Investigating potential zoonotic viruses in animal reservoirs is crucial to anticipate viral emergence. Seals can represent large populations of coastal mammals with unknown consequences on the microbiological quality of their surrounding environment. To assess this, we conducted a metaviromics analysis of feces collected from two species of seals in the North-Western Atlantic (Saint-Pierre et Miquelon archipelago). We focused on the Caliciviridae family, which regroups several genera with viruses infecting humans and other mammals, including marine mammals, but none identified in seals (Phocidae). Among the assembled sequences identified as Caliciviridae, there were four known genera (norovirus, sapovirus, vesivirus, and salovirus) and unknown, distantly related viruses. Complete or nearly-complete genomes could be assembled for each genus. Norovirus and sapovirus sequences from seals were diverse and likely represent several new genogroups or genotypes. Seal vesivirus formed a monophyletic group, representing a potential new species related to the canine vesivirus. Salovirus, which are fish viruses, were likely diet-derived, like the distant sequences which exhibited the hallmarks of caliciviruses and were more closely related to fish and reptile viruses. In conclusion, seals are a reservoir for a large diversity of Caliciviridae, some related to norovirus or sapovirus genotypes known to infect humans, and their impact on the quality of coastal water or shellfish should be further assessed. This study expands the knowledge on Caliciviridae genetic diversity and circulation in marine mammals.

This document presents the opinion of the French Agency for Food, Environmental and Occupational Health & Safety (ANSES), established from the work of its Working Group on “Risks associated with the consumption of Nitrites and Nitrates" (NiNa WG) and validated by its Expert Committees on “Assessment of the biological risks in foods” (CES BIORISK) and “Assessment of physico-chemical risks in food” (CES ERCA). Following a request from the Directorate General for Health, the Directorate General for Food and the Directorate General for Competition, Consumer Affairs and Fraud Control, ANSES was asked to deliver an opinion on the risks linked to nitrites and nitrates. Specifically, ANSES provided a scientific assessment associated with the following work themes regarding questions of (i) the impact of reducing nitrite/nitrate levels in foodstuffs on the fate of pathogenic bacteria in certain foods, (ii) the assessment of overall exposure to nitrates and nitrites from all sources in France and the proposal of actions that could help reduce this exposure, (iii) evaluating if new scientific knowledge could justify revisiting EFSA's ADIs/Health-Based Guidance Values (HBGVs) for nitrates and nitrites, and (iv) better characterizing their link to human cancer risk from meat product consumption. The opinion first presents the substances of interest, their origin and the regulatory framework. Then this opinion sets out the conclusions of the microbiological risk for three foodborne pathogens associated with reducing nitrate/nitrite levels as additives in three types of cured meats. This is followed by a presentation of the conclusions relating to the assessment of the available epidemiological and toxicological data in the light of recent scientific data. Finally, this enables the characterization of the risk associated with ingested nitrates and nitrites after exposure has been estimated. The opinion provides recommendations to continue epidemiological studies to confirm or refute suspected relationships for certain cancers and to conduct experimental studies for the establishment of ADIs considering the combined exposure to nitrates, nitrites and nitroso compounds. Furthermore, reducing the population's exposure to nitrites and nitrates involves collective and individual measures. As part of collective measures, in addition to controlling the quality of water intended for human consumption, a relevant measure would be to reduce the use of nitrites in processed meat products while implementing strict compensatory measures to address microbiological risk. This opinion finally emphasizes the importance of individual measures, by adhering to recommendations for processed meat consumption, limiting it to 150g/week, and diversifying the consumption of fruits and vegetables.

This document presents the opinion of the French Agency for Food, Environmental and Occupational Health & Safety (ANSES), established from the work of its BIORISK Expert Committee. Two questions were presented to ANSES by the French Directorate General for Food, relating to the establishment of a risk profile for Toxocara spp. in wild boar meat and the proposal of control measures for risk management. An expert appraisal was requested in light of the recent discovery of Toxocara spp. larvae in inspected wild boar carcasses in France. The document begins by describing the parasite cycle, modes of transmission, and clinical forms of toxocariasis in humans. The discussion particularly focuses on the relative importance of foodborne transmission in comparison to other transmission methods. The wild boar meat-processing sector is also described. In addition, there is an assessment of various methods for inactivating Toxocara spp. in meats, including freezing, cooking, and curing. The opinion draws conclusions from the risk profile for the continuation of work on toxocariasis on one hand, and the assessment of microbiological risks for wild boar meat on the other. Control measures that may be effective against Toxocara spp. are also presented. A series of recommendations aimed at various stakeholders (processing facilities, hunters, and consumers) is provided by the document.

ABSTRACT Shiga toxin‐producing Escherichia coli (STEC) are pathogenic E. coli strains that have been associated with a wide range of human clinical illness ranging from mild diarrhoea to bloody diarrhoea (BD) and haemolytic uremic syndrome (HUS). In its opinion of 18 May 2017, the French Agency for Food, Environmental and Occupational Health and Safety (ANSES) defined the pathogenic STEC strains according to genetic criteria (presence of stx1 and/or stx2, eae or (aaiC and aggR) genes) and serotyping. The list of high risk strains included those belonging to the following serotypes: O157:H7, O26:H11, O145:H28, O103:H2, O111:H8, O104:H4, O80:H2). In 2018, an FAO/WHO expert group proposed to classify STEC strains according to their potential risk of causing severe illness into five risk levels based on virulence gene combinations. In 2020, the EFSA BIOHAZ Panel concluded that all STEC strains are pathogenic to humans, capable of causing at least diarrhoea and that all STEC subtypes may be associated with severe illness. The French Directorate‐General for Food requested ANSES to review the definition of STEC pathogenic strains proposed in the May 2017 opinion in the light of the EFSA BIOHAZ Panel opinion, the FAO/WHO report and recent French and European epidemiological data. A literature review was conducted to collect scientific publications, reports and official documents published between 2017 and 2021. The following data were considered: French data on human cases (incidence, microbiological characteristics of the strains associated with human cases), data from the European surveillance system (ECDC TESSy database), data on the occurrence of STEC in foods. The classifications of STEC strains proposed by ANSES in 2017 and FAO/WHO in 2018 were compared with French microbiological and epidemiological surveillance data (2017‐2021), to assess their predictive potential. As the existing classifications were not fully consistent with the French surveillance data (2017‐2021), a new classification of STEC strains according to their virulence potential was proposed. This classification takes into account the association of strains with severe forms of infection (mainly HUS, followed by BD). The criterion used to rank and classify strains is the positive predictive value (PPV; i.e. the probability of the strain to cause illness) for HUS, then the PPV for BD in case of equivalence. STEC strains with the stx2a and/or stx2d subtypes have the highest potential to cause HUS, particularly in the presence of the eae adhesion gene (group I). eae‐negative strains with the stx2a and/or stx2d variants (group II) also have a high potential to cause HUS, especially in adults (22% of HUS cases in adults compared to 1% in children under 15 years of age). STEC strains with other subtypes of the stx gene (groups III and IV) are less frequently associated with HUS cases and are mainly found in cases of bloody diarrhoea and diarrhoea. Serogroup is no longer used to classify strains. However, serogroup information is still useful in human and food epidemiosurveillance. This classification can be used to define management measures (surveillance, management of contaminated batches) corresponding to the level of protection previously defined by risk managers.

IntroductionSeals, protected wild marine mammals, are widely found in waters around the world. However, rising concerns about their increasing numbers in some areas have led to potential worries regarding microbiological contamination of coastal areas by their feces, which could impact bathing and shellfish-harvesting activities. To the best of our knowledge, no study has been conducted on the bacterial and RNA viral communities present in the feces of both grey and harbor seals, which are the two main seal species observed in mainland France and overseas.MethodsFecal bacterial (n = 132) and RNA viral (n = 40) communities of seals were analyzed using 16S rRNA gene amplicon high-throughput sequencing and viral RNA sequencing methods, respectively. In addition, to identify the specific characteristics of seal fecal microbial communities compared to other animal fecal microbial communities that may also contaminate coastal areas, the bacterial communities of seals were compared to those of wild waterbirds and breeding animals (i.e., cattle and pigs) which could be present in upstream catchments of coastal areas. Finally, ANCOM was used to identify unique and seal-associated Amplicon Sequence Variants (ASVs), aiming to develop a Microbial Source Tracking (MST) bacterial qPCR marker associated with seals.Results and discussionThe bacterial communities of grey and harbor seals were not found to be significantly different and were characterized by a predominance of Firmicutes, including the genera Clostridium sensu stricto 1 and Peptoclostridium, followed by Fusobacteriota with the genus Fusobacterium, and Bacteroidota with the genus Bacteroides. However, variations in bacterial communities between sites and individuals were observed. Similar observations were made for the RNA viral communities being characterized by a predominance of Picobirnaviridae (44% of total reads) and Astroviridae (15%). This study successfully developed a sensitive (89.8%) and specific (97.1%) MST qPCR marker targeting grey seal-associated bacteria belonging to the Bifidobacteriaceae family. This marker can be used to identify potential fecal contamination of coastal areas by seals and complements the MST toolboxes of markers already developed for humans, wild birds and livestock.

This study evaluated the contribution of cattle, sheep, poultry and pigs to the contamination of surface water from rivers by Campylobacter jejuni and C. coli using MLST, cgMLST and considered MALDI-TOF MS as an alternative technique. The 263 strains isolated from cattle (n = 61), sheep (n = 42), poultry (n = 65), pigs (n = 60) and surface water (n = 35) were distributed across 115 sequence types (STs), 49 for C. jejuni and 66 for C. coli. Considering MLST data, 14.2%, 11.4% and 2.8% of the surface water strains could be attributed to cattle, poultry and sheep, respectively, none to pigs, and 85.7% were non-attributed. Analysis of cg-MLST data with STRUCTURE indicated that C. jejuni strains from water were predominantly attributed to poultry (93.5%), weakly to sheep (<1%) and 6.3% non-attributed, and that conversely, C. coli strains from water were predominantly non-attributed (94.3%) and 5.7% attributed to poultry. Considering the protein profiles with a threshold of 94% and 97% of similarity, respectively, strains from surface water could be attributed to poultry (31.4% and 17.1%), and to cattle (17.1% and 5.7%); 54.1% and 77.1% were non-attributed. This study confirmed these livestock animals might contribute to the contamination of surface water, with a level of contribution depending on the typing technique and the method of analysis. MALDI-TOF could potentially be an alternative approach for source attribution.

Bacteria play an important role in biogeochemical cycles as they transform and remineralize organic matter. Particles are notable hotspots of activity, hosting particle-attached (PA) communities that can differ largely from their free-living (FL) counterparts. However, long-standing questions remain concerning bacterial community assembly processes and driving factors. This study investigated the FL and PA community compositions and determinants within the Aulne estuary and the Bay of Brest coastal waters (France). Our results revealed that the FL and PA community compositions greatly varied with salinity and season, explaining a larger part of the variance than the sampling fraction. Both the FL and PA communities were driven by deterministic assembly processes and impacted by similar factors. The FL-PA dissimilarity varied across space and time. It decreased in the estuarine stations compared to the freshwater and marine ends, and in summer. Interestingly, a significant proportion of the FL and PA communities' β-diversity and dissimilarity was explained by cohesion, measuring the degree of taxa co-occurrence. This suggested the importance of co-occurrence patterns in shaping the FL and PA community compositions. Our results shed light on the factors influencing estuarine bacterial communities and provide a first step toward understanding their biogeochemical impacts.

Members of the Campylobacter lari group are causative agents of human gastroenteritis and are frequently found in shellfish, marine waters, shorebirds, and marine mammals. Within a One Health context, we used comparative genomics to characterize isolates from a diverse range of sources and geographical locations within Europe and Australia and assess possible transmission of food, animal, and environmental isolates to the human host. A total of 158 C. lari isolates from Australia, Denmark, France, and Germany, which included 82 isolates from human stool and blood, 12 from food, 14 from domestic animal, 19 from waterbirds, and 31 from the environment were analyzed. Genome-wide analysis of the genetic diversity, virulence, and antimicrobial resistance (AMR) traits was carried-out. Most of the isolates belonged to C. lari subsp. lari (Cll; 98, 62.0%), while C. lari subsp. concheus and C. lari urease-positive thermotolerant Campylobacter (UPTC) were represented by 12 (7.6%) and 15 (9.5%) isolates, respectively. Furthermore, 33 (20.9%) isolates were not assigned a subspecies and were thus attributed to distant Campylobacter spp. clades. Whole-genome sequence-derived multilocus sequence typing (MLST) and core-genome MLST (cgMLST) analyses revealed a high genetic diversity with 97 sequence types (STs), including 60 novel STs and 14 cgMLST clusters (≤10 allele differences), respectively. The most prevalent STs were ST-21, ST-70, ST-24, and ST-58 (accounting for 13.3%, 4.4%, 3.8%, and 3.2% of isolates, respectively). A high prevalence of the 125 examined virulence-related loci (from 76.8 to 98.4% per isolate) was observed, especially in Cll isolates, suggesting a probable human pathogenicity of these strains. IMPORTANCE Currently, relatedness between bacterial isolates impacting human health is easily monitored by molecular typing methods. These approaches rely on discrete loci or whole-genome sequence (WGS) analyses. Campylobacter lari is an emergent human pathogen isolated from diverse ecological niches, including fecal material from humans and animals, aquatic environments, and seafood. The presence of C. lari in such diverse sources underlines the importance of adopting an integrated One Health approach in studying C. lari population structure for conducting epidemiological risk assessment. This retrospective study presents a comparative genomics analysis of C. lari isolates retrieved from two different continents (Europe and Australia) and from different sources (human, domestic animals, waterbirds, food, and environment). It was designed to improve knowledge regarding C. lari ecology and pathogenicity, important for developing effective surveillance and disease prevention strategies.

The detection of viruses and bacteria which can pose a threat either to shellfish health or shellfish consumers remains difficult. The current detection methods rely on point sampling of water, a method that gives a snapshot of the microorganisms present at the time of sampling. In order to obtain better representativeness of the presence of these microorganisms over time, we have developed passive sampling using the adsorption capacities of polymer membranes. Our objectives here were to assess the feasibility of this methodology for field detection. Different types of membrane were deployed in coastal waters over 2 years and the microorganisms tested using qPCR were: human norovirus (NoV) genogroups (G)I and II, sapovirus, Vibrio spp. and the species Vibrio alginolyticus, V. cholerae, V. vulnificus, and V. parahaemolyticus, OsHV-1 virus, and bacterial markers of fecal contamination. NoV GII, Vibrio spp., and the AllBac general Bacteroidales marker were quantified on the three types of membrane. NoV GII and OsHV-1 viruses followed a seasonal distribution. All membranes were favorable for NoV GII detection, while Zetapor was more adapted for OsHV-1 detection. Nylon was more adapted for detection of Vibrio spp. and the AllBac marker. The quantities of NoV GII, AllBac, and Vibrio spp. recovered on membranes increased with the duration of exposure. This first application of passive sampling in seawater is particularly promising in terms of an early warning system for the prevention of contamination in oyster farming areas and to improve our knowledge on the timing and frequency of disease occurence.

Human and animal fecal pollution may adversely affect inland and coastal waters with negative consequences for water supplies, recreational water uses and shellfish production. Fecal pollution of waters is a significant health risk and can lead to economic losses due to shellfish bed closures, bathing prohibitions and serious limitations on water resources. Fecal contamination in water is currently evaluated by the enumeration of traditional fecal indicator bacteria (FIB; i.e., Escherichia coli and intestinal enterococci) which are not indicating the fecal pollution source. Microbial source tracking (MST) methods allow the identification of fecal pollution sources that is critical for management and remediation of water quality. This special issue in Frontiers in Microbiology section Microbiotechnology offers the collection of 19 original research manuscripts, which contribute to the current knowledge on the microbial source tracking and highlight the latest developments.

Fecal pollution in coastal areas is of a high concern since it affects bathing and shellfish harvesting activities. Wild waterbirds are non-negligible in the overall signal of the detectable pollution. Yet, studies on wild waterbirds’ gut microbiota focus on migratory trajectories and feeding impact on their shape, rare studies address their comparison to other sources and develop quantitative PCR (qPCR)-based Microbial Source Tracking (MST) markers to detect such pollution. Thus, by using 16S rRNA amplicon high-throughput sequencing, the aims of this study were (i) to explore and compare fecal bacterial communities from wild waterbirds (i.e., six families and 15 species, n = 275 samples) to that of poultry, cattle, pigs, and influent/effluent of wastewater treatment plants ( n = 150 samples) and (ii) to develop new MST markers for waterbirds. Significant differences were observed between wild waterbirds and the four other groups. We identified 7,349 Amplicon Sequence Variants (ASVs) from the hypervariable V3–V4 region. Firmicutes and Proteobacteria and, in a lesser extent, Actinobacteria and Bacteroidetes were ubiquitous while Fusobacteria and Epsilonbacteraeota were mainly present in wild waterbirds. The clustering of samples in non-metric multidimensional scaling (NMDS) ordination indicated a by-group clustering shape, with a high diversity within wild waterbirds. In addition, the structure of the bacterial communities was distinct according to bird and/or animal species and families (Adonis R 2 = 0.13, p = 10 –4 , Adonis R 2 = 0.11, p = 10 –4 , respectively). The Analysis of Composition of Microbiomes (ANCOM) showed that the wild waterbird group differed from the others by the significant presence of sequences from Fusobacteriaceae ( W = 566) and Enterococcaceae ( W = 565) families, corresponding to the Cetobacterium ( W = 1427) and Catellicoccus ( W = 1427) genera, respectively. Altogether, our results suggest that some waterbird members present distinct fecal microbiomes allowing the design of qPCR MST markers. For instance, a swan- and an oystercatcher-associated markers (named Swan_2 and Oyscab, respectively) have been developed. Moreover, bacterial genera harboring potential human pathogens associated to bird droppings were detected in our dataset, including enteric pathogens, i.e., Arcobacter , Clostridium , Helicobacter , and Campylobacter , and environmental pathogens, i.e., Burkholderia and Pseudomonas . Future studies involving other wildlife hosts may improve gut microbiome studies and MST marker development, helping mitigation of yet unknown fecal pollution sources.

SummaryBiofilms of heterotrophic bacteria cover organic matter aggregates and constitute hotspots of mineralization, primarily acting through extracellular hydrolytic enzyme production. Nevertheless, regulation of both biofilm and hydrolytic enzyme synthesis remains poorly investigated, especially in estuarine ecosystems. In this study, various bioassays, mass spectrometry and genomics approaches were combined to test the possible involvement of quorum sensing (QS) in these mechanisms. QS is a bacterial cell–cell communication system that relies notably on the emission of N‐acylhomoserine lactones (AHLs). In our estuarine bacterial collection, we found that 28 strains (9%), mainly Vibrio, Pseudomonas and Acinetobacter isolates, produced at least 14 different types of AHLs encoded by various luxI genes. We then inhibited the AHL QS circuits of those 28 strains using a broad‐spectrum lactonase preparation and tested whether biofilm production as well as β‐glucosidase and leucine‐aminopeptidase activities were impacted. Interestingly, we recorded contrasted responses, as biofilm production, dissolved and cell‐bound β‐glucosidase and leucine‐aminopeptidase activities significantly increased in 4%–68% of strains but decreased in 0%–21% of strains. These findings highlight the key role of AHL‐based QS in estuarine bacterial physiology and ultimately on biogeochemical cycles. They also point out the complexity of QS regulations within natural microbial assemblages.

The European epidemic monophasic variant of Salmonella enterica serovar Typhimurium (S. 1,4,[5],12:i:-) characterized by the multi locus sequence type ST34 and the antimicrobial resistance ASSuT profile has become one of the most common serovars in Europe (EU) and the United States (US). In this study, we reconstructed the time-scaled phylogeny and evolution of this Salmonella in Europe. The epidemic S. 1,4,[5],12:i:- ST34 emerged in the 1980s by an acquisition of the Salmonella Genomic Island (SGI)-4 at the 3′ end of the phenylalanine phe tRNA locus conferring resistance to copper and arsenic toxicity. Subsequent integration of the Tn21 transposon into the fljAB locus gave resistance to mercury toxicity and several classes of antibiotics used in food-producing animals (ASSuT profile). The second step of the evolution occurred in the 1990s, with the integration of mTmV and mTmV-like prophages carrying the perC and/or sopE genes involved in the ability to reduce nitrates in intestinal contents and facilitate the disruption of the junctions of the host intestinal epithelial cells. Heavy metals are largely used as food supplements or pesticide for cultivation of seeds intended for animal feed so the expansion of the epidemic S. 1,4,[5],12:i:- ST34 was strongly related to the multiple-heavy metal resistance acquired by transposons, integrative and conjugative elements and facilitated by the escape until 2011 from the regulatory actions applied in the control of S. Typhimurium in Europe. The genomic plasticity of the epidemic S. 1,4,[5],12:i:- was demonstrated in our study by the analysis of the plasmidome. We were able to identify plasmids harboring genes mediating resistance to phenicols, colistin, and fluoroquinolone and also describe for the first time in six of the analyzed genomes the presence of two plasmids (pERR1744967-1 and pERR2174855-2) previously described only in strains of enterotoxigenic Escherichia coli and E. fergusonii.

Metadata and quality control information associated with the British Salmonella Typhimurium dataset collected to develop WGS-based source attribution methods.

The partitioning of pathogenic strains isolated in environmental or human cases to their sources is challenging. The pathogens usually colonize multiple animal hosts, including livestock, which contaminate the food-production chain and the environment (e.g. soil and water), posing an additional public-health burden and major challenges in the identification of the source. Genomic data opens up new opportunities for the development of statistical models aiming to indicate the likely source of pathogen contamination. Here, we propose a computationally fast and efficient multinomial logistic regression source-attribution classifier to predict the animal source of bacterial isolates based on 'source-enriched' loci extracted from the accessory-genome profiles of a pangenomic dataset. Depending on the accuracy of the model's self-attribution step, the modeller selects the number of candidate accessory genes that best fit the model for calculating the likelihood of (source) category membership. The Accessory genes-Based Source Attribution (AB_SA) method was applied to a dataset of strains of Salmonella enterica Typhimurium and its monophasic variant (S. enterica 1,4,[5],12:i:-). The model was trained on 69 strains with known animal-source categories (i.e. poultry, ruminant and pig). The AB_SA method helped to identify 8 genes as predictors among the 2802 accessory genes. The self-attribution accuracy was 80%. The AB_SA model was then able to classify 25 of the 29 S. enterica Typhimurium and S. enterica 1,4,[5],12:i:- isolates collected from the environment (considered to be of unknown source) into a specific category (i.e. animal source), with more than 85% of probability. The AB_SA method herein described provides a user-friendly and valuable tool for performing source-attribution studies in only a few steps. AB_SA is written in R and freely available at https://github.com/lguillier/AB_SA.

Volume 9, no. 1, e01309-19, 2020, [https://doi.org/10.1128/MRA.01309-19][1]. Page 3: Line 3 of Acknowledgments should read as follows. “… and support services) and Catherine Ragimbeau from the Laboratoire National de Sante for providing Illumina raw reads.” [1]: /lookup/doi/10.1128/MRA.

Zoonotic Salmonella causes millions of human salmonellosis infections worldwide each year. Information about the source of the bacteria guides risk managers on control and preventive strategies. Source attribution is the effort to quantify the number of sporadic human cases of a specific illness to specific sources and animal reservoirs. Source attribution methods for Salmonella have so far been based on traditional wet-lab typing methods. With the change to whole genome sequencing there is a need to develop new methods for source attribution based on sequencing data. Four European datasets collected in Denmark (DK), Germany (DE), the United Kingdom (UK) and France (FR) are presented in this descriptor. The datasets contain sequenced samples of Salmonella Typhimurium and its monophasic variants isolated from human, food, animal and the environment. The objective of the datasets was either to attribute the human salmonellosis cases to animal reservoirs or to investigate contamination of the environment by attributing the environmental isolates to different animal reservoirs.

As determined by a hybrid approach combining Oxford Nanopore MinION and Illumina MiniSeq sequence data, Campylobacter armoricus strain CA639 harbored a circular chromosome of 1,688,169 bp with a G+C content of 28.47% and two plasmids named pCA639-1 and pCA639-2, with lengths of 51,123 and 28,139 bp, and G+C contents of 26.5% and 28.45%, respectively.

During a study on the prevalence and diversity of members of the genus Campylobacter in a shellfish-harvesting area and its catchment in Brittany, France, six urease-positive isolates of members of the genus Campylobacter were recovered from surface water samples, as well as three isolates from stools of humans displaying enteric infection in the same period. These strains were initially identified as members of the Campylobacter lari group by MALDI-TOF mass spectrometry and placed into a distinct group in the genus Campylobacter, following atpA gene sequence analysis based on whole-genome sequencing data. This taxonomic position was confirmed by phylogenetic analysis of the 16S rRNA, rpoB and hsp60 (groEL) loci, and an analysis of the core genome that provided an improved phylogenetic resolution. The average nucleotide identity between the representative strain CA656T (CCUG 73571T=CIP 111675T) and the type strain of the most closely related species Campylobacter ornithocola WBE38T was 88.5 %. The strains were found to be microaerobic and anaerobic, motile, non-spore-forming, Gram-stain-negative, spiral-shaped bacteria that exhibit catalase, oxidase and urease activities but not nitrate reduction. This study demonstrates clearly that the nine isolates represent a novel species within the C. lari group, for which the name Campylobacter armoricus is proposed. Here, we present phenotypic and morphological features of the nine strains and the description of their genome sequences. The proposed type strain CA656T has a 1.589 Mbp chromosome with a DNA G+C content of 28.5 mol% and encodes 1588 predicted coding sequences, 38 tRNAs, and 3 rRNA operons.