Prevalence of Arcobacter: From farm to retail – A systematic review and meta-analysis

Arcobacter species in milk contamination: a prevalence-based systematic review and meta-analysis

AIMS

Milk is consumed raw or minimally processed and plays a role in the dissemination of pathogens of public health concerns. The present investigation is aimed at assessing the occurrence of pathogenic Arcobacter species in 2945 milk samples.

METHODS AND RESULTS

Arcobacter data systematically retrieved from five repositories until 20 February 2022 according to PRISMA principles were logit transformed and fitted using a generalized linear mixed-effects model. The between-study heterogeneity was estimated as I2-value. Leave-one-out cross-validation and funnel plot with Egger's tests were used to assess the hardiness and bias in the model. The global prevalence of Arcobacter genus in the milk was 12% [95% confidence interval (CI): 7-19%; I2 = 87.3%, 95% CI: 83.0-90.6%] and no publication bias observed (Egger's test: P = 0.112). Arcobacter genus prevalence in milk was 13% (95% CI: 5-30%), 10% (95% CI: 1-46%), and 9% (95% CI: 4-19%) in Europe, South America, and Asia, respectively. Arcobacter butzleri was the most prevalent [8% (95% CI: 4-13%)], followed by A. cryaerophilus [0.6% (95% CI: 0.2-33.2%)] and A. skirrowii [0.19% (95% CI: 0.03-1.2%)]. Also, species-specific prevalence of A. butzleri, A. cryaerophilus, and A. skirrowii varied continentally, but the test for species-specific/continental differences was not significantly different (P > 0.5).

The Prevalence of Aliarcobacter Species in the Fecal Microbiota of Farm Animals and Potential Effective Agents for Their Treatment: A Review of the Past Decade

There is an endless demand for livestock-originated food, so it is necessary to elucidate the hazard points for livestock breeding. Pathogens are one of the hazard points that threaten the biosecurity of farm-animal breeding and public health. As a potential foodborne pathogen, Aliarcobacter is a member of the intestinal microbiota of farm animals with and without diarrhea. Aliarcobacter spp. are capable of colonizing livestock intestines and are transmitted through the feces. Hence, they endanger slaughterhouses and milk products with fecal contamination. They also have other, rarer, vertical and horizontal transmission routes, including the offspring that abort in farm animals. Gastrointestinal symptoms and abort cases demonstrate potential financial losses to the industry. Viewed from this perspective, the global circulation of farm-animal products is a significant route for zoonotic agents, including Aliarcobacter. In the last decade, worldwide prevalence of Aliarcobacter in fecal samples has ranged from 0.8% in Italy to 100% in Turkey. Furthermore, antibiotic resistance is recognized as a new type of environmental pollutant and has become a hot topic in animal breeding and the food industry. Increasing antibiotic resistance has become a significant problem impacting productivity. The increase in antimicrobial resistance rates in Aliarcobacter is caused by the misuse of antimicrobial drugs in livestock animals, leading to the acquiring of resistance genes from other bacteria, as well as mutations in current resistance genes. The most resistant strains are A. butzleri, A. cryaerophilus, and A. skirrowii. This review analyzes recent findings from the past decade on the prevalence of Aliarcobacter in the intestinal microbiota and the current effective antibiotics against Aliarcobacter. The paper also highlights that A. cryaerophilus and A. skirrowii are found frequently in diarrheal feces, indicating that Aliarcobacter should be studied further in livestock diarrheal diseases. Moreover, Aliarcobacter-infected farm animals can be treated with only a limited number of antibiotics, such as enrofloxacin, doxycycline, oxytetracycline, and gentamicin.

Campylobacter jejuni and Other Emerging Campylobacteraceae in Retail Beef Liver - An Underestimated Potential Source?

Bovine by-products, such as liver, could be an underestimated source of Campylobacter jejuni. Therefore, our aims were to evaluate the occurrence of C. jejuni and other Campylobacteraceae in retail beef liver and characterize their antibiotic resistance (ciprofloxacin, tetracycline, erythromycin, and gentamicin) and potential genetic relationship by flagellin gene Restriction Fragment Length Polymorphism (flaA-RFLP) and Multilocus Sequence Typing (MLST) with clinical strains. Seventy-six out of 206 samples (36.9%) were positive for Campylobacter and related organisms. Arcobacter butzleri was the most frequently isolated species (21.8%), followed by C. jejuni (9.7%), C. fetus (7.8%) and C. coli (1%). The C. jejuni strains showed resistance to tetracycline (17.2%) or ciprofloxacin (6.9%), with only one strain resistant to both antibiotics. Meanwhile, 8.3% of ciprofloxacin resistance was observed in C. fetus. The other species showed no resistance. Most of the clonal complexes (CC) in which the C. jejuni genotypes were grouped (CC-21, 42, 48 and 52), coincided with genotypes of clinical strains previously reported in Chile. As such, this study provides evidence that beef liver could be an underestimated route for resistant C. jejuni to humans. Further studies should assess whether this food could play a role in the transmission of other emerging Campylobacteraceae such as those reported here.

Antibiotics and microbial community-induced antibiotic-resistant genes distribution in soil and sediment in the eastern coastline of China

The health risk of antibiotic-resistant genes (ARGs) has been a global concern, while the report on occurrence and prevalence of ARGs in coastal zone is relatively scarce. This study investigated typical ARGs in soil and sediment in coastal line of eastern China and assessed its relationship with antibiotics and heavy metals as well as microbial community. Results showed that eight ARGs were all detected in the samples, and β-lactam resistance gene blaTEM reached the highest absolute abundance (6.28 × 10⁷ ~ 6.48 × 10⁸ copies/g) and relative abundance (2.3 × 10^-2 copies/16S rRNA) among samples. Amoxicillin and tetracycline were most frequently detected with the average concentration of 2.28 μg/kg and 3.48 μg/kg, respectively. Cr and Zn were found to be most abundant heavy metals with average value of 82.1 and 59.1 mg/kg, respectively. Proteobacteria, Campilobacterota, Bacteroidota, and Firmicutes were dominant phyla in most samples, while bacterial community varied significantly among samples. Redundancy analyses (RDA) showed that microbial community and antibiotics (amoxicillin and tetracycline) were driving factors of ARGs distribution, while heavy metals were not significantly correlated with ARGs. This study is helpful to understand the fate of ARGs in coastal zone.

The Prevalence of Arcobacteraceae in Aquatic Environments: A Systematic Review and Meta-Analysis

Members of the family Arcobacteraceae are distributed widely in aquatic environments, and some of its species have been associated with human and animal illness. However, information about the diversity and distribution of Arcobacteraceae in different water bodies is still limited. In order to better characterize the health risk posed by members in the family Arcobacteraceae, a systematic review and meta-analysis-based method was used to investigate the prevalence of Arcobacteraceae species in aquatic environments based on available data published worldwide. The database search was performed using related keywords and considering studies up to February 2021. The pooled prevalence in aquatic environments was 69.2%, ranging from 0.6 to 99.9%. These bacteria have a wide geographical distribution, being found in diverse aquatic environments with the highest prevalence found in raw sewage and wastewater treatment plants (WWTP), followed by seawater, surface water, ground water, processing water from food processing plants and water for human consumption. Assessing the effectiveness of treatments in WWTP in eliminating this contamination, it was found that the wastewater treatment may not be efficient in the removal of Arcobacteraceae. Among the analyzed Arcobacteraceae species, Al. butzleri was the most frequently found species. These results highlight the high prevalence and distribution of Arcobacteraceae in different aquatic environments, suggesting a risk to human health. Further, it exposes the importance of identifying and managing the sources of contamination and taking preventive actions to reduce the burden of members of the Arcobacteraceae family.