Epidemiology and characteristics of antimicrobial resistance in China

Probing antimicrobial synergy by novel lipopeptides paired with antibiotics

Antimicrobial resistance (AMR) is fast becoming a major global challenge in both hospital and community settings as many current antibiotics and treatment processes are under the threat of being rendered less effective or ineffective. Synergistic combination of an antibiotic and an aiding agent with a different set of properties provides an important but largely unexploited option to 'repurpose' existing biomaterial's space while addressing issues of potency, spectrum, toxicity and resistance in early stages of antimicrobial drug discovery. This work explores how to combine tetracycline/minocycline (TC/MC) with a broad-spectrum antimicrobial lipopeptide that has been designed to improve the efficiency of membrane targeting and intramembrane accumulation, thereby enhancing antimicrobial efficacy. Experimental measurements of fractional inhibition concentration index (FICI) were undertaken from binary antibiotic-lipopeptide combinations. Most FICI values were found to be lower than 0.5 against both Gram-positive and Gram-negative bacterial strains studied including 3 AMR strains, revealing strong synergetic effects via favorable membrane-lytic interactions. The antimicrobial actions of this type of binary combinations are featured by the fast time-killing and high TC/MC uptake, benefited from effective membrane-lytic disruptions by the lipopeptide. This study thus provides an important mechanistic understanding of the combined antibiotic-lipopeptide approach to improve the therapeutic potential of conventional antibiotics by illustrating how amphiphilic lipopeptide-antibiotic combinations interact with biological membranes, providing a promising alternative to combat AMR through rational design of lipopeptide as an aiding agent.

Subspecies typing on the example of klebsiella pneumoniae isolated from patients with pulmonary tuberculosis

OBJECTIVE

Aim: The purpose of this study was to evaluate sub-species typing by matrix-activated laser desorption/ionisation mass spectrometry on the example of Klebsiella pneumoniae isolated from patients with pulmonary tuberculosis in Karaganda region..

PATIENTS AND METHODS

Materials and Methods: This study evaluated the potential of MALDI-TOF MS for epidemiological identification of Klebsiella pneumoniae isolated from pulmonary tuberculosis patients in Karaganda region. A total of 47 strains of Klebsiella pneumoniae obtained between 2015 and 2019 were typed. Mass spectra were taken using Microflex LT MALDI-TOF (Bruker) according to standard procedure.

RESULTS

Results: As a result, MALDI-TOF evaluation of subspecies typing on the example of Klebsiella pneumoniae isolated from patients with pulmonary tuberculosis in Karaganda region, predominantly showed the diversity of isolates, indicating their out-of-hospital nature. Based on all available information, including facts, sources, and experimental results, it can be reasonably concluded that the current study of Klebsiella pneumoniae does not provide a complete picture of the epidemiology of this microorganism.

CONCLUSION

Conclusions: The current study provided a limited opportunity to investigate the genetic structure and diversity of Klebsiella pneumoniae subspecies more accurately. The findings suggest that the time-of-flight laser-ionisation ablation mass spectrometry method with magnetic focusing is more likely to detect differences in external characteristics between individual specimens of the same species than internal genetic variation in the microorganisms under study. The practical relevance of this study is to inform the development of more effective infection control strategies in clinical practice and infection control.

ESKAPE in China: epidemiology and characteristics of antibiotic resistance

The escalation of antibiotic resistance and the diminishing antimicrobial pipeline have emerged as significant threats to public health. The ESKAPE pathogens - Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp. - were initially identified as critical multidrug-resistant bacteria, demanding urgently effective therapies. Despite the introduction of various new antibiotics and antibiotic adjuvants, such as innovative β-lactamase inhibitors, these organisms continue to pose substantial therapeutic challenges. People's Republic of China, as a country facing a severe bacterial resistance situation, has undergone a series of changes and findings in recent years in terms of the prevalence, transmission characteristics and resistance mechanisms of antibiotic resistant bacteria. The increasing levels of population mobility have not only shaped the unique characteristics of antibiotic resistance prevalence and transmission within People's Republic of China but have also indirectly reflected global patterns of antibiotic-resistant dissemination. What's more, as a vast nation, People's Republic of China exhibits significant variations in the levels of antibiotic resistance and the prevalence characteristics of antibiotic resistant bacteria across different provinces and regions. In this review, we examine the current epidemiology and characteristics of this important group of bacterial pathogens, delving into relevant mechanisms of resistance to recently introduced antibiotics that impact their clinical utility in China.

Prevalence and molecular characterization of multi-resistant Escherichia coli isolates from clinical bovine mastitis in China

Different antibiotics are used to treat mastitis in dairy cows that is caused by Escherichia coli (E. coli). Antimicrobial resistance in food-producing animals in China has been monitored since 2000. Surveillance data have shown that the prevalence of multiresistant E. coli in animals has increased significantly. This study aimed to investigate the occurrence and molecular characteristics of resistance determinants in E. coli strains (n = 105) obtained from lactating cows with clinical bovine mastitis (CBM) in China. A total of 220 cows with clinical mastitis, which has swollen mammary udder with reduced and red or gangrenous milk, were selected from 5000 cows. The results showed 94.3% of the isolates were recognized as multidrug resistant. The isolates (30.5%) were positive for the class I integrase gene along with seven gene cassettes that were accountable for resistance to trimethoprim resistance (dfrA17, dfr2d and dfrA1), aminoglycosides resistance (aadA1 and aadA5) and chloramphenicol resistance (catB3 and catB2), respectively. The blaTEM gene was present in all the isolates, and these carried the blaCTX gene. A double mutation in gyrA (i.e., Ser83Leu and Asp87Asn) was observed in all fluoroquinolone-resistant isolates. In total, nine fluoroquinolone-resistant E. coli isolates were identified with five different types of mutations in parC. In four (44.4%) isolates, Ser458Ala was present in parE, and in all nine (9/9) fluoroquinolone-resistant isolates, Pro385Ala was present in gyrB. Meanwhile, fluoroquinolone was observed as highly resistant, especially in isolates with gyrA and parC mutations. In summary, the findings of this research recognize the fluoroquinolone resistance mechanism and disclose integron prevalence and ESBLs in E. coli isolates from lactating cattle with CBM.

MAPRS: An intelligent approach for post-prescription review based on multi-label learning

Antimicrobial resistance (AMR) is a major threat to public health worldwide. It is a promising way to improve appropriate prescription by the review and stewardship of antimicrobials, and Post-Prescription Review (PPR) is currently the main tool used in hospitals. Existing methods of PPR typically focus on the dichotomy of antimicrobial prescription based on binary classification which, however, is usually a multi-label classification problem. Moreover, previous research did not explain the causes beneath the inappropriate antimicrobial used in the clinical setting, which could be practically important for problem location and decision improvement. In this paper, we collected antimicrobial prescriptions and related data from clean surgery in a hospital in northeastern China, and proposed a Multi-label Antimicrobial Post-Prescription Review System (MAPRS). MAPRS first uses NLP techniques to process unstructured data in prescriptions and explores the value of clinical record text for solving medical problems. Then, Classifier Chains are used to deal with multi-label problems and fused with machine learning algorithms to construct a classifier. At last, a SHAP explanation module is introduced to explain the inappropriate prescriptions. The experimental results show that MAPRS could achieve great performance in a challenging six-category multi-label task, with a subset accuracy of 90.7 % and an average AUROC of 94.3 %. Our results can help hospitals to perform intelligent prescription review and improve the antimicrobial stewardship.

A study of antibiotic resistance pattern of clinical bacterial pathogens isolated from patients in a tertiary care hospital

We investigated antibiotic resistance pattern in clinical bacterial pathogens isolated from in-patients and out-patients, and compared it with non-clinical bacterial isolates. 475 bacterial strains isolated from patients were examined for antibiotic resistance. Staphylococcus spp. (148; 31.1%) were found to be the most prevalent, followed by Klebsiella pneumoniae (135; 28.4%), Escherichia coli (74; 15.5%), Pseudomonas aeruginosa (65; 13.6%), Enterobacter spp. (28; 5.8%), and Acinetobacter spp. (25; 5.2%). Drug-resistant bacteria isolated were extended spectrum-β-lactamase K. pneumoniae (8.8%), E. coli (20%), metallo-β-lactamase P. aeruginosa (14; 2.9%), erythromycin-inducing clindamycin resistant (7.4%), and methicillin-resistant Staphylococcus species (21.6%). Pathogens belonging to the Enterobacteriaceae family were observed to undergo directional selection developing resistance against antibiotics ciprofloxacin, piperacillin-tazobactam, cefepime, and cefuroxime. Pathogens in the surgical ward exhibited higher levels of antibiotic resistance, while non-clinical P. aeruginosa and K. pneumoniae strains were more antibiotic-susceptible. Our research assisted in identifying the drugs that can be used to control infections caused by antimicrobial resistant bacteria in the population and in monitoring the prevalence of drug-resistant bacterial pathogens.

Combinatorial efficacy of Manuka honey and antibiotics in the in vitro control of staphylococci and their small colony variants

Introduction

Staphylococci are among the list of problematic bacteria contributing to the global antibiotic resistance (ABR) crisis. Their ability to adopt the small colony variant (SCV) phenotype, induced by prolonged antibiotic chemotherapy, complicates staphylococcal infection control options. Novel and alternative approaches are needed to tackle staphylococcal infections and curb ABR. Manuka honey (MH), a non-antibiotic alternative is recognized for its unique antibacterial activity based on its methylglyoxal (MGO) component.

Methods

In this study, MH (MGO 830+) was tested in combination with gentamicin (GEN), rifampicin (RIF), or vancomycin (VA) against staphylococcal wildtype (WT) and SCVs. To our knowledge, there are no current studies in the literature documenting the effects of MH on staphylococcal SCVs. While Staphylococcus aureus is well-studied for its international ABR burden, limited data exists demonstrating the effects of MH on S. epidermidis and S. lugdunensis whose pathogenic relevance and contribution to ABR is also rising.

Results & discussion

The three staphylococci were most susceptible to RIF (0.06-0.24 μg/ml), then GEN (0.12-0.49 μg/ml), and lastly VA (0.49-0.96 μg/ml). The MICs of MH were 7%, 7-8%, and 6-7% (w/v), respectively. Fractional inhibitory concentration (FIC) evaluations showed that the combined MH + antibiotic effect was either additive (FICI 1-2), or partially synergistic (FICI >0.5-1). While all three antibiotics induced SCVs in vitro, stable SCVs were observed in GEN treatments only. The addition of MH to these GEN-SCV-induction analyses resulted in complete suppression of SCVs (p<0.001) in all three staphylococci, suggesting that MH's antibacterial properties interfered with GEN's SCV induction mechanisms. Moreover, the addition of MH to growth cultures of recovered stable SCVs resulted in the inhibition of SCV growth by at least 99%, indicating MH's ability to prevent subsequent SCV growth. These in vitro analyses demonstrated MH's broad-spectrum capabilities not only in improving WT staphylococci susceptibility to the three antibiotics, but also mitigated the development and subsequent growth of their SCV phenotypes. MH in combination with antibiotics has the potential to not only resensitize staphylococci to antibiotics and consequently require less antibiotic usage, but in instances where prolonged chemotherapy is employed, the development and growth of SCVs would be hampered, providing a better clinical outcome, all of which mitigate ABR.

Incidence of Rifampicin Resistance in Periprosthetic Joint Infection: A Single-Centre Cohort Study on 238 Patients

BACKGROUND

Rifampicin is a pillar in the treatment of periprosthetic joint infection (PJI). However, rifampicin resistance is an increasing threat to PJI treatment. This study explores the incidence of rifampicin-resistant bacteria over time in a Swedish tertiary referral centre and the association of rifampicin resistance with infection-free survival after PJI.

METHODS

The study included 238 staphylococcal PJIs treated between 2001 and 2020 for which susceptibility data for rifampicin were available. Data on causative bacteria, rifampicin resistance, treatment, and outcome were obtained. Kaplan-Meier survival analysis and Cox regression modelling estimated the infection-free cumulative survival and adjusted hazard ratios (HRs) for the risk of treatment failure.

RESULTS

Rifampicin-resistant causative bacteria were identified in 40 cases (17%). The proportion of rifampicin-resistant agents decreased from 24% in 2010-2015 to 12% in 2016-2020. The 2-year infection-free survival rates were 78.6% (95% CI, 66.4-93.1%) for the rifampicin-resistant group and 90.0% (95% CI, 85.8-94.4%) for the rifampicin-sensitive group. Patients with PJI caused by rifampicin-resistant bacteria had an increased risk of treatment failure (adjusted HR, 4.2; 95% CI, 1.7-10.3).

CONCLUSIONS

The incidence of PJI caused by rifampicin-resistant bacteria did not increase over the past 20 years. The risk of treatment failure in PJI caused by rifampicin-resistant bacteria is more than four times that caused by rifampicin-sensitive bacteria, highlighting the importance of limiting the development of rifampicin resistance.

Influences on treatment-seeking and antibiotic use for common illnesses in eastern China

BACKGROUND

Antibiotic resistance rates remain high in China where antibiotics are widely used for common illnesses. This study aimed to investigate the influences on people's decisions on treatment and antibiotic use for common illnesses in eastern China.

METHODS

Semi-structured interviews were conducted with 29 patients recruited through convenience sampling between July 2020 and January 2021 in one hospital in County A in Zhejiang Province, and one hospital and one village clinic in County B in Jiangsu Province, respectively. All interviews were audio-recorded, transcribed verbatim and thematically analysed. This study is nested in a larger interdisciplinary mixed method project and we also compared our qualitative findings with quantitative results from a household survey conducted as part of this wider project.

RESULTS

Participants' decisions about treatment-seeking and antibiotic use for common illnesses were found to be influenced by four interactive domains. (i) Self-evaluation of illness severity: Participants tend to self-treat minor conditions with ordinary medicines first and do not resort to antibiotics unless the condition worsens or is considered inflammation- related. Visiting healthcare facilities is seen as the final option. (ii) Access to and trust in care: These treatment-seeking practices are also associated with the perception, in contrast with retail pharmacies, hospitals provide professional and trustworthy care but are difficult to access, and hence require visiting only for severe illness. (iii) Prior experience: previous medical treatment and experiences of self-medication also influence participants' treatment decisions including the use of antibiotics. (iv) Medication characteristics: Participants view antibiotics as powerful medicines with harms and risks, requiring consumers to carefully trade off benefits and harms before use.

CONCLUSIONS

People's treatment decisions in relation to antibiotic use in eastern China are influenced by an interplay of lay conceptual models of illnesses and antibiotics and broader organisational, social, and contextual factors. Interventions focusing on individual education to incorporate biomedical knowledge into lay understandings, and reducing situational and social incentives for self-medicating with antibiotics by strengthening access to quality professional care, would be helpful in promoting antibiotic stewardship.

Antimicrobial use, healthcare-associated infections, and bacterial resistance in general hospitals in China: the first national pilot point prevalence survey report

The purpose of this study is to implement point prevalence survey (PPS), assess antimicrobial prescribing and resistance in general hospitals and clinical specialties in China, and compare them with similar data from other parts of the world. Twenty general hospitals in China were surveyed in October or November, 2019. A standardized surveillance protocol was used to collect data on patient demographics, diagnosis of infection, the prevalence and intensity of antimicrobial use, prescribing quality, bacterium type and resistance spectrum, and the prevalence and type of healthcare-associated infections (HAIs). Overall, 10,881 beds and 10,209 inpatients were investigated. The overall prevalence of antibiotic use was 37.00%, the use of antibiotic prophylaxis in surgical patients was high (74.97%). The intensity of antimicrobial use was 61.25 DDDs/100 patient days. Only 11.62% of antimicrobial prescriptions recorded the reason for prescribing. Intravenous or combination treatments comprised 92.02% and 38.07%, respectively, and only 30.65% of prescriptions referred to a microbiological or biomarker tests. The incidence of HAIs in all patients was 3.79%. The main associated factors for HAIs included more frequent invasive procedures (27.34%), longer hospital stay (> 1-week stay accounting for 51.47%), and low use of alcohol hand rubs (only 29.79% placed it bedside). Most of the resistant bacteria declined; only carbapenem-resistant Enterobacter is higher than previously reported. The prevalence of antibiotic use in general hospitals fell significantly, the overall bacterial resistance declined, and the incidence of HAI was low. However, the low quality of antimicrobial use requires urgent attention.

Clinical and microbiological characteristics of rifampicin-resistant MRSA bacteraemia

OBJECTIVES

The clinical significance of rifampicin resistance in Staphylococcus aureus infections has not been demonstrated. Here, we evaluated the clinical characteristics of rifampicin-resistant S. aureus infection.

METHODS

Data were collected from adult patients who were hospitalized with MRSA bacteraemia between March 2007 and May 2020 at a tertiary hospital in South Korea. The clinical characteristics and treatment outcomes of patients infected with rifampicin-resistant MRSA were compared with those of rifampicin-susceptible isolates. All-cause death and recurrence of MRSA infection were assessed for 90 days.

RESULTS

Of the 961 patients with MRSA bacteraemia, 61 (6.3%) were infected by rifampicin-resistant isolates. The type of infection focus and duration of bacteraemia did not significantly differ between the two groups. Rifampicin-resistant MRSA isolates were more likely to have multidrug resistance and a higher vancomycin MIC relative to the rifampicin-susceptible isolates. The 90-day recurrence rate was higher in the patients infected with rifampicin-resistant MRSA compared with those with rifampicin-susceptible MRSA (18.0% versus 6.2%, P < 0.001), whereas the 90-day mortality was comparable between the two groups (27.9% versus 29.2%, P = 0.94). After adjusting for potential confounding factors, rifampicin resistance was significantly associated with 90-day recurrence (subdistributional HR: 2.31; 95% CI: 1.05-5.10; P = 0.04).

CONCLUSIONS

Rifampicin-resistant MRSA isolates showed distinct microbiological features in terms of multidrug resistance and a high vancomycin MIC. Although the management of MRSA bacteraemia was not significantly different between the two groups, recurrence was significantly more common in the rifampicin-resistant group. Rifampicin resistance may play a significant role in infection recurrence.

Non-typeable Haemophilus influenzae airways infection: the next treatable trait in asthma?

Asthma is a complex, heterogeneous condition that affects over 350 million people globally. It is characterised by bronchial hyperreactivity and airways inflammation. A subset display marked airway neutrophilia, associated with worse lung function, higher morbidity and poor response to treatment. In these individuals, recent metagenomic studies have identified persistent bacterial infection, particularly with non-encapsulated strains of the Gram-negative bacterium Haemophilus influenzae. Here we review knowledge of non-typeable H. influenzae (NTHi) in the microbiology of asthma, the immune consequences of mucosal NTHi infection, various immune evasion mechanisms, and the clinical implications of NTHi infection for phenotyping and targeted therapies in neutrophilic asthma. Airway neutrophilia is associated with production of neutrophil chemokines and proinflammatory cytokines in the airways, including interleukin (IL)-1β, IL-6, IL-8, IL-12, IL-17A and tumour necrosis factor. NTHi adheres to and invades the lower respiratory tract epithelium, inducing the NLR family pyrin domain containing 3 (NLRP3) and absent in melanoma 2 (AIM2) inflammasomes. NTHi reduces expression of tight-junction proteins, impairing epithelial integrity, and can persist intracellularly. NTHi interacts with rhinoviruses synergistically via upregulation of intracellular cell adhesion molecule 1 and promotion of a neutrophilic environment, to which NTHi is adapted. We highlight the clinical relevance of this emerging pathogen and its relevance for the efficacy of long-term macrolide therapy in airways diseases, we identify important unanswered questions and we propose future directions for research.

Appropriateness of Antibiotic Prescriptions in Chinese Primary Health Care and the Impact of the COVID-19 Pandemic: A Typically Descriptive and Longitudinal Database Study in Yinchuan City

Background: The appropriateness of antibiotic prescriptions in primary care has not been well evaluated in China in recent years. Furthermore, the impact of coronavirus disease 2019 (COVID-19) on antibiotic prescriptions has not yet been investigated in China. We aimed to assess the appropriateness of antibiotic prescriptions and to evaluate the potential association between the COVID-19 pandemic and antibiotic prescriptions in primary care settings of Yinchuan, a city in China. Methods: This study included 155 primary care institutions and 10,192,713 outpatient visits. Outpatient prescriptions were classified as appropriate, potentially appropriate, inappropriate, or not linked to any diagnosis for antibiotic use following a validated evaluation scheme. Interrupted time-series analyses were performed to assess the effects of the COVID-19 pandemic on antibiotic prescriptions in Chinese primary care facilities. Results: During the study period, 1,287,678 (12.6%, 95% confidence interval [12.6-12.7]) of 10,192,713 outpatient visits in primary care resulted in antibiotic prescriptions. Among 1,287,678 antibiotic prescriptions, 653,335 (50.7% [50.6-50.9]) were inappropriate, 463,081 (36.0% [35.8-36.1]) were potentially appropriate, 171,056 (13.3% [13.1-13.5]) were appropriate, and 206 could not be linked to any diagnosis. Furthermore, patient, physician, and institutional factors were associated with inappropriate antibiotic prescriptions; there was an overall decreasing trend in the proportions of inappropriate antibiotic prescriptions, with the highest level in 2017 (67.1% [66.8-67.5]) and the lowest in 2021 (40.8% [40.3-41.3]). A total of 1,416,120 individual antibiotics were prescribed, of which 1,087,630 (76.8%) were broad-spectrum and 777,672 (54.9%) were classified in the World Health Organization's "Watch" category. In addition, the COVID-19 pandemic was associated with changes of -2.8% (-4.4 to -1.3) in the level and 0.3% (0.2-0.3) in the monthly trend of antibiotic prescription rates, as well as changes of -5.9% (-10.2 to -1.5) in the level and 1.3% (1.0-1.6) in the monthly trend of the proportions of inappropriate antibiotic prescriptions. Conclusion: More than half of the antibiotic prescriptions were inappropriate during the study period in primary care in Yinchuan. The COVID-19 pandemic may be associated with a decrease in the overall and inappropriate use of antibiotics in primary care settings in China.

Antibiotic Stewardship in Retail Pharmacies and the Access-Excess Challenge in China: A Policy Review

In China, efforts to restrict excessive antibiotic consumption may prevent sufficient access to these life-saving drugs among the most deprived in society because of the weak primary health care system. This makes antibiotic stewardship in the retail pharmacy sector a particular challenge. We conducted an analysis to examinate policies on antibiotic sales in retail pharmacies in China and how tensions between ‘excess’ and ‘access’ are managed. The analysis was guided by the Walt and Gilson health policy analysis triangle to systematically analyse policies based on the content of policies, contexts, governance processes, and actors. Nine research studies and 25 documents identified from national and international sources were extracted, grouped into categories, and examined within and across records and categories. As of 2020, eight key policies have been introduced in China that focus on two areas: dispending prescribed medicines or antimicrobials with a prescription and having a licensed pharmacist present in the retail pharmacies, with approaches having changed over time. Inappropriate sales of antibiotics are still common in retail pharmacies, which can be linked to the lack of consistency and enforcement of published policies, the profit-driven nature of retail pharmacies, and the displacement of the demand for antibiotics from clinical into less regulated settings.

Positive association between the use of macrolides in food-producing animals and pneumococcal macrolide resistance: a global ecological analysis

BACKGROUND

The reasons underpinning the large differences in the prevalence of resistance to macrolides in Streptococcus pneumoniae are imperfectly understood. We assessed if the volume of macrolides used in food-animals could play a role.

METHODS

Logistic regression was used to assess if the country-level prevalence of pneumococcal macrolide resistance was associated with country-level macrolide consumption in food animals and humans.

RESULTS

In both univariate and multivariate models, macrolide use in food-producing animals was significantly associated with pneumococcal macrolide resistance (coeff. = 339, 95% CI 21 - 658; P = 0.037).

CONCLUSIONS

In vitro and individual-level studies are required to verify or refute the hypothesis that macrolides used in food animals can promote the spread of macrolide resistance in humans.

Antibiotic Stewardship und chronische Lungenerkrankungen

Hintergrund

Ziel dieser Arbeit

Material und Methoden

Ergebnisse und Diskussion

Molecular Characterization of Rifampicin-Resistant Staphylococcus aureus Isolates from Retail Foods in China

This study investigated the molecular characteristics of rifampin-resistant (RIF-R) Staphylococcus aureus isolates recovered from 4300 retail food samples covering most provincial capitals in China, from 2011 to 2016. Of the 1463 S. aureus enrolled, 149 isolates (142 MSSA and 7 MRSA) were identified as rifampicin-resistant, including 20 high-level (MICs ≥ 8 μg/mL) and 129 low-level (MICs between 2 and 4 μg/mL) rifampicin-resistant strains. Most of the RIF-R S. aureus isolates were resistant to more than three antibiotics. The mutations in the rifampicin resistance-determining region of the rpoB gene were studied in all RIF-R strains. All of the strains presented the mutational change 481 His/Asn and five isolates presented an additional mutation, including 477 Asp/Tyr, 527 Ile/Met, and 466 Leu/Ser, respectively. Thirteen STs and twenty-one spa types were represented, in which five MRSA showed non-type SCCmec and the remaining MRSA belonged to SCCmec type IV-where, ST1-t127 was the predominant type from all of the isolates, while ST398-t034 was the predominant type for the MRSA isolates. In this study, we found that the food-related RIF-R S. aureus may have a unique genetic background selection. However, the scenario regarding the presence of RIF-R S. aureus, especially MRSA, in retail food in China is not favorable and warrants public attention.

The promise of endogenous and exogenous riboflavin in anti-infection

To resolve the growing problem of drug resistance in the treatment of bacterial and fungal pathogens, specific cellular targets and pathways can be used as targets for new antimicrobial agents. Endogenous riboflavin biosynthesis is a conserved pathway that exists in most bacteria and fungi. In this review, the roles of endogenous and exogenous riboflavin in infectious disease as well as several antibacterial agents, which act as analogues of the riboflavin biosynthesis pathway, are summarized. In addition, the effects of exogenous riboflavin on immune cells, cytokines, and heat shock proteins are described. Moreover, the immune response of endogenous riboflavin metabolites in infectious diseases, recognized by MHC-related protein-1, and then presented to mucosal associated invariant T cells, is highlighted. This information will provide a strategy to identify novel drug targets as well as highlight the possible clinical use of riboflavin.

Antibiotic resistance in neonates in China 2012-2019: A multicenter study

BACKGROUND

To investigate antibiotic resistance of pathogens responsible for neonatal invasive bacterial infections (IBIs) in China.

METHODS

Cross-sectional study of neonates with IBI evaluated in nine hospitals in China (January 2012-August 2019). Antibiotic resistance patterns of pathogens responsible for neonatal IBIs were analyzed.

RESULTS

Of 3770 full-term neonates who were subjected to lumbar puncture and a blood culture, IBIs were diagnosed in 460 neonates (12.2%). Escherichia coli and Group B Streptococcus (GBS) were the leading pathogens, followed by Enterococcus spp, and Staphylococcus aureus. E. coli expressed high resistance to ampicillin (72.0%) and third-generation cephalosporins (cefotaxime, 34.8%; ceftriaxone, 38.1%). The prevalence of extended spectrum beta-lactamase (ESBL)-producing E. coli was 34.1%. The proportions of E. spp resistant to penicillin and ampicillin were 60% and 54.1%. All S. aureus showed resistance to ampicillin and penicillin. The resistance rate of S. aureus to methicillin was 50%. Although all GBS were susceptible to penicillin and ampicillin, the proportions of GBS resistant to erythromycin and clindamycin were 75.9% and 77.3%. Antibiotic susceptibility appeared to improve in 2019. Susceptibility of E. coli to ampicillin, cefotaxime, and ceftriaxone improved to 42.9%, 76.9%, and 71.4% in 2019, compared with 12.5%, 37.5%, and 50% in 2012. The prevalence of ESBL-producing E. coli declined to 20% in 2019, lower than 100% in 2012. Susceptibility of GBS to erythromycin and clindamycin improved from 0% in 2012 to 28.6% and 25% in 2019.

CONCLUSIONS

The prevalence of antibiotic resistance is high in neonates in China, although there is a favorable declining trend in recent years.

Using Weibo and WeChat social media channels to assess public awareness and practices related to antimicrobial resistance, China, 2019

Background

Antimicrobial resistance (AMR) is a global healthcare problem, including in China where high rates of resistance to common bacterial infections have been documented. In 2016, the National Health and Family Planning Commission (NHFPC) in China established a comprehensive strategic plan to increase awareness about AMR through education programs.

Methods

We conducted an online survey to assess changes in public knowledge, awareness and practices related to AMR in China since 2016. The survey was administered using China’s national and provincial level 12320 Health Hotline Weibo (micro-blog site) and WeChat (text messaging service) social media accounts from April 12, 2019 to May 7, 2019. All persons ≥16 years of age able to read Chinese were eligible to participate.

Results

A total of 2773 respondents completed the survey. Of the 2633 respondents indicating recent use of antibiotics, 84% (2223) reported obtaining their course of antibiotics from a hospital or pharmacy, 9% (246) of respondents reported using antibiotics saved from a previous prescription or treatment course, and 42% (1115) of respondents reported that they had stopped taking antibiotics as soon as they started feeling better. Most respondents correctly indicated that antibiotics can effectively treat urinary tract infections (86% [2388]) and skin infections (76% [2119]), but many incorrectly indicated that antibiotics can also treat viral infections such as measles (32% [889]) or a cold or flu (26% [726]). Of all respondents, 95% (2634) had heard of ‘antibiotic resistance’. Almost half (47% [1315]) reported using antibiotics within the last 6 months.

Conclusion

While awareness of AMR was high in this survey of social media users in China, inappropriate antibiotic use remains common, including the believe that antibiotics can effectively treat viral infections. Multiple interventions targeting the correct use of antibiotics and information on the cause AMR are likely needed. The 12320 Health Hotline provides a platform for conducting routine surveys to monitor antibiotic use and knowledge about AMR.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10648-5.

Design of a novel antimicrobial peptide 1018M targeted ppGpp to inhibit MRSA biofilm formation

Methicillin-resistant staphylococcus aureus (MRSA) and its biofilm infection were considered as one of the main international health issues. There are still many challenges for treatment using traditional antibiotics. In this study, a mutant peptide of innate defense regulator (IDR-)1018 named 1018M was designed based on molecular docking and amino acid substitution technology. The antibacterial/biofilm activity and mechanisms against MRSA of 1018M were investigated for the first time. The minimum inhibitory concentration (MIC) of 1018M was reduced 1 time (MIC = 2 μg/mL) compared to IDR-1018. After treatment with 32 μg/mL 1018M for 24 h, the percentage of biofilm decreased by 78.9%, which was more effective than the parental peptide. The results of mechanisms exploration showed that 1018M was more potent than IDR-1018 at destructing bacterial cell wall, permeating cell membrane (20.4%–50.1% vs 1.45%–10.6%) and binding to stringent response signaling molecule ppGpp (increased 27.9%). Additionally, the peptides could also exert their activity by disrupting genomic DNA, regulating the expression of ppGpp metabolism and biofilm forming related genes (RSH, relP, relQ, rsbU, sigB, spA, codY, agrA and icaD). Moreover, the higher temperature, pH and pepsase stabilities provide 1018M better processing, storage and internal environmental tolerance. These data indicated that 1018M may be a potential candidate peptide for the treatment of MRSA and its biofilm infections.

Molecular characterization and antibiotic resistance of Acinetobacter baumannii in cerebrospinal fluid and blood

The increasing prevalence of carbapenem-resistant Acinetobacter baumannii (CRAB) caused nosocomial infections generate significant comorbidity and can cause death among patients. Current treatment options are limited. These infections pose great difficulties for infection control and clinical treatment. To identify the antimicrobial resistance, carbapenemases and genetic relatedness of Acinetobacter baumannii isolates from cerebrospinal fluid (CSF) and blood, a total of 50 nonrepetitive CSF isolates and 44 blood isolates were collected. The resistance phenotypes were determined, and polymerase chain reaction (PCR) was performed to examine the mechanisms of carbapenem resistance. Finally, multilocus sequence typing (MLST) was conducted to determine the genetic relatedness of these isolates. It was observed that 88 of the 94 collected isolates were resistant to imipenem or meropenem. Among them, the bla_OXA-23 gene was the most prevalent carbapenemase gene, with an observed detection rate of 91.5% (86/94), followed by the bla_OXA-24 gene with a 2.1% detection rate (2/94). Among all carbapenem-resistant Acinetobacter baumannii (CRAB) observations, isolates with the bla_OXA-23 gene were resistant to both imipenem and meropenem. Interestingly, isolates positive for the bla_OXA-24 gene but negative for the bla_OXA-23 gene showed an imipenem-sensitive but meropenem-resistant phenotype. The MLST analysis identified 21 different sequence types (STs), with ST195, ST540 and ST208 most frequently detected (25.5%, 12.8% and 11.7%, respectively). 80 of the 94 isolates (85.1%) were clustered into CC92 which showed a carbapenem resistance phenotype (except AB13). Five novel STs were detected, and most of them belong to CRAB. In conclusion, these findings provide additional observations and epidemiological data of CSF and blood A. baumannii strains, which may improve future infection-control measures and aid in potential clinical treatments in hospitals and other clinical settings.

The Effectiveness of an Educational Intervention on Knowledge, Attitudes and Reported Practices on Antibiotic Use in Humans and Pigs: A Quasi-Experimental Study in Twelve Villages in Shandong Province, China

Our aim was to evaluate the effectiveness of an intervention for residents in rural China on knowledge, attitudes and reported practices (KAP) on antibiotic use in humans and pigs. A quasi-experimental study was conducted in 12 villages in rural Shandong province, divided into intervention and control groups, covering a two-year period from July 2015 to June 2017. A package of health education-based interventions including training sessions, speakerphone messages, posters and handbooks for residents was developed and implemented over a one-year period to improve the use of antibiotics in humans and pigs. The intervention net effects were evaluated by Difference-in-Difference (DID) analysis based on responses to a questionnaire concerning KAP towards antibiotic use in humans and pigs. A total of 629 participants completed both baseline and post-trial questionnaires, including 127 participants with backyard pig farms. Significant improvements were found in KAP towards antibiotic use in humans, but changes related to antibiotic use for pigs were not significant. Participants who were in the intervention group (p < 0.001) were more likely to have improved their knowledge on antibiotic use in humans. Participants who had higher attitude scores were less likely to report self-medicating with stored antibiotics in the previous year (p < 0.001). Our results suggest that our health education-based intervention was effective in improving KAP on human antibiotic use, but it had little effect regarding antibiotic use for pigs.

Change in Antibiotic Use in Secondary and Tertiary Hospitals Nationwide After a National Antimicrobial Stewardship Campaign Was Launched in China, 2011-2016: An Observational Study

BACKGROUND

An antimicrobial stewardship campaign was launched in 2011 by the Ministry of Health. This study aimed to assess the achievements and trends in the clinical use of antibiotics in secondary and tertiary hospitals following this campaign in China.

METHODS

This observational study analyzed nationwide hospital antibiotic procurement and consumption data and antibiotic-resistance surveillance data based on claims filed in 2010-2016.

RESULTS

After a 6-year national campaign, the proportion of outpatients and surgical patients who received antibiotic treatment decreased from 19.5% to 8.5% and from 97.9% to 38.3%, respectively. The intensity of antibiotic use among inpatients decreased from 85.3±29.8 defined daily dosage (DDD) per 100 patient days to 48.5±8.0 DDD per 100 patient days. Moreover, the antibiotic procurement expenditure among hospitals declined from 22.3% of total drug procurement costs in 2010 to 12.1% in 2016, although total drug procurement costs doubled during that time. The incidence of methicillin-resistant Staphylococcus aureus isolates also dropped (from 54.4% in 2010 to 34.4% in 2016), as did the proportion of carbapenem-resistant Pseudomonas aeruginosa isolates (from 30.8% to 22.3%).

CONCLUSIONS

The 6-year campaign successfully reduced antibiotic consumption and irrational drug use in Chinese hospitals which was associated with declines in the prevalence of common antibiotic-resistant bacteria.

Treatment options in type-2 low asthma

Monoclonal antibodies targeting IgE or the type-2 cytokines interleukin (IL)-4, IL-5 and IL-13 are proving highly effective in reducing exacerbations and symptoms in people with severe allergic and eosinophilic asthma, respectively. However, these therapies are not appropriate for 30-50% of patients in severe asthma clinics who present with non-allergic, non-eosinophilic, "type-2 low" asthma. These patients constitute an important and common clinical asthma phenotype, driven by distinct, yet poorly understood pathobiological mechanisms. In this review we describe the heterogeneity and clinical characteristics of type-2 low asthma and summarise current knowledge on the underlying pathobiological mechanisms, which includes neutrophilic airway inflammation often associated with smoking, obesity and occupational exposures and may be driven by persistent bacterial infections and by activation of a recently described IL-6 pathway. We review the evidence base underlying existing treatment options for specific treatable traits that can be identified and addressed. We focus particularly on severe asthma as opposed to difficult-to-treat asthma, on emerging data on the identification of airway bacterial infection, on the increasing evidence base for the use of long-term low-dose macrolides, a critical appraisal of bronchial thermoplasty, and evidence for the use of biologics in type-2 low disease. Finally, we review ongoing research into other pathways including tumour necrosis factor, IL-17, resolvins, apolipoproteins, type I interferons, IL-6 and mast cells. We suggest that type-2 low disease frequently presents opportunities for identification and treatment of tractable clinical problems; it is currently a rapidly evolving field with potential for the development of novel targeted therapeutics.

Patients without records and records without patients: review of patient records in primary care and implications for surveillance of antibiotic prescribing in rural China

BACKGROUND

We need to monitor patterns of antibiotic prescribing in order to develop and evaluate antibiotic stewardship interventions in rural China. As part of a multidisciplinary study of antibiotic use in Anhui Province we assessed the validity of electronic records (e-records) as a source of surveillance data.

METHODS

One township healthcare centre and one village clinic were selected in each of three different counties. Patients with symptoms of Upper Respiratory Tract Infection (URTI), exacerbation of Chronic Obstructive Pulmonary Disease (COPD) or Urinary Tract Infection (UTI) were recruited consecutively. Researchers observed and documented clinic consultations and interviewed each of the study participants. E-records were compared to clinic observations and patient interviews.

RESULTS

A total of 1030 patients were observed in clinic. Antibiotics were prescribed in 917 (89%) of consultations. E-records were created only for individuals with health insurance, with considerable between-site variation in completeness (0 to 98.7% of clinic consultations) and in the timing of documentation (within-consultation up to weeks afterwards). E-record accuracy was better in relation to antibiotics (82.8% of e-records accurately recorded what was prescribed in clinic) than for diagnosis and symptoms (45.0 and 1.1% accuracy). Only 31 participants (3.0%) presented with UTI symptoms.

CONCLUSIONS

We have confirmed very high rates of outpatient antibiotic prescribing in rural Anhui province. E-records could provide useful information to inform stewardship interventions, however they may be inaccurate and/or biased. Public Health authorities should focus on improving technical infrastructure and record-keeping culture in outpatient settings. Further research is needed into community treatment of UTIs.

A comparative genomic analysis between methicillin-resistant Staphylococcus aureus strains of hospital acquired and community infections in Yunnan province of China

BACKGROUND

Currently, Staphylococcus aureus is one of the most important pathogens worldwide, especially for methicillin-resistant S. aureus (MRSA) infection. However, few reports referred to patients' MRSA infections in Yunnan province, southwest China.

METHODS

In this study, we selected representative MRSA strains from patients' systemic surveillance in Yunnan province of China, performed the genomic sequencing and compared their features, together with some food derived strains.

RESULTS

Among sixty selective isolates, forty strains were isolated from patients, and twenty isolated from food. Among the patients' strains, sixteen were recognized as community-acquired (CA), compared with 24 for hospital-acquired (HA). ST6-t701, ST59-t437 and ST239-t030 were the three major genotype profiles. ST6-t701 was predominated in food strains, while ST59-t437 and ST239-t030 were the primary clones in patients. The clinical features between CA and HA-MRSA of patients were statistical different. Compared the antibiotic resistant results between patients and food indicated that higher antibiotic resistant rates were found in patients' strains. Totally, the average genome sizes of 60 isolates were 2.79 ± 0.05 Mbp, with GC content 33% and 84.50 ± 0.20% of coding rate. The core genomes of these isolates were 1593 genes. Phylogenetic analysis based on pan-genome and SNP of strains showed that five clustering groups were generated. Clustering ST239-t030 contained all the HA-MRSA cases in this study; clustering ST6-t701 referred to food and CA-MRSA infections in community; clustering ST59-t437 showed the heterogeneity for provoking different clinical diseases in both community and hospital. Phylogenetic tree, incorporating 24 isolates from different regions, indicated ST239-t030 strains in this study were more closely related to T0131 isolate from Tianjin, China, belonged to 'Turkish clade' from Eastern Europe; two groups of ST59-t437 clones of MRSA in Yunnan province were generated, belonged to the 'Asian-Pacific' clone (AP) and 'Taiwan' clone (TW) respectively.

CONCLUSIONS

ST239-t030, ST59-t437 and ST6-t701 were the three major MRSA clones in Yunnan province of China. ST239-t030 clonal Yunnan isolates demonstrated the local endemic of clone establishment for a number of years, whereas ST59-t437 strains revealed the multi-origins of this clone. In general, genomic study on epidemic clones of MRSA in southwest China provided the features and evolution of this pathogen.

Knowledge, attitudes and practices relating to antibiotic use and antibiotic resistance among backyard pig farmers in rural Shandong province, China

China is among the world's largest consumers of antibiotics for livestock, and the demand for meat protein continues to rise. Pig production takes place at a range of facilities, including backyard pig farms. The aim of this study was to describe the knowledge, attitudes and practices of backyard pig farmers concerning antibiotic use and resistance, and to observe household storage of antibiotics for use in pigs. We conducted a cross-sectional questionnaire survey among 271 rural residents with backyard pig farms in 12 villages in one town in Shandong province. The median number of pigs per backyard farm was 14, and 82 % (222/271) of participants reported not having had any training about raising pigs. Eighteen percent of participants (48/271) reported always or often adding antibiotics to feed to keep pigs healthy and prevent diseases, and a third (88/271) of participants believed that pigs should be given antibiotics when they stop eating. Thirty percent (82/271) reported having bought antibiotics in the previous year without having first spoken with a veterinarian. Antibiotics accounted for over half of all medicines stored (55 %, 197/358), and were observed in 31 % of all households (83/271). Less than half of participants (45 %, 37/83) from households in which antibiotics for pig use were found knew that they were storing antibiotics. The most common class of antibiotics stored for use in pigs was (Q)J01C beta-lactam antibiotics, penicillins (19 %, 37/197), followed by (Q)J01F macrolides, lincosamides and streptogramins (14 %, 28/197), and (Q)J01M quinolones (12 %, 25/197). These results provide important insights into how backyard pig farmers are using antibiotics in rural China and suggest potential targets for interventions to reduce unnecessary and inappropriate use.

Widespread illegal sales of antibiotics in Chinese pharmacies - a nationwide cross-sectional study

Background

Access to antibiotics without a prescription from retail pharmacies has been described as a major contributor to anti-microbial resistance (AMR) globally. In the context of high rates of AMR, the Chinese government has recently introduced strict policies regarding hospital antibiotic use, but the existing ban on antibiotic sales without prescription in retail pharmacies has not been strongly enforced. In 2016, a goal of prescription-only antibiotics by 2020 was announced. The objective of the study was to determine progress towards the 2020 goal, through estimating the proportion of retail pharmacies selling antibiotics without prescription across the three regions of mainland China.

Methods

Using the Simulated Patient method, we conducted a cross-sectional survey across purposively-sampled retail pharmacies in urban and rural areas of 13 provinces in eastern, central and western China. Medical students presented a scenario of a mild upper respiratory tract infection, following a strict three-step protocol. They recorded the pharmacy characteristics, and details of their experience, including at which step antibiotics were offered.

Results

Complete data were obtained from 1106 pharmacies. Antibiotics were obtained in 925 (83.6, 95% CI: 81.5, 85.8%) pharmacies without a prescription, 279 (25.2%) at Stage 1 (symptoms only described), 576 (52.1%) at stage 2 (asked for antibiotics), and 70 (6.3%) at Stage 3 (asked for penicillin or cephalosporins). There were significant differences between provinces, with antibiotic access (at any stage) ranging from 57.0% (57/100) in Zhejiang (81/82) to 98.8% in Guizhou. However, there were no significant differences in access to antibiotics by level of city, county, township or village (P = 0.25), whether the pharmacy was part of a chain or independent (P = 0.23), whether a licensed pharmacist was attending (P = 0.82) or whether there was a sign saying that prescriptions were required for antibiotics (P = 0.19).

Conclusions

It is easy to obtain antibiotics without a prescription in retail pharmacies in China, despite the fact it is against the law. This must be addressed as part of the wider anti-microbial stewardship effort which could include intense enforcement of the existing law, supported by a public education campaign.

Diagnostic ability and inappropriate antibiotic prescriptions: a quasi-experimental study of primary care providers in rural China

Background

China has one of the highest rates of antibiotic resistance. Existing studies document high rates of antibiotic prescription by primary care providers but there is little direct evidence on clinically inappropriate use of antibiotics or the drivers of antibiotic prescription.

Methods

To assess clinically inappropriate antibiotic prescriptions among rural primary care providers, we employed unannounced standardized patients (SPs) who presented three fixed disease cases, none of which indicated antibiotics. We compared antibiotic prescriptions of the same providers in interactions with SPs and matching vignettes assessing knowledge of diagnosis and treatment to assess overprescription attributable to deficits in diagnostic knowledge, therapeutic knowledge and factors that lead providers to deviate from their knowledge of best practice.

Results

Overall, antibiotics were inappropriately prescribed in 221/526 (42%) SP cases. Compared with SP interactions, prescription rates were 29% lower in matching clinical vignettes (42% versus 30%, P < 0.0001). Compared with vignettes assessing diagnostic and therapeutic knowledge jointly, rates were 67% lower in vignettes with the diagnosis revealed (30% versus 10%, P < 0.0001). Antibiotic prescription in vignettes was inversely related to measures of diagnostic process quality (completion of checklists).

Conclusions

Clinically inappropriate antibiotic prescription is common among primary care providers in rural China. While a large proportion of overprescription may be due to factors such as financial incentives tied to drug sales and perceived patient demand, our findings suggest that deficits in diagnostic knowledge are a major driver of unnecessary antibiotic prescriptions. Interventions to improve diagnostic capacity among providers in rural China are needed.

Antibiotic use in people and pigs: a One Health survey of rural residents' knowledge, attitudes and practices in Shandong province, China

Objectives

To evaluate rural residents' knowledge, attitudes and practices (KAP) towards antibiotic use in humans and pigs, among individuals with and without backyard pig farms living in Shandong province, China.

Methods

We conducted a cross-sectional questionnaire study among residents in 12 villages, and directly observed medicines stored in households for humans and pigs.

Results

In total, 769 residents participated, including 330 backyard pig farmers. Respondents had low levels of knowledge about antibiotics. A quarter of participants had bought one or more antibiotics from a pharmacy without a prescription in the previous year, and this was more common among pig farmers who had bought antibiotics for their pigs without consulting a vet (49% versus 25%, P < 0.001). Stored antibiotics for human use were found in 42% of households, and 70% of participants from these households did not know they were storing antibiotics. Thirty-one percent of backyard pig farmers were storing antibiotics for pig use. Farmers who thought it was good to store leftover antibiotics for their pigs were more likely to have stored antibiotics for pigs (41% versus 20%) and for humans (47% versus 32%; both P < 0.01). A fifth of participants thought their own actions were important for controlling antibiotic resistance.

Conclusions

We found differences in the KAP of backyard pig farmers and non-pig farmers to antibiotics, and parallels between pig farmers' attitudes and behaviours towards antibiotic use in pigs and in humans. Our findings reinforce the need for context-adapted multifaceted interventions to improve antibiotic use and provide suggestions for targeting educational approaches.

Evolution of resistance mechanisms and biological characteristics of rifampicin-resistant Staphylococcus aureus strains selected in vitro

Background

We aimed to determine the evolutionary pathways of rifampicin resistance in Staphylococcus aureus, and the impact of resistance mutations in the rpoB gene on fitness.

Methods

Three clinical strains and one reference strain were used to select for rifampicin-resistant S. aureus variants. The mutations responsible for rifampicin resistance in all of the selected isolates in vitro were investigated by polymerase chain reaction (PCR) and DNA sequencing. To compare the fitness cost of rpoB mutations against their corresponding original isolates, we performed bacterial growth curve assays, static biofilm assays, in vitro competition experiments and an infection model of Galleria mellonella larvae.

Results

We obtained four rifampicin-resistant S. aureus isolates that showed high levels of resistance to rifampicin with a minimal inhibitory concentration (MIC) of 128 mg/L, and all isolates had a mutation at position 481 (H481F/Y) in RpoB. A broth microdilution assay indicated that mutation of H481F/Y did not affect susceptibility to common antibacterial drugs but slightly increased the vancomycin MIC. To identify the pathways involved in the development of rifampicin resistance, 32 variants (eight mutants for each strain) and four original isolates were selected for gene sequencing. Different generations of isolates were found to harbor various mutations sites. Compared with the corresponding original isolates, an in vitro fitness assay of the variant isolates showed that growth and virulence were reduced, with a statistically significantly decreased fitness, whereas the capacity for biofilm formation was elevated.

Conclusions

Our findings suggested that the acquisition of rifampicin resistance in S. aureus was dynamic and was associated with a significant fitness cost.

Electronic supplementary material

The online version of this article (10.1186/s12866-019-1573-9) contains supplementary material, which is available to authorized users.

Phenotypic and genotypic detection of metallo-β-lactamases in A. baumanii isolates obtained from clinical samples in Shahrekord, southwest Iran

OBJECTIVE

Acinetobacter baumanii is a pathogenic bacterium that is the cause of many nosocomial infections. This study aimed to determine metallo-β-lactamases (MBL) produced by the A. baumanii isolates obtained from clinical samples in Shahrekord, southwest Iran.

RESULTS

A total of 100 A. baumanii were isolated from 250 clinical samples between June 2013 and June 2014. Then, the isolates were identified by biochemical tests, and MBL screening was conducted by the phenotypic tests modified Hodge, EDTA-disk synergy (EDS), combined disk (CD) and AmpC disc after antibiotic sensitivity test. Using PCR technique the bla genes were detected. Eighty-five (85%) isolates were resistant to meropenem and imipenem. Phenotypic tests showed that out of the 100 isolates, 46, 59, 50, 65 and 65 isolates were positive: AmpC disk, CD, EDS, Modified Hodge and E-test MBL respectively. Gene detection by PCR showed that 23 isolates carried the VIM-1 gene and only three isolates carried the IMP-1 gene. The prevalence of metallo-β-lactamases isolates containing A. baumanii is increasing. Furthermore, the coexistence of various carbapenemases is dominantly act as a major problem. Continuous monitoring of the infections related to these bacteria should be considered to plan an alternative and new therapeutic strategies.

Trends and correlation of antibiotic susceptibility and antibiotic consumption at a large teaching hospital in China (2007-2016): a surveillance study

PURPOSE

To evaluate the trends and correlation between the antibiotic consumption and susceptibility of eight most frequent isolates in the First Affiliated Hospital of Zhejiang University (2007-2016).

METHOD

This study was based on the yearly surveillance data in a 2500-bed capacity tertiary-care teaching hospital. Trends and correlation were, respectively, analyzed by linear regression and Pearson's correlation coefficient.

RESULTS

The consumption of all antibiotics decreased by 10.8% over time, especially first-generation cephalosporins (p=0.001), fourth-generation cephalosporins (p=0.01), aminoglycosides (p<0.001), and fluoroquinolones (p<0.001), but increased remarkably in linezolid, carbapenems, glycopeptides, and third-generation cephalosporins (3GCs). 72.7% of trend analyses indicated increased susceptibility to antibiotics with remarkably decreased consumption. In particular, susceptibility to aminoglycosides and fluoroquinolones remarkably increased in seven of eight pathogens and negatively correlated with the corresponding antibiotic consumption (p<0.05). Isolation density significantly declined in methicillin-resistant Staphylococcus aureus (54.9-41.3%, p=0.009) and in extended-spectrum β-lactamase producing Klebsiella pneumoniae (42.4-15.6%, p=0.007), which positively correlated with the consumption of fluoroquinolones. The susceptibility to antibiotics with increased consumption was almost stable. Decreased trends were only found in K. pneumoniae to imipenem (81-71.3%, p=0.046) and cefoperazone/sulbactam (70.8-61.0%, p=0.014) and in Acinetobacter baumannii to cefoperazone/sulbactam (59-28%, p=0.007), which negatively correlated with the consumption of carbapenems (r=-0.649, p=0.042) and 3GCs/β-lactamase inhibitors (p<0.05), respectively. The consumption of glycopeptides even positively correlated with the growing susceptibility to vancomycin in Enterococcus faecium (r=0.633, p=0.049) and Enterococcus faecalis (r=0.752, p=0.012).

CONCLUSION

The susceptibility to antibiotics with decreased consumption increased remarkably, but maintained stable to those with growing consumption. The stricter management of carbapenems and 3GCs is necessary.

Impact of antimicrobial stewardship managed by clinical pharmacists on antibiotic use and drug resistance in a Chinese hospital, 2010-2016: a retrospective observational study

OBJECTIVES

'National Special Stewardship in the Clinical Use of Antibiotics' was put forward in July 2011 in China. We aimed to retrospectively evaluate the impact of antimicrobial stewardship (AMS) managed by clinical pharmacists on antibiotic utilisation, prophylaxis and antimicrobial resistance (AMR).

DESIGN

This was a retrospective observational study of trends in antibiotic use and AMR in the context of AMS.

SETTING

Beijing Chaoyang Hospital, a 1400-bed tertiary hospital, in China.

DATA AND PARTICIPANTS

Antibiotic prescriptions from 820 doctors included all outpatients (n=17 766 637) and inpatients (n=376 627) during 2010-2016. Bacterial resistance data were from all inpatients (n=350 699) during 2011-2016.

INTERVENTIONS

Multiaspect intervention measures were implemented by clinical pharmacists (13 persons), for example, formulating the activity programme and performance management, advising on antibacterial prescriptions and training.

OUTCOME MEASURES

The proportion of antibiotic prescriptions among outpatients and inpatients, intensity of consumption in defined daily dose (DDD)/100 bed-days, antibiotic prophylaxis in type I incision operations and resistance rates of Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa were retrospectively analysed.

RESULTS

The proportion of antibiotic prescriptions decreased in outpatients (from 19.38% to 13.21%) and in inpatients (from 64.34% to 34.65%), the intensity of consumption dropped from 102.46 to 37.38 DDD/100 bed-days. The proportion of antibiotic prophylaxis decreased from 98.94% to 18.93%. The proportion of rational timing of initial dose increased from 71.11% to 96.74%, the proportion of rational duration rose from 2.84% to 42.63%. Time series analysis demonstrated the resistance rates of E. coli and P. aeruginosa to fluoroquinolones decreased, the incidence rate of methicillin-resistant Staphylococcus aureus also decreased, whereas the resistance rates of E. coli and K. pneumoniae to carbapenems increased. The antibiotic use was partly positively correlated with AMR.

CONCLUSIONS

AMS had an important role in reducing antibiotic use and surgical antibiotic prophylaxis. The AMR was positively correlated with antibiotic consumption to some extent.

Phenotypic and genotypic characterization of multi-drug-resistant Escherichia coli isolates harboring blaCTX-M group extended-spectrum β-lactamases recovered from pediatric patients in Shenzhen, southern China

Aims and Objectives: The emergence and spread of extended-spectrum β-lactamases (ESBLs) particularly CTX-M producing multi-drug-resistant (MDR) Escherichia coli (E. coli) is one of the greatest challenges for community health globally. The study investigated the phenotypic and genotypic characteristics of ESBLs-producing E. coli recovered from pediatric patients from Shenzhen Children’s Hospital, China.

Materials and methods: Present study, a total of 2,670 isolates of E. coli were collected from Shenzhen Children’s Hospital, China of which 950 were ESBLs producer. ESBLs production was confirmed by using the combination disc diffusion method, and antimicrobial susceptibility test was detected. In addition, β-lactamase-producing genes and co-existence of carbapenem/colistin resistance genes were determined by PCR assay and sequencing. The diversity and phylogenetic relationship were determined by multi-locus sequence typing method.

Results: Thirty-five percent (n=950) prevalence of ESBLs-producing E. coli we reported in Shenzhen, China of which 50 ESBLs producing E. coli were randomly selected for a further characterization. All 50 ESBLs- producing E. coli isolates revealed MDR phenotype and 100% were resistant to Ampicillin/sulbactam, Ampicillin, Cefazolin, and Ceftriaxone. All 50 ESBLs producers harbored at least one type of β-lactamase gene particular bla_CTX-M. The PCR and sequencing revealed the most common CTX-M subtype was bla_CTX-M-15 (n=18), followed by bla_CTX-M-14 (n=16), bla_CTX-M-90 (n=9), bla_CTX-M-55 (n=3), bla_CTX-M-27, bla_CTX-M-101, and bla_CTX-M-211 each (n=1). Co-existence of bla_CTX-M with bla_TEM, bla_SHV, bla_GES, and bla_VEB was detected in few isolates. Among identified sequence types, ST131 (12%) was more dominant in ESBLs-producing E. coli. Phylogenetic group A was the most prominent group among the ESBLs-producing E. coli based on multiplex PCR.

Conclusion: Our study shows the prevalence of bla_CTX-M gene in ESBLs-producing E. coli in pediatric patients in Shenzhen, China. We highlight the importance to monitor the emergence and trends of ESBLs-producing isolates in a pediatric healthcare setting.

Antimicrobial Activity of Omadacycline Tested against Clinical Bacterial Isolates from Hospitals in Mainland China, Hong Kong, and Taiwan: Results from the SENTRY Antimicrobial Surveillance Program (2013 to 2016)

Omadacycline is a derivative of minocycline and the first agent of the aminomethylcycline class. A total of 3,282 organisms (1 per patient) were consecutively collected from patients hospitalized in China (including Hong Kong) and Taiwan. Susceptibility testing was performed by broth microdilution methods in a central laboratory (JMI Laboratories). The collection included Gram-positive and Gram-negative organisms from patients with pneumonia, bloodstream, skin, community-acquired respiratory, and other infections. Omadacycline was very potent against Staphylococcus aureus (n = 689; MIC50/90, 0.12/0.25 mg/liter), including methicillin-resistant Staphylococcus aureus (MRSA; n = 299; MIC50/90, 0.12/0.5 mg/liter), and had similar activity across geographic regions. Omadacycline was very active against Streptococcus pneumoniae (highest MIC, 0.25 mg/liter), β-hemolytic streptococci (highest MIC, 1 mg/liter), viridans group streptococci (highest MIC, 0.25 mg/liter), and Enterococcus spp. (highest MIC, 0.5 mg/liter) from all geographic regions. Overall, 53.8% of S. pneumoniae isolates were penicillin resistant (penicillin MIC, ≥2 mg/liter) and 10.7% of enterococci (21.2% among E. faecium isolates) were vancomycin resistant. Omadacycline was active against Haemophilus influenzae (MIC50/90, 0.5/1 mg/liter) regardless of β-lactamase production and was active against Moraxella catarrhalis (MIC50/90, ≤0.12/0.25 mg/liter). Against Enterobacteriaceae, omadacycline was most active against Escherichia coli (MIC50/90, 1/2 mg/liter), Klebsiella oxytoca (MIC50/90, 1/4 mg/liter), and Enterobacter cloacae (MIC50/90, 2/4 mg/liter). Omadacycline had potent in vitro activity against Gram-positive and Gram-negative pathogens isolated from China and Taiwan and retained activity against problem pathogens, such as MRSA, vancomycin-resistant enterococci (VRE), penicillin-resistant S. pneumoniae (PRSPN), and extended-spectrum β-lactamase-producing E. coli The observed MIC profile in Chinese isolates was very similar to that seen in the U.S. and European surveillance studies.

Assessing Molecular Epidemiology of Carbapenem-resistant Klebsiella pneumoniae (CR-KP) with MLST and MALDI-TOF in Central China

Carbapenem-resistant K. pneumoniae (CR-KP) posts significant public health challenge worldwide. The aim of this study is to assess clinical characteristics and molecular epidemiology of CR-KP infections with Multilocus sequence typing (MLST) and Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF) in Central China. A total of 71 CR-KP isolates were recovered in a teaching hospital from October 2014 to December 2015. Among all CR-KP isolates, 73.2% (52) produced K. pneumoniae carbapenemases-2 (KPC-2). Eighteen ST types were identified by MLST, among these ST types, forty-seven isolates belonged to ST11 type, which was the predominant outbreak strain in China, and most ST11 isolates produced KPC-2. Eleven mass spectrometry (MS) types were identified by MALDI-TOF MS analysis, 53.5% isolates were MS4 and MS6, which matched with ST11 in MLST analysis. CR-KP infection was associated with increased medical cost and longer hospitalization. Therefore, we found that KPC-2-producing ST11 (MS4 and MS6) CR-KP isolates were the predominant clone identified by MLST and MALDI-TOF, and CR-KP infection was associated with increased hospital costs and longer hospitalization.

Bacteria and Antibiotic Resistance Genes (ARGs) in PM2.5 from China: Implications for Human Exposure

Airborne transmission is one of the environmental dissemination pathways of antibiotic resistance genes (ARGs), and has critical implications for human exposure through inhalation. In this study, we focused on three regions of China to reveal some unique spatiotemporal features of airborne bacteria and ARGs in fine aerosols (PM_2.5): (1) greater seasonal variations in the abundance of bacteria and ARGs in temperate urban Beijing than in the subtropical urban areas of the Yangtze River Delta (YRD) and Pearl River Delta (PRD) regions, with regional disparities in bacterial communities; (2) geographical fingerprints of ARG profiles independent of seasonal cycles and land-use gradients within each region; (3) region-independent associations between the targeted ARGs and limited bacterial genera; (4) common correlations between ARGs and mobile genetic elements (MGEs) across regions; and (5) PM_2.5 at the higher end of ARG enrichment across various environmental and human media. The spatiotemporally differentiated bacterial communities and ARG abundances, and the compositions, mobility, and potential hosts of ARGs in the atmosphere have strong implications for human inhalational exposure over spatiotemporal scales. By comparing other contributing pathways for the intake of ARGs (e.g., drinking water and food ingestion) in China and the U.S.A., we identified the region-specific importance of inhalation in China as well as country-specific exposure scenarios. Our study thus highlights the significance of inhalation as an integral part of the aggregate exposure pathways of environmentally disseminated ARGs, which, in turn, may help in the formulation of adaptive strategies to mitigate the exposure risks in China and beyond.

Antimicrobial resistance profiles of 5 common bovine mastitis pathogens in large Chinese dairy herds

The prevalence of antimicrobial resistance (AMR) is increasing in human and animal pathogens, becoming a concern worldwide. However, prevalence and characteristics of AMR of bovine mastitis pathogens in large Chinese dairy herds are still unclear. Therefore, our objective was to determine the AMR profile of bacteria isolated from clinical mastitis in large (>500 cows) Chinese dairy herds. A total of 541 isolates of the 5 most common species, Staphylococcus aureus (n = 103), non-aureus staphylococci (NAS; n = 107), Streptococcus species (n = 101), Klebsiella species (n = 130), and Escherichia coli (n = 100), isolated from bovine clinical mastitis on 45 dairy farms located in 10 provinces of China were included. Presence of AMR was determined by minimum inhibitory concentrations using the microdilution method. Prevalence of multidrug resistance (resistance to >2 antimicrobials) was 27% (148/541). A very wide distribution of minimum inhibitory concentrations was screened in all isolates, including Staph. aureus isolates, which were resistant to penicillin (66%). In addition, NAS (30%) were more resistant than Staph. aureus to oxacillin (84%), penicillin (62%), tetracycline (34%), and clindamycin (33%). Prevalence of resistance to tetracycline was high (59%) in Streptococcus spp. Additionally, prevalence of resistance of both E. coli and Klebsiella spp. was high to amoxicillin/clavulanate potassium (81 and 38%, respectively), followed by tetracycline (only Klebsiella spp. 32%). A high proportion (27%) of isolates were multidrug resistant; the most frequent combinations were clindamycin-cefalexin-tetracycline or enrofloxacin-cefalexin-penicillin patterns for Staph. aureus; enrofloxacin-oxacillin-penicillin-tetracycline patterns for NAS; clindamycin-enrofloxacin-tetracycline patterns for Streptococcus spp.; amoxicillin/clavulanate potassium-ceftiofur-polymyxin B patterns for Klebsiella spp.; and amoxicillin/clavulanate potassium-ceftiofur-polymyxin B patterns for E. coli. Resistance for 4 kinds of antimicrobials highly critical for human medicine, including daptomycin, vancomycin, imipenem, and polymyxin B, ranged from 0 to 24%. In conclusion, prevalence of AMR in mastitis pathogens was high on large Chinese dairy farms, potentially jeopardizing both antimicrobial efficacy and public health. Results of this study highlighted the need for improvements in antimicrobial stewardship and infection control programs in large Chinese dairy farms to reduce emergence of AMR.

Prevalence of macrolide resistance in Treponema pallidum is associated with macrolide consumption

We hypothesized that the large global variations in the prevalence of macrolide resistance in Treponema pallidum are related to differences in population-level macrolide consumption. The hypothesis was tested by, at a country-level, regressing the peak prevalence of macrolide resistance against the national macrolide consumption in the year prior to this, controlling for the year of the resistance prevalence estimate. A strong association was found between the per capita consumption of macrolides and macrolide resistance (coefficient 0.7, 95 % confidence interval 0.2-0.12, P=0.009).

Prevalence and Characterization of Staphylococcus aureus Isolated From Women and Children in Guangzhou, China

The prevalent Staphylococcus aureus clones and antibiotic susceptibility profiles are known to change dynamically and geographically; however, recent S. aureus strains causing infections in women and children in China have not been characterized. In this study, we analyzed the molecular epidemiology and antimicrobial resistance of S. aureus isolated from patients in four centers for women and children in Guangzhou, China. In total, 131 S. aureus isolates (100 from children and 31 from women) were analyzed by spa typing, multi-locus sequence typing, virulence gene and antimicrobial resistance profiling, staphylococcal chromosomal cassette mec typing, and mutation analyses of rpoB. A total of 58 spa types, 27 sequence types (STs), and 10 clonal complexes (CCs) were identified. While CC59 (ST59-IV, 48.8%; ST338-III, 35.7%) and CC45 (ST45-IV, 100%) were the major clones (84.4%) among MRSA isolates, CC5 (ST188, 24.3%; ST1, 21.6%) and CC398 (ST398, 70%) were the major ones (70.1%) among MSSA isolates. ST338-MRSA-III mostly found in pus but hardly in respiratory tract samples while ST45-MRSA-IV was on the opposite, even though they both found in blood and cerebrospinal fluid sample frequently. Staphylococcal enterotoxin genes seb-seq-sek were strongly associated with ST59 and ST338, while sec was associated with ST45, ST121, ST22, and ST30. All ST338, ST1232, and SCCmec III isolates carried lukF/S-PV genes. A total of 80% of ST338 isolates were resistant to erythromycin, clindamycin, and tetracycline. All ST45 isolates exhibited intermediate or complete resistance to rifampicin. In total, 481 HIS/ASN mutations in rpoB were found in rifampicin-resistant or intermediate-resistant isolates. ST338-III and ST45-IV emerged as two of three major clones in MRSA isolates from women and children in Guangzhou, China, though ST59-MRSA-IV remained the most prevalent MRSA clone. Clonal distribution of S. aureus varied, depending on the specimen source. Virulence genes and antibiograms were closely associated with the clonal lineage. These results clarified the molecular epidemiology of S. aureus from women and children in Guangzhou, China, and provide critical information for the control and treatment of S. aureus infections.