Explore the vast range of titles available.

The MORDOR I trial 1 , conducted in Niger, Malawi and Tanzania, demonstrated that mass azithromycin distribution to preschool children reduced childhood mortality 1 . However, the large but simple trial design precluded determination of the mechanisms involved. Here we examined the gut microbiome of preschool children from 30 Nigerien communities randomized to either biannual azithromycin or placebo. Gut microbiome γ-diversity was not significantly altered ( P  = 0.08), but the relative abundances of two Campylobacter species, along with another 33 gut bacteria, were significantly reduced in children treated with azithromycin at the 24-month follow-up. Metagenomic analysis revealed functional differences in gut bacteria between treatment groups. Resistome analysis showed an increase in macrolide resistance gene expression in gut microbiota in communities treated with azithromycin ( P  = 0.004). These results suggest that prolonged mass azithromycin distribution to reduce childhood mortality reduces certain gut bacteria, including known pathogens, while selecting for antibiotic resistance. Mass antibiotic administration to preschool children in Nigerien communities alters the relative abundances of 35 bacterial species in the gut microbiome, including enteric pathogens, but also increases expression of macrolide resistance genes.

Campylobacteriosis and antimicrobial resistance (AMR) are global public health concerns. Africa is estimated to have the world's highest incidence of campylobacteriosis and a relatively high prevalence of AMR in Campylobacter spp. from humans and animals. Few studies have compared Campylobacter spp. isolated from humans and poultry in Africa using whole-genome sequencing and antimicrobial susceptibility testing. We explored the population structure and AMR of 178 Campylobacter isolates from East Africa, 81 from patients with diarrhea in Kenya and 97 from 56 poultry samples in Tanzania, collected during 2006-2017. Sequence type diversity was high in both poultry and human isolates, with some sequence types in common. The estimated prevalence of multidrug resistance, defined as resistance to >3 antimicrobial classes, was higher in poultry isolates (40.9%, 95% credible interval 23.6%-59.4%) than in human isolates (2.5%, 95% credible interval 0.3%-6.8%), underlining the importance of antimicrobial stewardship in livestock systems.

Background. Campylobacter species cause a high proportion of bacterial gastroenteritis cases and are a significant burden on health care systems and economies worldwide; however, the relative contributions of the various possible sources of infection in humans are unclear. Methods. National-scale genotyping of Campylobacter species was used to quantify the relative importance of various possible sources of human infection. Multilocus sequence types were determined for 5674 isolates obtained from cases of human campylobacteriosis in Scotland from July 2005 through September 2006 and from 999 Campylobacter species isolates from 3417 contemporaneous samples from potential human infection sources. These data were supplemented with 2420 sequence types from other studies, representing isolates from a variety of sources. The clinical isolates were attributed to possible sources on the basis of their sequence types with use of 2 population genetic models, STRUCTURE and an asymmetric island model. Results. The STRUCTURE and the asymmetric island models attributed most clinical isolates to chicken meat (58% and 78% of Campylobacter jejuni and 40% and 56% of Campylobacter coli isolates, respectively), identifying it as the principal source of Campylobacter infection in humans. Both models attributed the majority of the remaining isolates to ruminant sources, with relatively few isolates attributed to wild bird, environment, swine, and turkey sources. Conclusions. National-scale genotyping was a practical and efficient methodology for the quantification of the contributions of different sources to human Campylobacter infection. Combined with the knowledge that retail chicken is routinely contaminated with Campylobacter, these results are consistent with the view that the largest reductions in human campylobacteriosis in industrialized countries will come from interventions that focus on the poultry industry.

Campylobacter spp. is a major cause of foodborne diseases in humans, particularly when transmitted by the handling or consumption of undercooked poultry meat. Most Campylobacter infections are self-limiting, but antimicrobial treatment ( e.g ., fluoroquinolones and macrolides) is necessary in severe or prolonged cases. The indiscriminate use of these drugs, both in clinical medicine and animal production, has a major impact on public health. The aim of the present study was to identify Campylobacter strains, isolated from turkey and broilers, using both PCR and the matrix-assisted laser desorption–ionization time-of-flight (MALDI-TOF) methods to reveal the accuracy of identification, as well to evaluate the antimicrobial and genetic resistance of the investigated strains. MALDI-TOF and PCR methods were used to show differences, if any, in the specificity of that test. In this study, MALDI-TOF mass spectrometry gave the same results as multiplex PCR, in all cases. The highest rate of resistance ( i.e ., 100% of turkey and broiler strains) was detected against ciprofloxacin, whereas 58.1% of turkey and 78.6% of broiler strains were resistant to tetracycline. Multidrug-resistant isolates were not found in the study. All ciprofloxacin-resistant strains had a mutation in the gyrA gene, at the Thr-86 position. The presence of the tetO gene was found in 71% of turkey and in 100% of broiler strains. All resistant to tetracycline strains included tetO gene. Additionally, in five turkey and three broiler strains, susceptible to tetracycline, tetO gene was present. These results indicate the high prevalence of Campylobacter strains, which are phenotypically and genetically resistant to fluoroquinolones and tetracycline.

Campylobacter spp. are leading bacterial gastroenteritis pathogens. Infections are largely underreported, and the burden of outbreaks may be underestimated. Current strategies of testing as few as one isolate per sample can affect attribution of cases to epidemiologically important sources with high Campylobacter diversity, such as chicken meat. Multiple culture method combinations were utilized to recover and sequence Campylobacter from 45 retail chicken samples purchased across Norwich, UK, selecting up to 48 isolates per sample. Simulations based on resampling were used to assess the impact of Campylobacter sequence type (ST) diversity on outbreak detection. Campylobacter was recovered from 39 samples (87%), although only one sample was positive through all broth, temperature, and plate combinations. Three species were identified (Campylobacter jejuni, Campylobacter coli, and Campylobacter lari), and 33% of samples contained two species. Positive samples contained 1–8 STs. Simulation revealed that up to 87 isolates per sample would be required to detect 95% of the observed ST diversity, and 26 isolates would be required for the average probability of detecting a random theoretical outbreak ST to reach 95%. An optimized culture approach and selecting multiple isolates per sample are essential for more complete Campylobacter recovery to support outbreak investigation and source attribution.

Background Campylobacteriosis is a dominant bacterial cause of foodborne infection and is considered the main public health problem in Europe and many other countries worldwide. In the study lasting from 2011 to 2013 we compared the prevalence and antimicrobial resistance of Campylobacter jejuni and Campylobacter coli isolated from children, domestic animals, poultry meat and surface water in Northern Poland. Results During a 3-years study 1973 samples were analysed. The results proved the presence of Campylobacter spp. in 306 (15.5%) samples. The percentage of Campylobacter -positive samples differed among the sample types, from 0% (freshwater beaches) to 38.6% (poultry meat in 2011). Prevalence of Campylobacter spp. in children isolates was 9.6%. It decreased from 13.2% in 2011 to 8.0% in 2013. It should be highlighted with a particular concern that Campylobacter jejuni was detected in 20.0% of fountains. All children and poultry meat isolates were susceptible to azithromycin. Two C. coli (3.7%) and four C. jejuni (3.3%) isolated from poultry meat were resistant to erythromycin. The highest percentage of C. jejuni isolates with resistance to ciprofloxacin were found in samples from 80% dogs and 85% ponds. Among isolates resistant to two antimicrobials 74.7% C. jejuni and 59.2% C. coli isolates were resistant to ciprofloxacin as well as to tetracycline. Only one cat C. coli isolate was resistant to both azithromycin and erythromycin. One C. jejuni isolate from a fountain was resistant to four antimicrobial agents (erythromycin, azithromycin, tetracycline and ciprofloxacin). Conclusions The study proved that surface water, poultry meat and pets constituted potential sources of Campylobacter to children. Fountains can be a direct source of children campylobacteriosis but can also pollute other environments with multidrug-resistant Campylobacter . The high resistance to some antimicrobials among the isolates may lead to increasing numbers of difficult-to-treat campylobacteriosis cases among children.

Gastrointestinal disease is one of the most common reasons for hospitalization in non-human primate colonies and accounts for over one-third of non-research related euthanasia. In rhesus macaques, this manifests as both acute diarrhea and chronic enterocolitis (CE), a syndrome of chronic diarrhea resulting in poor weight gain or weight loss which is minimally responsive to treatment. Campylobacter spp. are major causes of acute enterocolitis in rhesus macaques and may predispose individuals to the development of CE, similar to post-infectious irritable bowel syndrome in humans. Despite these concerns, there are few studies characterizing Campylobacter in rhesus macaque colonies, in particular utilizing whole genome sequencing and assessing findings with respect to the health status of the host. Our findings provide insight into Campylobacter strains circulating in rhesus macaque colonies, which can improve clinical monitoring, assist in treatment decisions, and provide new avenues of investigation into campylobacteriosis as a catalyst for CE.

Background The clinical course of Campylobacter infection varies in symptoms and severity depending on host factors, virulence of the pathogen and initiated therapy. The type VI secretion system (T6SS) has been identified as a novel virulence factor, which mediates contact-dependent injection of enzymes and toxins into competing bacteria or host cells and facilitates the colonisation of a host organism. We aimed to compare the clinical course of Campylobacter infection caused by strains with and without the T6SS and identify possible associations between this putative virulence factor and the clinical manifestations of disease. Methods From April 2015 to January 2017, patients with detection of Campylobacter spp. were identified at the University Hospital of Basel and the University Children’s Hospital of Basel and included in this case-control study. Presence of the T6SS gene cluster was assayed by PCR targeting the hcp gene, confirmed with whole genome sequencing. Pertinent clinical data was collected by medical record review. Differences in disease- and host-characteristics between T6SS-positive (case) and –negative (control) were compared in a uni- and multi-variable analysis. Hospital admission, antibiotic therapy, admission to intensive care unit, development of bacteraemia and in-hospital mortality were considered as clinical endpoints. Results We identified 138 cases of Campylobacter jejuni infections and 18 cases of Campylobacter coli infections from a paediatric and adult population. Analyses were focused on adult patients with C. jejuni ( n  = 119) of which 16.8% were T6SS-positive. Comparisons between T6SS-positive and -negative C. jejuni isolates did not reveal significant differences regarding clinical manifestations or course of disease. All clinical endpoints showed a similar distribution in both groups. A higher score in the Charlson Comorbidity Index was associated with T6SS-positive C. jejuni isolates ( p  < 0.001) and patients were more likely to have a solid organ transplant and to be under immunosuppressive therapy. Conclusions Our study does not provide evidence that T6SS is associated with a more severe clinical course. Interestingly, T6SS-positive isolates are more commonly found in immunocompromised patients: an observation which merits further investigation.

Background Freshwater is a major source of human waterborne infections caused by Campylobacter species. The extensive use of antibiotics is capable of causing the emergence and spread of Campylobacter strains that are resistant to the antibiotics, making campylobacteriosis more difficult to treat and persistent in the environment. This study evaluated the occurrence and antimicrobial resistance profiles of Campylobacter species in freshwater from the Eastern Cape Province, South Africa. Materials and methods Sixty-one freshwater samples were collected, yielding 302 presumptive Campylobacter isolates. PCR assays confirmed 78 isolates as belonging to Campylobacter species, identifying 35 (45%) as C. jejuni , 29 (37%) as C. coli , and 14 (18%) as C. lari . Antibiotic susceptibility testing was conducted to determine resistance patterns. Results The isolates showed high resistance to erythromycin (90%) and low resistance to gentamicin (11.58%). The most frequently observed resistance pattern was C-LEV-NA-AZM-CIP-AMP-IMI-GM-DO-S-TE-E for C. lari , C-LEV-NA-AZM-CIP-AMP-GM-DO-S-TE-E for C. jejuni , and C-LEV-NA-AZM-CIP-AMPI-GM-DO-TE-E for C. coli. (Chloramphenicol, Levofloxacin, Nalidixic acid, Azithromycin, Ciprofloxacin, Ampicillin, Imipenem, Gentamicin, Doxycycline, Streptomycin, Tetracycline, and Erythromycin). Most isolates had multiple antibiotic resistance (MAR) indices greater than 0.2. Genetic analysis revealed imipenem resistance genes ( bla IMP ) in 85.71% of isolates, followed by bla VIM (71.43%). The ermA gene was detected in only 4% of cases. The isolates tested negative for bla KPC , bla GES , ermC , and qnrA resistance genes. Conclusion The study shows that antimicrobial-resistant and potentially virulent Campylobacter strains are present in the freshwater environments in the Eastern Cape Province, posing a potential public health risk. However, surveillance systems and public awareness about campylobacteriosis and its transmission routes can reduce infection rates.

The increasing resistance of bacteria to antimicrobials is a major threat to public health. This study investigates the prevalence of antimicrobial resistance, both phenotypic and genotypic, among Campylobacter isolates from Australian meat chickens in 2022, as a follow up to investigate trends since the last national surveillance undertaken in 2016. Isolates ( n  = 186) were obtained at slaughter from 200 pooled cecal samples taken from 1,000 meat chickens. The majority of C. jejuni (68.7%) and C. coli (88.9%) isolates were susceptible to all the antibiotics that were tested, and no multi-drug resistance was found. Resistance to ciprofloxacin (fluoroquinolone) was detected in 24.4% of the C. jejuni and 3.2% of the C. coli isolates. Whole genome sequencing revealed a diverse range of sequence types (STs). These included 32 previously reported STs for C. jejuni and 13 for C. coli , as well as four and seven previously undescribed STs for each species, respectively. The STs containing fluoroquinolone-resistant isolates were ST2083, ST10130, ST2895, ST7323, ST2398, and ST1078 for C. jejuni , and ST860 and ST894 for C. coli . Although fluoroquinolones are not used in animal production in Australia, resistance amongst C. jejuni isolates was high (24.4%). This finding emphasizes the need for enhanced surveillance and regular sampling along the food chain to understand the source of the isolates and to mitigate risks of antimicrobial resistance to protect public health.