Campylobacter enteritis in Portugal: epidemiological features and biological markers

Epidemiological Data and Antimicrobial Resistance of Campylobacter spp. in Portugal from 13 Years of Surveillance

This study extensively analyzed campylobacteriosis surveillance in Portugal from 2009 to 2021, aiming to investigate demographic shifts, seasonal variations, and antimicrobial resistance (AMR) within Campylobacter isolates. Surveillance network and sentinel laboratory-based system data revealed a substantial under-notification of campylobacteriosis cases, suggesting an underestimated disease burden. Notification rates exhibited a paradigm shift, with a notable prevalence among the pediatric population, particularly in children aged 1-4 years, diverging from European reports. Additionally, an emerging trend of Campylobacter infections in younger adults (15-44 years) was observed. The study unveiled a unique seasonal distribution of cases, defying typical summer peaks seen elsewhere. AMR analysis revealed high resistance to ciprofloxacin and tetracycline, in both C. jejuni (93.7% and 79.2%, respectively) and C. coli (96.5% and 93.2%, respectively), stable throughout the studied period (2013-2021). C. coli exhibited significantly higher resistance to erythromycin, gentamicin, ampicillin and ertapenem compared to C. jejuni (p < 0.001). Multilocus Sequence Typing (MLST) data demonstrated the distribution of resistance markers across diverse sequence types, challenging the notion of a clonal origin for multidrug-resistant isolates. In conclusion, the study highlights the need for enhanced surveillance and raises concerns about alarming AMR levels, recommending the implementation of whole-genome sequencing (WGS)-based surveillance for a deeper comprehension of disease patterns and an evolving AMR landscape.

Molecular diagnosis of Arcobacter and Campylobacter in diarrhoeal samples among Portuguese patients

The present study was conducted to investigate the prevalence and diversity of Arcobacter and Campylobacter spp. in 298 stool samples of patients with diarrhoea, collected from 22 Portuguese hospitals, between September and November 2012. Detection of Arcobacter and Campylobacter spp. was performed using molecular-based detection techniques, such as real-time fluorescence resonance energy transfer PCR, species-specific PCR, and sequencing of amplified PCR products. Overall, 1.3% of the samples were positive for Arcobacter butzleri and 0.3% for Arcobacter cryaerophilus. Campylobacter spp. were found in 31.9% of diarrhoeic faeces. Campylobacter jejuni and Campylobacter concisus were the most prevalent species (13.7% and 8.0%, respectively). The prevalence of Arcobacter and Campylobacter spp. was significantly different between children and adults (39.7% versus 22.8%, P = 0.003). We underline the high prevalence of these pathogens in diarrhoeal samples among Portuguese patients, with particular relevance in the paediatric age group.

Comparative genotypic and antimicrobial susceptibility analysis of zoonotic Campylobacter species isolated from broilers in a nationwide survey, Portugal

Campylobacter is a major cause of human foodborne disease worldwide and has been associated with the consumption of contaminated poultry. The prevalence of Campylobacter species in broiler flocks from more than 200 producers widespread in mainland Portugal was assessed in 2008 in response to Commission Decision 2007/516/EC. Campylobacter isolates were obtained from 83.3% of 424 pooled cecal samples, with a higher prevalence of Campylobacter coli (61.2%) than Campylobacter jejuni (38.8%). Restriction fragment length polymorphism analysis of the flaA gene (flaA-RFLP) of 112 C. coli isolates and 67 C. jejuni isolates yielded 11 flaA-RFLP patterns with HinfI (Hunter Gaston diversity index [HGDI] = 0.62) and 48 flaA-RFLP patterns with DdeI (HGDI = 0.89), indicating a high level of genetic diversity. A wide geographic distribution of the most frequent restriction pattern was observed. MICs of five antimicrobials (ciprofloxacin, gentamicin, streptomycin, erythromycin, and tetracycline) were determined for 215 C. coli isolates and 136 C. jejuni isolates. The occurrence of non-wild-type isolates, exhibiting an acquired resistance phenotype, was higher for C. coli than C. jejuni for all antimicrobials tested. Sixty-three percent of C. jejuni and C. coli isolates were considered non-wild type based on their response to both ciprofloxacin and erythromycin, which are frequently used in the treatment of human infections. The high prevalence of antimicrobial-resistant Campylobacter strains detected supports the need for increased epidemiological surveillance and prevention in a country where large amounts of poultry meat are consumed.

Characterization of Campylobacter jejuni and Campylobacter coli strains isolated in the region of Nis, Serbia

INTRODUCTION

Campylobacter jejuni and Campylobacter coli represent one of the main causes of bacterial diarrhoea in humans. Although the disease is usually mild and self-limiting, severe chronic sequelae may occur, such as reactive arthritis, Guillain-Barré and Miller Fisher syndromes. Serotyping is used as an epidemiological marker, while post-infective polyneuropathies are associated with several O serotypes.

OBJECTIVE

Strains of C. jejuni and C. coli were serotyped based on heat stable (HS) and heat labile (HL) antigens, as well as biotypes to determine strain diversity.

METHODS

Campylobacter spp. was isolated using selective blood media with antibiotics. Differentiation to the species level was done by a combination of biotyping tests and by a PCR-based RFLP test. The isolates were characterised by Penner and Lior serotyping methods.

RESULTS

The serotypes showed diversity without predominant serotypes. 24 HS serotypes were detected among 29 C. jejuni strains, and seven serotypes among nine C. coli strains. HL serotyping method successfully typed 62.5% of strains. Among 16 C.jejuni strains 14 serotypes were detected, and three among four C. coli strains. A C.jejuni strain associated with a patient with Guillain-Barré syndrome was typed as biotype II, O:19.

CONCLUSION

The biotyping and serotyping results have indicated that C. jejuni and C. coli strains in the region of Nis, Serbia are diverse and could be probably of unrelated sources of origin or reservoirs. The strain associated with the Guillain-Barré syndrome patient was serotype O:19, one of the most common in this post-infective complication.

Etiology of diarrhea in older children, adolescents and adults: a systematic review

Background

Diarrhea is an important cause of morbidity and mortality in all regions of the world and among all ages, yet little is known about the fraction of diarrhea episodes and deaths due to each pathogen.

Methodology/Principal Findings

We conducted a systematic literature review to identify all papers reporting the proportion of diarrhea episodes with positive laboratory tests for at least one pathogen in inpatient, outpatient and community settings that met our inclusion and exclusion criteria. We identified a total of 25,701 papers with possible etiology data and after final screening included 22 papers that met all inclusion and exclusion criteria. Enterotoxigenic Escherichia coli and V. cholerae O1/O139 were the leading causes of hospitalizations. In outpatient settings, Salmonella spp., Shigella spp., and E. histolytica were the most frequently isolated pathogens.

Conclusions/Significance

This is the first systematic review which has considered the relative importance of multiple diarrhea pathogens. The few studies identified suggest that there is a great need for additional prospective studies around the world in these age groups to better understand the burden of disease and the variation by region.

Diarrhea is an important cause of illness and death around the world and among people of all ages, but unfortunately we often do not know what specific bacterium or virus causes the illness. We conducted a review of the scientific literature with the goal of finding published studies that identified bacteria and viruses among patients with diarrhea in the community and in hospital settings. We initially found nearly 26,000 papers on this topic but narrowed the list to 22 studies that met all of our specific criteria for inclusion in our review. Among patients hospitalized for diarrhea, E coli and Vibrio cholerae were found in more than 49% of people living in middle income and poor countries. Among patients who sought care from their doctor on an outpatient basis, Salmonella spp., Shigella spp., and E. histolytica were most often found. In our review we focused on the differences in the distribution of pathogens between patients in inpatient vs. outpatient settings because these estimates may best approximate what we would expect to see if the distribution were applied to global estimates of diarrhea deaths vs. uncomplicated illnesses.

Weather and notified Campylobacter infections in temperate and sub-tropical regions of Australia: an ecological study

BACKGROUND

The relationship between weather and food-borne diseases has been of great concern recently. However, the impact of weather variations on food-borne disease may vary in different areas with various geographic, weather and demographic characteristics. This study was designed to quantify the relationship between weather variables and Campylobacter infections in two Australian cities with different local climatic conditions.

METHODS

An ecological-epidemiological study was conducted, using weekly disease surveillance data and meteorological data, over the period 1990-2005, to quantify the relationship between maximum and minimum temperatures, rainfall, relative humidity and notifications of Campylobacter infections in Adelaide, with a temperate Mediterranean climate, and Brisbane, with a sub-tropical climate. Spearman correlation and time-series adjusted Poisson regression analyses were performed taking into account seasonality, lag effects and long-term trends.

RESULTS

The results indicate that weekly maximum and minimum temperatures were inversely associated with the weekly number of cases in Adelaide, but positively correlated with the number of cases in Brisbane, with relevant lagged effects. The effects of rainfall and relative humidity on Campylobacter infection rates varied in the two cities.

CONCLUSION

Weather might have different effect on Campylobacter infections in different cities. Further studies are needed for a better understanding of these relationships for they may indicate epidemiologic factors important for control of these infections.

Prevalence of Campylobacter within a swine slaughter and processing facility

In this work, the occurrence of Campylobacter in a swine slaughter and processing facility was studied. Thirty composite carcass samples, representing 360 swine carcasses, were taken immediately after exsanguination, immediately after polishing, after the final wash, and after overnight chilling at 2 degrees C. Thirty matching composite rectal samples were also taken immediately after exsanguination, and 60 nonmatching individual colon samples were collected from the same lot of swine during evisceration. Also, 72 environmental samples were collected from equipment used in the slaughter operation (42 samples) and the processing operation (30 samples). Campylobacter was isolated by direct plating on Campy-Line agar (CLA) or Campy-Cefex agar (CCA), as well as by Bolton broth enrichment and subsequent inoculation onto CLA or CCA. For all four recovery methods combined, Campylobacter was detected on 33% (10 of 30) of the composite carcasses immediately after exsanguination, 0% (0 of 30) after polishing, 7% (2 of 30) immediately before chilling, and 0% (0 of 30) after overnight chilling. The pathogen was recovered from 100% (30 of 30) of the composite rectal samples and 80% (48 of 60) of the individual colon samples. Campylobacter was detected in 4.8% (2 of 42) and 3.3% (1 of 30) of the slaughter and processing equipment samples, respectively. The recovery rate achieved with direct plating on CLA was significantly higher (P < 0.05) than those achieved with the other three recovery methods. For the 202 isolates recovered from all of the various samples tested, Campylobacter coli was the predominant species (75%) and was followed by Campylobacter spp. (24%) and Campylobacter jejuni (1%). These results indicate that although Campylobacter is highly prevalent in the intestinal tracts of swine arriving at the slaughter facility, this microorganism does not progress through the slaughtering operation and is not detectable on carcasses after overnight chilling.

A population-based longitudinal study on the incidence and disease burden of gastroenteritis and Campylobacter and Salmonella infection in four regions of The Netherlands

The aim of this study was to estimate the incidence of gastroenteritis and Campylobacter and Salmonella infection in the Dutch population, the disease burden, and the percentage of patients with gastroenteritis that consults a general practitioner. A sample of 6243 persons was invited to participate in the study, i.e. completing a questionnaire and submitting stool samples. The follow-up period was 17 weeks. In total, 2206 persons participated (= 35%), contributing 660 person years. The incidence (standardised by age and gender) of first episodes of gastroenteritis was 45 per 100 person years. Among patients with gastroenteritis, Salmonella and Campylobacter were cultured in 1.6 and 4.5%, respectively. The standardised incidence of first Campylobacter infections was 9 per 100 person years, of first Salmonella infections 4 per 100 person years. For 22% of the episodes of gastroenteritis, a general practitioner was consulted (either by phone or by practice visit). For 52% of the episodes, medicine were used. For 34% of the episodes, absence from school was reported and for 15%, absence from work was reported. Despite of possible biases, we can conclude that the incidence of gastroenteritis is very high and causes considerable use of medication, consultation of general practitioners and absence from work and school.

Detection and identification of Campylobacter coli and Campylobacter jejuni by two-step polymerase chain reaction

Flagellin gene was used as target sequence to detect and distinguish C. coli and C. jejuni by a "nested PCR" technique. The method shows a high level of sensitivity and specificity. Application of this rapid diagnostic tool could provide further information about epidemiological and pathogenetic implications of each of these two microorganisms.

Direct polymerase chain reaction detection of Campylobacter jejuni and Campylobacter coli in raw milk and dairy products

A polymerase chain reaction (PCR) method designed to sensitively detect and identify Campylobacter jejuni and Campylobacter coli without the need for isolating and culturing strains is described. The intergenic sequence between the flagellin genes flaA and flaB was amplified and characterized with a triple primer or seminested primer approach. A total of 50 bacterial strains, 27 of C. jejuni and C. coli and 23 of other species, were tested, giving no false-positive or false-negative results. The detection limit as determined by ethidium bromide staining of amplification products on agarose gels was 10 bacteria or less in artificially contaminated water, milk, and soft cheese samples with the seminested primer PCR assay. As an application of the PCR system, a set of 93 samples of milk and other dairy products was screened for the presence of C. jejuni and C. coli. We identified six positive samples (6.5%), while none were found with a conventional culture method.

Arcobacter cryaerophilus and thermophilic campylobacters in a sewage treatment plant in Italy: two secondary treatments compared

Microaerophilic organisms were monitored in sewage effluent undergoing two secondary treatments: air and oxygen-activated sludge. The mean numbers of Arcobacter cryaerophilus and thermophilic campylobacters detected in incoming sewage were 5639/100 ml and 1720/100 ml respectively. Secondary treatment in air tanks reduced the population of A. cryaerophilus by 97.1% and of thermophilic campylobacters by 99.08%, whereas treatment in oxygen tanks reduced the bacteria 97.8% and 99.63% respectively, showing that oxygen-activated sludge treatment was more effective. Subsequent tertiary treatment with 2 p.p.m. chlorine dioxide evidenced the removal of A. cryaerophilus to 99.9% and eliminated thermophilic campylobacters. Campylobacter jejuni and C. coli constituted 54.1% and 45.9% of 74 thermophilic campylobacter strains isolated. In air-activated sludge effluent C. jejuni was found more often, thus appearing more sensitive to oxygen. The most probable number assay used for detection of campylobacters, blood medium for enrichment and blood-free medium for plating, also appeared to be fit for A. cryaerophilus, the high density of which in urban sewage may be due to inflows from slaughterhouses.

Prevalence, biotypes, plasmid profile and antimicrobial resistance of Campylobacter isolated from wild and domestic animals from northeast Portugal

The incidence of Campylobacter jejuni and Campylobacter coli in wild and producing animals has been studied to evaluate their importance as potential reservoirs of campylobacter infection. These organisms were isolated from: 59 chicken (60.2%), 65 swine (59.1%), 31 black rats (57.4%), 61 sparrows (45.5%), 21 ducks (40.5%), 32 cows (19.5%) and 27 sheep (15.3%). Biotypes, plasmid and resistance profiles were studied in order to characterize the isolates. Biotypes I and II of C. jejuni were predominant in all reservoirs except swine, where C. coli I was more frequent. Plasmid prevalence was higher in strains isolated from swine (53.8%) and rats (45.5%). The size of the plasmids ranged from 1.3 to 82 MDa. A 2.3 MDa plasmid was the most frequent, detected in all the reservoirs except ducks. Antimicrobial susceptibility testing revealed that 5.5% of the strains were resistant to ampicillin, 5.5% to tetracycline, 12.6% to erythromycin and 23.5% to streptomycin. Resistance to erythromycin (26.2%) and to streptomycin (58.4%) was particularly high in isolates from swine. Tetracycline resistance was encoded by a 33 or a 41 MDa plasmid and transferred by conjugation.