Campylobacter jejuni is the leading cause of bacterial gastroenteritis globally, and infections are often transmitted through consumption of raw or undercooked poultry.Campylobacter jejuni ST50 is among the top ten sequence types (STs) reported in the collected isolates listed at PubMLST records from poultry, food and clinical sources for Asia, Europe, North America, Oceania and South America. This study was designed to determine the most commonly reported C. jejuni STs globally using the PubMLST database and assess similarities between genomes of C. jejuni ST50 isolates from geographically distinct locations. To gain a better understanding of C. jejuni diversity, we compared draft genome sequences of 182 ST50 isolates recovered from retail or caecal poultry samples in Oceania, Europe and North America that were collected over a period of 9 years (2010 to 2018). Overall, phylogenetic analysis revealed that isolates from geographically distinct locations tended to cluster based on the continent where the sample was collected. Among ST50 isolates from Europe and North America, we identified resistance determinants associated with phenotypic resistance to beta-lactams (EU: 55%; GB: 43.1%), tetracyclines (CA: 77.3%; EU: 37.5%; GB: 9.8%; US: 43.5%) and fluoroquinolones (EU: 60.0%; GB: 15.7%); no resistance determinants were identified in isolates from Australia. In general, the majority of the virulence genes, with rare exceptions such as wlaN, cj1138, hddA and rfbC, were evenly distributed throughout the genomes of all ST50 isolates in this study.Genomic-based characterization of C. jejuni ST50 isolates from poultry on three continents highlighted that geographically distinct isolates have evolved independently but only represent a glimpse into the diversity of C. jejuni.

BackgroundSchistosomiasis is a widespread public health concern in the poorest regions of the world. The principal control strategy is regular praziquantel administration to school-aged children in endemic areas. With calls for the elimination of schistosomiasis as a public health problem, expanding praziquantel delivery to all community members has been advocated. This systematic review and meta-analysis compares the impact of community-wide and child-targeted praziquantel distribution on schistosomiasis prevalence and intensity in school-aged children.Methodology/Principal findingsWe searched MEDLINE, Embase and Web of Science to identify papers that reported schistosome prevalence before and after praziquantel administration, either to children only or to all community members. Extracted data included Schistosoma species, drug administration strategy, number of treatment rounds, follow-up interval and prevalence and intensity before and after treatment. We used inverse variance weighted generalised linear models to examine the impact of mass versus targeted drug administration on prevalence reduction, and weighted boxplots to examine the impact on infection intensity reduction. This study is registered with PROSPERO, number CRD42018095377.In total, 34 articles were eligible for systematic review and 28 for meta-analysis. Schistosoma mansoni was reported in 20 studies; Schistosoma haematobium in 19 studies, and Schistosoma japonicum in two studies. Results of generalised linear models showed no detectable difference between mass and targeted treatment strategies on prevalence reduction in school-aged children for S. mansoni (odds ratio 0.47, 95%CI 0.13–1.68, p = 0.227) and S. haematobium (0.41, 95%CI 0.06–3.03, p = 0.358). Box plots also showed no apparent differences in intensity reduction between the two treatment strategies.Conclusions/SignificanceThe results of this meta-analysis do not support the hypothesis that community-wide treatment is more effective than targeted treatment at reducing schistosomiasis infections in children. This may be due to the relatively small number of included studies, insufficient treatment coverage, persistent infection hotspots and unmeasured confounders. Further field-based studies comparing mass and targeted treatment are required.

Background We aimed to identify risk factors for sporadic campylobacteriosis in Australia, and to compare these for Campylobacter jejuni and Campylobacter coli infections. Methods In a multi-jurisdictional case-control study, we recruited culture-confirmed cases of campylobacteriosis reported to state and territory health departments from February 2018 through October 2019. We recruited controls from notified influenza cases in the previous 12 months that were frequency matched to cases by age group, sex, and location. Campylobacter isolates were confirmed to species level by public health laboratories using molecular methods. We conducted backward stepwise multivariable logistic regression to identify significant risk factors. Results We recruited 571 cases of campylobacteriosis (422 C. jejuni and 84 C. coli) and 586 controls. Important risk factors for campylobacteriosis included eating undercooked chicken (adjusted odds ratio [aOR] 70, 95% CI 13–1296) or cooked chicken (aOR 1.7, 95% CI 1.1–2.8), owning a pet dog aged < 6 months (aOR 6.4, 95% CI 3.4–12), and the regular use of proton-pump inhibitors in the four weeks prior to illness (aOR 2.8, 95% CI 1.9–4.3). Risk factors remained similar when analysed specifically for C. jejuni infection. Unique risks for C. coli infection included eating chicken pâté (aOR 6.1, 95% CI 1.5–25) and delicatessen meats (aOR 1.8, 95% CI 1.0–3.3). Eating any chicken carried a high population attributable fraction for campylobacteriosis of 42% (95% CI 13–68), while the attributable fraction for proton-pump inhibitors was 13% (95% CI 8.3–18) and owning a pet dog aged < 6 months was 9.6% (95% CI 6.5–13). The population attributable fractions for these variables were similar when analysed by campylobacter species. Eating delicatessen meats was attributed to 31% (95% CI 0.0–54) of cases for C. coli and eating chicken pâté was attributed to 6.0% (95% CI 0.0–11). Conclusions The main risk factor for campylobacteriosis in Australia is consumption of chicken meat. However, contact with young pet dogs may also be an important source of infection. Proton-pump inhibitors are likely to increase vulnerability to infection.

Background We aimed to identify risk factors for sporadic campylobacteriosis in Australia, and to compare these for Campylobacter jejuni and Campylobacter coli infections. Methods In a multi-jurisdictional case–control study, we recruited culture-confirmed cases of campylobacteriosis reported to state and territory health departments from February 2018 through October 2019. We recruited controls from notified influenza cases in the previous 12 months that were frequency matched to cases by age group, sex, and location. Campylobacter isolates were confirmed to species level by public health laboratories using molecular methods. We conducted backward stepwise multivariable logistic regression to identify significant risk factors. Results We recruited 571 cases of campylobacteriosis (422 C. jejuni and 84 C. coli) and 586 controls. Important risk factors for campylobacteriosis included eating undercooked chicken (adjusted odds ratio [aOR] 70, 95% CI 13–1296) or cooked chicken (aOR 1.7, 95% CI 1.1–2.8), owning a pet dog aged < 6 months (aOR 6.4, 95% CI 3.4–12), and the regular use of proton-pump inhibitors in the 4 weeks prior to illness (aOR 2.8, 95% CI 1.9–4.3). Risk factors remained similar when analysed specifically for C. jejuni infection. Unique risks for C. coli infection included eating chicken pâté (aOR 6.1, 95% CI 1.5–25) and delicatessen meats (aOR 1.8, 95% CI 1.0–3.3). Eating any chicken carried a high population attributable fraction for campylobacteriosis of 42% (95% CI 13–68), while the attributable fraction for proton-pump inhibitors was 13% (95% CI 8.3–18) and owning a pet dog aged < 6 months was 9.6% (95% CI 6.5–13). The population attributable fractions for these variables were similar when analysed by campylobacter species. Eating delicatessen meats was attributed to 31% (95% CI 0.0–54) of cases for C. coli and eating chicken pâté was attributed to 6.0% (95% CI 0.0–11). Conclusions The main risk factor for campylobacteriosis in Australia is consumption of chicken meat. However, contact with young pet dogs may also be an important source of infection. Proton-pump inhibitors are likely to increase vulnerability to infection.

Campylobacter jejuni and Campylobacter coli infections are the leading cause of foodborne gastroenteritis in high‐income countries. Campylobacter colonizes a variety of warm‐blooded hosts that are reservoirs for human campylobacteriosis. The proportions of Australian cases attributable to different animal reservoirs are unknown but can be estimated by comparing the frequency of different sequence types in cases and reservoirs. Campylobacter isolates were obtained from notified human cases and raw meat and offal from the major livestock in Australia between 2017 and 2019. Isolates were typed using multi‐locus sequence genotyping. We used Bayesian source attribution models including the asymmetric island model, the modified Hald model, and their generalizations. Some models included an “unsampled” source to estimate the proportion of cases attributable to wild, feral, or domestic animal reservoirs not sampled in our study. Model fits were compared using the Watanabe–Akaike information criterion. We included 612 food and 710 human case isolates. The best fitting models attributed >80% of Campylobacter cases to chickens, with a greater proportion of C. coli (>84%) than C. jejuni (>77%). The best fitting model that included an unsampled source attributed 14% (95% credible interval [CrI]: 0.3%–32%) to the unsampled source and only 2% to ruminants (95% CrI: 0.3%–12%) and 2% to pigs (95% CrI: 0.2%–11%) The best fitting model that did not include an unsampled source attributed 12% to ruminants (95% CrI: 1.3%–33%) and 6% to pigs (95% CrI: 1.1%–19%). Chickens were the leading source of human Campylobacter infections in Australia in 2017–2019 and should remain the focus of interventions to reduce burden.