Prevalence, antimicrobial resistance, virulence gene profile and molecular typing of Campylobacter species isolated from poultry meat samples

Campylobacter in Raw Chicken Meat at Retail Level: Quantitative and Qualitative Assessment, Genomic Profiling, and Comparison With Isolates From Human Infections

Campylobacter is the leading cause of human bacterial diarrheal disease, and the handling and consumption of poultry meat products account for most cases. This cross-sectional study aimed to determine the prevalence and levels of Campylobacter in Swiss and imported retail chicken meat during May - August 2024. Whole-genome sequencing (WGS) was applied to assess phylogenetic relatedness between Campylobacter from chicken meat samples and human infections occurring during the study time in Switzerland, and to identify antimicrobial resistance and virulence genes. A total of 300 different chilled or frozen chicken meat samples and 50 chilled marinated meat samples were analyzed by qualitative (enrichment) and quantitative (plating) ISO 10272-1:2017 and ISO 10272-2:2017 methods. After enrichment, the Campylobacter recovery rate was higher in chilled (62%) than in marinated meat (40%) or frozen chicken meat (11%). Campylobacter were more prevalent in meat from organically labeled meat (72%) and free-range labeled meat (77%) compared to meat with other labels. Quantitatively, 3.7% of chilled, nonmarinated meat had >100 colony-forming units (cfu)/g (range 100-700 cfu/g). The detection of multiple genetically indistinguishable isolates from meat and from humans indicated that chilled chicken meat is a major infection source for Swiss cases of campylobacteriosis. Antimicrobial resistance determinants included blaOXA, tet(O), and the T86I substitution in GyrA. Virulence genes cstIII, neuABC, wlaN, and cdtABC which are linked to the Guillain-Barré syndrome and gastrointestinal cancers, respectively, were identified. Our data highlight the need to reduce the levels of Campylobacter in chicken meat to protect public health. Freezing meat prior to retailing is an effective and relatively inexpensive measure to increase product safety and to reduce the risk of campylobacteriosis in humans.

Towards an inclusive conference experience: evaluation of the Education and Outreach Symposium at the Microbiology Society Annual Conference 2024

The Microbiology Society Education and Outreach Symposium serves as a platform for microbiology educators to share contemporary practices with an international audience. The Symposium is held yearly during the Microbiology Society's Annual Conference and has become increasingly popular among conference attendees. In an effort to create an inclusive and engaging environment, the 2024 Symposium included contributions from participants at all career stages and from diverse global regions through a variety of presentation formats, including invited talks, offered presentations, flash talks and posters. Cabaret-style seating was used to encourage discussion amongst participants, and digital tools were used for anonymous feedback and questions after each talk to ensure all voices had an opportunity to be heard. Here, we present an analysis of qualitative and quantitative participant responses addressing two key research questions: (1) Did the Symposium foster an inclusive atmosphere for participants across all career stages? and (2) Was the content engaging and relevant to the audience? A post-Symposium questionnaire revealed strong positive feedback, with all 18 respondents agreeing or strongly agreeing that the 2024 Symposium was both an inclusive environment and covered interesting topics. Thematic content analysis of free-text responses emphasized a high appreciation for the Symposium's diversity in speakers and topics, an inclusive room layout and an overall welcoming feeling. Feedback from participants, along with the authors' own reflections, will actively feed into planning for the 2025 Symposium.

Comparative Molecular Virulence Typing and Antibiotic Resistance of Campylobacter Species at the Human-Animal-Environment Interface

This study holds significant importance due to its focus on Campylobacter, the leading bacterial cause of gastroenteritis worldwide, responsible for ∼96 million cases each year. By investigating the prevalence of both Campylobacter jejuni and Campylobacter coli in humans, animals, and the environment, this research sheds light on the broader impact of these pathogens, which can harm both human and animal populations. Traditional microbiological methods were implemented followed by optimized multiplex polymerase chain reaction targeting 16S rDNA and virulence gene markers by using specific primers. The findings revealed that a total of 219 Campylobacter isolates were recovered from 528 collected specimens from human, animal, and environmental sources. Campylobacter species showed a prevalence of 41.5%, with C. jejuni accounting for 53% and C. coli for 47%. Antimicrobial resistance rates were high, with tetracycline at 89%, ceftriaxone at 75%, cefotaxime at 70%, erythromycin at 69%, nalidixic acid at 54%, ciprofloxacin at 39%, and gentamicin at 23%. Commonly prevalent virulence-associated genes observed in the Campylobacter were cadF at 93%, flaA at 91%, cdtB at 88%, cheY at 86%, sodB at 78%, and iamA at 32%. The study confirmed multidrug-resistant Campylobacter prevalence at the human-animal-environment interface, harboring virulence-associated genes with potential harm to humans. Data analysis showed a nonsignificant (p ≥ 0.05) correlation between virulence genes and antibiotic susceptibility. To effectively manage Campylobacter infections, a multifaceted strategy incorporating preventative interventions at different levels is required. This strategy should take into account practicability, effectiveness, and sustainability while strengthening surveillance systems and addressing the economics of disease prevention.

Genetic characteristics, antimicrobial susceptibility, and virulence genes distribution of Campylobacter isolated from local dual-purpose chickens in central China

Food-borne antibiotic-resistant Campylobacter poses a serious threat to public health. To understand the prevalence and genetic characteristics of Campylobacter in Chinese local dual-purpose (meat and eggs) chickens, the genomes of 30 Campylobacter isolates, including 13 C. jejuni and 17 C. coli from Jianghan-chickens in central China, were sequenced and tested for antibiotic susceptibility. The results showed that CC-354 and CC-828 were the dominant clonal complexes of C. jejuni and C. coli, respectively, and a phylogenetic analysis showed that three unclassified multilocus sequence types of C. coli were more closely genetically related to C. jejuni than to other C. coli in this study. Of the six antibiotics tested, the highest resistance rates were to ciprofloxacin and tetracycline (100%), followed by lincomycin (63.3%), erythromycin (30.0%), amikacin (26.7%), and cefotaxime (20.0%). The antibiotic resistance rate of C. coli was higher than that of C. jejuni. The GyrA T86I mutation and 15 acquired resistance genes were detected with whole-genome sequencing (WGS). Among those, the GyrA T86I mutation and tet(O) were most prevalent (both 96.7%), followed by the blaOXA-type gene (90.0%), ant(6)-Ia (26.7%), aac(6')-aph(3'') (23.3%), erm(B) (13.3%), and other genes (3.3%). The ciprofloxacin and tetracycline resistance phenotypes correlated strongly with the GyrA T86I mutation and tet(O)/tet(L), respectively, but for other antibiotics, the correlation between genes and resistance phenotypes were weak, indicating that there may be resistance mechanisms other than the resistance genes detected in this study. Virulence gene analysis showed that several genes related to adhesion, colonization, and invasion (including cadF, porA, ciaB, and jlpA) and cytolethal distending toxin (cdtABC) were only present in C. jejuni. Overall, this study extends our knowledge of the epidemiology and antibiotic resistance of Campylobacter in local Chinese dual-purpose chickens.

Antibiotic Resistance in Campylobacter: A Systematic Review of South American Isolates

In recent years, Campylobacter has become increasingly resistant to antibiotics, especially those first-choice drugs used to treat campylobacteriosis. Studies in South America have reported cases of antibiotic-resistant Campylobacter in several countries, mainly in Brazil. To understand the current frequency of antibiotic-resistant Campylobacter in humans, farm animals, and food of animal origin in South America, we systematically searched for different studies that have reported Campylobacter resistance. The most commonly reported species were C. jejuni and C. coli. Resistance to ciprofloxacin was found to be ubiquitous in the isolates. Nalidixic acid and tetracycline showed a significantly expressed resistance. Erythromycin, the antibiotic of first choice for the treatment of campylobacteriosis, showed a low rate of resistance in isolates but was detected in almost all countries. The main sources of antibiotic-resistant Campylobacter isolates were food of animal origin and farm animals. The results demonstrate that resistant Campylobacter isolates are disseminated from multiple sources linked to animal production in South America. The level of resistance that was identified may compromise the treatment of campylobacteriosis in human and animal populations. In this way, we are here showing all South American communities the need for the constant surveillance of Campylobacter resistance and the need for the strategic use of antibiotics in animal production. These actions are likely to decrease future difficulties in the treatment of human campylobacteriosis.