A mathematical, classical stratification modeling approach to disentangling the impact of weather on infectious diseases: A case study using spatio-temporally disaggregated Campylobacter surveillance data for England and Wales.

Disentangling the impact of the weather on transmission of infectious diseases is crucial for health protection, preparedness and prevention. Because weather factors are co-incidental and partly correlated, we have used geography to separate out the impact of individual weather parameters on other seasonal variables using campylobacteriosis as a case study. Campylobacter infections are found worldwide and are the most common bacterial food-borne disease in developed countries, where they exhibit consistent but country specific seasonality. We developed a novel conditional incidence method, based on classical stratification, exploiting the long term, high-resolution, linkage of approximately one-million campylobacteriosis cases over 20 years in England and Wales with local meteorological datasets from diagnostic laboratory locations. The predicted incidence of campylobacteriosis increased by 1 case per million people for every 5° (Celsius) increase in temperature within the range of 8°-15°. Limited association was observed outside that range. There were strong associations with day-length. Cases tended to increase with relative humidity in the region of 75-80%, while the associations with rainfall and wind-speed were weaker. The approach is able to examine multiple factors and model how complex trends arise, e.g. the consistent steep increase in campylobacteriosis in England and Wales in May-June and its spatial variability. This transparent and straightforward approach leads to accurate predictions without relying on regression models and/or postulating specific parameterisations. A key output of the analysis is a thoroughly phenomenological description of the incidence of the disease conditional on specific local weather factors. The study can be crucially important to infer the elusive mechanism of transmission of campylobacteriosis; for instance, by simulating the conditional incidence for a postulated mechanism and compare it with the phenomenological patterns as benchmark. The findings challenge the assumption, commonly made in statistical models, that the transformed mean rate of infection for diseases like campylobacteriosis is a mere additive and combination of the environmental variables.

Characterization of PglJ, a Glycosyltransferase in the Campylobacter concisus N-Linked Protein Glycosylation Pathway that Expands Glycan Diversity.

The Campylobacter genus of Gram-negative bacteria is characterized by the expression of N-linked protein glycosylation (pgl) pathways. As Campylobacter concisus is an emerging human pathogen, a better understanding of the variation of the biosynthetic pathways across the genus is necessary to identify the relationships between protein glycosylation and disease. The pgl pathways of C. concisus strains have been reported to diverge from other Campylobacter in steps after the biosynthesis of N-acetylgalactosamine-α1,3-N,N'-diacetylbacillosamine-α-1-diphosphate undecaprenyl (GalNAc-diNAcBac-PP-Und), which is catalyzed by PglC and PglA, a phosphoglycosyltransferase (PGT) and a glycosyltransferase (GT), respectively. Here we characterize the PglJ GTs from two strains of C. concisus. Chemical synthesis was employed to access the stereochemically defined glycan donor substrates, uridine diphosphate N-acetyl-d-galactosaminuronic acid (UDP-GalNAcA) and uridine diphosphate N-acetyl-d-glucosaminuronic acid (UDP-GlcNAcA), to allow biochemical investigation of PglJ. Evidence for the PglJ substrate specificity structural determinants for the C6″ carboxylate-containing sugar was obtained through variant-based biochemical assays. Additionally, characterization of a UDP-sugar dehydrogenase encoded in the pgl operon, which is similar to the Pseudomonas aeruginosa WbpO responsible for the oxidization of a UDP-HexNAc to UDP-HexNAcA, supports the availability of a UDP-HexNAcA substrate for a GT that incorporates the modified sugar and provides evidence for the presence of a HexNAcA in the N-linked glycan. Utilizing sequence similarity network (SSN) analysis, we identified conserved sequence motifs among PglJ glycosyltransferases, shedding light on substrate preferences and offering predictive insights into enzyme functions across the Campylobacter genus. These studies now allow detailed characterization of the later steps in the pgl pathway in C. concisus strains and provide insights into enzyme substrate specificity determinants for glycan assembly enzymes.

Dual Glycosyltransferases from Campylobacter concisus Diverge from the Canonical Campylobacter N-Linked Glycan Assembly Pathway.

Species within the Campylobacter genus are recognized as emerging human pathogens. Common to all known members of the genus is the presence of an asparagine-linked glycosylation pathway encoded by the pgl operon. Campylobacter species are divided into two major groups, Group I and Group II. To date, most biochemical studies have focused on the Group I species including Campylobacter jejuni. We recently reported that the Group II Campylobacter concisus pathway deviates from that of Group I by the inclusion of a C-6″-oxidized GalNAc (GalNAcA) at the third position installed by PglJ. Herein, we investigate the diversification of the PglH enzymes that act subsequent to installation of GalNAcA. The majority of pgl operons from Group II species, including C. concisus, encode two GT-B fold glycosyltransferases (GTs), PglH1 and PglH2. As the functions of these GTs were not clear by simple comparison of their sequences to that of C. jejuni PglH, further analyses were required. We show that subsequent to the action of PglJ, PglH2 installs the next HexNAc followed by PglH1 adding a single sugar. These steps diverge from the C. jejuni pathway not only in the identity of the sugar donors (UDP-GlcNAc) but also in installing single sugars rather than acting processively. These biochemical studies were extended via bioinformatics to identify sequence signatures that provide predictive capabilities for unraveling the prokaryotic glycan landscape. Phylogenetic analysis showed early divergence between the C. jejuni PglH orthologs and C. concisus PglH1/PglH2 orthologs, leading to diversification of the final glycan.

Identification of knowledge gaps in whole-genome sequence analysis of multi-resistant thermotolerant Campylobacter spp.

BACKGROUND: Campylobacter spp. is the most frequent cause of bacterial food-borne gastroenteritis and a high priority antibiotic resistant bacterium according to the World Health Organization (WHO). European monitoring of thermotolerant Campylobacter spp. does not reflect the global burden of resistances already circulating within the bacterial population worldwide. METHODS: We systematically compared whole genome sequencing with comprehensive phenotypic antimicrobial susceptibility, analyzing 494 thermotolerant Campylobacter poultry isolates from Vietnam and Germany. Any discrepancy was checked by repeating the wet lab and improving the dry lab part. Selected isolates were additionally analyzed via long-read Oxford Nanopore technology, leading to closed chromosomes and plasmids. RESULTS: Overall, 22 different resistance genes and gene variants (e. g. erm(B), aph(3')-IIIa, aph(2'')-If, catA, lnu(C), blaOXA, sat4) and point mutations in three distinct genes (gyrA, 23S rRNA, rpsL) associated with AMR were present in the Campylobacter isolates. Two AMR genes were missing in the database and one falsely associated with resistance. Bioinformatic analysis based on short-read data partly failed to identify tet(O) and aadE, when the genes were present as duplicate or homologous gene variants. Intriguingly, isolates also contained different determinants, redundantly conferring resistance to chloramphenicol, gentamicin, kanamycin, lincomycin and streptomycin. We found a novel tet(W) in tetracycline sensitive strains, harboring point mutations. Furthermore, analysis based on assemblies from short-read data was impaired to identify full length phase variable aad9, due to variations of the poly-C tract within the gene. The genetic determinant responsible for gentamicin resistance of one isolate from Germany could not be identified. GyrT86I, presenting the main determinant for (fluoro-)quinolone resistance led to a rare atypical phenotype of ciprofloxacin resistance but nalidixic acid sensitivity. Long-read sequencing predicted AMR genes were mainly located on the chromosome, and rarely on plasmids. Predictions from long- and short-read sequencing, respectively, often differed. AMR genes were often organized in multidrug resistance islands (MDRI) and partially located in proximity to transposase genes, suggesting main mobilization of resistance determinants is via natural transformation and transposition in Campylobacter. CONCLUSIONS: The results of this study suggest that there is frequent resistance gene duplication, mosaicism, and mutation leading to gene variation and truncation in Campylobacter strains that have not been reported in previous studies and are missing from databases. Furthermore, there is a need for deciphering yet unknown resistance mechanisms and resistance spread in thermotolerant Campylobacter spp. that may pose a challenge to global food safety.

Predictive Mapping of Antimicrobial Resistance for Escherichia coli, Salmonella, and Campylobacter in Food-Producing Animals, Europe, 2000-2021.

In Europe, systematic national surveillance of antimicrobial resistance (AMR) in food-producing animals has been conducted for decades; however, geographic distribution within countries remains unknown. To determine distribution within Europe, we combined 33,802 country-level AMR prevalence estimates with 2,849 local AMR prevalence estimates from 209 point prevalence surveys across 31 countries. We produced geospatial models of AMR prevalence in Escherichia coli, nontyphoidal Salmonella, and Campylobacter for cattle, pigs, and poultry. We summarized AMR trends by using the proportion of tested antimicrobial compounds with resistance >50% and generated predictive maps at 10 × 10 km resolution that disaggregated AMR prevalence. For E. coli, predicted prevalence rates were highest in southern Romania and southern/eastern Italy; for Salmonella, southern Hungary and central Poland; and for Campylobacter, throughout Spain. Our findings suggest that AMR distribution is heterogeneous within countries and that surveillance data from below the country level could help with prioritizing resources to reduce AMR.

Antimicrobial susceptibilities of Campylobacter fetus: report from a reference laboratory.

Campylobacter fetus is known to cause human disease, particularly in elderly and immunocompromised hosts. There are limited published data for antimicrobial susceptibility patterns with this organism, and no interpretive criteria are available. We reviewed antimicrobial susceptibilities of C. fetus isolates tested at a tertiary care center and reference laboratory over an 11-year period. C. fetus isolates from patients treated at Mayo Clinic and those sent as referrals for identification and susceptibility were included. Antimicrobial susceptibility testing was performed using agar dilution for ciprofloxacin, doxycycline, erythromycin, gentamicin, meropenem, and tetracycline. Geographic distribution, culture source, organism minimal inhibitory concentration (MIC) distributions, and MIC50 and MIC90 were examined. Excluding duplicates, 105 unique isolates were identified from 110 positive cultures. Blood cultures represented the most common source, followed by body fluids, skin and soft tissue, and central nervous system. Gentamicin and meropenem had favorable MIC50 and MIC90 of 1 µg/mL. Ciprofloxacin demonstrated an MIC50 of 1 µg/mL; however, the MIC90 was >2 µg/mL. Erythromycin demonstrated MIC50 and MIC90 of 2 µg/mL. Tetracycline and doxycycline were tested on a limited number of isolates and showed a wide range of MICs. Gentamicin and meropenem demonstrated favorable MICs in C. fetus isolates. These may represent therapeutic options for consideration in serious C. fetus infections, pending susceptibility results. Ciprofloxacin, which showed variable results, may be more appropriate for use only after susceptibility testing. C. fetus interpretive criteria are needed to aid clinicians in selection of both empiric and definitive therapies. IMPORTANCE: Our findings contribute to the scant literature on Campylobacter fetus antimicrobial susceptibility test results. We used a reference test method of agar dilution and provide MICs for a large number of organisms and antimicrobial agents.

Genetic recombination-mediated evolutionary interactions between phages of potential industrial importance and prophages of their hosts within or across the domains of Escherichia, Listeria, Salmonella, Campylobacter, and Staphylococcus.

BACKGROUND: The in-depth understanding of the role of lateral genetic transfer (LGT) in phage-prophage interactions is essential to rationalizing phage applications for human and animal therapy, as well as for food and environmental safety. This in silico study aimed to detect LGT between phages of potential industrial importance and their hosts. METHODS: A large array of genetic recombination detection algorithms, implemented in SplitsTree and RDP4, was applied to detect LGT between various Escherichia, Listeria, Salmonella, Campylobacter, Staphylococcus, Pseudomonas, and Vibrio phages and their hosts. PHASTER and RAST were employed respectively to identify prophages across the host genome and to annotate LGT-affected genes with unknown functions. PhageAI was used to gain deeper insights into the life cycle history of recombined phages. RESULTS: The split decomposition inferences (bootstrap values: 91.3-100; fit: 91.433-100), coupled with the Phi (0.0-2.836E-12) and RDP4 (P being well below 0.05) statistics, provided strong evidence for LGT between certain Escherichia, Listeria, Salmonella, and Campylobacter virulent phages and prophages of their hosts. The LGT events entailed mainly the phage genes encoding for hypothetical proteins, while some of these genetic loci appeared to have been affected even by intergeneric recombination in specific E. coli and S. enterica virulent phages when interacting with their host prophages. Moreover, it is shown that certain L. monocytogenes virulent phages could serve at least as the donors of the gene loci, involved in encoding for the basal promoter specificity factor, for L. monocytogenes. In contrast, the large genetic clusters were determined to have been simultaneously exchanged by many S. aureus prophages and some Staphylococcus temperate phages proposed earlier as potential therapeutic candidates (in their native or modified state). The above genetic clusters were found to encompass multiple genes encoding for various proteins, such as e.g., phage tail proteins, the capsid and scaffold proteins, holins, and transcriptional terminator proteins. CONCLUSIONS: It is suggested that phage-prophage interactions, mediated by LGT (including intergeneric recombination), can have a far-reaching impact on the co-evolutionary trajectories of industrial phages and their hosts especially when excessively present across microbially rich environments.

Investigation of Aliarcobacter spp. and Campylobacter spp. in uterine contents of cows: Antibacterial susceptibility and phylogenetic analysis of the isolates.

The study aimed to isolate and identify Aliarcobacter spp. and Campylobacter spp. from the uterine contents of cows and to determine the susceptibilities of the isolates to various antibiotics. For this purpose, a total of 63 cows (with repeat breeder, metritis, and healthy) uterine contents were collected from a slaughterhouse. Pre-enrichment and membrane filtration methods were used to isolate Aliarcobacter and Campylobacter spp., and phenotypic and molecular methods were used to identify the isolates. Antibacterial susceptibilities of the isolates were determined by the disc diffusion method. A total of 11 (17.46 %, 11/63) samples were found positive for both genera, and 12 isolates were obtained from these samples. Out of 9 Campylobacter isolates, 5, 3, and 1 were identified as C. jejuni, C. sputorum, and C. hyointestinalis, respectively. Also, two and one of Aliarcobacter spp. isolates were identified as Aliarcobacter sp. and A. butzleri, respectively. All isolates of both genera were found to be sensitive to amoxicillin-clavulanic acid, ampicillin, erythromycin, and enrofloxacin and resistant to trimethoprim + sulfamethoxazole. This is the first study that reported on the isolation of C. hyointestinalis from cattle uterine contents. It was concluded that Campylobacter and Aliarcobacter species should be considered among the most important etiological agents in uterine infections that cause infertility in cows. The isolation of Aliarcobacter and Campylobacter spp. from healthy cow uteri within the scope of this study suggests the possibility that these agents could colonize the uterus, similar to the colonization observed in the intestine and gallbladder.

Campylobacter devanensis sp. nov., Campylobacter porcelli sp. nov., and Campylobacter vicugnae sp. nov., three novel Campylobacter lanienae-like species recovered from swine, small ruminants, and camelids.

In a previous study characterizing Campylobacter strains deficient in selenium metabolism, 50 strains were found to be similar to, but distinct from, the selenonegative species Campylobacter lanienae. Initial characterization based on multilocus sequence typing and the phylogeny of a set of 20 core genes determined that these strains form three putative taxa within the selenonegative cluster. A polyphasic study was undertaken here to further clarify their taxonomic position within the genus. The 50 selenonegative strains underwent phylogenetic analyses based on the sequences of the 16S rRNA gene and an expanded set of 330 core genes. Standard phenotypic testing was also performed. All strains were microaerobic and anaerobic, Gram-negative, spiral or curved cells with some displaying coccoid morphologies. Strains were motile, oxidase, catalase, and alkaline phosphatase positive, urease negative, and reduced nitrate. Strains within each clade had unique phenotypic profiles that distinguished them from other members of the genus. Core genome phylogeny clearly placed the 50 strains into three clades. Pairwise average nucleotide identity and digital DNA-DNA hybridization values were all below the recommended cut-offs for species delineation with respect to C. lanienae and other related Campylobacter species. The data presented here clearly show that these strains represent three novel species within the genus, for which the names Campylobacter devanensis sp. nov. (type strain RM3662T=LMG 33097T=NCTC 15074T), Campylobacter porcelli sp. nov. (type strain RM6137T=LMG 33098T=CCUG 77054T=NCTC 15075T) and Campylobacter vicugnae sp. nov. (type strain RM12175T=LMG 33099T=CCUG 77055T=NCTC 15076T) are proposed.

Campylobacter californiensis sp. nov., isolated from cattle and feral swine.

Nine Campylobacter strains were isolated from cattle and feral swine faeces: three were recovered during a 2007 Campylobacter-associated outbreak linked to a dairy, and the other six were isolated during a 2009-2010 survey of farms and ranches in Central California. The species identification of these strains could not be determined by 16S rRNA gene sequencing but were most similar to Campylobacter concisus and Campylobacter mucosalis. Additional atpA typing indicated that the nine strains composed a discrete novel clade related to C. concisus and C. mucosalis. A polyphasic study was undertaken here to clarify their taxonomic position. Phylogenetic analyses were performed based on 16S rRNA gene sequences and the concatenated sequences of 330 core genes. The core gene analysis placed the nine strains into a clade well separated from the other Campylobacter taxa, indicating that these strains represent a novel Campylobacter species. Pairwise digital DNA-DNA hybridization and average nucleotide identity values between these strains and other campylobacters are lower than 16 and 73%, respectively, further supporting their placement into a novel taxon. Standard phenotypic testing was performed. All strains are microaerobic or anaerobic, motile, Gram-negative, slightly-curved rods that are oxidase positive but catalase negative. Strains can be distinguished from the other catalase-negative Campylobacter species using phenotypic markers such as motility, oxidase activity, cephalothin resistance, hippuricase activity, growth at 30 °C, and α-haemolysis. The data presented here show that these strains represent a novel species within Campylobacter, for which the name Campylobacter californiensis sp. nov. (type strain RM6914T=LMG 32304T=CCUG 75329T) is proposed.

Human Campylobacter spp. infections in Italy.

PURPOSE: Campylobacter is a frequent cause of enteric infections with common antimicrobial resistance issues. The most recent reports of campylobacteriosis in Italy include data from 2013 to 2016. We aimed to provide national epidemiological and microbiological data on human Campylobacter infections in Italy during the period 2017-2021. METHODS: Data was collected from 19 Hospitals in 13 Italian Regions. Bacterial identification was performed by mass spectrometry. Antibiograms were determined with Etest or Kirby-Bauer (EUCAST criteria). RESULTS: In total, 5419 isolations of Campylobacter spp. were performed. The most common species were C. jejuni (n = 4535, 83.7%), followed by C. coli (n = 732, 13.5%) and C. fetus (n = 34, 0.6%). The mean age of patients was 34.61 years and 57.1% were males. Outpatients accounted for 54% of the cases detected. Campylobacter were isolated from faeces in 97.3% of cases and in 2.7% from blood. C. fetus was mostly isolated from blood (88.2% of cases). We tested for antimicrobial susceptibility 4627 isolates (85.4%). Resistance to ciprofloxacin and tetracyclines was 75.5% and 54.8%, respectively; resistance to erythromycin was 4.8%; clarithromycin 2% and azithromycin 2%. 50% of C. jejuni and C. coli were resistant to ≥ 2 antibiotics. Over the study period, resistance to ciprofloxacin and tetracyclines significantly decreased (p < 0.005), while resistance to macrolides remained stable. CONCLUSION: Campylobacter resistance to fluoroquinolones and tetracyclines in Italy is decreasing but is still high, while macrolides retain good activity.

Prevalence of multidrug-resistant Campylobacter species in wastewater effluents: A menace of environmental and public health concern.

The prevalence of multidrug-resistant Campylobacter species in wastewater effluents presents a formidable challenge at the intersection of environmental sustainability and public health. This study examined the presence of multidrug-resistant Campylobacter in wastewater effluents in the Eastern Cape Province, South Africa, and its implications for environmental ecosystems and public health. Forty-five samples from household effluent (HHE) and wastewater treatment plant effluent (WWTPE) were collected at different geographical locations within the province between April and September 2022. The counts of the presumptive Campylobacter genus ranged from 5.2 × 103 to 6.03 × 104 CFU/mL for HHE and 4.93 × 103 to 1.04 × 104 CFU/mL for WWTPE. About 42.55% of the samples were positive for Campylobacter species. Five virulence determinants including the cadF and wlaN were detected in all the isolates; however, flgR (19.23%), ciaB, and ceuE (15.38%) were less prevalent. The antibiogram profiles of confirmed Campylobacter isolates revealed high resistance (>55%) against all tested antibiotics ranging from 55.77% (nalidixic acid) to 92.30% (erythromycin), and resistance against the other antibiotics followed the order ciprofloxacin (51.92%), azithromycin (50%), and levofloxacin (48.08%). On the contrary, gentamicin was sensitive against 61.54% of the isolates, followed by imipenem (57.69%) and streptomycin (51.92%). The WWTPE's antibiotic resistance index (ARI) was 0.19, lower than the permitted Krumperman threshold of 0.2; and HHE's ARIs were higher. The isolates' respective multiple antibiotic resistance indexes (MARI) varied between 0.08 and 1.00. Among the phenotypically resistant Campylobacter isolates examined, 21 resistance determinants encoding resistance against ß-lactam, carbapenems, aminoglycosides, phenicol, quinolones, tetracyclines, and macrolides were detected, which explains the phenotypic resistance observed in the study. This study concludes that the wastewaters in the study areas are important reservoirs of multidrug-resistant and potentially pathogenic Campylobacter species, suggesting the need for proper treatment of the wastewaters to eliminate the organisms in the effluents before discharge the final effluent to the receiving watershed.

High Campylobacter diversity in retail chicken: epidemiologically important strains may be missed with current sampling methods.

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.

Burden and epidemiology of Campylobacter species in acute enteritis cases in Burkina Faso.

BACKGROUND: Campylobacter spp. is a significant etiological agent of bacterial gastroenteritis globally. In Burkina Faso (BFA), the actual impact of this pathogen on gastroenteritis is considerably underestimated, primarily due to inadequate surveillance systems. OBJECTIVES: This study aimed to investigate the proportion of Campylobacter species responsible for acute gastroenteritis among patients of all ages in urban and rural areas of BFA, using molecular biology techniques. STUDY DESIGN & METHODS: Between 2018 and 2021, faecal specimens were obtained from 1,295 individuals presenting with acute gastroenteritis. These samples underwent screening for the Campylobacter coli/jejuni/lari complex utilizing real-time polymerase chain reaction (PCR) assays. Subsequently, positive samples were subjected to species-level differentiation through the application of species-specific primers. RESULTS: Campylobacter spp. was detected in 25.0% (324/1,295) of the samples analysed. The majority of positive samples (95%, 308/324) were obtained from children under 5 years of age. Species identification was performed on a subset of 114 isolates, revealing 51 Campylobacter jejuni, 10 Campylobacter coli, and 53 Campylobacter isolates that remained unspeciated. CONCLUSIONS: This study reveals a significant prevalence of Campylobacter species among patients with acute gastroenteritis, with a particularly high incidence observed in children under 5 years of age. Based on these findings, the implementation of routine Campylobacter surveillance in public health laboratories is strongly recommended to better monitor and address this health concern.

Evaluation of the prevalence of Aeromonas spp., Campylobacter spp., and Clostridioides difficile in immunocompromised children with diarrhea.

AIM: Diarrhea is a common disease in immunocompromised patients and can be associated with greater morbidity and even mortality. Therefore, the present study was designed to determine the prevalence of Aeromonas spp., Campylobacter spp., and C. difficile among immunocompromised children. METHODS: This study was conducted on 130 stool samples from patients with diarrhea who had defects in the immune system and were referred to Hazrat Masoumeh Children's Hospital in Qom. Demographic information, clinical symptoms, immune status, and duration of chemotherapy were also recorded for each child. DNAs were extracted from the stool, and then direct PCR assays were done by specific primers for the detection of Aeromonas spp., Campylobacter spp., and toxigenic C. difficile, including tcdA/B and cdtA/B genes. Co-infection in patients was also evaluated. RESULTS: 60.8% and 39.2% were male and female, respectively, with a m ± SD age of 56.72 ± 40.49 months. Most cases of immunocompromised states were related to Acute Lymphocytic Leukemia (77.7%) and Non-Hodgkin Lymphoma (14.6%). 93.1% of patients were undergoing chemotherapy during the study. Among patients, most clinical symptoms were related to bloody diarrhea (98.5%) and fever (92.3%). Based on PCR, 14.6, 9.2, and 1.5% were positive for Aeromonas spp., C. difficile, and C. jejuni, respectively. Among the C. difficile-positive cases, the tcdA gene was only detected in one patient. In total, three co-infections were identified, which included Aeromonas spp./C. difficile (tcdA+), C. jejuni/C. difficile, and C. jejuni/Aeromonas spp. CONCLUSIONS: This is the first study in Iran to investigate the simultaneous prevalence of some pathogens in immunocompromised children with diarrhea. Because Aeromonas spp., Campylobacter spp., and C. difficile are not routinely detected in some laboratories, infections caused by them are underappreciated in the clinic. Our results showed that these pathogens are present in our region and can cause gastroenteritis in children, especially those with underlying diseases. Therefore, increasing the level of hygiene in some areas and controlling bacterial diarrheal diseases should be given more attention by health officials.

Monitoring antimicrobial resistance in Campylobacter isolates of chickens and turkeys at the slaughter establishment level across the United States, 2013-2021.

Foodborne infections with antimicrobial-resistant Campylobacter spp. remain an important public health concern. Publicly available data collected by the National Antimicrobial Resistance Monitoring System for Enteric Bacteria related to antimicrobial resistance (AMR) in Campylobacter spp. isolated from broiler chickens and turkeys at the slaughterhouse level across the United States between 2013 and 2021 were analysed. A total of 1,899 chicken-origin (1,031 Campylobacter coli (C. coli) and 868 Campylobacter jejuni (C. jejuni)) and 798 turkey-origin (673 C. coli and 123 C. jejuni) isolates were assessed. Chicken isolates exhibited high resistance to tetracycline (43.65%), moderate resistance to ciprofloxacin (19.5%), and low resistance to clindamycin (4.32%) and azithromycin (3.84%). Turkey isolates exhibited very high resistance to tetracycline (69%) and high resistance to ciprofloxacin (39%). The probability of resistance to all tested antimicrobials, except for tetracycline, significantly decreased during the latter part of the study period. Turkey-origin Campylobacter isolates had higher odds of resistance to all antimicrobials than isolates from chickens. Compared to C. jejuni isolates, C. coli isolates had higher odds of resistance to all antimicrobials, except for ciprofloxacin. The study findings emphasize the need for poultry-type-specific strategies to address differences in AMR among Campylobacter isolates.

Hemophagocytic lymphohistiocytosis and myopericarditis induced by campylobacter: a case report.

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) is a severe disorder characterized by excessive activation of the immune system, leading to hypercytokinemia and damage to multiple organs. We report a rare case of HLH with myopericarditis caused by Campylobacter infection. CASE PRESENTATION: A 28-year-old male patient with a history of hypertension without medicine control presented at the hospital after a four-day fever, decreasing urine amount, rashes on his trunk and limbs, and other symptoms. He was admitted with a provisional diagnosis of atypical infection and allergic skin rash related to diclofenac. However, his condition deteriorated, and he developed shock, tachycardia, chest distress, and bilateral pleural effusion after admission. Further investigations revealed cardiogenic shock related to myopericarditis, and he was transferred to the ICU. In addition, a stool PCR panel subsequently revealed a positive result for Campylobacter. On day 6, he was diagnosed with HLH. Under Clarithromycin and dexamethasone infusion, leukocytosis, anemia and thrombocytopenia with cardiogenic shock status improved. Then, he was later discharged in stable condition. CONCLUSIONS: HLH and myopericarditis caused by Campylobacter are very rare. Early detection of Campylobacter-induced HLH and multiple organ failure, as well as prompt use of antibiotics and immunosuppressants, can be helpful for prognosis.

The characterization and correlation between the phenotypic and genotypic resistance of Campylobacter spp. isolates from commercial broilers and native chickens in the south of Thailand.

RESEARCH HIGHLIGHTS: High Campylobacter prevalence in chickens; C. jejuni more prevalent than C. coli.Susceptibility to macrolides but resistance to quinolones/tetracyclines in isolates.Homogeneous resistance patterns within farms; higher in broilers than in native birds.Partial association between phenotypic and genotypic resistance among isolates.

Exploring the association of weather variability on Campylobacter - A systematic review.

BACKGROUND: Previous work has found climate change-induced weather variability is suspected to increase the transmission of enteric pathogens, including Campylobacter, a leading cause of bacterial gastroenteritis. While the relationship between extreme weather events and diarrheal diseases has been documented, the specific impact on Campylobacter infections remains underexplored. OBJECTIVE: To synthesize the peer-reviewed literature exploring the effect of weather variability on Campylobacter infections in humans. METHODS: The review included English language, peer-reviewed articles, published up to September 1, 2022 in PubMed, Embase, GEOBASE, Agriculture and Environmental Science Database, and CABI Global Health exploring the effect of an antecedent weather event on human enteric illness caused by Campylobacter (PROSPERO Protocol # 351884). We extracted study information including data sources, methods, summary measures, and effect sizes. Quality and weight of evidence reported was summarized and bias assessed for each article. RESULTS: After screening 278 articles, 47 articles (34 studies, 13 outbreak reports) were included in the evidence synthesis. Antecedent weather events included precipitation (n = 35), temperature (n = 30), relative humidity (n = 7), sunshine (n = 6), and El Niño and La Niña (n = 3). Reviewed studies demonstrated that increases in precipitation and temperature were correlated with Campylobacter infections under specific conditions, whereas low relative humidity and sunshine were negatively correlated. Articles estimating the effect of animal operations (n = 15) found presence and density of animal operations were significantly associated with infections. However, most of the included articles did not assess confounding by seasonality, presence of animal operations, or describe estimates of risk. DISCUSSION: This review explores what is known about the influence of weather events on Campylobacter and identifies previously underreported negative associations between low relative humidity and sunshine on Campylobacter infections. Future research should explore pathogen-specific estimates of risk, which can be used to influence public health strategies, improve source attribution and causal pathways, and project disease burden due to climate change.

Quantifying bacterial evolution in the wild: A birthday problem for Campylobacter lineages.

Measuring molecular evolution in bacteria typically requires estimation of the rate at which nucleotide changes accumulate in strains sampled at different times that share a common ancestor. This approach has been useful for dating ecological and evolutionary events that coincide with the emergence of important lineages, such as outbreak strains and obligate human pathogens. However, in multi-host (niche) transmission scenarios, where the pathogen is essentially an opportunistic environmental organism, sampling is often sporadic and rarely reflects the overall population, particularly when concentrated on clinical isolates. This means that approaches that assume recent common ancestry are not applicable. Here we present a new approach to estimate the molecular clock rate in Campylobacter that draws on the popular probability conundrum known as the 'birthday problem'. Using large genomic datasets and comparative genomic approaches, we use isolate pairs that share recent common ancestry to estimate the rate of nucleotide change for the population. Identifying synonymous and non-synonymous nucleotide changes, both within and outside of recombined regions of the genome, we quantify clock-like diversification to estimate synonymous rates of nucleotide change for the common pathogenic bacteria Campylobacter coli (2.4 x 10-6 s/s/y) and Campylobacter jejuni (3.4 x 10-6 s/s/y). Finally, using estimated total rates of nucleotide change, we infer the number of effective lineages within the sample time frame-analogous to a shared birthday-and assess the rate of turnover of lineages in our sample set over short evolutionary timescales. This provides a generalizable approach to calibrating rates in populations of environmental bacteria and shows that multiple lineages are maintained, implying that large-scale clonal sweeps may take hundreds of years or more in these species.