Antibacterial agents and the fight against antibiotic resistance: A real-world evidence analysis of consumption and spending by an Italian healthcare company.

INTRODUCTION: The escalating bacterial resistance stands as an increasingly pertinent concern, particularly in the post-pandemic era where the use of antibiotics appears to be relentlessly surging, giving rise to profound apprehensions. The substantial utilization of last-generation penicillins and cephalosporins is anticipated to imminently result in the emergence of superbugs for which therapeutic solutions will be scarce. METHODS: An analysis of antibiotic consumption in the hospital setting has been conducted in an Italian healthcare organization. Querying the internal management system facilitated the calculation of indicators and assessment of prescription trends. RESULTS: A comparison has been made between the first half of 2023 and the first half of 2022, to highlight the exponential growth in the consumption of beta-lactam antibiotics, with consumption doubling compared to the previous year's semester. Overall, considering the prescription averages, there is a prescribing growth of +29% concerning hospitalization and +28% concerning hospital discharge. However, it should be noted that the consumption of certain antibiotics such as sulphonamides and trimethoprim (-103.00%), tetracyclines (-54.00%), macrolides, lincosamides and streptogramins (-50.00%) and colistin (-13.00%) decreased. CONCLUSION: This real-world evidence analysis aimed to support the justified and comprehensible global concerns regarding bacterial resistance. The extensive consumption of antibiotics will inevitably lead to the development of increasingly drug-resistant bacteria for which no antibiotic may be efficacious. National programs addressing antibiotic resistance and the awareness of all healthcare personnel must be accorded the utmost priority to enhance consumption data and, consequently, safeguard future human survival.

Necrotizing fasciitis: A highly fatal infection.

BACKGROUNDS: Necrotizing fasciitis is a severe bacterial infection characterized by involvement of all skin's layers, including the superficial fascia. Diagnosis and treatment must be as quick as possible. Once suspected, extensive surgical debridement is required. METHODS: All necrotizing fasciitis, managed in our hospital in Dijon, during the period from January 2011 to May 2021, were retrospectively analyzed. Demographics characteristics of patients, biological parameters, and type of bacteria were collected. Statistical analysis was performed on the cost of hospitalization, as well as on the death rate between type I and II NF and the speed of management. Student's t-test and Chi2 test were performed with a significant level P<0.05. FINDINGS: A total of 65 patients were included over the period. The mean age was 68.8 years. The average length of stay was 32.4 days, with an average cost of 79,305 €. The main locations were the lower limbs (57%) and the perineum (35%). Cost of hospitalization did not differ between type I and II (P=0.21), unlike mortality rate (P=0.003). Furthermore, the mortality rate according to the speed of management did not vary in our series (P=0.45). CONCLUSION: Necrotizing fasciitis is quickly fatal if left untreated. Early diagnosis, combined with surgical debridement and probabilistic antibiotic therapy are required. Our study shows the impact of necrotizing fasciitis in terms of cost to society and the importance of prevention of certain risk factors. A global management of the patient is necessary to increase the survival rate.

SARS-CoV-2 caused a surge in antibiotic consumption causing a silent pandemic inside the pandemic. A retrospective analysis of Italian data in the first half of 2022.

BACKGROUND: The phenomenon of antibiotic resistance shows no sign of stopping, despite global policies to combat it that have been in place for several years. The risk of forms of pathogenic microorganisms that are increasingly resistant to common antibiotics has led health authorities around the world to pay greater attention to the phenomenon. The worrying situation, has led to further recommendations from the World Health Organization (WHO) and national recommendations in Italy through the new National Plan against Antibiotic Resistance 2022-2025 (PNCAR 2022-2025). AIM: This manuscript aims to raise the awareness of all health professionals to follow what is suggested by regulatory agencies and scientific societies. METHOD: We conducted a retrospective study of antibiotic pharmacoutilization in Italy, in the Campania region at the Azienda Sanitaria Locale (ASL) Napoli 3 Sud, on consumption in the first half of 2022 in a population of more than 1 million people. RESULT: The results indicate that consumption, based on defined daily doses (DDDs), is above the national average. Probably the COVID-19 pandemic has influenced this growth in prescriptions. CONCLUSIONS: Our study suggests an informed and appropriate use of antibiotics, so as to embark on a virtuous path in the fight against antibiotic resistance.

Impact of clinical pharmacist interventions in a bone and joint infection orthoseptic surgery unit.

OBJECTIVES: To assess the impact of interventions of a clinical pharmacist in a unit of orthopedic surgery specialized in bone and joint infections. METHODS: Daily, in routine, a clinical pharmacist analyzed medication prescribed to inpatients via a computerized physician order entry (CPOE) (Phedra software). His attention was particularly focused on the impact of antibiotics on other medications. For this study, all of the pharmacist interventions (PI) have been retrospectively collected, then anonymized, and assessed over a two-month period. RESULTS: Thirty-eight patients were hospitalized during the study period, with a mean age of 63 years old. Forty-five interventions were identified which represents a mean of 1.18 pharmaceutical interventions per patient. Most of them concerned lack of follow-up (24%) and drug-drug interactions (22%) and widely non-anti-infectious medication (35 interventions) with levothyroxine (10 interventions) as the most involved non-anti-infectious molecule. Among antibiotics, with respectively 9 and 8 interventions, rifampicin and fluoroquinolones (6 interventions for moxifloxacin) were the most concerned notably for drug-drug interactions with usual treatment. CONCLUSION: In this observational retrospective study, 1.18 pharmacist interventions (PI) per patient were observed. Most of them are lack of follow-up and drug-drug interactions especially with usual treatment of patients. Moxifloxacin and rifampicin were the most antibiotics involved. Patients' characteristics (older, polypharmacy), long-term hospitalization and surgery are known to be predictive factors of medication errors and this study highlights the importance of the presence of clinical pharmacist in orthopedic surgery wards.

Metallo-beta-lactamase-producing Escherichia coli in the sewage of Mexico City: where do they come from?

While monitoring the presence of antibiotic resistance in municipal wastewater bacteria from Mexico City, five Escherichia coli isolates were found to be resistant to carbapenems, antibiotics of "last resort" used mostly in hospitals. Further analysis revealed that these carbapenem-resistant isolates carried the gene encoding a metallo-beta-lactamase, NDM-5. The gene was found to be beared by a large, ∼145 kb conjugative plasmid, which also carries putative genes encoding resistance to sulfonamides, trimethoprim, tetracycline, ciprofloxacin, and chloramphenicol (although no phenotypic chloramphenicol resistance was detected) and quaternary-ammonium compounds. The plasmid also carried gene mobility determinants, such as integron integrase and two transposases. In addition to the direct public health threat posed by the presence of such multi-resistant organisms in wastewater released into the environment and used for crop irrigation; it is particularly concerning that carbapenem-resistant E. coli is rather rare in Mexican hospitals (<1%), but was found in small, 100 mL samples of municipal wastewater. This suggests that these organisms are under-reported by clinical microbiology laboratories, underlining the usefulness of wastewater monitoring, or that there is an unknown source of such carbapenem-resistant organisms that are being dumped into the wastewater. The source of these bacteria must be assessed and controlled to prevent further spread of this multi-resistance plasmid among other environmental and clinical microorganisms.

[Antibiotic therapy in hospitals: Evaluation of antibiotic prescriptions and determination of factors influencing relevance]. / Antibiothérapie en milieu hospitalier : évaluation des prescriptions d'antibiotiques et détermination des facteurs influençant la pertinence.

OBJECTIVES: To evaluate the relevance and compliance of antibiotic prescriptions made in a Tunisian hospital and study the factors likely to influence them. METHODS: This is a cross-sectional, monocentric study of antibiotic prescriptions belonging to the Watch and Reserve Groups of the World Health Organization's AWaRe classification, between January 1 and February 29, 2020. RESULTS: A total of 310 antibiotic prescriptions were analyzed. Monotherapy represented 89,7 % of prescriptions. The most prescribed molecule was cefotaxime (42,8%). Antibiotic therapy was documented in 13% of cases. The antibiotic prescriptions were rational in 14,5% of cases. One third of prescriptions were irrelevant and 4,8% not justified. The dominant ground for non-compliance was unsuitable duration. The status of the prescriber and the prescribing service were factors influencing the relevance of prescriptions. CONCLUSION: Irrational use of antibiotics was common in this study. As a result, the establishment of an antibiotic therapy guide and a computerized decision-support tool seem essential to guarantee the quality of antibiotic prescriptions.

Effect of sub-inhibitory concentrations of cefepime on biofilm formation by Pseudomonas aeruginosa.

This study investigated the effect of cefepime at sub-minimum inhibitory concentrations (sub-MICs) on in vitro biofilm formation (BF) by clinical isolates of Pseudomonas aeruginosa. The effect of cefepime at sub-MIC levels (½-1/256 MIC) on in vitro BF by six clinical isolates of P. aeruginosa was phenotypically assessed following 24 and 48 h of challenge using the tissue culture plate (TCP) assay. Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to observe the change in expression of three biofilm-related genes, namely, a protease-encoding gene (lasA), fimbrial protein-encoding gene (cupA1), and alginate-encoding gene (algC), in a weak biofilm-producing strain of P. aeruginosa following 24 and 48 h of challenge with sub-MICs of cefepime. The BF morphology in response to cefepime was imaged using scanning electron microscopy (SEM). The TCP assay showed strain-, time-, and concentration-dependent changes in in vitro BF in P. aeruginosa following challenge with sub-MICs of cefepime, with a profound increase in strains with inherently no or weak biofilm-producing ability. RT-PCR revealed time-dependent upregulation in the expression of the investigated genes following challenge with ½ and » MIC levels, as confirmed by SEM. Cefepime at sub-MICs could upregulate the expression of BF-related genes and enhance BF by P. aeruginosa clinical isolates.

Identification of plasmids from Brazilian Chromobacterium violaceum strains.

Chromobacterium violaceum is an opportunistic pathogen found in tropical and subtropical regions worldwide. Chromobacterium violaceum infections are difficult to treat, and many strains are resistant to antibiotics. Recently, a novel plasmid (pChV1) was discovered in the type strain ATCC 12472, suggesting that other C. violaceum strains may harbor extra-chromosomal DNA. The aim of the present study was to detect and compare new plasmids in Brazilian strains of C. violaceum using next-generation sequencing techniques. We obtained draft genomes of six plasmids from strains isolated from the Amazon region and aligned them with pChV1. At least three plasmids, CVAC05, CVACO2, and CVT8, were similar to pChV1. Phylogenetic analysis suggested that these new extra-chromosomal DNA sequences have a common origin with pChV1 but have diverged. Many of the ORFs detected were related to plasmid segregation/maintenance, viral structural proteins, and proteins with unknown functions. These findings may enable better genetic manipulation of C. violaceum, which will enhance our ability to exploit this valuable microorganism in industrial and clinical applications.

The progress of type II persisters of Escherichia coli O157:H7 to a non-culturable state during prolonged exposure to antibiotic stress with revival being aided through acid-shock treatment and provision of methyl pyruvate.

Persisters are a form of dormancy in bacteria that provide temporary resistance to antibiotics. The following reports on the formation of Escherichia coli O157:H7 E318 type II persisters from a protracted (8 days) challenge with ampicillin. Escherichia coli O157:H7 followed a multiphasic die-off pattern with an initial rapid decline (Phase I) of susceptible cells that transitioned to a slower rate representing tolerant cells (Phase II). After 24 h post-antibiotic challenge, the E. coli O157:H7 levels remained relatively constant at 2 log CFU/mL (Phase III), but became non-culturable within 8-days (Phase IV). The revival of persisters in Phase III could be achieved by the removal of antibiotic stress, although those in Phase IV required an extended incubation period or application of acid-shock. The carbon utilization profile of persister cells was less diverse compared with non-persisters, with only methyl pyruvate being utilized from the range tested. Inclusion of methyl pyruvate in tryptic soy agar revived non-cultural persisters, presumably by stimulating metabolism. The results suggest that persisters could be subdivided into culturable or non-culturable cells, with the former representing a transition state to the latter. The study provided insights into how to revive cells from dormancy to aid enumeration and control.

Association between treatment with oral third-generation cephalosporin antibiotics and mortality outcomes in Ebola virus disease: a multinational retrospective cohort study.

OBJECTIVE: To evaluate the association between oral third-generation cephalosporin antibiotic treatment and mortality in Ebola virus disease (EVD). METHODS: This retrospective cohort studied EVD-infected patients admitted to five Ebola Treatment Units in Sierra Leone and Liberia during 2014-15. Empiric treatment with cefixime 400 mg once daily for five days was the clinical protocol; however, due to resource variability, only a subset of patients received treatment. Data on sociodemographics, clinical characteristics, malaria status and Ebola viral loads were collected. The primary outcome was mortality compared between cases treated with cefixime within 48 h of admission to those not treated within 48 h. Propensity scores were derived using clinical covariates. Mortality between treated and untreated cases was compared using propensity-matched conditional logistic regression and bootstrapped log-linear regression analyses to calculate an odds ratio (OR) and relative risk (RR), respectively, with associated 95% confidence intervals (CI). RESULTS: Of 424 cases analysed, 360 (84.9%) met the cefixime treatment definition. The mean age was 30.5 years and 40.3% were male. Median cefixime treatment duration was 4 days (IQR: 3, 5). Among cefixime-treated patients, mortality was 54.7% (95% CI: 49.6-59.8%) vs. 73.4% (95% CI: 61.5-82.7%) in untreated patients. In conditional logistic regression, mortality likelihood was significantly lower among cases receiving cefixime (OR = 0.48, 95% CI: 0.32-0.71; P = 0.01). In the bootstrap analysis, a non-significant risk reduction was found with cefixime treatment (RR = 0.82, 95% CI: 0.64-1.16, P = 0.11). CONCLUSION: Early oral cefixime may be associated with reduced mortality in EVD and warrants further investigation.

OBJECTIF: Evaluer l'association entre le traitement antibiotique oral avec des céphalosporine de troisième génération et la mortalité dans la maladie au virus Ebola (MVE). MÉTHODES: Cette étude de cohorte rétrospective a été menée chez des patients infectés par la maladie au virus Ebola admis dans cinq unités de traitement Ebola en Sierra Leone et au Libéria en 2014-2015. Le traitement empirique avec Cefixime 400 mg une fois par jour pendant cinq jours était le protocole clinique. Cependant, en raison de la variabilité des ressources, seul un sous-ensemble de patients a reçu un traitement. Des données sur la sociodémographie, les caractéristiques cliniques, le statut du paludisme et les charges virales d'Ebola ont été collectées. Le critère principal était la mortalité comparée entre les cas traités au céfixime dans les 48 heures suivant l'admission et ceux non traités dans les 48 heures. Les scores de propension ont été dérivés à l'aide de covariables cliniques. La mortalité entre les cas traités et non traités a été comparée à l'aide d'analyses de régression logistique conditionnelle et de régression log-linéaire bootstrapées pour calculer respectivement un rapport de cotes (OR) et un risque relatif (RR), avec des intervalles de confiance (IC) à 95% associés. RÉSULTATS: Sur 424 cas analysés, 360 (84,9%) répondaient à la définition du traitement au céfixime. L'âge moyen était de 30,5 ans et 40,3% étaient des hommes. La durée médiane du traitement par le céfixime était de 4 jours (IQR: 3, 5). Parmi les patients traités au Cefixime, la mortalité était de 54,7% (IC95%: 49,6 à 59,8%) vs 73,4% (IC95%: 61,5 à 82,7%) chez les patients non traités. Dans la régression logistique conditionnelle, la probabilité de mortalité était significativement plus faible parmi les cas recevant du céfixime (OR = 0,48 ; IC95%: 0,32 à 0,71; P = 0,01). Dans l'analyse bootstrap, une réduction du risque non significative a été trouvée avec le traitement au céfixime (RR = 0,82, IC95%: 0,64 à 1,16 ; P = 0,11). CONCLUSION: Le céfixime par voie orale rapide peut être associé à une mortalité réduite dans la MVE et mérite une investigation plus approfondie.

Critical evaluation of the appetite test for children with severe acute malnutrition.

OBJECTIVES: The appetite test is used to risk stratify for children with severe acute malnutrition (SAM) in inpatient or outpatient care. The test is recommended in guidelines despite lack of evidence. We evaluated its ability to identify children at risk of a poor treatment outcome. METHODS: We conducted an observational study of children diagnosed with SAM at three health facilities in Ethiopia. The appetite test was done independently, and the result did not affect decisions about hospitalisation and clinical care. Data were analysed using mixed linear and logistic regression models. RESULTS: Appetite was tested in 298 (89%) of 334 children enrolled; 56 (19%) passed. Children failing the appetite test had a 6.6% higher weight gain per day (95% CI: 2.6, 10.8) adjusted for type of treatment, oedema, duration of follow-up and age than children passing the test. We found medical complications in 179 (54%) children. Medical complications were associated with blood markers of metabolic disturbance. Children with medical complications tended to have lower weight gain than those without complications (3.5%, 95% CI: -0.25, 7.0). Neither the appetite test nor medical complications were correlated with bacteraemia or treatment failure. CONCLUSIONS: Our findings question the use of the appetite test to identify children who need inpatient care. An assessment of medical complications alone could be a useful risk indicator but needs to be evaluated in other settings.

OBJECTIF: Le test de l'appétit est utilisé pour stratifier les risques chez les enfants souffrant de malnutrition aiguë sévère (MAS) en soins hospitaliers ou ambulatoires. Le test est recommandé dans les directives malgré le manque d'évidence. Nous avons évalué sa capacité à identifier les enfants à risque de mauvais résultats de traitement. MÉTHODES: Nous avons mené une étude observationnelle chez des enfants diagnostiqués avec une MAS dans trois établissements de santé en Ethiopie. Le test de l'appétit a été effectué indépendamment et le résultat n'a pas affecté les décisions d'hospitalisation et de soins cliniques. Les données ont été analysées à l'aide de modèles de régression linéaire et logistique mixtes. RÉSULTATS: : L'appétit a été testé chez 298 (89%) des 334 enfants inscrits; 56 (19%) ont réussi le test. Les enfants qui échouaient au test de l'appétit avaient un gain de poids de 6,6% plus élevé par jour (IC95%: 2,6 à 10,8) ajusté pour le type de traitement, l'œdème, la durée du suivi et l'âge que les enfants réussissant le test. Nous avons trouvé des complications médicales chez 179 (54%) enfants. Des complications médicales ont été associées à des marqueurs sanguins de troubles métaboliques. Les enfants souffrant de complications médicales avaient tendance à avoir un gain de poids plus faible que ceux sans complications (3,5% ; IC95%: -0,25 à 7,0). Ni le test de l'appétit ni les complications médicales ne corrélaient avec une bactériémie ou à un échec du traitement CONCLUSION: Nos résultats remettent en question l'utilisation du test de l'appétit pour identifier les enfants qui ont besoin de soins hospitaliers. Une évaluation des complications médicales à elle seule pourrait être un indicateur de risque utile, mais doit être évaluée dans d'autres contextes MOTS-CLÉS: malnutrition aiguë sévère, appétit, gestionnaire de communauté, évaluation des risques, aliments thérapeutiques.

Groundwater microbial diversity and antibiotic resistance linked to human population density in Yucatan Peninsula, Mexico.

Microbial community composition in selected karst groundwater sites in the Yucatan Peninsula, Mexico, was assessed to determine the environmental variables influencing groundwater microbial diversity. The karst aquifer system is a groundwater-dependent ecosystem and is the world's second largest underwater karst cave system. The area's geology allows precipitation to infiltrate into the groundwater system and prevents accumulation of surface water; as such, groundwater is the only source of fresh water on the peninsula. The sampling locations consisted of three karst sinkholes that extend through the freshwater zone into the saline water, and an abandoned drinking water well of an ocean-side resort, during the dry and rainy seasons. The analysis showed that highly diverse microbial communities are present in the Yucatan groundwater, sustained by permanently warm temperatures and high nutrient input from human activity. Proximity to densely populated areas, such as tourist resorts, is the most important factor influencing both the diversity and presence of fecal bacteria and the antibiotic resistance profile.

Renaissance of vancomycin: approaches for breaking antibiotic resistance in multidrug-resistant bacteria.

The emergence of multidrug-resistant bacteria demands innovations in the development of new antibiotics. For decades, the glycopeptide antibiotic vancomycin has been considered as the "last resort" treatment of severe infections caused by Gram-positive bacteria. Since the discovery of the first vancomycin-resistant enterococci strains in the late 1980s, the number of resistances has been steadily rising, with often life-threatening consequences. As an alternative to the generation of completely new substances, novel approaches focus on structural modifications of established antibiotics such as vancomycin to overcome these resistances. Here, we provide an overview of several promising modifications of vancomycin to restore its efficacy against vancomycin-resistant enterococci.

Impact of liquid hog manure applications on antibiotic resistance genes concentration in soil and drainage water in field crops.

Agricultural practices such as manure applications could contribute to the spread of antibiotic resistance genes (ARGs) within the environment. Our objective was to assess the impact of certain fertilization methods (mineral or manure) and tillage practices (reduced or conventional) on the presence of ARGs and bacteria in soil and drainage water under wheat and grain corn crops. Targeted ARGs tet(T), sul1, and blaCTX-M-1 in liquid hog manure, soil, and water samples were quantified by qPCR. Conventional PCR was used to detect mcr-1 and mcr-2. ARGs in control plots were detected despite the absence of manure, representing an environmental reservoir of resistant microorganisms. The manure application rate higher than 39 m3/ha increased tet(T) and sul1 gene concentrations in soil for more than 180 days. Tillage practices had no impact on ARG concentrations in soil and water samples. The blaCTX-M-1 gene was only detected in seven water samples in 2016, but no link was established with the treatments. The mcr-1 and mcr-2 genes were not detected in all tested samples. This study demonstrated that tet(T) and sul1 gene concentrations increased in soil after liquid hog manure application as well as in drainage water in the next weeks.

Delineating the origins of the multidrug-resistant pathogens in ornamental fish farms by multilocus sequence typing and identification of a novel multidrug-resistant plasmid.

To evaluate the overuse of antibiotics and to identify the origin of pathogens in the ornamental fish industry, we conducted a field investigation of three representative fish farms in Liaoning province, China. Drug-resistant pathogens in the fishponds and groundwater were isolated and subtyped by multilocus sequence typing (MLST). In total, 33 pathogenic strains, including Aeromonas veronii and five other pathogens, were isolated from diseased fish and from groundwater. MLST revealed that A. veronii obtained from diseased fish in three fish farms can be subtyped into four sequence types, which were also identified in the corresponding groundwater. All of the isolates obtained from diseased fish showed resistance to at least four antibiotics. Notably, Citrobacter freundii JY-17 exhibited resistance to the majority of the antibiotics and was a carrier of a megaplasmid with 15 drug resistance genes. PCR assays targeting ß-lactam, kanamycin, macrolide, phenicol, sulfonamide, and trimethoprim resistance genes in the pathogens from the diseased fish and groundwater were also conducted. The results revealed strong correlations between antibiotic treatment and increased antimicrobial resistance in fish pathogens. The results suggested that groundwater is the origin of the pathogens in ornamental fish. Antibiotic treatment of ornamental fish promoted the emergence of resistant pathogens.

Continuing surveillance of invasive Haemophilus influenzae disease in northwestern Ontario emphasizes the importance of serotype a and non-typeable strains as causes of serious disease: a Canadian Immunization Research Network (CIRN) Study.

In the post-Haemophilus influenzae serotype b (Hib) vaccine era, invasive H. influenzae serotype a (Hia) disease emerged in Canadian First Nation, Inuit, and Alaskan Indigenous populations. Previous studies by our group found a high incidence of invasive Hia disease in northwestern Ontario. We retrospectively reviewed 24 cases (4 pediatric and 20 adult) of invasive H. influenzae disease hospitalized at the northwestern Ontario regional hospital between August 2011 and June 2018. The objectives were to further document the changing epidemiology of invasive H. influenzae disease in the region and to discuss potential control measures. Twenty-two H. influenzae isolates were serotyped and characterized using molecular-biological methods. Of the serotyped cases, there were 2 Hib, 9 Hia, and 11 non-typeable (NTHi). All Hia isolates belonged to the most common sequence types (ST) found in Canada (ST-23 and ST-929); 8 out of 9 were pan susceptible to antibiotics. One (11%) of 9 Hia and 5 (45%) of 11 NTHi cases were fatal. Our data on the consistent presence of serious invasive H. influenzae disease, with 41% prevalence of Hia (9 out of 22 serotyped isolates) and 50% prevalence of NTHi strains (11 out of 22), emphasize the importance of continued surveillance of H. influenzae in the post-Hib vaccine era and are critical information to inform potential vaccine development.

Widespread detection of antibiotic-resistant bacteria from natural aquatic environments in southern Ontario.

To elucidate how widespread antibiotic resistance is in the surface water environment, we studied the prevalence of antibiotic resistance bacteria at four locations in southern Ontario. We found that the percentage of bacteria resistant to the antibiotic tetracycline was higher at the river site, which flows through agricultural land, and lower at the lake sites. A total of 225 colonies were selected for further testing of antibiotic disc susceptibility to eight different antibiotics to calculate the multiple antibiotic resistance (MAR) score and the antibiotic resistance index for each site. Although the isolates from the lake site outside the city displayed resistance to fewer antibiotics, their MAR scores were not significantly different from that of the lake sites adjacent to urban beaches, showing that MAR was widespread in the natural water environments tested. Isolation of colonies under selection pressure to tetracycline was found to have a significant effect on the likelihood that the isolates would contain multiple resistance traits for other antibiotics. Identification of isolates selected on tetracycline was compared with that of isolates that were sensitive to tetracycline, and the community composition was found to be distinctly different, although isolates from the genera Chryseobacterium, Pseudomonas, and Stenotrophomonas were found in both communities.

Horizontal transfer of antibiotic resistance genes in clinical environments.

A global medical crisis is unfolding as antibiotics lose effectiveness against a growing number of bacterial pathogens. Horizontal gene transfer (HGT) contributes significantly to the rapid spread of resistance, yet the transmission dynamics of genes that confer antibiotic resistance are poorly understood. Multiple mechanisms of HGT liberate genes from normal vertical inheritance. Conjugation by plasmids, transduction by bacteriophages, and natural transformation by extracellular DNA each allow genetic material to jump between strains and species. Thus, HGT adds an important dimension to infectious disease whereby an antibiotic resistance gene (ARG) can be the agent of an outbreak by transferring resistance to multiple unrelated pathogens. Here, we review the small number of cases where HGT has been detected in clinical environments. We discuss differences and synergies between the spread of plasmid-borne and chromosomal ARGs, with a special consideration of the difficulties of detecting transduction and transformation by routine genetic diagnostics. We highlight how 11 of the top 12 priority antibiotic-resistant pathogens are known or predicted to be naturally transformable, raising the possibility that this mechanism of HGT makes significant contributions to the spread of ARGs. HGT drives the evolution of untreatable "superbugs" by concentrating ARGs together in the same cell, thus HGT must be included in strategies to prevent the emergence of resistant organisms in hospitals and other clinical settings.

Cost-effectiveness analysis of a multi-dimensional intervention to reduce inappropriate antibiotic prescribing for children with upper respiratory tract infections in China.

BACKGROUND: We developed a multifaceted intervention to reduce antibiotic prescription rate for children with upper respiratory tract infections (URTIs) among primary care doctors in township hospitals in China. The intervention achieved a 29% (95% CI 16-42) absolute risk reduction in antibiotic prescribing. This study was to assess the cost-effectiveness of our intervention at reducing antibiotic prescribing in rural primary care facilities as measured by the intervention's effect on the antibiotic prescription rates for childhood URTIs. METHODS: We took a healthcare provider perspective, measuring costs of consultation (time cost of doctor), prescription monitoring process and peer-review meetings (time cost of participants) and medication costs. Costs on provider side were collected through a bespoke questionnaire from all 25 township hospitals in December 2016, while medication costs were collected prospectively in the trial. Incremental cost-effectiveness ratios were calculated by dividing the mean difference in cost of the two trial arms by the mean difference in antibiotic prescribing rate. RESULTS: This showed an incremental cost of $0.03 per percentage point reduction in antibiotic prescribing. In addition to this incremental cost, the cost of implementing the intervention, including training and materials delivered by township hospitals, was $390.65 (SD $145.68) per healthcare facility. CONCLUSIONS: This study shows that a multifaceted intervention programme, when embedded into routine practice, is very cost-effective at reducing antibiotic prescribing in primary care facilities and has the potential of scale up in similar resource limited settings.

Clinical profile, antibiotic susceptibility pattern of bacterial isolates and factors associated with complications in culture-proven typhoid patients admitted to an urban hospital in Bangladesh.

OBJECTIVES: Typhoid fever is one of the major causes of morbidity and mortality in typhoid endemic countries like Bangladesh. However, data on the clinical and microbiological profile as well as factors associated with complications of typhoid in Bangladesh are scarce. We intended to characterise the clinical and microbiological profile of culture-proven typhoid fever and to identify factors associated with complications. METHODOLOGY: Retrospective analysis of clinical data from 431 patients with culture-confirmed typhoid fever admitted to Dhaka hospital of International Centre for Diarrhoeal Disease Research, Bangladesh, between January 2010 and December 2014. Clinical and microbiological profiles of the patients including age, sex, and duration of illness prior to hospital admission, haematological parameters and the antimicrobial resistance profile of the infecting isolate, duration of hospital stay and defervescence time were examined by logistic regression to identify the factors associated with complications. RESULT: About one of three patients were children under 5 years, and 21.5% of them were severely malnourished. During hospitalisation, 17.4% patients developed complications; mainly encephalopathy (6.7%), ileus (6.5%) and pneumonia (3.5%). Among culture-positive cases, 28.3% isolates showed multidrug resistant (MDR) and more than 90% of isolates were resistant to nalidixic acid and had intermediate sensitivity to ciprofloxacin. Five isolates were resistant to azithromycin; all isolates were sensitive to cefixime and ceftriaxone. Complication was independently associated with duration of fever before admission (adjusted odds ratio: 0.85; 95% CI: 0.074-0.97; P < 0.05), thrombocytopenia on admission (AOR: 2.84; 95% CI: 01.06-7.57; P < 0.05), duration of hospital stay (AOR: 1.34; 95% CI: 1.15-1.57; P < 0.01) and defervescence time (AOR: 0.83; 95% CI: 0.70-0.99; P < 0.05). CONCLUSION: The high prevalence of typhoid fever among under-five children and complications among hospitalised patients are matters of concern. Sensitivity of Salmonella Typhi to ceftriaxone and cefixime was better than to other conventional antibiotics. Shorter duration of fever and thrombocytopenia on admission can be considered as early signs of complications.