Fluoroquinolone-Resistant Salmonella enterica, Campylobacter spp., and Arcobacter butzleri from Local and Imported Poultry Meat in Kumasi, Ghana

Molecular characterization of antibiotic resistant Salmonella enterica across the poultry production chain in Costa Rica: A cross-sectional study

Antibiotic resistant Salmonella enterica are on the increase, worldwide. Given the scarcity of data, this study aimed to investigate its occurrence, virulence, and antibiotic resistance in Costa Rica's food chain. In total, 65 chicken meat- and 171 chicken caecal samples were collected and examined for Salmonella. High frequencies of Salmonella were found in chicken meat (58.5 %, n/N = 38/65) and poultry farms (38.0 %, n/N = 65/171). The majority of Salmonella from chicken meat (89.5 %, n/N = 34/38) and caecum samples (93.6 %, n/N = 59/63) exhibited multidrug resistance (MDR). Serovar Infantis was the most prevalent (94 %, n/N = 67/71), followed by serovars Anatum and Kentucky (3 %, n/N = 2/71). A pESI-like plasmid (92 %, n/N = 65/71) containing virulence and resistance markers was found in S. Infantis. Given the high prevalence of MDR Salmonella, this study emphasizes the need to enhance surveillance systems for foodborne pathogens and antimicrobial resistance in Costa Rica's food production chain.

Prevalence and Serotype of Poultry Salmonellosis in Africa: a Systemic Review and Meta-Analysis

Salmonellosis represents a significant economic and public health concern for the poultry industry in Africa, leading to substantial economic losses due to mortality, reduced productivity, and food safety problems. However, comprehensive information on the burden of poultry salmonellosis at the continental level are scarce. To address this gap, a systemic review and meta-analysis were conducted to consolidate information on the prevalence and circulating serotypes of poultry salmonellosis in African countries. This involved the selection and review of 130 articles published between 1984 and 2021. A detailed systematic review protocol was structured according to Cochrane STROBE and PRISMA statement guidelines. From the 130 selected articles from 23 different African countries, the overall pooled prevalence estimate (PPE) of poultry salmonellosis in Africa was found to be 14.4% (95% CI= 0.145-0.151). Cameroon reported the highest PPE at 71.9%, with the country also noting the highest specific prevalence of 93.3%. The PPE was notably high in meat and meat products at 23%, indicating significant contamination of Salmonella in African poultry meat and meat products. The number of research papers reporting poultry salmonellosis in Africa has been a threefold increase from 1984 to 2021. Salmonella Enteritidis and Typhimurium were the two most prevalent serotypes reported in 18 African countries. Besides, Salmonella Kentucky, Virchow, Gallinarum, and Pullorum were also widely reported. Western Africa had the highest diversity of reported Salmonella serotypes (141), in contrast to southern Africa, which reported only 27 different serotypes. In conclusion, poultry salmonellosis is highly prevalent across Africa, with a variety of known serotypes circulating throughout the continent. Consequently, it is crucial to implement strategic plans for the prevention and control of Salmonella in Africa.

Antibiotic-Resistant Arcobacter spp. in commercial and smallholder farm animals in Asante Akim North Municipality, Ghana and Korogwe Town Council, Tanzania: a cross-sectional study

BACKGROUND

Arcobacter species are considered emerging foodborne pathogens that can potentially cause serious infections in animals and humans. This cross-sectional study determined the frequency of potentially pathogenic Arcobacter spp. in both commercial and smallholder farm animals in Ghana and Tanzania. A total of 1585 and 1047 (poultry and livestock) samples were collected in Ghana and Tanzania, respectively. Selective enrichment media, along with oxidase and Gram testing, were employed for isolation of suspected Arcobacter spp. and confirmation was done using MALDI-TOF MS. Antibiotic susceptibility was assessed through disk diffusion method and ECOFFs were generated, for interpretation, based on resulting inhibition zone diameters.

RESULTS

The overall Arcobacter frequency was higher in Ghana (7.0%, n = 111) than in Tanzania (2.0%, n = 21). The frequency of Arcobacter in commercial farms in Ghana was 10.3% (n/N = 83/805), while in Tanzania, it was 2.8% (n/N = 12/430). Arcobacter was detected in only 3.6% (n/N = 28/780) of the samples from smallholder farms in Ghana and 1.5% (n/N = 9/617) of the samples from Tanzania. For commercial farms, in Ghana, the presence of Arcobacter was more abundant in pigs (45.1%, n/N = 37/82), followed by ducks (38.5%, n/N = 10/26) and quails (35.7%, n/N = 10/28). According to MALDI-TOF-based species identification, Arcobacter butzleri (91.6%, n/N = 121/132), Arcobacter lanthieri (6.1%, n/N = 8/132), and Arcobacter cryaerophilus (2.3%, n/N = 3/132) were the only three Arcobacter species detected at both study sites. Almost all of the Arcobacter from Ghana (98.2%, n/N = 109/111) were isolated during the rainy season. The inhibition zone diameters recorded for penicillin, ampicillin, and chloramphenicol allowed no determination of an epidemiological cut-off value. However, the results indicated a general resistance to these three antimicrobials. Multidrug resistance was noted in 57.1% (n/N = 12/21) of the Arcobacter isolates from Tanzania and 45.0% (n/N = 50/111) of those from Ghana. The type of farm (commercial or smallholder) and source of the sample (poultry or livestock) were found to be associated with multi-drug resistance.

CONCLUSIONS

The high levels of MDR Arcobacter detected from farms in both countries call for urgent attention and comprehensive strategies to mitigate the spread of antimicrobial resistance in these pathogens.

Salmonella enterica in farm environments in the Ashanti Region of Ghana

BACKGROUND

Salmonella enterica are important foodborne pathogens and the third leading cause of death among diarrheal infections worldwide. This cross-sectional study investigated the frequency of antibiotic-resistant Salmonella enterica in commercial and smallholder farm environments in the Ashanti Region of Ghana. A total of 1490 environmental samples, comprising 800 (53.7%) soil (from poultry, pigs, sheep, goats and cattle farms), 409 (27.4%) pooled poultry fecal and 281 (18.9%) dust (from poultry farms) samples, were collected from 30 commercial and 64 smallholder farms. All samples were processed using standard culture methods. Isolates were identified by biochemical methods and confirmed using the VITEK 2 System. Antibiotic susceptibility testing was carried out by disk diffusion following the EUCAST guidelines. Serotyping was performed using the Kauffman White Le Minor Scheme.

RESULTS

The overall Salmonella frequency was 6.0% (n/N = 90/1490); the frequency varied according to the type of sample collected and included: 8.9% for dust (n/N = 25/281), 6.5% for soil (n/N = 52/800) and 3.2% for pooled poultry fecal samples (n/N = 13/409). Salmonella was also recovered from commercial farm environments (8.6%, n/N = 68/793) than from smallholder farms (3.2%, n/N = 22/697) (PR = 2.7, CI: 1.7 - 4.4). Thirty-four different Salmonella serovars were identified, the two most common being Rubislaw (27.8%, n/N = 25/90) and Tamale (12.2%, n/N = 11/90). Serovar diversity was highest in strains from soil samples (70.6%, n/N = 24/34) compared to those found in the dust (35.2%, n/N = 12/34) and in fecal samples (29.4%, n/N = 10/34). Salmonella frequency was much higher in the rainy season (8.4%, n/N = 85/1007) than in the dry season (1.0%, n/N = 5/483) (PR = 8.4, 95% CI: 3.3 - 20.0). Approximately 14.4% (n/N = 13/90) of the isolates were resistant to at least one of the tested antimicrobials, with 84.6% (n/N = 11/13) being resistant to multiple antibiotics. All Salmonella Kentucky (n = 5) were resistant to ciprofloxacin.

CONCLUSION

This study showed that farm environments represent an important reservoir for antibiotic-resistant Salmonella, which warrants monitoring and good husbandry practices, especially in commercial farms during the rainy season, to control the spread of this pathogen.

Widespread Multidrug Resistance of Arcobacter butzleri Isolated from Clinical and Food Sources in Central Italy

The Arcobacter genus comprises a group of bacteria widely distributed in different habitats that can be spread throughout the food chain. Fluoroquinolones and aminoglycosides represent the most common antimicrobial agents used for the treatment of Arcobacter infections. However, the increasing trend of the antimicrobial resistance of this pathogen leads to treatment failures. Moreover, the test implementation and interpretation are hindered by the lack of reference protocols and standard interpretive criteria. The purpose of our study was to assess the antibiotic resistance pattern of 17 A. butzleri strains isolated in Central Italy from fresh vegetables, sushi, chicken breast, and clinical human samples to provide new and updated information about the antimicrobial resistance epidemiology of this species. Antimicrobial susceptibility testing was carried out by the European Committee on Antimicrobial Susceptibility Testing (EUCAST)'s disc diffusion method. All the strains were multidrug resistant, with 100% resistance to tetracyclines and cefotaxime (third generation cephalosporins). Some differences were noticed among the strains, according to the isolation source (clinical isolates, food of animal origin, or fresh vegetables), with a higher sensitivity to streptomycin detected only in the strains isolated from fresh vegetables. Our data, together with other epidemiological information at the national or European Union (EU) level, may contribute to developing homogeneous breakpoints. However, the high prevalence of resistance to a wide range of antimicrobial classes makes this microorganism a threat to human health and suggests that its monitoring should be considered by authorities designated for food safety.

Comparison of the Diagnostic Accuracy of Three Real-Time PCR Assays for the Detection of Arcobacter butzleri in Human Stool Samples Targeting Different Genes in a Test Comparison without a Reference Standard

Potential etiological relevance for gastroenteric disorders including diarrhea has been assigned to Arcobacter butzleri. However, standard routine diagnostic algorithms for stool samples of patients with diarrhea are rarely adapted to the detection of this pathogen and so, A. butzleri is likely to go undetected unless it is specifically addressed, e.g., by applying pathogen-specific molecular diagnostic approaches. In the study presented here, we compared three real-time PCR assays targeting the genes hsp60, rpoB/C (both hybridization probe assays) and gyrA (fluorescence resonance energy transfer assay) of A. butzleri in a test comparison without a reference standard using a stool sample collection with a high pretest probability from the Ghanaian endemicity setting. Latent class analysis was applied with the PCR results obtained with a collection of 1495 stool samples showing no signs of PCR inhibition to assess the real-time PCR assays' diagnostic accuracy. Calculated sensitivity and specificity were 93.0% and 96.9% for the hsp60-PCR, 100% and 98.2% for the rpoB/C-PCR, as well as 12.7% and 99.8% for the gyrA-PCR, respectively. The calculated A. butzleri prevalence within the assessed Ghanaian population was 14.7%. As indicated by test results obtained with high-titer spiked samples, cross-reactions of the hsp60-assay and rpoB/C-assay with phylogenetically related species such as A. cryaerophilus can occur but are less likely with phylogenetically more distant species like, e.g., A. lanthieri. In conclusion, the rpoB/C-assay showed the most promising performance characteristics as the only assay with sensitivity >95%, albeit associated with a broad 95%-confidence interval. In addition, this assay showed still-acceptable specificity of >98% in spite of the known cross-reactivity with phylogenetically closely related species such as A. cryaerophilus. If higher certainty is desired, the gyrA-assay with specificity close to 100% can be applied for confirmation testing with samples showing positive rpoB/C-PCR results. However, in case of a negative result in the gyrA-assay, this cannot reliably exclude the detection of A. butzleri in the rpoB/C-assay due to the gyrA-assay's very low sensitivity.

Genomic Characterization of Antibiotic-Resistant Campylobacterales Isolated from Chilean Poultry Meat

Due to the lack of knowledge about Campylobacterales in the Chilean poultry industry, the objective of this research was to know the prevalence, resistance, and genotypes of Campylobacter, Arcobacter and Helicobacter in 382 samples of chicken meat purchased in Valdivia, Chile. The samples were analyzed using three isolation protocols. Resistance to four antibiotics was evaluated by phenotypic methods. Genomic analyses were performed on selected resistant strains to detect resistance determinants and their genotypes. A total of 59.2% of the samples were positive. Arcobacter butzleri (37.4%) was the most prevalent species, followed by Campylobacter jejuni (19.6%), C. coli (11.3%), A. cryaerophilus (3.7%) and A. skirrowii (1.3%). Helicobacter pullorum (14%) was detected by PCR in a subset of samples. Campylobacter jejuni was resistant to ciprofloxacin (37.3%) and tetracycline (20%), while C. coli and A. butzleri were resistant to ciprofloxacin (55.8% and 2.8%), erythromycin (16.3% and 0.7%) and tetracycline (4.7% and 2.8%), respectively. Molecular determinants were consistent with phenotypic resistance. The genotypes of C. jejuni (CC-21, CC-48, CC-49, CC-257, CC-353, CC-443, CC-446 and CC-658) and C. coli (CC-828) coincided with genotypes of Chilean clinical strains. These findings suggest that besides C. jejuni and C. coli, chicken meat could play a role in the transmission of other pathogenic and antibiotic-resistant Campylobacterales.

Putative Role of an ABC Efflux System in Aliarcobacter butzleri Resistance and Virulence

Aliarcobacter butzleri is considered a ubiquitous microorganism and emergent pathogen, for which increasing rates of multidrug resistance have been described. In line with this, the present work aimed to evaluate for the first time the contribution of an ABC efflux system, the YbhFSR, in the resistance and virulence of this bacterium. Following the in silico characterization of the YbhFSR transporter, a mutant strain was constructed by inactivating the gene responsible for ATP-binding. After ensuring that the mutation did not have an impact on bacterial growth, the resistance profile of parental and mutant strains to different antimicrobial agents was evaluated. The results suggest that the efflux pump may influence the resistance to benzalkonium chloride, ethidium bromide, and cadmium, and several other compounds were identified as potential substrates. Regarding the evaluation of the accumulation of ethidium bromide, a slight increase was observed for the mutant strain, demonstrating a potential role of the YbhFSR efflux pump in the extrusion of toxic compounds from A. butzleri. Subsequently, the role of this efflux pump on the A. butzleri known virulence properties was evaluated, but no difference was seen among mutant and parental strains for the motility, biofilm formation ability, susceptibility to oxidative stress, or the ability to adhere and invade Caco-2 cells. However, in contrast to the parental strain, the mutant strain showed a resistance to human serum. Overall, the results support the role of efflux pumps in A. butzleri resistance to antimicrobials, highlighting the particular role of the YbhFSR system.

Genetic characteristics, antimicrobial resistance, and prevalence of Arcobacter spp. isolated from various sources in Shenzhen, China

Arcobacter spp. is a globally emerging zoonotic and foodborne pathogen. However, little is known about its prevalence and antimicrobial resistance in China. To investigate the prevalence of Arcobacter spp. isolated from various sources, 396 samples were collected from human feces, chicken cecum, and food specimens including chicken meat, beef, pork, lettuce, and seafood. Arcobacter spp. was isolated by the membrane filtration method. For 92 strains, the agar dilution method and next-generation sequencing were used to investigate their antimicrobial resistance and to obtain whole genome data, respectively. The virulence factor database (VFDB) was queried to identify virulence genes. ResFinder and the Comprehensive Antibiotic Resistance Database (CARD) were used to predict resistance genes. A phylogenetic tree was constructed using the maximum likelihood (ML) method with core single-nucleotide polymorphisms (SNPs). We found that 27.5% of the samples (n = 109) were positive for Arcobacter spp., comprising Arcobacter butzleri (53.0%), Arcobacter cryaerophilus (39.6%), and Arcobacter skirrowii (7.4%). Chicken meat had the highest prevalence (81.2%), followed by seafood (51.9%), pork (43.3%), beef (36.7%), lettuce (35.5%), chicken cecum (8%), and human fecal samples (0%, 0/159). Antimicrobial susceptibility tests revealed that 51 A. butzleri and 40 A. cryaerophilus strains were resistant to streptomycin (98.1, 70%), clindamycin (94.1, 90%), tetracycline (64.7, 52.5%), azithromycin (43.1%, 15%), nalidixic acid (33.4, 35%), and ciprofloxacin (31.3, 35%) but were susceptible to erythromycin, gentamicin, chloramphenicol, telithromycin, and clindamycin (≤10%). A. skirrowii was sensitive to all experimental antibiotics. The virulence factors tlyA, mviN, cj1349, ciaB, and pldA were carried by all Arcobacter spp. strains at 100%, and the following percentages were cadF (95.7%), iroE (23.9%), hecB (2.2%), hecA, and irgA (1.1%). Only one A. butzleri strain (F061-2G) carried a macrolide resistance gene (ereA). One A. butzleri and one A. cryaerophilus harbored resistance island gene clusters, which were isolated from pork and chicken. Phylogenetic tree analysis revealed that A. butzleri, A. cryaerophilus, and A. skirrowii were separated from each other. To our knowledge, this is the first report of the isolation of Arcobacter spp. from vegetables and seafood in China. The resistance island gene cluster found in pork and chicken meat and the presence of virulence factors could be a potential risk to human health.

Urinary Antibiotics and Dietary Determinants in Adults in Xinjiang, West China

The Xinjiang autonomous region, located in west China, has a unique ethnic structure and a well-developed livestock industry. People in this region have a high risk of exposure to antibiotics, but the exposure level to antibiotics in relation to dietary determinants is unknown. In this study, 18 antibiotics, including four human antibiotics (HAs), four veterinary antibiotics (VAs), and 10 preferred veterinary antibiotics (PVAs) were detected in the urine of approximately half of the 873 adults in Xinjiang, including Han Chinese (24.6%), Hui (25.1%), Uighur (24.6%), and Kazakh (25.7%). Logistic regression was used to analyze the association between antibiotic exposure levels and adult diet and water intake. The detection percentage of antibiotics in the urine of adults in Xinjiang ranged from 0.1% to 30.1%, with a total detection percentage of all antibiotics of 49.8%. HAs, VAs and PVAs were detected in 12.3%, 10.3%, and 40.5%, respectively. Fluoroquinolones were the antibiotics with the highest detection percentage (30.1%) and tetracyclines were the antibiotics with the highest detected concentration (17 ng/mL). Adults who regularly ate pork, consumed fruit daily, and did not prefer a plant-based diet were associated with thiamphenicol, norfloxacin, and fluoroquinolones, respectively. These results indicated that adults in the Xinjiang autonomous region were extensively exposed to multiple antibiotics, and some types of food were potential sources of exposure. Special attention should be paid to the health effects of antibiotic exposure in humans in the future.

Antibiotic-resistant Campylobacter coli and Campylobacter jejuni in commercial and smallholder farm animals in the Asante Akim North Municipality of Ghana

Worldwide, farm animals, in particular poultry, are an important reservoir for Campylobacter spp. However, information on Campylobacter colonization in farm animals in Africa is scarce. Hence, this cross-sectional study determined antibiotic-resistant Campylobacter from both commercial and smallholder farm animals in the Asante Akim North Municipality of Ghana. Fecal samples from poultry and livestock kept by commercial and smallholder farms were collected and analyzed using standard microbiological methods. The overall Campylobacter frequency was 20.3% (n/N = 322/1,585), and frequencies detected were similarly high in isolates from commercial (21.0%, n/N = 169/805) and smallholder (19.6%, n/N = 153/780) farms. Species isolated were C. coli (67.7%, n/N = 218/322) and C. jejuni (32.3%, n/N = 104/322). However, the frequency of C. coli was 2.1 (95% CI: 1.8-2.5) times higher than what was found for C. jejuni. Campylobacter frequencies in the rainy season was 22.2% (n/N = 258/1,160) and 15.1% (n/N = 64/425) in the dry season (prevalence ratio = 1.48, 95% CI: 1.2-1.9). About 1.7% (n/N = 6/322) of the Campylobacter isolates, all from smallholder farms, were susceptible to all antibiotics tested. Multidrug resistance was observed for 4.7% (n/N = 15/322) of the Campylobacter isolates, of which 93.3% (n/N = 14/15) occurred in isolates from commercial farms. This study highlights the need for the implementation of control programs, in commercial farming but also at the smallholder farm level, to formulate clear guidelines aimed at decreasing Campylobacter contamination of meat products and reducing the use of antibiotics in the farming sector.

Prevalence and Characterization of Quinolone Resistance in Campylobacter spp. Isolates in Chicken Livers from Retail Stores in Georgia, USA

ABSTRACT

Campylobacter is a bacterial pathogen that causes human foodborne illnesses worldwide, and outbreaks have been associated with consumption of undercooked chicken livers. The objectives of this study were to compare two PCR assays of 250 Campylobacter isolates for identification to species, to assess antibiotic resistance of the isolates, and to analyze genetic diversity of the quinolone resistance determining regions (QRDRs) of the isolates. A double-blind design was used to identify the species of Campylobacter; 181 (72%) of the isolates were identified as Campylobacter jejuni, and 69 (28%) isolates were identified as Campylobacter coli by both PCR assays. A total of 93 (37.2%) isolates were resistant to at least one antibiotic. Among 88 C. jejuni isolates, 33 (18%) were resistant to nalidixic acid (NAL) and ciprofloxacin (CIP), 25 (14%) were resistant to tetracycline (TET), and 18 (10%) were resistant to NAL and TET. Two C. jejuni isolates were resistant to four of the tested antibiotics, and one isolate was resistant to five antibiotics. Two C. coli isolates were resistant to TET, and two were resistant to NAL, CIP, and TET. The amino acid sequences of the QRDRs for the isolates had eight point mutations and could be classified into 12 groups. Thirty-eight C. jejuni isolates resistant to NAL and CIP had a point mutation at residue 86 (substitution from threonine to isoleucine). However, six isolates without this substitution were resistant to NAL and/or CIP. Ten isolates with a point mutation at residue 86 were susceptible to NAL and CIP. This observation suggests that in addition to the substitution at residue 86 other mechanisms may confer resistance to quinolones. Further studies are needed to elucidate mechanisms for quinolone resistance in Campylobacter. The Campylobacter spp. isolated from chicken livers in this study were resistant to quinolones and other classes of antibiotics.

HIGHLIGHTS

Prevalence and Antibiotic Resistance in Campylobacter spp. Isolated from Humans and Food-Producing Animals in West Africa: A Systematic Review and Meta-Analysis

Campylobacter species are one of the leading causes of gastroenteritis in humans. This review reports on the prevalence and antibiotic resistance data of Campylobacter spp. isolated from humans and food-producing animals in West Africa. A systematic search was carried out in five databases for original articles published between January 2000 and July 2021. Among 791 studies found, 38 original articles from seven (41%) out of the 17 countries in West Africa met the inclusion criteria. For studies conducted in food-producing animals, the overall pooled prevalence of Campylobacter spp. was 34% (95% CI: 25–45). The MDR prevalence was 59% (95% CI: 29–84) and half (50%, 13/26) of the animal studies had samples collected from the market. The human studies recorded a lower pooled prevalence of Campylobacter spp. (10%, 95% CI: 6–17), but a considerably higher rate of MDR prevalence (91%; 95% CI: 67–98). The majority (85%, 11/13) of the human studies took place in a hospital. Campylobacter jejuni and Campylobacter coli were the most common species isolated from both animals and humans. Our findings suggest that Campylobacter spp. is highly prevalent in West Africa. Therefore, improved farm hygiene and ‘One Health’ surveillance systems are needed to reduce transmission.

Prevalence, virulence genes and anti­microbial resistance of Arcobacter isolates from animal meat in Iran

Arcobacter spp. are food-borne and zoonotic entero-pathogens. Obtaining information in relation to antimicrobial resistance helps us for utilisation of an appropriate agent for the treatment of Arcobacter infections. This study aimed to investigate the prevalence, antimicrobial resistance and virulence factors in animal raw meat in Iran. The samples were collected from cattle (n=80), sheep (n=80), goats (n=80), camels (n=80), and buffaloes (n=60) from Khuzestan (n=110), Isfahan (n=80), Gilan (n=110) and Chaharmahal and Bakhtiari (n=80) provinces. Arcobacter isolates of meat samples were isolated, investigated by PCR method. The antibiotic resistance was also investigated. All isolates were screened for 6 virulence genes: cadF, ciaB, cj1349, Mvin, pldA and tlyA by PCR assays. The results showed that the prevalence of Arcobacter species had no significant difference among provinces and animals (P>0.05), so that positive samples were 1.25%, 1.25%, and 0.9% in Isfafhan, Chaharmahal and Bakhtiari, and Gilan, respectively. Virulence genes were observed for A. butzleri species (n=3, 100%). The results showed that Arcobacter spp. were resistant to streptomycin (100%), tetracycline (100%) and vancomycin (100%), but were susceptible to azithromycin (33.33%). In sum, the different regions of the Iran had a relative incidence of 1% for Arcobacter spp. The species showed a resistance of 100% for streptomycin, tetracycline and vancomycin. These findings could help to identify Arcobacter spp. and select the best agent against infection in case of Arcobacter infection in animals.

A review of antimicrobial resistance in imported foods

Antimicrobial resistance is one of the most serious threats to medical science. Food supply is recognized as a potential source of resistant bacteria, leading to the development of surveillance programs targeting primarily poultry, pork, and beef. These programs are limited in scope, not only in the commodities tested, but also in the organisms targeted (Escherichia coli, Salmonella, and Campylobacter); consequently, neither the breadth of food products available nor the organisms that may harbour clinically relevant and (or) mobile resistance genes are identified. Furthermore, there is an inadequate understanding of how international trade in food products contributes to the global dissemination of resistance. This is despite the recognized role of international travel in disseminating antimicrobial-resistant organisms, notably New Delhi metallo-beta-lactamase. An increasing number of studies describing antimicrobial-resistant organisms in a variety of imported foods are summarized in this review.

Antimicrobial Usage in Commercial and Domestic Poultry Farming in Two Communities in the Ashanti Region of Ghana

Poultry farming is a common practice in Ghana. Antibiotics are used, particularly in commercial poultry farming, as growth promoters and to prevent and cure infections. However, there is little information on antimicrobial usage in domestic poultry farming in Ghana. This study aimed to describe antimicrobial usage in commercial and domestic poultry farming. A cross-sectional survey was conducted within the Ashanti region of Ghana including 33 commercial farms and 130 households with domestic poultry farming. The median poultry population on commercial farms was 1500 (IQR: 300–3000) compared with 18 (IQR: 10–25) on domestic farms. The majority (97%, n = 32) of commercial farms used antimicrobials, compared with 43% (n = 56) of the domestic farms. Commercial farmers were 6.1 (CI: 3.2–11.8) times more likely to read and follow instructions on antimicrobials in comparison with domestic poultry keepers. About 11% of domestic and 34% of commercial farmers had received education on antimicrobial usage. None of the commercial farmers used herbal remedies; however, 40% (n/N = 52/130) of domestic farmers administered herbs. The misuse of antimicrobials in domestic poultry production calls for stricter regulations and training to limit the emergence and spread of antimicrobial-resistant bacteria among poultry.

Antibiotic resistance of Escherichia coli and Salmonella spp. strains isolated from healthy poultry farms in the districts of Abidjan and Agnibilékrou (Côte d'Ivoire)

Background and Aim

Antimicrobial resistance (AMR) is a serious challenge to animal and human health worldwide. Therefore, this study aims to determine levels and patterns of AMR of Escherichia coli and Salmonella spp. strains isolated from poultry farms in Côte d'Ivoire.

Materials and Methods

A cross-sectional study was conducted in two districts of Côte d'Ivoire with high poultry production: Abidjan and Agnibilékrou. A total of 231 fecal samples were collected in 124 poultry farms in both districts. Enterobacteria were isolated and tested for susceptibility to 14 antimicrobial agents using the disk-diffusion method.

Results

A total of 212 E. coli and 36 Salmonella strains were isolated. In Abidjan, 139 collected samples generated 101 E. coli and 23 Salmonella strains, whereas in Agnibilékrou, 92 collected samples generated 111 E. coli and 13 Salmonella strains. Variable resistance levels were recorded for the antibiotics tested. The resistance prevalence of E. coli and Salmonella, respectively, was high: Doxycycline (98%/94%), sulfonamide (84%/86%), trimethoprim-sulfamethoxazole (80%/41%), and streptomycin (71%/52%). Average resistance rates were recorded for flumequine (38%/66%), ampicillin (49%/33%), amoxicillin (25%/44%), colistin (26%/2%), chloramphenicol (21%/2%), and gentamicin (4%/47%). The antibiotics least affected by resistance were cefuroxime (4%/5%), ceftriaxone (2%/0.00%), and nitrofurantoin (1%/0.00%).

Conclusion

In this study, it was observed that resistance to important antibiotics is emerging in poultry production in Côte d'Ivoire. Policies promoting the rational use of antibiotics should be implemented to manage antibiotic resistance in animal production.

Highly prevalent multidrug resistance and QRDR mutations in Salmonella isolated from chicken, pork and duck meat in Southern China, 2018-2019

This study was undertaken to investigate the prevalence, serotype distribution and antimicrobial resistance in Salmonella isolated from retail meat in Southern China, and to characterize the major mechanisms that mediate the ciprofloxacin resistance of isolates. High levels of Salmonella contamination were detected in pork (67.0%), duck (50.5%) and chicken (46.2%). Thirty different serotypes were identified among 500 detected Salmonella isolates, as well as significant differences in serotypes between different retail meat samples. Notably, 405 (80.1%) isolates exhibited multidrug resistance (MDR). Meanwhile, we also found that 74 (14.8%) Salmonella isolates were resistant to ciprofloxacin and the major mechanisms underlying this resistance were investigated. The commonest mutations in gyrA S83F (40.5%) and D87N (35.1%), and in parC was T57S (71.6%) and S80I (35.1%). Multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) analysis revealed that the S. Kentucky isolates that were resistant to ciprofloxacin mostly belonged to ST198 (21/23, 91.3%) and PFGE revealed the presence of various genotypes. This study identified a diversity of Salmonella serotypes and a high prevalence of multidrug resistance (MDR) among Salmonella isolated from retail meat in Southern China, which indicates that foodborne Salmonella potentially constitutes a potential food safety risk.

Arcobacter butzleri: Up-to-date taxonomy, ecology, and pathogenicity of an emerging pathogen

Arcobacter butzleri, recently emended to the Aliarcobacter butzleri comb. nov., is an emerging pathogen causing enteritis, severe diarrhea, septicaemia, and bacteraemia in humans and enteritis, stillbirth, and abortion in animals. Since its recognition as emerging pathogen on 2002, advancements have been made in elucidating its pathogenicity and epidemiology, also thanks to advent of genomics, which, moreover, contributed in emending its taxonomy. In this review, we provide an overview of the up-to-date taxonomy, ecology, and pathogenicity of this emerging pathogen. Moreover, the implication of A. butzleri in the safety of foods is pinpointed, and culture-dependent and independent detection, identification, and typing methods as well as strategies to control and prevent the survival and growth of this pathogen are provided.

Prevalence, Antimicrobial Resistance, Virulence Genes and Genetic Diversity of Salmonella Isolated from Retail Duck Meat in Southern China

Salmonella is an important cause of foodborne diseases. This study was undertaken to investigate the prevalence, serotype distribution, antimicrobial resistance, virulence genes, and genetic diversity of Salmonella isolates recovered from fresh duck meat obtained from retail markets in Southern China. In total, 365 samples of fresh duck meat were collected from retail markets in six different cities of Guangdong Province between May 2017 and April 2019. High levels of Salmonella contamination were detected in duck meat (151/365, 41.4%). Twenty-six different Salmonella serotypes were identified: S. Corvallis (n = 25, 16.6%), S. Kentucky (n = 22, 14.6%) and S. Agona (n = 20, 13.3%) were the most prevalent serotypes. All isolates were resistant to at least one antibiotic and 133 (88.1%) isolates exhibited multidrug resistance (MDR). Most (86.1%) Salmonella isolates carried seven classes of virulence-associated genes. This study showed the diversity of Salmonella serotypes and genotypes and the high prevalence of MDR isolates carrying multiple virulence-associated genes among isolates from duck meat obtained from retail markets in Southern China. Isolates from different districts had similar pulsed-field gel electrophoresis (PFGE) patterns indicating that circulating foodborne Salmonella constitutes a potential public health issue across different districts.

Chromosomal and plasmid-mediated fluoroquinolone resistance in human Salmonella enterica infection in Ghana

Background

Salmonella infection poses significant public health threat globally, especially in resource-limited countries. Emergence and spread of antibiotic resistant strains to fluoroquinolones have led to treatment failures and increased mortality in Salmonella infection. However, there is dearth of information regarding mechanisms of resistance to fluoroquinolones in Ghana. This study therefore sought to identify chromosomal mutations and plasmid-mediated resistance as possible mechanisms of fluoroquinolone resistance from clinical isolates in Ghana.

Methods

This was a retrospective study of archived isolates biobanked at Kumasi Centre for Collaborative Research in Tropical Medicine, Ghana. Isolates were obtained from blood, stool and oropharynx samples at two hospitals, between May, 2016 and January, 2018. Salmonella identification was done using standard microbiological protocols and antibiotic susceptibility testing performed by Kirby-Bauer disc diffusion method. Isolates with intermediate susceptibility and/or resistance to nalidixic acid and/or ciprofloxacin were selected and examined for chromosomal mutations by Sanger sequencing and plasmid-mediated resistance by PCR.

Results

Of 133 biobanked isolates cultured, 68 (51.1%) and 16 (12%) were identified as Salmonella Typhi and non-typhoidal Salmonella (NTS), respectively. Sequence analysis of gyrA gene revealed the presence of 5 different nonsynonymous mutations, with the most frequent mutation (Ile203Ser) occurring in 12 out of 13 isolates tested. Gyrase B (gyrB) gene had 1 nonsynonymous mutation in 3 out of 13 isolates, substituting phenylalanine with leucine at codon 601 (Phe601Leu). No mutation was observed in parC and parE genes. Two NTS isolates were found to harbour qnrS plasmid-mediated resistant gene of molecular size 550 bp with high ciprofloxacin MIC of 0.5 μg/ml.

Conclusion

This study reports for the first time in Ghana plasmid-mediated fluoroquinolone resistant gene qnrS in Salmonella clinical isolates. Nonsynonymous mutations of gyrA and gyrB genes likely to confer Salmonella reduced susceptibility to ciprofloxacin were also reported.