Rectal carriage of extended-spectrum beta-lactamase-producing gram-negative bacilli in community settings in Madagascar

Socioeconomic status and the risk for colonization or infection with priority bacterial pathogens: a global evidence map

Low socioeconomic status (SES) is thought to exacerbate risks for bacterial infections, but global evidence for this relationship has not been synthesized. We systematically reviewed the literature for studies describing participants' SES and their risk of colonization or community-acquired infection with priority bacterial pathogens. Fifty studies from 14 countries reported outcomes by participants' education, healthcare access, income, residential crowding, SES deprivation score, urbanicity, or sanitation access. Low educational attainment, lower than average income levels, lack of healthcare access, residential crowding, and high deprivation were generally associated with higher risks of colonization or infection. There is limited research on these outcomes in low- and middle-income countries (LMICs) and conflicting findings regarding the effects of urbanicity. Only a fraction of studies investigating pathogen colonization and infection reported data stratified by participants' SES. Future studies should report stratified data to improve understanding of the complex interplay between SES and health, especially in LMICs.

ESBL-Type and AmpC-Type Beta-Lactamases in Third Generation Cephalosporin-Resistant Enterobacterales Isolated from Animal Feces in Madagascar

Third generation cephalosporin-resistant (3GCR) Enterobacterales are known to be prevalent in Madagascar, with high colonization or infection rates in particular in Madagascan patients. Extended spectrum beta-lactamases (ESBLs) have been reported to be the predominant underlying resistance mechanism in human isolates. So far, little is known on antimicrobial resistance and its molecular determinants in Enterobacterales and other bacteria causing enteric colonization of Madagascan wild animals. To address this topic, swabs from 49 animal stool droppings were collected in the Madagascan Tsimanapesotsa National Park and assessed by cultural growth of bacterial microorganisms on elective media. In addition to 7 Acinetobacter spp., a total of 31 Enterobacterales growing on elective agar for Enterobacterales could be isolated and subjected to whole genome sequencing. Enterobacter spp. was the most frequently isolated genus, and AmpC-type beta-lactamases were the quantitatively dominating molecular resistance mechanism. In contrast, the blaCTX-M-15 gene, which has repeatedly been associated with 3GC-resistance in Madagascan Enterobacterales from humans, was detected in a single Escherichia coli isolate only. The identification of the fosfomycin-resistance gene fosA in a high proportion of isolates is concerning, as fosfomycin is increasingly used to treat infections caused by multidrug-resistant bacteria. In conclusion, the proof-of-principle assessment indicated a high colonization rate of resistant bacteria in stool droppings of Madagascan wild animals with a particular focus on 3GCR Enterobacterales. Future studies should confirm these preliminary results in a more systematic way and assess the molecular relationship of animal and human isolates to identify potential routes of transmission.

Risk factors for extended-spectrum beta-lactamase (ESBL)-producing E. coli carriage among children in a food animal-producing region of Ecuador: A repeated measures observational study

BACKGROUND

The spread of antibiotic-resistant bacteria may be driven by human-animal-environment interactions, especially in regions with limited restrictions on antibiotic use, widespread food animal production, and free-roaming domestic animals. In this study, we aimed to identify risk factors related to commercial food animal production, small-scale or "backyard" food animal production, domestic animal ownership, and practices related to animal handling, waste disposal, and antibiotic use in Ecuadorian communities.

METHODS AND FINDINGS

We conducted a repeated measures study from 2018 to 2021 in 7 semirural parishes of Quito, Ecuador to identify determinants of third-generation cephalosporin-resistant E. coli (3GCR-EC) and extended-spectrum beta-lactamase E. coli (ESBL-EC) in children. We collected 1,699 fecal samples from 600 children and 1,871 domestic animal fecal samples from 376 of the same households at up to 5 time points per household over the 3-year study period. We used multivariable log-binomial regression models to estimate relative risks (RR) of 3GCR-EC and ESBL-EC carriage, adjusting for child sex and age, caregiver education, household wealth, and recent child antibiotic use. Risk factors for 3GCR-EC included living within 5 km of more than 5 commercial food animal operations (RR: 1.26; 95% confidence interval (CI): 1.10, 1.45; p-value: 0.001), household pig ownership (RR: 1.23; 95% CI: 1.02, 1.48; p-value: 0.030) and child pet contact (RR: 1.23; 95% CI: 1.09, 1.39; p-value: 0.001). Risk factors for ESBL-EC were dog ownership (RR: 1.35; 95% CI: 1.00, 1.83; p-value: 0.053), child pet contact (RR: 1.54; 95% CI: 1.10, 2.16; p-value: 0.012), and placing animal feces on household land/crops (RR: 1.63; 95% CI: 1.09, 2.46; p-value: 0.019). The primary limitations of this study are the use of proxy and self-reported exposure measures and the use of a single beta-lactamase drug (ceftazidime with clavulanic acid) in combination disk diffusion tests for ESBL confirmation, potentially underestimating phenotypic ESBL production among cephalosporin-resistant E. coli isolates. To improve ESBL determination, it is recommended to use 2 combination disk diffusion tests (ceftazidime with clavulanic acid and cefotaxime with clavulanic acid) for ESBL confirmatory testing. Future studies should also characterize transmission pathways by assessing antibiotic resistance in commercial food animals and environmental reservoirs.

CONCLUSIONS

In this study, we observed an increase in enteric colonization of antibiotic-resistant bacteria among children with exposures to domestic animals and their waste in the household environment and children living in areas with a higher density of commercial food animal production operations.

High level of colonization with 3rd-generation cephalosporin-resistant Enterobacterales in African community settings, Ghana

A cross-sectional survey was conducted in eight Ghanaian communities to investigate the extent of intestinal colonization with 3^rd-generation cephalosporin-resistant Enterobacterales. The study collected faecal samples and corresponding lifestyle data from 736 healthy residents to assess the occurrence of cephalosporin-resistant Escherichia coli and Klebsiella pneumoniae, with a focus on genotypes of plasmid-mediated ESBLs, AmpCs, and carbapenemases. The results showed that 371 participants (50.4%) carried 3^rd-generation cephalosporin-resistant E. coli (n=362) and K. pneumoniae (n=9). Most of these were ESBL-producing E. coli (n=352, 94.9%), carrying CTX-M genes (96.0%, n=338/352), mostly for CTX-M-15 (98.9%, n=334/338). Nine participants (1.2%) carried AmpC-producing E. coli that harboured bla_DHA-1 or blaCMY-2 genes, and two participants (0.3%) each carried a carbapenem-resistant E. coli that harboured both bla_NDM-1 and bla_CMY-2. Quinolone-resistant O25b: ST131 E. coli were recovered from six participants (0.8%) and were all CTX-M-15 ESBL-producers. Having a household toilet facility was significantly associated with a reduced risk of intestinal colonization (adjusted odds ratio, 0.71; 95% CI, 0.48-0.99; P-value=0.0095) in multivariate analysis. These findings raise serious public health concerns, and effective control of the spread of antibiotic-resistant bacteria is possible by providing better sanitary conditions for communities.

Antibiotic resistance genes of public health importance in livestock and humans in an informal urban community in Nepal

Efforts to mitigate the increasing emergence of antimicrobial resistance (AMR) will benefit from a One Health perspective, as over half of animal antimicrobials are also considered medically important in humans, and AMR can be maintained in the environment. This is especially pertinent to low- and middle-income countries and in community settings, where an estimated 80% of all antibiotics are used. This study features AMR genes found among humans, animals, and water at an urban informal settlement in Nepal with intensifying livestock production. We sampled humans, chickens, ducks, swine, and water clustered by household, as well as rodents and shrews near dwellings, concurrently in time in July 2017 in southeastern Kathmandu along the Manohara river. Real-time qualitative PCR was performed to screen for 88 genes. Our results characterize the animal-human-environmental interfaces related to the occurrence of specific resistance genes (bla_SHV-1 (SHV(238G240E) strain), QnrS, ermC, tetA, tetB, aacC2, aadA1) associated with antibiotics of global health importance that comprise several drug classes, including aminoglycosides, beta-lactams, tetracyclines, macrolides, and fluoroquinolones. By characterizing risk factors across AMR genes of public health importance, this research highlights potential transmission pathways for further investigation and provides prioritization of community-based prevention and intervention efforts for disrupting AMR transmission of critically important antibiotics used in both humans and animals in Nepal.

Antibiotic resistance genes in the gut microbiota of mothers and linked neonates with or without sepsis from low- and middle-income countries

Early development of the microbiome has been shown to affect general health and physical development of the infant and, although some studies have been undertaken in high-income countries, there are few studies from low- and middle-income countries. As part of the BARNARDS study, we examined the rectal microbiota of 2,931 neonates (term used up to 60 d) with clinical signs of sepsis and of 15,217 mothers screening for bla_CTX-M-15, bla_NDM, bla_KPC and bla_OXA-48-like genes, which were detected in 56.1%, 18.5%, 0% and 4.1% of neonates’ rectal swabs and 47.1%, 4.6%, 0% and 1.6% of mothers’ rectal swabs, respectively. Carbapenemase-positive bacteria were identified by MALDI-TOF MS and showed a high diversity of bacterial species (57 distinct species/genera) which exhibited resistance to most of the antibiotics tested. Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae/E. cloacae complex, the most commonly found isolates, were subjected to whole-genome sequencing analysis and revealed close relationships between isolates from different samples, suggesting transmission of bacteria between neonates, and between neonates and mothers. Associations between the carriage of antimicrobial resistance genes (ARGs) and healthcare/environmental factors were identified, and the presence of ARGs was a predictor of neonatal sepsis and adverse birth outcomes.

Analysis of gut microbiota of mothers and its neonates—as part of the BARNARDS study—reveals associations between β-lactamase gene carriage and neonatal sepsis risk in low-income settings.

Prevalence and household risk factors for fecal carriage of ESBL-producing, sequence type 131, and extraintestinal pathogenic Escherichia coli among children in southern Taiwan

BACKGROUND

The rapidly increasing prevalence of antimicrobial-resistant Escherichia coli (E. coli) is a global concern. This study determined the prevalence and risk factors for the fecal carriage of drug-resistant E. coli and extraintestinal pathogenic E. coli (ExPEC) among children.

MATERIALS AND METHODS

In this prospective study, stool samples from children aged 0-18 years were obtained within three days of hospitalization between April 2016 and March 2019. E. coli were selected and tested for extended-spectrum β-lactamase (ESBL)-production and antimicrobial susceptibility. Multilocus sequence typing, blaCTX-M gene groups and ExPEC were determined using polymerase chain reactions. Questionnaires were recorded for risk factor analysis.

RESULTS

Among 179 E. coli isolates, 44.1% were multi-drug resistant, 20.7% produced ESBL, and 50.3% were ExPEC. Children carrying ESBL-producing E. coli were younger than those carrying non-ESBL strains. Several anthropogenic factors, including drinking water process, pork consumption, pets and household density might be associated with ESBL-producing E. coli, sequence type (ST) 131 E. coli, or ExPEC fecal carriage. Compared with families who live in less crowded houses, participants with pets had a similar trend of higher risks of ESBL-producing E. coli, ST131 E. coli, and ExPEC fecal carriage among those living in houses accommodating relatively more people.

CONCLUSIONS

Children accounted for a large proportion of instances of feces carrying ESBL E. coli. In addition to antimicrobial control for people and livestocks, avenues of exposure, such as drinking water, food, pets, household density, and socioeconomic deprivation might present potentially novel opportunities to reduce the burden of nonsusceptible E. coli and ExPEC.

Intestinal Carriage of Extended-spectrum β-lactamase and Carbapenemase-producing Enterobacteriaceae in Hemodialysis Patients

Background: Gastrointestinal colonization with resistant pathogens is significant because they could be easily transmitted to other hosts or spread to different microbiota through mobile genetic elements. Objectives: This study assessed the prevalence of fecal carriage of extended-spectrum β-lactamase-producing and carbapenemase-producing Enterobacteriaceae (ESBL-E and CPE, respectively) among hemodialysis patients and the factors affecting its occurrence in a hospital in Tehran. Methods: From January 2018 to May 2019, 150 hemodialysis patients referred to a hospital in Tehran were sampled in this study. Stool samples of the patients were diluted in saline and cultured on MacConkey agar plates containing cefotaxime, ceftazidime, imipenem, and meropenem discs. The clinical data were analyzed to identify the risk factors using a logistic regression model. Results: The colonization rate of ESBL-E was 48.6%, while only 2% of patients were identified as the carriers of CPE (3 of 150). A higher prevalence rate was obtained for intestinal carriage of ESBL-E among hemodialysis patients aged 18 to 42 years using multivariate analysis. The prevalence rate of multidrug-resistant isolates was 73.8%. The blaCTX-M1 gene was identified as the most prevalent ESBL gene. Among carbapenemase-encoding genes, blaKPC and blaoxa-48 were found in 12 and two isolates, respectively. Conclusions: These results demonstrated a high prevalence rate of ESBLs among hemodialysis patients, although this rate was low for carbapenemases. Therefore, more control measures should be taken in hospitals to prevent the spread of antibiotic resistance genes in healthcare settings.

Extended-Spectrum Beta-Lactamase- and Carbapenemase-Producing Enterobacteriaceae Family of Bacteria from Diarrheal Stool Samples in Northwest Ethiopia

Background

Resistance among the commensal flora is a serious threat because they are highly populated ecosystems like the gut, maybe a source of extraintestinal infections. Infections due to extended-spectrum beta-lactamase (ESBL)- and carbapenemase (CPM)-producing Enterobacteriaceae family of bacteria impose a major global issue because they are usually resistant to multiple antimicrobial agents. Data on the fecal ESBL- and CPM-producing group of bacteria in developing countries including Ethiopia are limited mainly due to resource constraints. Thus, this study aimed to determine the prevalence of multidrug-resistant (MDR)-, ESBL-, and CPM-producing Enterobacteriaceae family of bacteria from diarrheal stool samples at the University Hospital, Northwest Ethiopia.

Materials and Methods

A hospital-based cross-sectional study was conducted involving a total of 384 study participants having gastrointestinal complaints from January to April 2019. A diarrheal stool sample was aseptically collected and inoculated on a MacConkey agar plate. After getting pure colonies, biochemical and antimicrobial susceptibility testing was done following standard microbiological techniques. ESBL production was screened using ceftazidime and cefotaxime and confirmed using a combined disk diffusion test. Carbapenemases were screened by meropenem disk and confirmed by the modified carbapenem inactivation method. Data were checked, cleaned, and entered using Epi Info version 7.1 and transferred to SPSS version 20 for analysis.

Result

A total of 404 Enterobacteriaceae groups of bacteria were isolated from 384 diarrheal stool samples. The overall prevalence of fecal MDR-, ESBL-, and CPM-producing group of Enterobacteriaceae was 196 (48.5%), 66 (16.3%), and 4 (1%), respectively. Of the total ESBL-producing Enterobacteriaceae, E. coli (41/66 (62.1%)) and K. pneumoniae (18/66 (27.3%)) were the most predominant isolates. One half of CPE has been observed in Citrobacter species and the rest in E. coli (25%) and P. vulgaris (25%). Conclusion and Recommendation. Finding the high rate of ESBL-producing Enterobacteriaceae and CPE requires strict infection control measures and careful selection of empirical therapy in the study area. Therefore, active surveillance with large sample size and better infection prevention control is needed.

Prevalence, Risk Factors, and Genetic Characterization of Extended-Spectrum Beta-Lactamase Escherichia coli Isolated From Healthy Pregnant Women in Madagascar

Antimicrobial resistance is a major public health concern worldwide affecting humans, animals and the environment. However, data is lacking especially in developing countries. Thus, the World Health Organization developed a One-Health surveillance project called Tricycle focusing on the prevalence of ESBL-producing Escherichia coli in humans, animals, and the environment. Here we present the first results of the human community component of Tricycle in Madagascar. From July 2018 to April 2019, rectal swabs from 492 pregnant women from Antananarivo, Mahajanga, Ambatondrazaka, and Toamasina were tested for ESBL-E. coli carriage. Demographic, sociological and environmental risk factors were investigated, and E. coli isolates were characterized (antibiotic susceptibility, resistance and virulence genes, plasmids, and genomic diversity). ESBL-E. coli prevalence carriage in pregnant women was 34% varying from 12% (Toamasina) to 65% (Ambatondrazaka). The main risk factor associated with ESBL-E. coli carriage was the rainy season (OR = 2.9, 95% CI 1.3-5.6, p = 0.009). Whole genome sequencing was performed on 168 isolates from 144 participants. bla CTX-M-15 was the most frequent ESBL gene (86%). One isolate was resistant to carbapenems and carried the bla NDM-5 gene. Most isolates belonged to commensalism associated phylogenetic groups A, B1, and C (90%) and marginally to extra-intestinal virulence associated phylogenetic groups B2, D and F (10%). Multi locus sequence typing showed 67 different sequence types gathered in 17 clonal complexes (STc), the most frequent being STc10/phylogroup A (35%), followed distantly by the emerging STc155/phylogroup B1 (7%), STc38/phylogroup D (4%) and STc131/phylogroup B2 (3%). While a wide diversity of clones has been observed, SNP analysis revealed several genetically close isolates (n = 34/168) which suggests human-to-human transmissions. IncY plasmids were found with an unusual prevalence (23%), all carrying a bla CTX-M-15. Most of them (85%) showed substantial homology (≥85%) suggesting a dissemination of IncY ESBL plasmids in Madagascar. This large-scale study reveals a high prevalence of ESBL-E. coli among pregnant women in four cities in Madagascar associated with warmth and rainfall. It shows the great diversity of E. coli disseminating throughout the country but also transmission of specific clones and spread of plasmids. This highlights the urgent need of public-health interventions to control antibiotic resistance in the country.

Prevalence and patient related factors associated with Extended-Spectrum Beta-Lactamase producing Escherichia coli and Klebsiella pneumoniae carriage and infection among pediatric patients in Tanzania

Extended-Spectrum Beta-Lactamase (ESBL) producing Enterobacteriaceae (EPE) is increasing worldwide, though less documented in low-income settings. Here we determined the prevalence of EPE infection and carriage, and patient factors associated with EPE-carriage among pediatric patients in three health care levels in Tanzania. Between January and April 2016, 350 febrile children (median age 21 months) seeking care at a university or a regional referral hospital, or a health centre in Moshi municipality, Tanzania, were included. Socio-demographic characteristics were collected using a questionnaire. Rectal swabs and blood cultures were collected from all children (n = 350) and urinary samples from 259 children at admission. ESBL-phenotype and antimicrobial susceptibility were determined for Klebsiella pneumoniae (K. pneumoniae) and Escherichia coli (E. coli) isolates. Only one EPE case (E. coli) in blood and four in urine (one E. coli and three K. pneumoniae) were found, whereas (n = 90, 26%) of the children were colonized in feces (ESBL-E. coli; n = 76, ESBL-K. pneumoniae, n = 14). High resistance rates were seen in fecal ESBL-E. coli (n = 76) against trimethoprim-sulfamethoxazole (n = 69, 91%), gentamicin (n = 51, 67%), ciprofloxacin (n = 39, 51%) and chloramphenicol (n = 27, 35%) whereas most isolates were sensitive to amikacin (n = 71, 93%). Similar rates were seen for fecal ESBL-K. pneumoniae. Resistance to first line antibiotics were also very high in fecal E. coli not producing ESBL. No sociodemographic factor was associated with EPE-carriage. Children colonized with EPE were younger than 12 months (n = 43, 48%) and often treated with antibiotics (n = 40, 44%) in the previous two months. After adjustment for age children admitted to the intensive care unit had higher odds of EPE fecal carriage compared with those in the general wards (OR = 3.9, 95%CI = 1.4–10.4). Despite comparatively high rates of fecal EPE-carriage and previous antibiotic treatment, clinical EPE cases were rare in the febrile children. The very high resistant rates for the EPE and the non-ESBL producing E. coli to commonly used antibiotics are worrying and demand implementation of antibiotic stewardship programs in all levels of health care in Tanzania.

High prevalence of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae fecal carriage among children under five years in Addis Ababa, Ethiopia

Background

Extended-spectrum beta-lactamase (ESBL) producing bacteria present an ever-growing burden in the hospital and community settings. Data on the prevalence of ESBL fecal carriage remain scarce in Ethiopia. Therefore, this study aimed to determine the prevalence of ESBL producing Escherichia coli and Klebsiella pneumoniae fecal carriage among children under five years in Addis Ababa, Ethiopia.

Methods

A facility-based cross-sectional study was conducted from April to May 2017. A total of 269 fecal/rectal swab samples were cultured on MacConkey agar. All positive cultures were characterized by colony morphology, Gram stain, and standard biochemical tests. Further, bacteria identification, antimicrobial susceptibility testing, and phenotypic detection of ESBL production were performed using VITEK 2 Compact as per the instruction of the manufacturer. Socio-demographic and risk factors data were collected using questionnaires. Data were entered by EPI INFO version 7.2.1.0 and analyzed by SPSS version 20.

Results

The overall prevalence of ESBL-producing E. coli and K. pneumoniae was 17.1% (46/269; 95% CI: 12.9%–22.7%). A total of 47 isolates were ESBL-positive, of which, 83.0% were E. coli and 17.0% were K. pneumoniae. ESBL producing E. coli and K. pneumoniae isolates were also showed high levels of MDR (93.6%) and high rates of co-resistance to aminoglycosides, fluoroquinolones, and trimethoprim-sulfamethoxazole. However, all isolates were carbapenem susceptible. In the risk factors analysis, Children’s mothers who had lower educational level (primary school) (OR: 2.472, 95% CI: 1.323–4.618, P = 0.0062) and children who used tap water for drinking (OR: 1.714, 95% CI: 1.001–3.659, P = 0.048) were found to be significantly associated with higher ESBL fecal carriage.

Conclusions

In this study, the high prevalence rate of ESBL producing E. coli and K. pneumoniae fecal carriage and high level of multidrug resistance among ESBL producing E. coli and K. pneumoniae were demonstrated. This suggested that the necessity of routine screening of ESBL is crucial for the early detection and appropriate antibiotics selection for infection caused by ESBL producing pathogens.

Prevalence and Characterization of Extended-Spectrum Beta-Lactamase-Producing Enterobacteriaceae in Major Hospitals in Gabon

In Gabon, few data exist on extended-spectrum beta-lactamases-producing Enterobacteriaceae (ESBL-PE). This study investigated ESBL-PE prevalence and the associated resistance genes in clinical samples (n = 5,956) and anal swabs (n = 78) analyzed in eight hospitals and a medical analysis laboratory in Gabon from January 2016 to March 2018. Matrix-Assisted Laser Desorption Ionization-Time Of Flight (MALDI-TOF) mass spectrometry analysis identified 790 Enterobacteriaceae isolates (n = 712 clinical samples and n = 78 fecal samples). ESBL-PE prevalence (Müller-Hinton agar disk diffusion method and double-disk synergy test) was 11.8% (84/712) in clinical samples (15.5% from inpatients and 7.1% from outpatients; p < 0.05) and 16.7% (13/78) in carriage isolates. Most ESBL-PE were isolated from urine samples (46/84). In clinical and carriage ESBL-PE isolates, Escherichia coli was predominant (42.8% and 61.5%; phylogroups A, B1, B2, and D), followed by Klebsiella pneumoniae (41.7% and 23.1%). Multiplex PCR and bi-directional sequencing showed that CTX-M group 1 (blaCTX-M-15) was predominant in clinical and carriage ESBL-PE (94% and 92.3%) among which 85.7% and 92.3% also harbored one to three β-lactamase-encoding genes (blaTEM-1, blaOXA-1, or blaSHV-1). Resistance genes were detected in all hospitals in Gabon. ESBL-PE prevalence in Gabon has not reached alarming levels yet, but corrective and monitoring measures are needed to curb their emergence.

Use of probiotics to reduce infections and death and prevent colonization with extended-spectrum beta-lactamase (ESBL)-producing bacteria among newborn infants in Tanzania (ProRIDE Trial): study protocol for a randomized controlled clinical trial

BACKGROUND

Extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E) has emerged as an urgent global health threat and is by the World Health Organization ranked as priority 1 among pathogens in need of new treatment. Studies have shown high mortality in Tanzanian children with ESBL-E infections. Gut colonization of ESBL-E, which is a potential risk factor of ESBL-E infections, is reported to be very high among children in Tanzania. Probiotics may potentially reduce gut colonization of multidrug-resistant bacteria. However, there is limited data on whether probiotics may reduce ESBL-E carriage in infants. The ProRIDE Trial aims to evaluate whether the use of probiotics can reduce morbidity and mortality among infants in Haydom, Tanzania, and whether this effect is associated with a reduction in ESBL-E colonization and/or infections.

METHODS/DESIGN

This large randomized double-blinded placebo-controlled trial aims to recruit 2000 newborn infants at Haydom Lutheran Hospital and the surrounding area in the period of November 2020 to November 2021. Participants will be enrolled from days 0 to 3 after birth and randomized to receive probiotics or placebo for 4 weeks. Participants will be followed-up for 6 months, during which three visits will be made to collect clinical and demographic information, as well as rectal swabs and fecal samples which will be subjected to laboratory analysis. The primary composite outcome is the prevalence of death and/or hospitalization at 6 months of age.

DISCUSSION

As the use of probiotics may give a more favorable gut composition, and thereby improve health and reduce morbidity and mortality, the results may have implications for future therapy guidelines in Africa and internationally.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04172012. Registered on November 21, 2019.

Fecal carriage and factors associated with extended-spectrum β-lactamase-producing Enterobacteriaceae among pregnant women at the tertiary referral hospital, Tanzania

Background

Infections due to extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) are increasing worldwide. Evidence indicates that fecal carriage of ESBL-E in pregnancy predisposes women to potential life-threatening urinary tract infections and subsequently increasing the risk of neonatal infections. There is limited data regarding fecal carriage of ESBL-E and associated factors among pregnant women in Tanzania. We aimed to address the gap by determining the proportion of pregnant women with ESBL-E fecal carriage and identify the related factors.

Methodology

A hospital-based cross-sectional study was conducted at Muhimbili National Hospital in Dar es Salaam, Tanzania. A total of 182 pregnant women at the gestational age of 37 weeks and above were enrolled. Participants’ socio-demographic, clinical, and hygienic information were collected by using a well-structured questionnaire. Rectal swabs were collected and processed for isolation of ESBL-E. The extended-spectrum β-lactamase production and antibiotic susceptibility test (AST) were performed using a double-disc synergy test and Kirby-Bauer disc diffusion method, respectively.

Results

A total of 117 (64.3%) pregnant women were found to carry ESBL-E. Factors such as self-prescription of antibiotic medication during pregnancy, low education level, and toilet sharing were independently associated with ESBL-E fecal carriage. Five ESBL-E species that were isolated include Escherichia coli (84.6%), Klebsiella pneumoniae (8.9%), Klebsiella oxytoca (3.3%), Citrobacter spp. (1.6%), and Enterobacter spp. (1.6%). ESBL-E isolates demonstrated high resistance to aztreonam and sulphamethoxazole-trimethoprim.

Conclusion

This study has revealed a relatively high fecal carriage of ESBL-E among pregnant women, suggesting that there is a need for routine screening among that population. We recommend further studies to explore comprehensively the factors associated with high fecal carriage of ESBL-E in pregnancy and the potential transmission kinetics to their newborn babies.

Reunion Island, a sentinel territory for antimicrobial-resistant bacteria surveillance in the South-Western Indian Ocean: a retrospective survey using hospitalized patient screening, 2015-2017

Background

In 2015, antimicrobial resistance was identified as a public health priority for the South-Western Indian Ocean (SWIO) (i.e. Comoros, Madagascar, Mauritius, Mayotte (France), Reunion Island (France), and Seychelles). However, in 2020, colonization rates of antimicrobial-resistant bacteria (ARB) in human populations on most islands in SWIO were still not known and neither hospital nor community colonization rates had been estimated. The aim of this study was to estimate the prevalence of colonization of six ARB groups in hospitalized patients residing in the SWIO territories. The six groups comprise extended-spectrum betalactamase producing Enterobacteriaceae (ESBL-E), carbapenem-resistant Enterobacteriaceae (CRE), methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and both ceftazidime and/or imipenem-resistant Acinetobacter spp. (ACB), and ceftazidime and/or imipenem-resistant Pseudomonas spp. (PSA)).

Methods

Based on comprehensive hospital laboratory ARB screening data, we provide the first estimation of ARB colonization rates in hospitalized patients residing in SWIO (2015–2017). Using ARB colonization rates in Reunion Island (France) as the reference for estimating odds ratio, we identified at risk patients based on their territory of residence.

Results

The survey pointed to significantly higher overall ARB colonization rates in patients from Comoros, Madagascar, Mayotte, and Seychelles compared to Reunion Island as the reference. Extended-spectrum betalactamase producing Enterobacteriaceae was found to be the most common ARB group colonizing patients from SWIO territories. The highest MRSA colonization rates were observed in patients from Mayotte and Seychelles. Colonization by carbapenem-resistant Enterobacteriaceae (CRE) was highest in patients from Mauritius.

Conclusion

These results identify high ARB colonization rates in hospitalized patients from SWIO territories that require further investigation, particularly CRE in Mauritius and MRSA in Seychelles and Mayotte. This study is the first step toward the implementation of a broader regional ARB surveillance system.

Carriage and Acquisition of Extended-spectrum β-Lactamase-producing Enterobacterales Among Neonates Admitted to Hospital in Kilifi, Kenya

Background

Infections caused by extended-spectrum β-lactamase–producing Enterobacterales (ESBL-E) among hospitalized neonates in sub-Saharan Africa pose significant clinical challenges. Data on prevalence and acquisition of ESBL-E carriage among hospitalized neonates in the region are few, and risk factors for transmission are not clearly defined.

Methods

In a cohort study of consecutive neonatal admissions to Kilifi County Hospital from July 2013 through August 2014, we estimated ESBL-E carriage prevalence on admission using rectal swab cultures and identified risk factors using logistic regression. Using twice-weekly follow-up swabs, we estimated the incidence and identified risk factors for ESBL-E acquisition in hospital using Poisson regression.

Results

The prevalence of ESBL-E carriage at admission was 10% (59/569). Cesarean delivery, older neonatal age, and smaller household size were significant risk factors. Of the 510 infants admitted without ESBL-E carriage, 238 (55%) acquired carriage during their hospital stay. The incidence of acquisition was 21.4% (95% confidence interval, 19.0%–24.0%) per day. The rate was positively associated with the number of known neonatal ESBL-E carriers and with the total number of neonates on the same ward.

Conclusions

Carriage of ESBL-E was common among neonates on admission, and in-hospital acquisition was rapid. The dissemination and selection of ESBL-E appears to be driven by hospital exposures, operative delivery, and neonatal ward patient density. Further attention to infection control, patient crowding, and carriage surveillance is warranted.

Drivers of Antibiotic Resistance Transmissionin Low- and Middle-Income Countriesfrom a "One Health" Perspective-A Review

Antibiotic resistance is an ecosystem problem threatening the interrelated human-animalenvironmenthealth under the "One Health" framework. Resistant bacteria arising in onegeographical area can spread via cross-reservoir transmission to other areas worldwide either bydirect exposure or through the food chain and the environment. Drivers of antibiotic resistance arecomplex and multi-sectoral particularly in Lower- and Middle-income countries. These includeinappropriate socio-ecological behaviors; poverty; overcrowding; lack of surveillance systems; foodsupply chain safety issues; highly contaminated waste effluents; and loose rules and regulations. Inorder to examine the drivers of antibiotic resistance from a "one health" perspective, a literaturereview was conducted on three databases including PubMed, Medline and Google Scholar. A totalof 485 studies of potential relevance were selected, out of which 182 were included in this review.Results have shown that the aforementioned market failures are the leading cause for the negativeexternality of antibiotic resistance that extends in scope from the individual to the global ecosystem.Incremental and sustainable global actions can make the change, however, the problem willcontinue to prevail if governments do not prioritize the "One health" approach and if individual'saccountability is still denied in a world struggling with profound socio-economic problems.

Gut mucosal colonisation with extended-spectrum beta-lactamase producing Enterobacteriaceae in sub-Saharan Africa: a systematic review and meta-analysis

Background: Extended-spectrum beta-lactamase producing Enterobacteriaceae (ESBL-E) threaten human health; and, in areas of sub-Saharan Africa (sSA) where carbapenems are not available, may render ESBL-E infections untreatable. Gut mucosal colonisation probably occurs before infection, making prevention of colonisation an attractive target for intervention, but the epidemiology of ESBL-E in sSA is poorly described.

Objectives: Describe ESBL-E colonisation prevalence in sSA and risk factors associated with colonisation.

Methods: Studies included were prospective cross-sectional or cohort studies reporting gut mucosal ESBL-E colonisation in any population in sSA. We searched PubMed and Scopus on 18 December 2018. We summarise the range of prevalence across sites and tabulated risk factors for colonisation. The protocol was registered (Prospero ID CRD42019123559).

Results: From 2975 abstracts we identified 32 studies including a total of 8619 participants from a range of countries and settings. Six studies were longitudinal; no longitudinal studies followed patients beyond hospital discharge.  Prevalence varied between 5 and 84% with a median of 31%, with a relationship to setting: pooled ESBL-E colonisation in community studies was 18% (95% CI 12 to 28, 12 studies); in studies recruiting people at admission to hospital colonisation was 32% (95% CI 24 to 41% 8 studies); and for inpatients, colonisation was 55% (95% CI 49 to 60%, 7 studies). Antimicrobial use was associated with increased risk of ESBL-E colonisation, and protected water sources or water treatment by boiling may reduce risk.

Conclusions: ESBL-E colonisation is common in sSA, but how people become carriers and why is not well understood. To inform the design of interventions to interrupt transmission in this setting requires longitudinal, community studies.

Gut mucosal colonisation with extended-spectrum beta-lactamase producing Enterobacteriaceae in sub-Saharan Africa: a systematic review and meta-analysis

Background: Extended-spectrum beta-lactamase producing Enterobacteriaceae (ESBL-E) threaten human health; and, in areas of sub-Saharan Africa (sSA) where carbapenems are not available, may render ESBL-E infections untreatable. Gut mucosal colonisation probably occurs before infection, making prevention of colonisation an attractive target for intervention, but the epidemiology of ESBL-E in sSA is poorly described. Objectives: Describe ESBL-E colonisation prevalence in sSA and risk factors associated with colonisation. Methods: Studies included were prospective cross-sectional or cohort studies reporting gut mucosal ESBL-E colonisation in any population in sSA. We searched PubMed and Scopus on 18 December 2018. We summarise the range of prevalence across sites and tabulated risk factors for colonisation. The protocol was registered (Prospero ID CRD42019123559). Results: From 2975 abstracts we identified 32 studies including a total of 8619 participants from a range of countries and settings. Six studies were longitudinal; no longitudinal studies followed patients beyond hospital discharge.  Prevalence varied between 5 and 84% with a median of 31%, with a relationship to setting: pooled ESBL-E colonisation in community studies was 18% (95% CI 12 to 28, 12 studies); in studies recruiting people at admission to hospital colonisation was 32% (95% CI 24 to 41% 8 studies); and for inpatients, colonisation was 55% (95% CI 49 to 60%, 7 studies). Antimicrobial use was associated with increased risk of ESBL-E colonisation, and protected water sources or water treatment by boiling may reduce risk. Conclusions: ESBL-E colonisation is common in sSA, but how people become carriers and why is not well understood. To inform the design of interventions to interrupt transmission in this setting requires longitudinal, community studies.

Global distribution and current research of AmpC beta-lactamase genes in aquatic environments: A systematic review

AmpC beta-lactamase genes are some of the most common antibiotic resistance genes and require special attention once they have become mobilised. The detection of these genes is well documented in clinical settings. However, there is insufficient knowledge of both plasmid and genomic AmpC genes in aquatic environments. This systematic review aimed to determine the extent of the knowledge gap in the literature regarding the prevalence of AmpC beta-lactamase genes in aquatic systems. Using selected criteria, a total of 27 databases were searched for applicable peer-reviewed journal articles. No date and language restrictions were applied. Journal articles that highlighted the detection of AmpC beta-lactamase genes in environmental aquatic systems, including wastewater treatment plants, were included. Of the 950 literature sources that were identified, 50 were selected for full text analysis based on predetermined criteria. Studies on AmpC genes detection were traced in 23 countries. These studies focused on surface water (24), wastewater (17), sea water (4) and both surface and wastewater (5). Most studies did not specifically aim to detect AmpC genes, but to detect antibiotic resistance genes in general. Presently no surveillance protocols, standardised detection methods or environmental limits exist for these genes and, due to a paucity of research in this field, it is unlikely that such systems will be implemented in the near future. The implications and dynamics of AmpC genes in aquatic systems remain unclear and require intense research to ensure the sustainability of environmental systems and human health.

Human, animal and environmental contributors to antibiotic resistance in low-resource settings: integrating behavioural, epidemiological and One Health approaches

Antibiotic resistance (ABR) is recognized as a One Health challenge because of the rapid emergence and dissemination of resistant bacteria and genes among humans, animals and the environment on a global scale. However, there is a paucity of research assessing ABR contemporaneously in humans, animals and the environment in low-resource settings. This critical review seeks to identify the extent of One Health research on ABR in low- and middle-income countries (LMICs). Existing research has highlighted hotspots for environmental contamination; food-animal production systems that are likely to harbour reservoirs or promote transmission of ABR as well as high and increasing human rates of colonization with ABR commensal bacteria such as Escherichia coli However, very few studies have integrated all three components of the One Health spectrum to understand the dynamics of transmission and the prevalence of community-acquired resistance in humans and animals. Microbiological, epidemiological and social science research is needed at community and population levels across the One Health spectrum in order to fill the large gaps in knowledge of ABR in low-resource settings.

Epidemiology of Early-onset Bacterial Neonatal Infections in Madagascar

BACKGROUND

Little is known about early-onset neonatal bacterial infections (EONBI) in Madagascar. Our aim was to determine their epidemiology to improve their management.

METHODS

Inborn neonates at risk for EONBI and admitted in the neonatal unit of 2 tertiary hospitals in Antananarivo, Madagascar, were included in a prospective study from April 2012 to March 2013. Using a clinical algorithm, blood culture, gastric fluid culture and C-reactive protein dosage were performed in newborns at high risk of infection, that is, peri partum fever, prematurity <35 weeks' gestation or birth weight <2000 g, or presenting with clinical signs of infection. EONBI was defined as a bacteremia occurring within the first week of life.

RESULTS

Among 307 neonates, 75 (24.4%) had an EONBI caused by 1 (n = 59) or 2 (n = 16) bacteria (91 isolates). Gram-negative bacteria were predominant (n = 62, 82.7%), including Enterobacter cloacae (n = 26), Klebsiella pneumoniae (n = 14), Escherichia coli (n = 7) and Proteus mirabilis (n = 2). Group B Streptococcus, Acinetobacter baumanii and Enterococcus sp. represented 3.6%, 8.2% and 12.1% of the isolates, respectively. All E. cloacae and 12/14 (85.7%) K. pneumoniae were extended-spectrum β-lactamase producers. At all, 41/91 (45.1%) bacteria were multidrug-resistant (MDR) and 34/75 (45.3%) newborns had an EONBI caused by an MDR bacteria. Neonatal asphyxia was the only factor associated with multidrug resistance (odds ratio: 4.52; CI: 1.20-16.94; P = 0.025). The EONBI-related mortality (n = 20/75, 26.7%) rose up to 38.2% (n = 13/34) in case of MDR bacteria.

CONCLUSIONS

The epidemiology of EONBIs in Madagascar is comparable to that found in many low-income countries. Prevention, including improvement of hygiene during resuscitation for neonatal asphyxia, is likely to be more effective in reducing EONBI-related morbidity and mortality than using new antibiotics to counter resistance.

Bacteria Producing Extended Spectrum β-lactamases (ESBLs) in Hospitalized Patients: Prevalence, Antimicrobial Resistance Pattern and its Main Determinants

Background and Objective:

There is a growing concern regarding the lack of new antibiotics, especially for multidrug- resistant bacteria that produce Extended Spectrum β-Lactamases (ESBLs). The present study aims to assess the preva- lence of bacteria producing ESBLs, their antimicrobial resistance pattern, and its main determinants among hospitalized patients.

Methods:

The study population included 383 consecutive patients with a definitive diagnosis of urinary tract infection (UTI). All eligible subjects for the study had a positive culture for gram-negative microorganisms in urine specimens. ESBL producing isolates were characterized phenotypically for ESBL production using the double disc synergy test.

Results:

In total, 383 specimens were assessed, among which 212 (55.4%) were related to bacteria producing ESBLs (ESBL+). Of those with ESBL + infections, 65.5% were sourced from catheters (as hospital-associated UTIs), and 35.5% were categorized as community-associated UTIs. In the group consisting of bacteria producing ESBLs, the high- est sensitivity was observed with Imipenem (72.2%), while the highest resistance was revealed with ceftriaxone (100%).

Conclusion:

We have shown that our community faces a high prevalence of bacteria producing ESBLs, mostly sourced from the catheterization of hospitalized patients. The highest bacterial sensitivity was observed with Imipenem, nitrofu- rantoin, and amikacin, while the highest resistance was found with ceftriaxone and cotrimoxazole, suggesting the inef- fectiveness of using the two latter antibiotics for eradicating these bacterial infections. On the other hand, a history of urinary catheterization and previous hospitalization were two main determinants of their presence, a finding which em- phasizes the importance of avoiding catheterization and hospitalization of patients with UTIs without proper indications.

Faecal colonization of E. coli and Klebsiella spp. producing extended-spectrum beta-lactamases and plasmid-mediated AmpC in Mozambican university students

Background

In recent years, the world has seen a surge in Enterobacteriaceae resistant to broad-spectrum beta-lactam antibiotics due to the production of extended-spectrum beta-lactamases (ESBLs) or plasmid-mediated AmpC (pAmpC) enzymes. Data on the epidemiology of cephalosporin-resistant Enterobacteriaceae in Sub-Saharan Africa are still limited.

Methods

Two hundred seventy-five non-repetitive stool samples were collected from Mozambican university students of both sexes. Samples were cultured on MacConkey agar with and without ceftriaxone (1 mg/L) for selection of third-generation cephalosporin-resistant isolates, which were subjected to antimicrobial susceptibility testing by disc diffusion, characterization of resistance genes by PCR and ERIC-PCR analysis for strain clonality.

Results

Among the 275 students, 55 (20%) carried a total of 56 E. coli (n = 35) and Klebsiella spp. (n = 21) isolates resistant to ceftriaxone and phenotypically positive for ESBL- and/or pAmpC-production. Forty-three percent of the isolates (24/56) contained only ESBL genes, 11% (6/56) only pAmpC genes, and 36% (20/56) both ESBL and pAmpC genes. The remaining six isolates were negative for the CTX-M/pAmpC genes included in the test panel. E. coli and Klebsiella spp. combined demonstrated 70% resistance to tetracycline and co-trimoxazole, 63% to ceftazidime and 34% to ciprofloxacin. In total, 89% of ESBL/pAmpC-positive isolates were defined as multi-resistant by being resistant to three or more antibiotic classes. ERIC-PCR fingerprinting demonstrated low similarity among isolates. None of the participants reported recent hospitalization and just 12.5% had taken antibiotics 3 months prior to the study.

Conclusion

This study demonstrated 20% colonization with multi-resistant E. coli and Klebsiella spp. among Mozambican students with a diversity of ESBL and pAmpC genes. Colonization was not related to prior hospitalization or antimicrobial consumption.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3154-1) contains supplementary material, which is available to authorized users.

High carriage rate of extended-spectrum beta-lactamase-producing Enterobacteriaceae among patients admitted for surgery in Tanzanian hospitals with a low rate of endogenous surgical site infections

INTRODUCTION

Despite the high reported rates of surgical site infections (SSIs) caused by extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae (EPE) in low-income countries, including Tanzania, the role of EPE carriage in subsequent occurrence of SSIs is not known. This study investigated the rates of EPE carriage among surgical patients at the time of admission and discharge, and linked EPE genotype with SSIs.

METHODS

EPE were confirmed among isolates from rectal and wound/pus swabs using VITEK-2. Polymerase chain reaction and sequencing were performed to detect beta-lactamase genes. Multi-locus sequence typing was used to determine the genotypes of EPE isolates.

RESULTS

Among 930 patients enrolled, EPE carriage was significantly higher on discharge than admission (36.4% vs 23.7%, P<0.001). Of 272 patients who tested negative on admission, 78 (28.7%) acquired EPE during hospitalization. History of hospital stay within the previous three months was an independent predictor of EPE acquisition [hazard ratio 2, 95% confidence interval (CI) 1.04-3.98, P=0.038]. Of the 536 patients who were successfully followed-up after surgery, 78 (14.6%, 95% CI 11.6-17.5) developed SSIs. Of 57 SSIs investigated, 33 (58%) were caused by enteric Gram-negative bacteria, of which 63.6% (21/33) were EPE. Escherichia coli sequence type (ST)131 pandemic clone and Klebsiella pneumoniae ST391 predominated among wound isolates. The bla_CTX-M-15 gene was detected in 37 (97.3%) of 38 ESBL isolates. Male sex was an independent predictor of SSI (odds ratio 2.92, 95% CI 1.73-4.91, P<0.001).

CONCLUSION

These findings warrant implementation of strict infection control measures, antimicrobial stewardship and exploration of the transmission dynamics of EPE in surgical wards.

Acquisition of extended spectrum beta-lactamase-producing enterobacteriaceae in neonates: A community based cohort in Madagascar

In low and middle income countries (LMICs), where the burden of neonatal sepsis is the highest, the spread of extended spectrum beta-lactamase-producing enterobacteriaceae (ESBL-PE) in the community, potentially contributing to the neonatal mortality, is a public health concern. Data regarding the acquisition of ESBL-PE during the neonatal period are scarce. The routes of transmission are not well defined and particularly the possible key role played by pregnant women. This study aimed to understand the neonatal acquisition of ESBL-PE in the community in Madagascar. The study was conducted in urban and semi-rural areas. Newborns were included at birth and followed-up during their first month of life. Maternal stool samples at delivery and six stool samples in each infant were collected to screen for ESBL-PE. A Cox proportional hazards model was performed to identify factors associated with the first ESBL-PE acquisition. The incidence rate of ESBL-PE acquisition was 10.4 cases/1000 newborn-days [95% CI: 8.0–13.4 cases per 1000 newborn-days]. Of the 83 ESBL-PE isolates identified, Escherichia coli was the most frequent species (n = 28, 34.1%), followed by Klebsiella pneumoniae (n = 20, 24.4%). Cox multivariate analysis showed that independent risk factors for ESBL-PE acquisition were low birth weight (adjusted Hazard-ratio (aHR) = 2.7, 95% CI [1.2; 5.9]), cesarean-section, (aHR = 3.4, 95% CI [1.7; 7.1]) and maternal use of antibiotics at delivery (aHR = 2.2, 95% CI [1.1; 4.5]). Our results confirm that mothers play a significant role in the neonatal acquisition of ESBL-PE. In LMICs, public health interventions during pregnancy should be reinforced to avoid unnecessary caesarean section, unnecessary antibiotic use at delivery and low birth weight newborns.

Review of Antibiotic Resistance in the Indian Ocean Commission: A Human and Animal Health Issue

Antimicrobial resistance (AMR) is a major threat to human, animal health, and environment worldwide. For human, transmission occurred through a variety of routes both in health-care settings and community. In animals, AMR was reported in livestock, pets, and wildlife; transmission of AMR can be zoonotic with the probably most important route being foodborne transmission. The Indian Ocean Commission (IOC), composed of Comoros, Madagascar, Mauritius, Reunion (France), and Seychelles recognized the surveillance of AMR in both animal and human as a main public health priority for the region. Mayotte, French overseas territory, located in Comoros archipelago, was also included in this review. This review summarized our best epidemiological knowledge regarding AMR in Indian Ocean. We documented the prevalence, and phenotypic and genotypic profiles of prone to resistance Gram-positive and Gram-negative bacteria both in animals and humans. Our review clearly pointed out extended-spectrum β-lactamase and carbapenemase-producing Enterobacteriaceae as main human and animal health issue in IOC. However, publications on AMR are scarce, particularly in Comoros, Mayotte, and Seychelles. Thus, research and surveillance priorities were recommended (i) estimating the volume of antimicrobial drugs used in livestock and human medicine in the different territories [mainly third generation cephalosporin (3GC)]; (ii) developing a “One Health” surveillance approach with epidemiological indicators as zoonotic foodborne pathogen (i.e., couple Escherichia coli resistance to 3GC/carbapenems); (iii) screening travelers with a history of hospitalization and consumption of antibiotic drug returning from at risk areas (e.g., mcr-1 transmission with China or hajj pilgrims) allowing an early warning detection of the emergence for quick control measures implementation in IOC.

Detection of Escherichia coli ST131 clonal complex (ST705) and Klebsiella pneumoniae ST15 among faecal carriage of extended-spectrum β-lactamase- and carbapenemase-producing Enterobacteriaceae

PURPOSE

The objective of the present study was to evaluate the prevalence of intestinal colonization with extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae (ESBL-E) and carbapenemase-producing Enterobacteriaceae (CPE) in non-selected hospitalized and non-hospitalized patients from the same geographic area of Madrid.

METHODOLOGY

A total of 501 fecal samples were screened. Diluted samples in saline were cultured in MacConkey agar plates with ceftazidime, cefotaxime, imipenem and meropenem disks. Colonies growing within the inhibition zone of either disk were selected. Characterization of ESBLs and CPEs were performed by PCR and sequencing. The Wider system was used for the bacterial identification. In addition, clonal analysis was carried out for species predominant among the fecal carriage.

KEY FINDINGS

Among the 501 patients enrolled, 43 (8.6 %) carried ESBL-E and 8 (1.6 %) patients exhibited CPE. The main intestinal colonizer among ESBL-E was CTX-M-producing Escherichia coli isolates in both settings (community and hospital). ST131 clonal complex was the most common among faecal ESBL-producing E. coli. All gut carriers of CPE were hospitalized patients, Klebsiella pneumoniae being the most prevalent species. Two OXA-48-producing K. pneumoniae isolates belonging to ST15 were detected.

CONCLUSION

Present study reveals that faecal carriage of ESBL is common among inpatients and outpatients, whereas carbapenemase producers are only present in the hospital setting. Therefore, active surveillance will be useful for reducing transmission of antimicrobial-resistant bacteria and preventing infection.

Resistance to antimicrobial drugs in different surface waters and wastewaters of Guadeloupe

OBJECTIVE

The first aim of this study was to evaluate the antimicrobial resistance of Enterobacteriaceae in different water environments of Guadeloupe and especially those impacted by waste water treatment plants (WWTP) effluents. The second objective was to characterize the genetic basis for antibiotic resistance of extended-spectrum beta-lactamase (ESBL) and AmpC beta-lactamase producing Enterobacteriaceae isolates (ESBLE and AmpCE).

METHODS

We have collected 70 surface waters (river and sea samples) impacted or not by WWTP and 18 waste waters from 2 WWTPs in 2012 and 2013. We i) determined the total and resistant bacterial counts and ii) tested isolated Enterobacteriaceae for their antimicrobial susceptibility. We also studied the genetic basis for antibiotic resistance of ESBLE and AmpCE, and the genetic background of Escherichia coli.

RESULTS

In rivers, contamination with Escherichia coli and antibiotic resistant coliforms (ARC) increased from the source to the mouth. Highest levels of river contamination with E. coli (9.26 x 105 MPN/100mL) and ARC (2.26 x 108 CFU/mL) were observed in surface water sampled near the discharge. A total of 246 Enterobacteriaceae strains resistant to antibiotics were isolated, mostly from waste waters and from river water collected near the discharge. Among these strains, 33 were Extended Spectrum Beta Lactamase (ESBLE) and 8 E. coli were AmpC beta-lactamase producers. All the ESBLE were isolated from waste waters or from river water collected near the discharge. The blaCTX-M gene was present in 29 of the 33 ESBLE strains, with 24 belonging to group 1. Numerous strains (68.7%) showed more than one acquired antibiotic resistance mechanism. E. coli strains belonged to different phylogenetic groups; among the B2 group, most strains belonged to the ST131 clone.

CONCLUSION

Our results demonstrated that many human activities can supply antibiotic-resistant bacteria in surface water. Nevertheless, WWTPs were the most important supplier of ESBLE in water environment of Guadeloupe.

Fecal carriage of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella spp. in a Turkish community

BACKGROUND/AIM

The aim of this study was to determine the prevalence of fecal carriage of extended-spectrum beta-lactamase (ESBL)-producing bacteria, enzyme types, and risk factors affecting colonization.

MATERIALS AND METHODS

A total of 576 stool samples from outpatients were examined between October 2012 and May 2013. Screening was done with selective EMB plates. ESBL were detected by double-disk synergy and confirmed agar strip gradient methods. Enzyme types were determined by PCR.

RESULTS

The prevalence of fecal carriage was found as 30% (173 of 576). Recent use of antibiotics, hospitalization and surgical operation, diabetes, crowded household populations, and old age were associated with higher carriage rates. Of the ESBL-producing bacteria, 87.5% were positive for bla_CTX-M genes. Of the bla_CTX-M gene-positive isolates, 95.2% were positive for bla_CTX-M-1 genes; among these, 82.2% were positive for bla_CTX-M-3 and 67.7% were positive for bla_CTX-M-15 genes while 62.5% isolates were positive for both bla_CTX-M-3 and bla_CTX-M-15 genes Conclusions: A high rate (30%) of fecal carriage of ESBL bacteria was found in an adult population. The predominant beta-lactamase enzyme types were CTX-M-3 and CTX-M-15.

Intense pre-admission carriage and further acquisition of ESBL-producing Enterobacteriaceae among patients and their caregivers in a tertiary hospital in Rwanda

OBJECTIVES

To assess the presence and risk factors of intestinal carriage of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) among patients admitted to the University Teaching Hospital of Butare and among their attending caregivers, and to analyse the acquisition of ESBL-PE carriage during hospital stay and associated factors.

METHODS

We screened 392 patients and their attending caregivers at admission and discharge for ESBL-PE carriage. Bacterial species were determined using the API-20E system, and antimicrobial susceptibility testing was performed by agar disc diffusion. Data on socio-economic status, diet, behaviour, household assets, livestock and hospital procedures were collected.

RESULTS

At admission, 50% of the patients showed intestinal ESBL-PE carriage (Escherichia coli, 51%; Klebsiella pneumoniae, 39%; Enterobacter cloacae, 19%) as did 37% of their caregivers. Co-resistance was common but no carbapenem resistance was detected. At discharge, the proportion of ESBL-PE-colonised patients increased to 65% (caregivers, 47%) with almost complete carriage in paediatric patients (93%). The acquisition rate among initially non-colonised patients was 55% (or, 71/1000 patient days). Independent predictors of admission carriage included a colonised caregiver, prior antibiotic intake, egg consumption and neglecting to boil drinking water, whereas being a paediatric patient, undergoing surgery and male gender predicted acquisition during hospitalisation.

CONCLUSIONS

Abundant admission carriage of ESBL-PE and a high acquisition rate in a Rwandan university hospital point to potential intrahospital transmission and community dissemination. Caregivers are an additional source of possible spread. Risk factors of colonisation such as diet and water source need to be tackled to prevent the further emergence and spread of ESBL-PE.

Faecal carriage rate of extended-spectrum β-lactamase-producing Enterobacteriaceae in hospitalised patients and healthy asymptomatic individuals coming for health check-up

The prevalence of extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE) in hospitalised and community patients is of significant public health concern. The aim of this study was to estimate the faecal carriage rate of ESBL-PE in hospitalised patients and healthy asymptomatic individuals coming for health check-up. Non-repetitive, consecutive stool samples from 480 adults (260 healthy individuals and 220 hospitalised patients) aged ≥18 years from November 2011 to July 2013 were screened using MacConkey agar supplemented with ceftazidime. All screen-positive isolates were identified to species level and were tested for ESBL production. Representative ESBL-PE isolates were subjected to susceptibility testing and multiplex ESBL PCR. The faecal carriage rate of ESBL-PE was found to be 62.7% among hospitalised patients and 33.8% among healthy asymptomatic individuals. The most common ESBL-PE was Escherichia coli (70.3% and 78.4% in hospitalised patients and healthy individuals, respectively), followed by Klebsiella pneumoniae (26.8% and 17.0%). ESBL-PE showed the highest sensitivity to carbapenems (85% and 100%, respectively), followed by amikacin (67.2% and 98%), cefoperazone/sulbactam (27.8% and 88.2%) and piperacillin/tazobactam (18% and 74.5%). Ciprofloxacin exhibited a high level of resistance among both groups. Molecular analysis for ESBL genes showed a predominance of the CTX-M gene. In conclusion, the faecal carriage rate of ESBL-PE among hospitalised patients was almost double that of healthy individuals. Carriage of carbapenem-resistant isolates is emerging among hospitalised patients. The spread of these organisms in the community merits radical measures to improve sanitation and implement antibiotic stewardship.

High rate of faecal carriage of extended-spectrum β-lactamase-producing Enterobacteriaceae in healthy children in Bangui, Central African Republic

The aim of this study was to estimate the prevalence of extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) in faeces of healthy children aged 0-59 months in Bangui (Central African Republic). Stool samples of 134 children, recruited for a matched case-control study, were cultured on a commercial ESBL-selective chromogenic medium (CHROMagar ESBL, France). The phenotypic resistance patterns of isolated strains were investigated, as well as the genetic basis for antibiotic resistance. The factors associated with increased risk for ESBL-E carriage were also studied. The prevalence of ESBL-E carriage was 59% (79/134), one of the highest reported worldwide. The only factor found to be associated with carriage was living in a highest-income family (p=0.03). In all, 83 ESBL-E were recovered as simultaneous carriage of two strains was detected in four children. bla_CTX-M-15 was found in all strains except two, frequently associated with qnr (54/81, 66%) and aac(6')-Ib-cr (35/81, 43%) genes. Escherichia coli, the most commonly recovered species (51/83, 61%), was assigned mainly to the pandemic B2-O25b-ST131 group (39/51, 76%). Resistance transfer, which was studied in 20 randomly selected ESBL-E strains, was successful in 13 (13/20, 65%) isolates. In eight of these isolates (8/13, 62%), bla_CTX-M-15 genes were found in incompatibility group FIb conjugative plasmids. We found one of the highest prevalence rates of faecal carriage of ESBL-E reported worldwide, highlighting the need to improve control of the distribution of antibiotics in limited-resource countries.

Neonatal infections with multidrug-resistant ESBL-producing E. cloacae and K. pneumoniae in Neonatal Units of two different Hospitals in Antananarivo, Madagascar

Background

We investigated the molecular mechanism of ß-lactam resistance in extended-spectrum ß-lactamase (ESBL)-producing Enterobacterial strains isolated in neonatal units of different hospitals in Anatnanarivo, Madagascar.

Methods

Bacteria were identified by standard biochemical methods, disc diffusion antibiograms and Etest. Resistance genes were sought by PCR. Strains were characterized by Rep-PCR (Diversilab), plasmid analysis and rep-typing.

Results

From April 2012 to March 2013, 29 ESBL-producing E. cloacae and 15 K. pneumoniae were isolated from blood culture (n = 32) or gastric samples (n = 12) performed at day 0 or 2 from 39/303 newborns suspected of early neonatal infection. These infants were treated with expanded spectrum cephalosporins, due to lack of carbapenems, leading to a high mortality rate (45 %). Isolates recovered were all, but 4, multidrug resistant, particularly to fluoroquinolones (FQ) except for 21 E. cloacae isolates. Isolates produced TEM-1 and CTX-M-15 ß-lactamases and their genes were located on several self-transferable plasmids of variable sizes sizes that could not be linked to a major plasmid incompatibility group. E. cloacae isolates belonged to 6 Rep-types among which two counted for 11 isolates each. The FQ resistant E. cloacae isolates belonged to one clone, whereas the FQ susceptible E. cloacae isolates belonged to four clones. The K. pneumoniae isolates belonged to 9 Rep-types among which one included five isolates.

Conclusion

This study is the first molecular characterization of ESBL-producing isolates from neonatology units in Madagascar, a country with limited epidemiological data. It revealed an important multi-clonal dissemination of CTX-M-15-producing isolates reflecting both the high community carriage and the very early nosocomial contamination of the neonates.

Extended-spectrum beta-lactamase--producing enterobacteriaceae in the intensive care unit: acquisition does not mean cross-transmission

Background

In intensive care unit (ICU), infection and colonization by resistant Gram-negative bacteria increase costs, length of stay and mortality. Extended-spectrum beta-lactamase − producing Enterobacteriaceae (ESBL-E) is a group of pathogens increasingly encountered in ICU setting. Conditions that promote ESBL-E acquisition are not completely understood. The increasing incidence of infections related to ESBL-E and the unsolved issues related to ESBL-E cross-transmission, prompted us to assess the rates of referred and acquired cases of ESBL-E in ICU and to assess patient-to-patient cross-transmission of ESBL-E using a multimodal microbiological analysis.

Methods

During a 5-month period, all patients admitted to a medical ICU were tested for ESBL-E carriage. A rectal swab was performed at admission and then twice a week until discharge or death. ESBL-E strains were analyzed according to antibiotic susceptibility pattern, rep-PCR (repetitive-element Polymerase chain reaction) chromosomal analysis, and plasmid PCR (Polymerase chain reaction) analysis of ESBL genes. Patient-to-patient transmission was deemed likely when 2 identical strains were found in 2 patients hospitalized simultaneously in the ICU.

Results

Among the 309 patients assessed for ESBL-E carriage on admission, 25 were found to carry ESBL-E (importation rate: 8 %). During follow-up, acquisition was observed among 19 of them (acquisition rate: 6.5 %). Using the multimodal microbiological approach, we found only one case of likely patient-to-patient ESBL-E transmission.

Conclusions

In unselected ICU patients, we found rather low rates of ESBL-E referred and acquired cases. Only 5 % of acquisitions appeared to be related to patient-to-patient transmission. These data highlight the importance of jointly analyzing phenotypic profile and molecular data to discriminate strains of ESBL-E.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1489-z) contains supplementary material, which is available to authorized users.

Community-Onset Extended-Spectrum β-Lactamase-Producing Enterobacteriaceae Invasive Infections in Children in a University Hospital in France

Limited data is available on pediatric community-onset infections with extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE), but such infections may affect both the efficacy of empiric antibiotic therapy and the rational use of antibiotics.We retrospectively analyzed data from 2007 to 2012 for all children ≤16 years old with a positive ESBL-PE strain from usually sterile sites within 48 hours of admission in a tertiary hospital in France. We analyzed healthcare- and community-associated infections among community-onset infections. In total, 3612 Enterobacteriaceae isolates were collected; the prevalence of ESBL-PE infection increased over the study period, from 2.4% to 5.1% (P < 0.001). Among the 90 children with a first community-onset ESBL-PE infection, 58% (n = 52) had a healthcare-associated infection, and 87% of isolates were susceptible to amikacin. As compared with patients with community-associated infections, those with healthcare-associated infections had fewer urinary tract infections (UTIs) (86% vs 97%) and Escherichia coli infections (35% vs 84%) and more Klebsiella pneumoniae infections (46% vs 8%). Inappropriate empiric treatment was prescribed for 54 patients (64%), but a favorable outcome was observed in 46 of 49 (94%) and 1 of 5 (20%) patients with UTIs and non-UTIs, respectively (P < 0.001). Among patients with community-associated infections, 85% had at least 1 risk factor for ESBL-PE infections. In conclusion, the prevalence of community-onset ESBL-PE infections doubled during the study period. These infections mainly occurred among children with healthcare-associated criteria or identified risk factors. Amikacin is an alternative to carbapenems for empiric treatment because most of these infections involved urinary tract and susceptible isolates.

Social structure and Escherichia coli sharing in a group-living wild primate, Verreaux's sifaka

Background

Epidemiological models often use information on host social contacts to predict the potential impact of infectious diseases on host populations and the efficiency of control measures. It can be difficult, however, to determine whether social contacts are actually meaningful predictors of transmission. We investigated the role of host social structure in the transmission of Escherichia coli in a wild population of primates, Verreaux’s sifakas (Propithecus verreauxi). Using multilocus sequence typing (MLST), we compared genetic similarities between E. coli isolates from different individuals and groups to infer transmission pathways.

Results

Correlation of social and transmission networks revealed that membership to the same group significantly predicted sharing of E. coli MLST sequence types (ST). Intergroup encounter rate and a measure of space-use sharing provided equally potent explanations for type sharing between social groups when closely related STs were taken into account, whereas animal age, sex and dispersal history had no influence. No antibiotic resistance was found, suggesting low rates of E. coli spillover from humans into this arboreal species.

Conclusions

We show that patterns of E. coli transmission reflect the social structure of this group-living lemur species. We discuss our results in the light of the species’ ecology and propose scent-marking, a type of social contact not considered in previous epidemiological studies, as a likely route of transmission between groups. However, further studies are needed to explicitly test this hypothesis and to further elucidate the relative roles of direct contact and environmental transmission in pathogen transfer.

Electronic supplementary material

The online version of this article (doi:10.1186/s12898-016-0059-y) contains supplementary material, which is available to authorized users.

Colonization of extended-spectrum-β-lactamase- and NDM-1-producing Enterobacteriaceae among pregnant women in the community in a low-income country: a potential reservoir for transmission of multiresistant Enterobacteriaceae to neonates

The spread of extended-spectrum-β-lactamase-producing Enterobacteriaceae (ESBL-PE) in low-income countries, where the burden of neonatal sepsis is high, may have a serious impact on neonatal mortality rates. Given the potential for mother-to-child transmission of multiresistant bacteria, this study investigated the ESBL-PE rectal colonization among pregnant women at delivery in the community in Madagascar and estimated a prevalence of 18.5% (95% confidence interval, 14.5% to 22.6%). One strain of Klebsiella pneumoniae isolated was also a New Delhi metallo-β-lactamase-1 (NDM-1) producer.

High prevalence and risk factors of fecal carriage of CTX-M type extended-spectrum beta-lactamase-producing Enterobacteriaceae from healthy rural residents of Taian, China

The study was carried out to understand the prevalence of CTX-M type extended-spectrum beta-lactamase (ESBL)-harboring Enterobacteriaceae and to analyze risk factors related with fecal carriage in healthy rural residents in Taian, China. A total of 620 stool samples were collected from rural residents. The ESBL-positive Enterobacteriaceae was screened using ChromID ESBL agar, and then further confirmed by double-disk diffusion. The CTX-M genes were determined using polymerase chain reaction. The risk factors associated with fecal carriage of CTX-M-positive isolates were analyzed using the standard statistic methods. 458 isolates carrying CTX-M gene (458/620, 73.9%) were obtained from different individuals, and the most dominant genotype was CTX-M-9 group (303/458, 66.2%). The dominant species were Escherichia coli (E. coli; 403/458, 88.0%) and Klebsiella pneumoniae (K. pneumoniae; 26/458, 5.7%) among the isolates carrying CTX-M genes. All the CTX-M producers were resistant to ampicillin, cefazolin, cefuroxime, and ceftriaxone, but were all susceptible to biapenem, imipenem, and meropenem. The results of multivariate logistic regression model identified the enrollment in formal education (OR 2.321; 95% CI 1.302–3.768; P= 0.039), the hospitalization history within the last 6 months (OR 1.753; 95% CI 1.127–2.584; P= 0.031) and the antibiotics use within the last 6 months (OR 1.892; 95% CI 1.242–2.903; P= 0.034). The three variables were significantly associated with carriage of CTX-M ESBL producers (x² = 21.21; df = 3; P< 0.001). The prevalence of fecal carriage of CTX-M ESBL-producing Enterobacteriaceae among healthy rural humans in Taian was high, and the recent antibiotic use and hospitalization history may be the important contributors.

Identification of nasal colonization with β-lactamase-producing Enterobacteriaceae in patients, health care workers and students in Madagascar

This study assesses the nasal occurrence of β-lactamase-producing Enterobacteriaceae both in patients in a hospital department of infectious diseases at admission and in healthy Madagascan students and health care workers. Nasal swabs from 681 students, 824 health care workers, and 169 patients were obtained in Antananarivo, Madagascar, and transferred to Germany. Screening for β-lactamase (ESBL, ampC) producing Enterobacteriaceae was performed by cultural and molecular approaches, comprising Brilliance ESBL agar, E-testing, ABCD-testing, and commercial hyplex ESBL and SuperBug ID PCR. Regarding ESBL-positive strains and strains with resistance against at least three out of the four tested bactericidal antibiotic drugs, 0.3% (five out of 1541) of the students and health care workers group showed nasal colonization, whereas colonization was observed in 7.1% (12 out of 169) of the hospitalized patients at admission. No appreciably reduced detection rates after sample storage and intercontinental transport were observed. A considerable proportion of nasal colonization with cephalosporin-resistant Enterobacteriaceae was demonstrated in Madagascan hospital patients at admission, posing a risk of developing future endogenous infections. The nasal colonization of healthy individuals was negligible. Good storage and transport stability of Enterobacteriaceae will allow for future studies even in areas difficult to access.

Extended spectrum beta-lactamase carriage state among elderly nursing home residents in Beirut

Introduction. ESBL-producing Enterobacteriaceae can cause severe infections, but they are also isolated from the stool of asymptomatic subjects. Faecal carriage of such organism is poorly understood. Methods. First phase of the study was cross-sectional with prevalence and epidemiology of ESBL faecal carriage in two nursing homes in Beirut: 57 residents in the first (NH1) and 151 residents in the second (NH2). In second phase, faecal swabs from cohort of NH1 residents were examined for carriage at six-week intervals over three-month period. Residents' charts were reviewed to assess carriage risk factors. Results. Over 3 consecutive samplings at NH1, 81% of residents were at least one-time carriers with 50% at the first round, 60.4% at the second, and 74.5% at the last one. At NH2, 68.2% of residents were carriers. Constipation (in NH1) and antibiotic intake (in NH2) were significantly associated with higher ESBL faecal carriage while the length of stay at the nursing home (in NH2) was associated with less carriage. Conclusion. Faecal carriage of ESBL-producing Enterobacteriaceae is high among nursing home patients in Beirut. The rate of carriage changes rapidly and significantly over time either with multiple factors playing a possible role like outbreak spreading, antibiotic, and health care system exposure.

Anti-ESBL activity of silver nanoparticles biosynthesized using soil Streptomyces species

Emergence of antibiotic resistance by bacteria has become a serious threat for public health worldwide. In this study, Streptomyces isolated from fertile soil sample was tested for biosynthesis of silver nanoparticles (AgNps) using cell-free supernatant and synthesized AgNps were screened for anti-ESBL (extended spectrum b-lactamase) activity against multi-drug resistant (MDR) ESBL-producing strain Klebsiella pneumoniae (ATCC 700603) and other medically important pathogens. Synthesis of AgNps was confirmed by change in pale yellow color to dark brown color and characteristic absorption spectra at 420 nm. The XRD spectrum displayed typical peaks of crystalline silver and EDAX analysis showed a major signal for silver. FTIR spectra revealed prominent peaks at 3,294 cm-1 (NH stretching due to amide group), 2,952 cm-1 (aldehydic C–H stretching) 1,658 cm-1 indicating the presence of carbonyl group. AgNps were spherical in shape with size ranging from 20 to 70 nm. The synthesized AgNps showed significant antimicrobial activity against standard ESBL pathogen K. pneumoniae (22 mm), 21 mm against clinical ESBL isolate E. coli and 16 mm against clinical ESBL isolates K. pneumoniae and Citrobacter species, respectively. The results of this study suggest that AgNps synthesized by Streptomyces sp. VITSJK10 can be used as a potential alternative to control MDR ESBL pathogens. The present study aimed for green synthesis of AgNps using Streptomyces species and to explore its anti-ESBL activity.

Fecal carriage of extended-spectrum β-lactamase-producing Enterobacteriaceae in community setting in Casablanca

BACKGROUND

The importance of community-acquired infections due to extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE) has been increasingly recognized in recent years. This study aimed to determine the prevalence of intestinal carriage of ESBL-PE in the community in Casablanca, Morocco.

METHODS

During 6 months (2013), 93 fecal samples were examined for ESBL-PE. Isolates expressing an ESBL phenotype were investigated for the presence of genes encoding β-lactamases and plasmid-mediated quinolone resistance. Conjugation experiments were done to determine the mobility of ESBL genes.

RESULTS

The prevalence of fecal carriage of ESBL-PE was 4.3% (4/93; 95% CI, 0.2-8.4). Klebsiella pneumoniae (n = 2), Enterobacter cloacae (n = 2), Escherichia coli (n = 1), and Serratia odorifera (n = 1) were the ESBL-producing species. Four (66.7%) of these isolates were multidrug-resistant. The blaSHV-12 (n = 5) was the most frequent ESBL gene detected, followed by blaCTX-M-15 (n = 3).The non-ESBL gene detected was blaTEM-1 (n = 5). One isolate harbored the qnrB1 variant. RESULTS of conjugation experiments indicated that blaSHV-12 + blaTEM-1 + qnrB1 and blaCTX-M-15 + blaTEM-1 genes were co-transferred and that these genes were carried by a conjugative plasmid of high molecular weight (125 kb).

CONCLUSION

Our results show the importance of the intestinal tract as a reservoir for ESBL-PE in the community in Morocco.

Emerging rapid resistance testing methods for clinical microbiology laboratories and their potential impact on patient management

Atypical and multidrug resistance, especially ESBL and carbapenemase expressing Enterobacteriaceae, is globally spreading. Therefore, it becomes increasingly difficult to achieve therapeutic success by calculated antibiotic therapy. Consequently, rapid antibiotic resistance testing is essential. Various molecular and mass spectrometry-based approaches have been introduced in diagnostic microbiology to speed up the providing of reliable resistance data. PCR- and sequencing-based approaches are the most expensive but the most frequently applied modes of testing, suitable for the detection of resistance genes even from primary material. Next generation sequencing, based either on assessment of allelic single nucleotide polymorphisms or on the detection of nonubiquitous resistance mechanisms might allow for sequence-based bacterial resistance testing comparable to viral resistance testing on the long term. Fluorescence in situ hybridization (FISH), based on specific binding of fluorescence-labeled oligonucleotide probes, provides a less expensive molecular bridging technique. It is particularly useful for detection of resistance mechanisms based on mutations in ribosomal RNA. Approaches based on MALDI-TOF-MS, alone or in combination with molecular techniques, like PCR/electrospray ionization MS or minisequencing provide the fastest resistance results from pure colonies or even primary samples with a growing number of protocols. This review details the various approaches of rapid resistance testing, their pros and cons, and their potential use for the diagnostic laboratory.

Antibiotic resistance and extended spectrum beta-lactamases: Types, epidemiology and treatment

Antibiotic resistance is a problem of deep scientific concern both in hospital and community settings. Rapid detection in clinical laboratories is essential for the judicious recognition of antimicrobial resistant organisms. Production of extended-spectrum β-lactamases (ESBLs) is a significant resistance-mechanism that impedes the antimicrobial treatment of infections caused by Enterobacteriaceae and is a serious threat to the currently available antibiotic armory. ESBLs are classified into several groups according to their amino acid sequence homology. Proper infection control practices and barriers are essential to prevent spread and outbreaks of ESBL producing bacteria. As bacteria have developed different strategies to counter the effects of antibiotics, the identification of the resistance mechanism may help in the discovery and design of new antimicrobial agents. The carbapenems are widely regarded as the drugs of choice for the treatment of severe infections caused by ESBL-producing Enterobacteriaceae, although comparative clinical trials are scarce. Hence, more expeditious diagnostic testing of ESBL-producing bacteria and the feasible modification of guidelines for community-onset bacteremia associated with different infections are prescribed.

Evaluation of existence and transmission of extended spectrum beta lactamase producing bacteria from post-delivery women to neonates at Bugando Medical Center, Mwanza-Tanzania

BACKGROUND

Extended spectrum beta-lactamase producing bacteria (ESBL) are common causes of neonatal sepsis worldwide. Neonatal sepsis due to ESBL is associated with increased morbidity and mortality at Bugando Medical Centre (BMC). Due to limited information on the sources of these ESBL strains at BMC, this study was conducted to evaluate the existence, magnitude and transmission of ESBL from post-delivery women to neonates at BMC, Mwanza-Tanzania.

RESULTS

A cross-sectional study was conducted at obstetrics and neonatal wards from May to July 2013, involving post-delivery women and their neonates. Rectal swabs were collected and processed to identify the ESBL strains and their antimicrobial susceptibility patterns. Patients' data were obtained using a standardized data collection tool. We enrolled 113 women and 126 neonates with mean age of 26.5 ± 5.5 years and median gestation age [IQR] of 39 [35-40] weeks respectively. The prevalence of ESBL carriage among women and neonates were 15% (17/113) and 25.4% (32/126) respectively. The acquisition of ESBL isolates among neonates on day 1, day 3 and day 7 were 60.0% (21/35), 25.7% (9/35) and 14.3% (5/35) respectively. There was no phenotypic similarity between ESBL strains from women and their respective neonates, suggesting other sources of transmission. Neonates given antibiotics were more likely to carry ESBL than those not given [100% (32/32) versus 86% (81/94), p = 0.018].

CONCLUSION

The carriage rate of ESBL strains among post-delivery women and neonates at BMC is high. Our findings suggest that neonates acquire these strains from sources other than post-delivery women and more than half acquire them on the first day of life. More studies are recommended to further explore the sources of ESBL strains among neonates.

Trends in human fecal carriage of extended-spectrum β-lactamases in the community: toward the globalization of CTX-M

In the last 10 years, extended-spectrum β-lactamase-producing enterobacteria (ESBL-E) have become one of the main challenges for antibiotic treatment of enterobacterial infections, largely because of the current CTX-M enzyme pandemic. However, most studies have focused on hospitalized patients, though today it appears that the community is strongly affected as well. We therefore decided to devote our investigation to trends in ESBL-E fecal carriage rates and comprehensively reviewed data from studies conducted on healthy populations in various parts of the world. We show that (i) community ESBL-E fecal carriage, which was unknown before the turn of the millennium, has since increased significantly everywhere, with developing countries being the most affected; (ii) intercontinental travel may have emphasized and globalized the issue; and (iii) CTX-M enzymes, especially CTX-M-15, are the dominant type of ESBL. Altogether, these results suggest that CTX-M carriage is evolving toward a global pandemic but is still insufficiently described. Only a better knowledge of its dynamics and biology will lead to further development of appropriate control measures.