Molecular epidemiology and antimicrobial susceptibility of human Clostridium difficile isolates from a single institution in Northern China

Recent development and fighting strategies for lincosamide antibiotic resistance

SUMMARYLincosamides constitute an important class of antibiotics used against a wide range of pathogens, including methicillin-resistant Staphylococcus aureus. However, due to the misuse of lincosamide and co-selection pressure, the resistance to lincosamide has become a serious concern. It is urgently needed to carefully understand the phenomenon and mechanism of lincosamide resistance to effectively prevent and control lincosamide resistance. To date, six mobile lincosamide resistance classes, including lnu, cfr, erm, vga, lsa, and sal, have been identified. These lincosamide resistance genes are frequently found on mobile genetic elements (MGEs), such as plasmids, transposons, integrative and conjugative elements, genomic islands, and prophages. Additionally, MGEs harbor the genes that confer resistance not only to antimicrobial agents of other classes but also to metals and biocides. The ultimate purpose of discovering and summarizing bacterial resistance is to prevent, control, and combat resistance effectively. This review highlights four promising strategies, including chemical modification of antibiotics, the development of antimicrobial peptides, the initiation of bacterial self-destruct program, and antimicrobial stewardship, to fight against resistance and safeguard global health.

Antimicrobial Resistance and Associated Risk Factors for Clostridium difficile in Patients Attending Tertiary Care Settings

To determine the incidence of antimicrobial-resistant emerging pathogens, Clostridium difficile, and its associated risk factors in tertiary care setups of Pakistan. This cross-sectional prospective study was conducted from January 2019 to December 2020, to determine the prevalence and antimicrobial resistance patterns of C. difficile strains isolated from 450 stool specimens of patients suffering from diarrhea hospitalized in tertiary care hospitals in Peshawar, Pakistan. The stool samples of the patients were processed for culture and detection of toxin A and toxin B by enzyme-linked immunosorbent assay (ELISA) and tpi PCR. The drug sensitivity test was performed for antibiotics including ampicillin, cefixime, cefepime, amoxicillin, nalidixic acid, sulpha/TMP (SXT), chloramphenicol, metronidazole, vancomycin, ciprofloxacin, levofloxacin, and imipenem. Of 450 stool specimens, 108 (24%) were positive for C. difficile by stool culture, whereas 115 (25.5%) were only positive for C. difficile toxins based on ELISA and PCR (128 (28.6%). Of 108, 90.7% (n = 98) isolates were resistant to one antibiotic, and 90 (83.4%) were resistant to three or more antimicrobials. The highest resistance rates were found against penicillin (83.3%) followed by amoxicillin (70%), nalidixic acid (61%), and metronidazole (38%), and the lowest resistance was found against vancomycin (6.4%) and imipenem (3.7%). CDI was statistically significantly correlated with increased age, use of antibiotics, abdominal surgeries, use of proton pump inhibitors and H2a, and presence of comorbidities. The high frequency of C. difficile in Peshawar, Pakistan, indicates that CDI is an important nosocomial infection in different hospitals. The results will be helpful for clinicians to redesign control and therapeutic strategies in hospitals.

Genotypic and phenotypic antimicrobial resistance of Irish Clostridioides difficile isolates, 2022

OBJECTIVES

Infection with Clostridioides difficile (C. difficile) usually occurs after antibiotic treatment for other infections and can cause gastro-intestinal disorders of variable severity. C. difficile can be resistant to a wide spectrum of antimicrobials. Detection of antimicrobial resistance (AMR) is important to direct optimal treatment and surveillance of AMR patterns in the overall population. Correlation between genotypic markers and phenotypic AMR is not yet well defined. The aim for this study is to assess whether and to what extent genotypic determinants of AMR correlate with phenotypic resistance.

METHODS

99 C. difficile isolates were phenotypically characterized for resistance to eight antibiotics using Sensititre plates or E-tests. Their genomes were screened for genetic markers of resistance. Accuracy, sensitivity, specificity, positive and negative predictive values were calculated.

RESULTS

We found high rates of resistance (>50%) to cefoxitin and clindamycin, intermediate rates of resistance (10% - 50%) to moxifloxacin and tetracycline and low rates of resistance (<10%) to imipenem, metronidazole, vancomycin, and rifampicin. For moxifloxacin, tetracycline, and clindamycin, we found a good correlation between genotypic and phenotypic AMR, with an overall accuracy of 96% (95% CI 90%-100%), 78% (95% CI 68%-86%) and 86% (95% CI 77%-92%) respectively. For the other five antibiotics, accurate estimates on the correlation could not be made.

CONCLUSION

Our results suggest that for moxifloxacin, tetracycline and clindamycin, phenotypic resistance in C. difficile can be predicted by genetic indicators and used for public health purposes. However, for the other five antibiotics, the model is not accurate and further development is necessary.

Update on Commonly Used Molecular Typing Methods for Clostridioides difficile

This review aims to provide a comprehensive overview of the significant Clostridioides difficile molecular typing techniques currently employed in research and medical communities. The main objectives of this review are to describe the key molecular typing methods utilized in C. difficile studies and to highlight the epidemiological characteristics of the most prevalent strains on a global scale. Geographically distinct regions exhibit distinct strain types of C. difficile, with notable concordance observed among various typing methodologies. The advantages that next-generation sequencing (NGS) offers has changed epidemiology research, enabling high-resolution genomic analyses of this pathogen. NGS platforms offer an unprecedented opportunity to explore the genetic intricacies and evolutionary trajectories of C. difficile strains. It is relevant to acknowledge that novel routes of transmission are continually being unveiled and warrant further investigation, particularly in the context of zoonotic implications and environmental contamination.

Molecular epidemiology, antimicrobial susceptibility, and toxin production of clinical Clostridioides difficile isolates from a teaching hospital in Northern China

To grasp the epidemiological trend and drug resistance mechanisms of Clostridioides difficile (C. diff) in Beijing, 302 C. diff isolates were obtained from patients with diarrhea. The sequence types (STs) from mainstream strains were all susceptible to metronidazole, vancomycin, piperacillin/tazobactam, meropenem, and tigecycline but almost resistant to ciprofloxacin and clindamycin. The missense mutation of GyrA/GyrB and RpoB resulted in fluoroquinolone and rifamycin resistance, respectively. Toxigenic strains from clade IV were likely to be missed due to the deficiency of tcdA gene. Four tcdC genotypes were first detected in strains from clade III and IV. The truncating mutation of TcdC disabled its function working as a toxin suppressor. In conclusion, the molecular epidemiology of C. diff in Beijing is different from other regions of China. The antimicrobial resistance patterns and toxin-producing abilities of strains with different STs varied greatly, which suggests that continuous surveillance and control are meaningful and urgent.

Prevalence and molecular characterization of Clostridioides difficile infection in China over the past 5 years: a systematic review and meta-analysis

OBJECTIVES

The aim of this study was to provide an overview of the prevalence and molecular characteristics of Clostridioides difficile infection (CDI) in China in the past 5 years.

METHODS

A systematic literature review was conducted according to the preferred reporting items for systematic reviews and meta-analyses guidelines. Nine databases were searched for relevant studies published between January 2017 and February 2022. The Joanna Briggs Institute critical appraisal tool was used to assess the quality of included studies, and R software version 4.1.3 was used for data analysis. Funnel plots and Egger regression tests were also performed to assess publication bias.

RESULTS

A total of 50 studies were included in the analysis. The pooled prevalence of CDI in China was 11.4% (2696/26,852). The main circulating C. difficile strains in southern China were ST54, ST3, and ST37, consistent with the overall situation in China. However, the most prevalent genotype in northern China was ST2, which was previously underappreciated.

CONCLUSION

Based on our findings, increased awareness and management of CDI is necessary to reduce the prevalence of CDI in China.

Antibiotic Resistance Profile of RT 027/176 Versus Other Clostridioides difficile Isolates in Silesia, Southern Poland

Clostridioides difficile is an important health care-associated pathogen. The aim of this study was to analyze the antibiotic susceptibility of C. difficile isolates from feces of patients from 13 hospitals in Silesia, Poland. The incidence of CDI per 100.000 people in Silesia in 2018−2019 was higher than the average in Poland (39.3−38.7 vs. 30.2−29.5, respectively). The incidence doubled from 26.4 in 2020 to 55.1 in 2021. Two hundred and thirty stool samples tested positive for GDH (glutamate dehydrogenase) and toxins were cultured anaerobically for C. difficile. The isolates were characterized, typed, and tested for susceptibility to 11 antibiotics by E-test (EUCAST, 2021). The genes of toxins A/B and binary were detected by mPCR. Of 215 isolates, 166 (77.2%) were classified as RT 027 and 6 (2.8%) as related RT 176. Resistance to ciprofloxacin (96.7%), moxifloxacin (79.1%), imipenem (78.1%), penicillin (67%), and rifampicin (40.5%) was found. The ermB gene was detected in 79 (36.7%) strains. Multidrug resistance (MDR) was confirmed in 50 (23.3%) strains of RT 027 (94%). We concluded that a high prevalence of MDR among hypervirulent RT 027/176 C. difficile was found in the Silesian region of Poland, emphasizing the need to enhance regional infection control on CDI and antibiotic stewardships.

Antimicrobial resistance surveillance of Clostridioides difficile in Australia, 2015-18

BACKGROUND

Clostridioides difficile was listed as an urgent antimicrobial resistance (AMR) threat in a report by the CDC in 2019. AMR drives the evolution of C. difficile and facilitates its emergence and spread. The C. difficile Antimicrobial Resistance Surveillance (CDARS) study is nationwide longitudinal surveillance of C. difficile infection (CDI) in Australia.

OBJECTIVES

To determine the antimicrobial susceptibility of C. difficile isolated in Australia between 2015 and 2018.

METHODS

A total of 1091 strains of C. difficile were collected over a 3 year period by a network of 10 diagnostic microbiology laboratories in five Australian states. These strains were tested for their susceptibility to nine antimicrobials using the CLSI agar incorporation method.

RESULTS

All strains were susceptible to metronidazole, fidaxomicin, rifaximin and amoxicillin/clavulanate and low numbers of resistant strains were observed for meropenem (0.1%; 1/1091), moxifloxacin (3.5%; 38/1091) and vancomycin (5.7%; 62/1091). Resistance to clindamycin was common (85.2%; 929/1091), followed by resistance to ceftriaxone (18.8%; 205/1091). The in vitro activity of fidaxomicin [geometric mean MIC (GM) = 0.101 mg/L] was superior to that of vancomycin (1.700 mg/L) and metronidazole (0.229 mg/L). The prevalence of MDR C. difficile, as defined by resistance to ≥3 antimicrobial classes, was low (1.7%; 19/1091).

CONCLUSIONS

The majority of C. difficile isolated in Australia did not show reduced susceptibility to antimicrobials recommended for treatment of CDI (vancomycin, metronidazole and fidaxomicin). Resistance to carbapenems and fluoroquinolones was low and MDR was uncommon; however, clindamycin resistance was frequent. One fluoroquinolone-resistant ribotype 027 strain was detected.

Antimicrobial resistance in Clostridioides (Clostridium) difficile derived from humans: a systematic review and meta-analysis

Background

Clostridioides (Clostridium) difficile is an important pathogen of healthcare- associated diarrhea, however, an increase in the occurrence of C. difficile infection (CDI) outside hospital settings has been reported. The accumulation of antimicrobial resistance in C. difficile can increase the risk of CDI development and/or its spread. The limited number of antimicrobials for the treatment of CDI is matter of some concern.

Objectives

In order to summarize the data on antimicrobial resistance to C. difficile derived from humans, a systematic review and meta-analysis were performed.

Methods

We searched five bibliographic databases: (MEDLINE [PubMed], Scopus, Embase, Cochrane Library and Web of Science) for studies that focused on antimicrobial susceptibility testing in C. difficile and were published between 1992 and 2019. The weighted pooled resistance (WPR) for each antimicrobial agent was calculated using a random- effects model.

Results

A total of 111 studies were included. The WPR for metronidazole and vancomycin was 1.0% (95% CI 0–3%) and 1% (95% CI 0–2%) for the breakpoint > 2 mg/L and 0% (95% CI 0%) for breakpoint ≥32 μg/ml. Rifampin and tigecycline had a WPRs of 37.0% (95% CI 18–58%) and 1% (95% CI 0–3%), respectively. The WPRs for the other antimicrobials were as follows: ciprofloxacin 95% (95% CI 85–100%), moxifloxacin 32% (95% CI 25–40%), clindamycin 59% (95% CI 53–65%), amoxicillin/clavulanate 0% (0–0%), piperacillin/tazobactam 0% (0–0%) and ceftriaxone 47% (95% CI 29–65%). Tetracycline had a WPR 20% (95% CI 14–27%) and meropenem showed 0% (95% CI 0–1%); resistance to fidaxomicin was reported in one isolate (0.08%).

Conclusion

Resistance to metronidazole, vancomycin, fidaxomicin, meropenem and piperacillin/tazobactam is reported rarely. From the alternative CDI drug treatments, tigecycline had a lower resistance rate than rifampin. The high-risk antimicrobials for CDI development showed a high level of resistance, the highest was seen in the second generation of fluoroquinolones and clindamycin; amoxicillin/clavulanate showed almost no resistance. Tetracycline resistance was present in one fifth of human clinical C. difficile isolates.

Colonization of Toxigenic Clostridium difficile Among Intensive Care Unit Patients: A Multi-Centre Cross-Sectional Study

Background:Clostridium difficile (CD) is a major cause of healthcare-associated infections and antibiotic-associated diarrhea in hospitalized patients worldwide. Carriers of toxigenic CD (tCD) have a higher risk of developing CD infections and can transmit CD to the environment and susceptible patients. However, little is known regarding the carriers and transmission of tCD in China.

Methods: A multi-center cross-sectional study of tCD colonization (tCDC) was conducted from October 24 to 31, 2014, at 33 hospitals in Shanghai, China. Rectal swabs or stool samples were collected and tested, and the clinical and demographic status, epidemiological data, and blood parameters of 531 participants were recorded. The status of tCDC was defined by a positive result on the nucleic acid amplification test for the tcdA (toxin A), tcdB (toxin B), and cdtAB (toxin CDT) genes after positive bacterial culture.

Results: The overall prevalence of CD colonization (CDC) was 19.02%, tCDC accounted for 92.08%, and A+B+CDT– was the dominant genotype (87.13%). The CD infection (CDI) prevalence was 1.51%. Potential tCDC-associated factors were admission to secondary grade hospitals, a body mass index <18.5, hospitalization during the previous 30 days, underlying diseases (including hypertension, diabetes mellitus, coronary heart disease, and respiratory failure), diarrhea during the previous 7 days, and exposure to fluoroquinolones or lansoprazole.

Conclusions: This study reveals the prevalence of CDC and tCDC in Shanghai, elucidates several associated factors, contributes to the awareness of the current epidemiology in parts of eastern China and provides new insights for further study and infection control practices.

Molecular Epidemiology and Risk Factors of Clostridium difficile ST81 Infection in a Teaching Hospital in Eastern China

BACKGROUND

The prevalence of Clostridium difficile causes an increased morbidity and mortality of inpatients, especially in Europe and North America, while data on C. difficile infection (CDI) are limited in China.

METHODS

From September 2014 to August 2019, 562 C. difficile isolates were collected from patients and screened for toxin genes. Multilocus sequence typing (MLST) and antimicrobial susceptibility tests by E-test and agar dilution method were performed. A case group composed of patients infected with sequence type (ST) 81 C. difficile was compared to the non-ST81 infection group and non CDI diarrhea patients for risk factor and outcome analyses.

RESULTS

The incidence of inpatients with CDI was 7.06 cases per 10,000 patient-days. Of the 562 C. difficile isolates, ST81(22.78%) was the predominant clone over this period, followed by ST54 (11.21%), ST3 (9.61%), and ST2 (8.72%). Toxin genotype tcdA+tcdB+cdt- accounted for 50.18% of all strains, while 29.54% were tcdA-tcdB+cdt- genotypes. Overall, no isolate was resistant to vancomycin, teicoplanin or daptomycin, and resistance rates to meropenem gradually decreased during these years. Although several metronidazole-resistant strains were isolated in this study, the MIC values decreased during this period. Resistance rates to moxifloxacin and clindamycin remained higher than those to the other antibiotics. Among CDI inpatients, longer hospitalization, usage of prednisolone, suffering from chronic kidney disease or connective tissue diseases and admission to emergency ward 2 or emergency ICU were significant risk factors for ST81 clone infection. All-cause mortality of these CDI patients was 4.92%(n=18), while the recurrent cases accounted for 5.74%(n=21). The 60-day mortality of ST81-CDI was significantly higher than non-ST81 infected group, while ST81 also accounted for most of the recurrent CDI cases.

CONCLUSION

This study revealed the molecular epidemiology and risk factors for the dominant C. difficile ST81 genotype infection in eastern China. Continuous and stringent surveillance on the emerging ST81 genotype needs to be initiated.

High Prevalence of Genetically Related Clostridium Difficile Strains at a Single Hemato-Oncology Ward Over 10 Years

Aims: Clostridium difficile (C. difficile) infection (CDI) is the main cause of healthcare-associated infectious diarrhea. We used whole-genome sequencing (WGS) to measure the prevalence and genetic variability of C. difficile at a single hemato-oncology ward over a 10 year period. Methods: Between 2008 and 2018, 2077 stool samples were obtained from diarrheal patients hospitalized at the Department of Lymphoma; of these, 618 were positive for toxin A/B. 140 isolates were then subjected to WGS on Ion Torrent PGM sequencer. Results: 36 and 104 isolates were recovered from 36 to 46 patients with single and multiple CDIs, respectively. Of these, 131 strains were toxigenic. Toxin gene profiles tcdA(+);tcdB(+);cdtA/cdtB(+) and tcdA(+);tcdB(+);cdtA/cdtB(-) were identified in 122 and nine strains, respectively. No isolates showed reduced susceptibility to metronidazole and vancomycin. All tested strains were resistant to ciprofloxacin, and 72.9, 42.9, and 72.9% of strains were resistant to erythromycin, clindamycin, or moxifloxacin, respectively. Multi-locus sequence typing (MLST) identified 23 distinct sequence types (STs) and two unidentified strains. Strains ST1 and ST42 represented 31 and 30.1% of all strains tested, respectively. However, while ST1 was detected across nearly all years studied, ST42 was detected only from 2009 to 2011. Conclusion: The high proportion of infected patients in 2008-2011 may be explained by the predominance of more transmissible and virulent C. difficile strains. Although this retrospective study was not designed to define outbreaks of C. difficile, the finding that most isolates exhibited high levels of genetic relatedness suggests nosocomial acquisition.

Epidemiology and virulence-associated genes of Clostridioides difficile isolates and factors associated with toxin EIA results at a university hospital in Japan

Introduction

Clostridioides difficile is one of the most important nosocomial pathogens; however, reports regarding its clinical and molecular characteristics from Japan are scarce.

Aims

We studied the multilocus sequence typing (MLST)-based epidemiology and virulence-associated genes of isolates and the clinical backgrounds of patients from whom the isolates had been recovered.

Methods

A total of 105 stool samples tested in a C. difficile toxin enzyme immune assay (EIA) were analysed at the University of Tokyo Hospital from March 2013 to July 2014. PCR for MLST and the virulence-associated genes tcdA, tcdB, cdtA, cdtB and tcdC was performed on C. difficile isolates meeting our inclusion criteria following retrospective review of medical records. EIA-positive and EIA-negative groups with toxigenic strains underwent clinical and molecular background comparison.

Results

The toxigenic strains ST17, ST81, ST2, ST54, ST8, ST3, ST37 and ST53 and the non-toxigenic strains ST109, ST15 and ST100 were frequently recovered. The prevalence rate of tcdA-negative ST81 and ST37, endemic in China and Korea, was higher (11.4%) than that reported in North America and Europe, and hypervirulent ST1(RT027) and ST11(RT078) strains that occur in North America and Europe were not recovered. The linkage between the EIA results and cdt A/B positivity, tcdC deletion, or tcdA variation was absent among toxigenic strains. Compared with the 38 EIA-negative cases, the 36 EIA-positive cases showed that the patients in EIA-positive cases were older and more frequently had chronic kidney disease, as well as a history of beta-lactam use and proton pump inhibitor therapy.

Conclusion

In Japan, the prevalence rates for tcdA-negative strains are high, whereas the cdtA/B-positive strains are rare. EIA positivity is linked to older age, chronic kidney disease and the use of beta-lactams and proton pump inhibitors.

Hypervirulent clade 2, ribotype 019/sequence type 67 Clostridioides difficile strain from Japan

Background

Clostridioides difficile ribotype (RT) 019/sequence type (ST) 67 strains belong to a hypervirulent lineage closely related to RT027/ST1; however, limited data are available for hypervirulent clade 2 lineages in Japan. Herein, we report the draft genome of a C. difficile strain B18-123 belonging to clade 2, RT019/ST67 for the first time in Japan.

Results

The pathogenicity locus carried by B18-123 (19.6 kb) showed higher homology (97.29% nucleotide identity) with strain R20291 (RT027/ST1) than the reference strain 630 (RT012/ST54), and B18-123 harbored 8-nucleotide substitutions in tcdC. However, it did not contain an 18-base pair (bp) deletion or a single-bp deletion at position 117 in tcdC, which was identified in the previous strain R20291. A cytotoxicity assay revealed similar cytotoxicity levels between strains B18-123 and ATCC BAA-1870 (RT027/ST1). The B18-123 strain was found to be susceptible to metronidazole and vancomycin.

Conclusion

Our findings contribute to the further understanding of the characteristics of hypervirulent clade 2 including RT019/ST67 lineages.

Antibiotic resistance of clinical isolates of Clostridioides difficile in China and its association with geographical regions and patient age

It is known that antibiotic usage is associated with the development of Clostridioides difficile infection (CDI), especially clindamycin, third-generation cephalosporins, and fuoroquinolones. Antibiotic resistance rates to many antibiotics varies a lot by study. We performed a study focused on antibiotic resistance in clinical isolates of C. difficile from more widespread geographic regions across China. Of 319 C. difficile isolates tested against 11 antibiotics, 313 (98.1%) were resistant to at least one antibiotic. The highest rate of resistance was to ciprofloxacin, clindamycin, and erythromycin across all age groups, similar to previous studies. However, all isolates were susceptible to metronidazole and vancomycin. Overall the resistance rate to tested antibiotics was lower than other reports in China except for chloramphenicol and meropenem. Genotype ST37/RT017 in clade 4 was resistant to more antibiotics than other types. Unexpectedly, RT078 isolates in this study were susceptible to almost all tested antibiotics. In addition, the proportion of multi-drug resistant (MDR) isolates observed (17%) in this study was much lower than several European studies (up to 55%) and a previous study in China (78%). Although isolates from patients aged between 65 and 85 were more resistant to antibiotics in comparison to other age groups, MDR isolates were still detected in children below 2-years of age. The highest percentage of MDR isolates was determined in South China, an area that is most developed economically. The clade 4, RT017 (ST37) has been associated with outbreaks in Europe and North America and is responsible for most C. difficile infections (CDIs) in Asia. In addition, RT017 is often clindamycin and fluoroquinolone resistant. This study provided a relatively comprehensive description of antibiotic resistance of C. difficile in China, and further elucidates the epidemiology and antibiotic resistance of clinical isolates of C. difficile in China at a national level.

Integrated genomic epidemiology and phenotypic profiling of Clostridium difficile across intra-hospital and community populations in Colombia

Clostridium difficile, the causal agent of antibiotic-associated diarrhea, has a complex epidemiology poorly studied in Latin America. We performed a robust genomic and phenotypic profiling of 53 C. difficile clinical isolates established from diarrheal samples from either intrahospital (IH) or community (CO) populations in central Colombia. In vitro tests were conducted to evaluate the cytopathic effect, the minimum inhibitory concentration of ten antimicrobial agents, the sporulation efficiency and the colony forming ability. Eleven different sequence types (STs) were found, the majority present individually in each sample, however in three samples two different STs were isolated. Interestingly, CO patients were infected with STs associated with hypervirulent strains (ST-1 in Clade-2). Three coexistence events (two STs simultaneously detected in the same sample) were observed always involving ST-8 from Clade-1. A total of 2,502 genes were present in 99% of the isolates with 95% of identity or more, it represents a core genome of 28.6% of the 8,735 total genes identified in the set of genomes. A high cytopathic effect was observed for the isolates positive for the two main toxins but negative for binary toxin (TcdA+/TcdB+/CDT- toxin production type), found only in Clade-1. Molecular markers conferring resistance to fluoroquinolones (cdeA and gyrA) and to sulfonamides (folP) were the most frequent in the analyzed genomes. In addition, 15 other markers were found mostly in Clade-2 isolates. These results highlight the regional differences that C. difficile isolates display, being in this case the CO isolates the ones having a greater number of accessory genes and virulence-associated factors.

Clostridium difficile in Asia: Opportunities for One Health Management

Clostridium difficile is a ubiquitous spore-forming bacterium which causes toxin-mediated diarrhoea and colitis in people whose gut microflora has been depleted by antimicrobial use, so it is a predominantly healthcare-associated disease. However, there are many One Health implications to C. difficile, given high colonisation rates in food production animals, contamination of outdoor environments by use of contaminated animal manure, increasing incidence of community-associated C. difficile infection (CDI), and demonstration of clonal groups of C. difficile shared between human clinical cases and food animals. In Asia, the epidemiology of CDI is not well understood given poor testing practices in many countries. The growing middle-class populations of Asia are presenting increasing demands for meat, thus production farming, particularly of pigs, chicken and cattle, is rapidly expanding in Asian countries. Few reports on C. difficile colonisation among production animals in Asia exist, but those that do show high prevalence rates, and possible importation of European strains of C. difficile like ribotype 078. This review summarises our current understanding of the One Health aspects of the epidemiology of CDI in Asia.