlying muscle. Our results show that the majority of badgers examined sustained minimal injuries attributable to capture in stopped restraints.

Bronchoalveolar lavage cytology from captive badgers.

BACKGROUND: Bronchoalveolar lavage (BAL) fluid is evaluated for the diagnosis and study of lung disease and airway inflammation. Cytologic profiles for BAL fluid have not been reported for badgers and may be useful in understanding the pathogenesis of pulmonary diseases such as Mycobacterium bovis. OBJECTIVE: The aim of this study was to evaluate cytologic and microbial findings in BAL fluid from captive European badgers (Meles meles) and identify correlates with the results of concurrently collected blood and fecal samples. METHODS: BAL fluid (by a nonbronchoscopic method) and jugular venous blood samples (for routine CBC) were obtained from 23 captive tuberculosis-free anesthetized badgers on 2 occasions 4 weeks apart. Fecal samples were collected for routine parasitology. Morphologic evaluation and 100-cell differentials were done on cytocentrifuged BAL specimens. Pellets from centrifuged BAL were aerobically cultured for bacteria. RESULTS: With the 2 BAL samples from each of the 23 badgers combined, the median (range) cell percentages were 73.0% (5-95%) neutrophils, 7.5% (2-16%) macrophages, 8.0% (0-27%) lymphocytes, and 9.5% (0-92%) eosinophils. Macrophages frequently contained silica-like crystals. Other findings included ciliated epithelial cells, goblet cells, mucus, and Aelurostrongylus sp. larvae. A light growth of Streptococcus, Pasteurella, or Escherichia coli was cultured in 6 badgers. Trypanosoma pestanai were identified in blood from 10 badgers and fecal parasites (mainly coccidia) were found in 20 badgers. No correlation was found between BAL and CBC results and the presence of parasites. CONCLUSIONS: The predominance of neutrophils in BAL fluid from badgers differs from the predominance of macrophages found in BAL from other species. This difference may reflect the burrowing lifestyle or the unique immune response of badgers.

A Decade of Preventing Harm.

Medical errors are a significant source of morbidity and mortality, and while focused efforts to prevent harm have been made, sustaining reductions across multiple categories of patient harm remains a challenge. In 2008 BJC HealthCare initiated a systemwide program to eliminate all major causes of preventable harm and mortality over a five-year period with a goal of sustaining these reductions over the subsequent five years. METHODS: Areas of focus included pressure ulcers, adverse drug events, falls with injury, health care-associated infections, and venous thromboembolism. Initial efforts involved building system-level multidisciplinary teams, utilizing standardized project management methods, and establishing standard surveillance methods. Evidence-based interventions were deployed across the system; core standards were established while allowing for flexibility in local implementation. Improvements were tracked using actual numbers of events rather than rates to increase meaning and interpretability by patients and frontline staff. RESULTS: Over the course of the five-year intervention period, total harm events were reduced by 51.6% (10,371 events in 2009 to 5,018 events in 2012). Continued improvement efforts over the subsequent five years led to additional harm reduction (2,605 events in 2017; a 74.9% reduction since 2009). CONCLUSION: A combination of project management discipline, rigorous surveillance, and focused interventions, along with system-level support of local hospital improvement efforts, led to dramatic reductions in preventable harm and long-term sustainment of progress.

Descriptive analysis of ovine mortality in sentinel sheep flocks in Ireland.

BACKGROUND: Studies of sheep mortality or cause-specific mortality, in Ireland or internationally, are relatively scarce but are important in presenting baseline levels and changing trends of endemic disease. This study assessed sheep mortality and cause-specific mortality in 33 sentinel sheep flocks in Ireland. METHODS: Sentinel flocks were requested to submit carcases of all sheep that died to the regional veterinary laboratories (RVLs) of the Department of Agriculture, Food and Marine during a calendar year (2016). Postmortem examinations were performed on 1247 submissions to Athlone, Kilkenny and Sligo RVLs. RESULTS: The median overall submission rate was 13.8 per cent (range 2.5 per cent-35.8 per cent) per adult female sheep in the flock in January 2016. The median fetal, perinatal, lamb and adult submissions per adult female sheep in the flock in January 2016 were 2.1 per cent (0.0 per cent-15.2 per cent), 3.5 per cent (0.0 per cent-20.0 per cent), 3.0 per cent (0.0 per cent-12.4 per cent) and 2.8 per cent (0.8 per cent-7.1 per cent), respectively. The frequency of detection of categories of postmortem diagnoses in fetuses, perinates, lambs and adults are presented. CONCLUSIONS: Comparisons with existing passive surveillance findings reflect some differences in the relative frequency of detection of certain categories of disease suggesting that sentinel flock surveillance could usefully supplement existing passive animal disease surveillance activities for ovine disease.

Analysis of trends in antimicrobial resistance in Neisseria gonorrhoeae isolated in Australia, 1997 2006.

OBJECTIVES: To analyse trends in antimicrobial resistance (AMR) in Neisseria gonorrhoeae (GC) isolated in Australia between 1997 and 2006 and to identify factors influencing emergence and spread of AMR in GC. METHODS: AMR data were generated in reference laboratories in each state and territory of Australia using the methods of the Australian Gonococcal Surveillance Programme from a comprehensive sample of GC. Trends in the proportion of strains resistant to penicillin, ciprofloxacin, spectinomycin and ceftriaxone or with high-level tetracycline resistance (TRNG) were determined from aggregated national data and were also disaggregated by region. Further analyses of additional AMR, demographic, transmission and antibiotic use data were also performed. RESULTS: More than 36,000 GC were examined. Significant increases in resistance to penicillin and ciprofloxacin and in TRNG occurred in national data and in urban populations. Approximately half of the GC tested in larger urban centres were penicillin and/or ciprofloxacin resistant by 2006. These high rates of resistance arose despite low (penicillin) or absent (ciprofloxacin) exposure. In contrast, in rural and remote areas with very high disease rates and high rates of penicillin use, <5% of GC tested were penicillin (or quinolone) resistant. No spectinomycin-resistant GC were detected. Low numbers of GC with raised MICs of ceftriaxone were present in urban centres each year from 2001 onwards. CONCLUSIONS: Significant increases in AMR in GC occurred in parts of Australia in the 10 years to 2006. The data suggest that the AMR seen in GC in urban populations were the result of their repeated importation into Australia and ultimate introduction into established sexual networks rather than originating de novo or as a result of selection by antibiotic use or misuse.

Creation of a competency-based professional development program for infection preventionists guided by the APIC Competency Model: steps in the process.

BACKGROUND: Infection Preventionists have varying levels of educational preparation. Many have no prior experience in IP. The diversity makes design of professional development programs challenging. Recent surveys suggest that only about half of practicing IPs are board certified. There is an urgent need to employ competent IP's to drive improvement in patient outcomes. METHODS: This is a project that utilized the APIC Competency Model to create a professional development program characterizing three career stages. Methods included a review of literature on professional development; a survey of IP competence; an assessment of job descriptions and performance evaluations; and a crosswalk of IP competencies. RESULTS: The professional development program includes competency - based IP job descriptions and performance evaluations for each career stage; a professional portfolio; and a toolkit for supervisors. DISCUSSION: Participants agreed that application of the model resulted in tools which are more closely aligned with current roles for IPs; and increased satisfaction and motivation with the new program. CONCLUSION: Competent and knowledgeable IP's are crucial to optimizing efficacy of IPC programs. A professional development program has the potential to guide staff orientation, improve satisfaction and retention, improve patient outcomes and promote a positive trajectory in advancing practice.

Life-Saving Esophageal Intubation in Neonate With Undiagnosed Tracheal Agenesis: A Case Report.

A 3-day-old, 2.2-kg former 34-week premature infant with imperforate anus required loop ileostomy surgery. At delivery, the child had respiratory distress. Endotracheal intubation was "confirmed" by detection of exhaled carbon dioxide with a Pedi-Cap (Covidien, Dublin, Ireland) and subsequent chest x-ray. On arrival to the operating room, the pulse oximeter reading was 100% despite a large leak around the endotracheal tube and high-airway pressures. Packing the throat reduced the leak and increased the tidal volume. Intraoperative bronchospasm occurred during the surgery. On postoperative day 1, fiberoptic examination by an otolaryngologist revealed esophageal intubation and the absence of laryngeal opening. Subsequent computed tomography scan revealed Floyd type II tracheal agenesis. To our knowledge, this is the only case of tracheal agenesis diagnosed after a non-airway related procedure. We discussed how the diagnosis was missed.

Oral Vaccination of Free-Living Badgers (Meles meles) with Bacille Calmette Guérin (BCG) Vaccine Confers Protection against Tuberculosis.

A field trial was conducted to investigate the impact of oral vaccination of free-living badgers against natural-transmitted Mycobacterium bovis infection. For a period of three years badgers were captured over seven sweeps in three zones and assigned for oral vaccination with a lipid-encapsulated BCG vaccine (Liporale-BCG) or with placebo. Badgers enrolled in Zone A were administered placebo while all badgers enrolled in Zone C were vaccinated with BCG. Badgers enrolled in the middle area, Zone B, were randomly assigned 50:50 for treatment with vaccine or placebo. Treatment in each zone remained blinded until the end of the study period. The outcome of interest was incident cases of tuberculosis measured as time to seroconversion events using the BrockTB Stat-Pak lateral flow serology test, supplemented with post-mortem examination. Among the vaccinated badgers that seroconverted, the median time to seroconversion (413 days) was significantly longer (p = 0.04) when compared with non-vaccinated animals (230 days). Survival analysis (modelling time to seroconversion) revealed that there was a significant difference in the rate of seroconversion between vaccinated and non-vaccinated badgers in Zones A and C throughout the trial period (p = 0.015). For badgers enrolled during sweeps 1-2 the Vaccine Efficacy (VE) determined from hazard rate ratios was 36% (95% CI: -62%- 75%). For badgers enrolled in these zones during sweeps 3-6, the VE was 84% (95% CI: 29%- 97%). This indicated that VE increased with the level of vaccine coverage. Post-mortem examination of badgers at the end of the trial also revealed a significant difference in the proportion of animals presenting with M. bovis culture confirmed lesions in vaccinated Zone C (9%) compared with non-vaccinated Zone A (26%). These results demonstrate that oral BCG vaccination confers protection to badgers and could be used to reduce incident rates in tuberculosis-infected populations of badgers.

Discovery and characterization of orthosteric and allosteric muscarinic M2 acetylcholine receptor ligands by affinity selection-mass spectrometry.

Screening assays using target-based affinity selection coupled with high-sensitivity detection technologies to identify small-molecule hits from chemical libraries can provide a useful discovery approach that complements traditional assay systems. Affinity selection-mass spectrometry (AS-MS) is one such methodology that holds promise for providing selective and sensitive high-throughput screening platforms. Although AS-MS screening platforms have been used to discover small-molecule ligands of proteins from many target families, they have not yet been used routinely to screen integral membrane proteins. The authors present a proof-of-concept study using size exclusion chromatography coupled to AS-MS to perform a primary screen for small-molecule ligands of the purified muscarinic M2 acetylcholine receptor, a G-protein-coupled receptor. AS-MS is used to characterize the binding mechanisms of 2 newly discovered ligands. NGD-3350 is a novel M2-specific orthosteric antagonist of M2 function. NGD-3366 is an allosteric ligand with binding properties similar to the allosteric antagonist W-84, which decreases the dissociation rate of N-methyl-scopolamine from the M2 receptor. Binding properties of the ligands discerned from AS-MS assays agree with those from in vitro biochemical assays. The authors conclude that when used with appropriate small-molecule libraries, AS-MS may provide a useful high-throughput assay system for the discovery and characterization of all classes of integral membrane protein ligands, including allosteric modulators.

Isolation of Vibrio cholerae O1 strains similar to pre-seventh pandemic El Tor strains during an outbreak of gastrointestinal disease in an island resort in Fiji.

Five strains of Vibrio cholerae O1, one each from an Australian and a New Zealand tourist with gastrointestinal illness returning from an island resort in Fiji and the remaining three from water sources located in the same resort, were extensively characterized. Conventional phenotypic traits that are used for biotyping of O1 V. cholerae categorized all five strains as belonging to the El Tor biotype. Genetic screening of 11 regions that are associated with virulence in V. cholerae showed variable results. The absence of genes comprising Vibrio seventh pandemic island-I (VSP-I) and VSP-II in all the strains indicated that these strains were very similar to the pre-seventh pandemic V. cholerae O1 El Tor strains. The ctxAB genes were absent in all strains whereas orfU and zot were present in four strains, indicating that the strains were non-toxigenic. Four strains carried a truncated CTX prophage. Although epidemiological and molecular studies suggested that these strains did not cause cholera amongst tourists at the resort, their similarity to pre-seventh pandemic strains, their prior association with gastrointestinal illness and their presence in the island resort setting warrant more attention.

Necessary Infrastructure of Infection Prevention and Healthcare Epidemiology Programs: A Review.

The scope of a healthcare institution's infection prevention and control/healthcare epidemiology program (IPC/HE) should be driven by the size and complexity of the patient population served, that population's risk for healthcare-associated infection (HAI), and local, state, and national regulatory and accreditation requirements. Essential activities of all IPC/HE programs include but are not limited to the following: ∙ Surveillance.∙ Performance improvement to reduce HAI ∙ Acute event response, including outbreak investigation ∙ Education and training of both healthcare personnel and patients ∙ Reporting of HAI to the Centers for Disease Control and Prevention's National Healthcare Safety Network as well as entities required by law.

Aboriginal and non-Aboriginal children in Western Australia carry different serotypes of pneumococci with different antimicrobial susceptibility profiles.

BACKGROUND: Carriage of Streptococcus pneumoniae is considered a precursor to pneumococcal diseases including pneumonia. As part of the Kalgoorlie Otitis Media Research Project, we characterised pneumococci isolated from the nasopharynx of Western Australian Aboriginal and non-Aboriginal children. METHODS: Between 1999 and 2005, 100 Aboriginal and 180 non-Aboriginal children were followed from birth to two years, with nasopharyngeal aspirates collected at ages 1-3 and 6-8 weeks, then at 4, 6, 12, 18 and 24 months. Introduction of 7-valent pneumococcal conjugate vaccine (7vPCV) in 2001 enabled evaluation of its impact on carriage in study participants according to vaccines doses received. Pneumococcal serotyping was performed by Quellung and antimicrobial susceptibility by disk diffusion and Etest®. Molecular epidemiology of pneumococcal isolates was investigated by pulse-field gel electrophoresis and multilocus sequence typing. RESULTS: Overall, the prevalence of 7vPCV serotypes was similar for Aboriginal and non-Aboriginal children (19 % vs. 16 %), but the prevalence of non-vaccine serotypes was higher in Aboriginal children (22 % vs. 7 %). A multi-resistant 6B clone (ST90) was found only in non-Aboriginal children. Aboriginal children who received three doses of 7vPCV had lower odds of carrying 7vPCV serotypes (odds ratio [OR] 0.19, 95 % CI 0.08-0.44) and higher odds of carrying non-vaccine serotypes (OR 2.37, 95 % CI 1.13-4.99) than unvaccinated Aboriginal children; this finding was not observed in non-Aboriginal children. CONCLUSIONS: This unique study shows important differences in pneumococcal serotypes, genotypes, and antimicrobial susceptibility between Aboriginal and non-Aboriginal children living in the same geographic area before widespread 7vPCV use, and highlights the need for ongoing post-vaccination surveillance in outback Australia.