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[Infection control and prevention in intensive care: environmental aspects].

Surveillance is understood as the monitoring over time of the onset of preventable infection and/or microbial colonization in patients in intensive care units (ICU), where the prevalence of nosocomial infections, particularly those caused by microorganisms multiresistant to antibiotics, is alarmingly high. Surveillance deals with: 1) pathogens responsible for infection and their patterns of antibiotic resistance; 2) epidemics; 3) endemic infections selected according to predictability; 4) frequency of use of specific invasive procedures, where the greater the use, the higher the frequency of nosocomial infections associated with them; 5) use of antibiotics. Surveillance is operated through: 1) the microbiology laboratory, which is responsible for accurate surveillance of hospital infections; 2) the active surveillance on the wards, which concerns: a) identification of infections either on admission or during hospitalization or both, b) use of invasive procedures, control of parameters, and data collection, c) type of patients treated, identification of infected patients and data analysis and interpretation. Infection prevention complementary to surveillance starts with the adoption of strategies and interventions based on the application of universal precautions and/or on the route of transmission. A crucial point is the sterilization and disinfection of medical devices. In recent years there has been a steady rise in the number of infections caused by medical devices, most likely because of the increasing use of sophisticated and complex equipment that is often difficult to decontaminate and because of the rise in the number of immunocompromised patients or those susceptible to infections.

Critical Care↗

Antibiotic activity of telithromycin and comparators against bacterial pathogens isolated from 3,043 patients with acute exacerbation of chronic bronchitis.

BACKGROUND: Antimicrobial therapy is considered an important component in the medical management of most patients with acute exacerbation of chronic bronchitis (AECB). The three predominant bacterial species isolated are nontypeable Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae. Staphylococcus aureus is also frequently isolated while atypical bacteria are thought to cause up to 10% of exacerbations. Antibacterial resistance is increasing worldwide and little surveillance data exist concerning pathogens isolated from patients with AECB. METHODS: This study examines the prevalence of antibacterial resistance in isolates obtained from patients with clinically diagnosed AECB. A total of 3043 isolates were obtained from 85 centres in 29 countries, between 1999-2003, and were tested against the new ketolide telithromycin and a panel of commonly used antibiotics. RESULTS AND DISCUSSION: Of the S. pneumoniae isolates, 99.9% were susceptible to telithromycin, but only 71% were susceptible to erythromycin and 75.3% to penicillin. Of the H. influenzae isolates, 99.6% were susceptible to telithromycin. 11.7% of these isolates produced beta-lactamase. Almost 10% of S. pneumoniae were multidrug-resistant; 99.0% of these isolates were susceptible to telithromycin. Telithromycin also demonstrated good in vitro activity against M. catarrhalis (MIC90 = 0.12 mg/L) and was the most active compound against methicillin-susceptible S. aureus (98.9% susceptible). CONCLUSION: Telithromycin demonstrated similar or better activity against the bacterial species investigated than the other agents, with the most complete coverage overall. These species are the predominant causative bacterial pathogens in AECB and thus the spectrum of activity of telithromycin makes it a potential alternative for the empirical treatment of AECB.

Adult↗

Antimicrobial susceptibilities of potential bacterial pathogens in adults with acute respiratory tract infections Prospective Epidemiological Network Investigating Community-acquired Infection SurveiLLance In Nagasaki (PENICILLIN) Study.

The prevalence and the antimicrobial susceptibilities of bacterial pathogens in acute upper respiratory tract infections (AURTIs) is not clear. We conducted a prospective community-based multicenter study in 45 centers across Nagasaki, Japan, between December 2001 and April 2002. We examined the nasopharyngeal or throat isolates in 930 adult outpatients with AURTIs. Potential bacterial pathogens, including Streptococcus pyogenes (from 6.8% patients), S. pneumoniae (5.3%), S. milleri group (2.0%), Staphylococcus aureus (26.0%), Moraxella catarrhalis (7.4%), Haemophilus influenzae (17.6%), and Klebsiella pneumoniae (1.2%), were isolated from 51.8% of the patients. Penicillin nonsusceptible phenotype accounted for 44.9% of S. pneumoniae isolates. Among Staphylococcus aureus isolates, 9.1% were methicillin-resistant. In H. influenzae isolates, 6.7% produced beta-lactamase and 23.2% were beta-lactamase-negative ampicillin-resistant. The results indicated that the potential bacterial pathogens were detected in the remarkable population of the adults with AURTIs and the current antimicrobial susceptibilities of such pathogens.

Acute Disease↗

In vitro activity of 19 antimicrobial agents against 3513 nosocomial pathogens collected from 48 Canadian medical centres. The Canadian Antimicrobial Study Group.

Antimicrobial resistance is a global concern. Differentiation between susceptibility rates for nosocomial versus community pathogens is important epidemiologically because it impacts on the appropriate empirical selection of antimicrobial therapy for infected patients. We studied resistance rates for 3513 nosocomial pathogens from 48 Canadian medical centres tested against 19 antimicrobial agents. The following are percent susceptibility for ceftazidime, ceftriaxone, ciprofloxacin, imipenem, netilmicin, and ticarcillin/clavulanic acid, respectively: Enterobacteriaceae 95, 95, 97, 99 98, 89; Escherichia coli, all 99 except ticarcillin/clavulanic acid (91); Enterobacter spp. 78, 78, 96, 99, 99, 71; Citrobacter spp. 79, 80, 89, 100, 94, 73; Proteus spp. 99, 88, 99, 88, 99, 98; Pseudomonas aeruginosa 88, 20, 82, 88, 81, 36; Staphylococcus aureus, all > 95; Enterococcus spp. 4, 9, 62, 95, 43, 38. Susceptibility rates for other species of microorganisms and agents tested varied considerably. Some institutions had higher than average resistance rates for some pathogens (i.e. P. aeruginosa) and some agents. Detection and continued surveillance of antimicrobial resistance amongst nosocomial pathogens is vital to patient care and health care resources. The control of antimicrobial resistance can help maintain antibiotic usage and costs associated with the use of ever more potent drugs and the treatment of increasingly resistant infections.

Canada↗

[Continuous surveillance of antimicrobial resistance among nosocomial gram-negative bacilli from intensive care units in China].

OBJECTIVE: To investigate the change of antimicrobial resistance among nosocomial gram-negative bacilli, especially those of Enterobacteriaceae isolated from intensive care units from 1994 to 2001 in China. METHODS: E test was made to determine the minimal inhibitory concentrations (MIC) of 10 279 isolates of gram-negative bacilli (including 5 829 strains of bacilli of Enterobacteriaceae) from 32 hospitals in China from 1994 to 2001. RESULTS: The most common pathogens were Pseudomonas aeruginosa; Escherichia coli, Klebsiella spp, Acinetobacter spp. Enterobacter spp, and Stenotrophomonas maltophilia. The most common pathogens in respiratory tract specimens were Pseudomonas aeruginosa (25%), Klebsiella pneumoniae (18%), and Acinetobacter baumanni (11%). The most common pathogens in blood and urine specimens were Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The antibiotic remaining the most active against all of the gram-negative bacilli for 7 years was imipenem (with a susceptibility rate of 87%), followed by cefoperazone/sulbactam (however, with a susceptibility rate decreasing from 86% to 75%), amikacin (75%), ceftazidime (73%), cefepime (72%), and piperacillin/tazobactam (71%). The susceptibility rate of Escherichia coli Klebsiella pneumoniae to imipenem remained 98% with a MIC(90) of 0.5 micro g/ml during the 7 years, much higher than those to amikacin (84%), ceftazidime (83%), cefoperazone/sulbactam (83%), piperacillin/tazobactam (80%), and cefepime (80%). The susceptibility rate of these two species to cefoperazone/sulbactam decreased from 90% in 1996 to 74% in 2001. While the susceptibility to cefotaxime and ceftriaxone decreased from 82% to 57%. The susceptibility rate of Escherichia coli to ciprofloxacin decreased from 54% to 25% and that of Klebsiella pneumoniae to ciprofloxacin decreased from 90% to 75%. The prevalence of extended spectrum beta-lactamases in these two species increased from 11% in 1994 to 34% in 2001. The most active antibiotics against Enterobacter cloacae were imipenem, cefepime, amikacin with the susceptible rates of 95%, 76%, and 70%, respectively; the susceptibility rates of Citrobacter freundii to imipenem, cefepime, amikacin, and cefoperazone/sulbactam were 94%, 80%, 80%, and 78% respectively. Only 40% approximately 60% isolates of Enterobacter cloacae and Citrobacter freundii were susceptible to third-generation cephalosporins. CONCLUSION: Imipenem remains highly active against Enterobacteriaceae, but the activities of other antibiotics have decreased in recent years.

Anti-Bacterial Agents↗

Using mandatory data collection on multiresistant bacteria for internal surveillance in a hospital.

OBJECTIVES: Multiresistant pathogens cause major clinical problems and considerably increase treatment costs. Since 2001 the Protection Against Infection Act (PIA) obligates hospitals in Germany to the documentation of multiresistant bacteria. We analyzed the use of these data for routine internal surveillance. METHODS: We used standard data collected for the mandatory documentation and studied consecutive diagnoses of Methicillin-resistant Staphylococcus aureus (MRSA) in a 893-bed tertiary level hospital in North Rhine-Westphalia in Germany. Based on the Poisson distribution for the cumulative yearly incidence of MRSA, we defined a threshold level for an outbreak. RESULTS: During a 12-month time period 80 patients were diagnosed with MRSA. The time structure and spatial distribution of different MRSA phenotypes (defined through specific antibiotic resistance patterns) were consistent with the within-hospital transmission. In the two preceding time periods of 12 months each, 15 respectively 8 patients with MRSA were found. The defined alert threshold level for cumulative yearly incidence was crossed in the beginnings of the outbreak. CONCLUSION: Monitoring the mandatory data collected on multiresistant bacteria allows the early detection of accumulations suspect for the within-hospital transmission. This knowledge can be used for a fast reaction and breaking off the transmission chains.

Data Collection↗

Plant disease resistance: commonality and novelty in multicellular innate immunity.

Pathogen avirulence genes encode for effector molecules that play a crucial role in the process of pathogen colonization of plant tissue. Successful host defense requires rapid and efficient detection of the pathogen avirulence factors. In the last few years, much progress has been made in delineating the plant molecular sentinels that participate in pathogen identification. Because this ability is genetic information that is 'hard-wired' into the genome, it is called 'innate immunity' and it draws its origins from a phylogenetically ancient form of immunity common to plants and animals. Conservation is shown in many of the functional molecular motifs of innate genes such as the Toll/interleukin 1 receptor domains, nucleotide binding domains and structures that contain leucine rich repeats. Novel plant molecular surveillance domains also include pathogen pattern recognition by coiled-coil domains and specialized kinases. The rapid evolution of plant innate immunity genes is readily detected in their sequence polymorphism, by their massive amplification and appearance in the genome in a clustered organization. By comparative biology of highly diverged innate immunity systems we can enhance our appreciation of the truly basic forces that have shaped its evolution in mutlicellular organisms.

Amino Acid Sequence↗

Occurrence and antimicrobial susceptibility patterns of pathogens isolated from skin and soft tissue infections: report from the SENTRY Antimicrobial Surveillance Program (United States and Canada, 2000).

A total of 1,404 bacterial isolates were recovered from skin and soft tissue infections (SSTIs) from hospitalized patients in 24 sites in the United States (US) and 5 Canadian medical centers as part of the SENTRY Antimicrobial Surveillance Program. Isolates were collected between October and December, 2000. The rank order of pathogens was: Staphylococcus aureus (45.9%), Pseudomonas aeruginosa (10.8%), Enterococcus spp. (8.2%), Escherichia coli (7.0%), Enterobacter spp. (5.8%) and Klebsiella spp. (5.1%). The same order was observed in the US and Canada. Of note, almost 30% of S. aureus were oxacillin-resistant. Vancomycin resistance among enterococci was low (7.8%) representing a marked decrease from earlier SENTRY Program reports. Several antimicrobial agents remained very active against P. aeruginosa and Enterobacteriaceae isolates. In particular amikacin, cefepime, and the carbapenems (imipenem and meropenem) showed an excellent spectrum of activity (>95% susceptible). Extended-spectrum beta-lactamase production was observed in both E. coli (7.1%) and Klebsiella spp. (11.3%). Cefepime remained highly active, even against ceftazidime-resistant isolates of Enterobacter spp. The results of this study have identified the most common causes of SSTIs in hospitalized patients in North America, and can be used to make informed decisions concerning standards of empiric treatment for SSTIs in this region.

Anti-Bacterial Agents↗

Mapping Wastewater Pathogens and Their Associated Environmental and Public Health Risk Factors: A Systematic Review and Meta-Analysis.

BACKGROUND: Wastewater-based epidemiology (WBE) has emerged as a critical tool for public health surveillance, yet its application across diverse pathogens and geographical settings remains inconsistent. This systematic review synthesizes global evidence on wastewater surveillance to identify associated risk factors. METHODS: Following PRISMA 2020 guidelines (PROSPERO: CRD420261297382), a systematic search was conducted across PubMed, Scopus, Google Scholar, and Web of Science for studies published between 2000 and 2025. RESULTS: Thirty-nine peer-reviewed studies were included. The evidence base is geographically skewed toward the European Region (48.7%) and the Americas (23.1%), with significant underrepresentation in LMICs. Viruses were the primary biological target (89.7%), followed by bacteria (7.7%) and parasites (2.6%). A proportion meta-analysis of 31 eligible studies demonstrated a pooled wastewater pathogen detection prevalence of 62% (95% CI: 47.5-74.6%), with the European Region yielding the highest regional estimate (73%) and the African Region the lowest (8.3%). Conventional PCR and sequencing methods showed higher pooled detection rates (92.4% and 90.1%, respectively) than RT-qPCR (47.9%). CONCLUSION: WBE provides a robust early-warning system indicating a need for broader pathogen diversity, incorporating bacterial and parasitic surveillance and expansion into rural and resource-limited regions.

Contamination↗

Comparative genomic epidemiology of food- and patient-derived diarrheagenic Escherichia coli from sentinel surveillance in Southeast China.

Diarrheagenic Escherichia coli (DEC) remains an important foodborne pathogen, yet long-term comparative genomic surveillance data jointly characterizing food-derived and patient-derived isolates remain limited. This surveillance-based comparative study integrated antimicrobial susceptibility testing and whole-genome sequencing to characterize diarrheagenic Escherichia coli isolates recovered from food and patient sources in Lishui, Southeast China, during 2018-2025, with emphasis on occurrence, resistance profiles, genomic backgrounds, and plasmid replicon-associated features. Antimicrobial susceptibility testing was performed for 258 selected isolates, and whole-genome sequencing was conducted for a curated analytical subset of 204 isolates. The sequenced subset was used for diversity-oriented comparative genomic analysis rather than for unbiased prevalence estimation of the entire DEC collection. EAEC predominated in both sources, although food-associated occurrence was heterogeneous across categories, with the highest recovery rate observed in raw meat. Patient-derived isolates showed a broader overall resistance burden, whereas food-derived isolates retained substantial resistance to tetracycline, chloramphenicol, and florfenicol. Phylogenetic analysis showed partial overlap in genomic backgrounds between food-derived and patient-derived isolates, while representative resistance determinants displayed both broadly distributed and lineage-enriched patterns. Replicon-based plasmid profiling identified 42 plasmid types, including 12 detected in both sources, with IncF-related replicons predominating among these shared profiles. Several food-derived isolates carried multiple plasmid replicon types that were also observed in patient-derived isolates. Overall, food-derived and patient-derived DEC showed partial overlap in genomic backgrounds, resistance determinants, and replicon-defined plasmid profiles within this surveillance setting, while retaining source-associated heterogeneity. These findings should be interpreted as surveillance-based comparative evidence rather than as evidence of direct source attribution or transmission.

Humans↗

Bacteriological findings in patients with bone marrow transplantation (Karl Marx University Leipzig, 1985-1987).

The results of the bacteriological surveillance cultures for 26 patients with bone marrow transplantation (Karl Marx University Leipzig, G.D.R., 1985-1987) are presented. 5.9% of all surveillance cultures contained facultatively pathogenic germs (with Pseudomonas aeruginosa as the most frequent representative, which was the reason of a sepsis in two patients). Coagulasenegative Staphylococci and other germs with an obscure pathogenicity were isolated upon a large scale, especially from the mucous membrane regions. There are hints, that above all special strains of coagulasenegative Staphylococci "colonize" the patient's body (also for longer periods) and turn into the blood too. During the total decontamination intestinal anaerobic flora is absent. After closing of total decontamination Clostridium perfringens is the first detectable anaerobic species. During the selective decontamination systemic applications of antibiotics are able to obliterate anaerobic findings for certain periods. Recommendations for an effective arrangement of the surveillance cultures of bone marrow transplantation patients are given.

Anti-Bacterial Agents↗

[Epidemiology and sensitivity to antibiotics in paediatric respiratory infections over a 4-year period. Retrospective study of 460 H. influenzae, S. pneumoniae and M. catarrhalis strains]

H. influenzae, S. pneumoniae and M. catarrhalis are the most common bacterial pathogens causing respiratory infections in children. Resistance to antibiotics may vary according to the geographical area. It is therefore important that the resistance pattern of such pathogens is determined by surveillance studies carried out both on a national scale and by individual laboratories. In this study, we determined retrospectively the prevalence of H. influenzae, S. pneumoniae and M. catarrhalis in upper respiratory tract infections involving subjects of paediatric age, with reference to the type of clinical sample (pharingeal swab and nasal swab), symptomatology and age group. Moreover, for the above micro-organisms the pattern of sensitivity to antibiotics was assessed. In the observation period (January 1996-December 1999), at the day hospital of the Paediatric Pneumology Division of the Gaslini Institute in Genova, in 476 patients between 0 and 15 years of age a total of 460 respiratory pathogens were isolated: 164 S. pneumoniae strains, 163 of H. influenzae (96 belonging to type B and 67 non-attributable to any type) and 133 of M. catarrhalis. As regards sensitivity to antibiotics, ceftriaxone and amoxycillin/clavulanic acid proved to be the most active molecules in all the studied strains.

Journal Article↗

Nosocomial enterococci resistant to vancomycin--United States, 1989-1993.

As part of continual surveillance for antibiotic resistance among pathogens associated with nosocomial infections, a recent analysis of data reported to CDC's National Nosocomial Infections Surveillance (NNIS) system demonstrated a 20-fold increase in the percentage of enterococci associated with nosocomial infections that are resistant to vancomycin from January 1, 1989, through March 31, 1993. Many of these strains are resistant to all available antimicrobial agents. This report summarizes that analysis.

Cross Infection↗

Detection of Babesia microti by polymerase chain reaction.

Human babesiosis, which is caused by infection with the intraerythrocytic malarialike protozoan Babesia microti, has recently been diagnosed with increasing frequency in residents of New England. Diagnosis is difficult because of the small size of the parasite and the sparse parasitemia that is characteristic of most infections with this pathogen. We generated B. microti-specific DNA sequence information by universal primer amplification of a portion of the eukaryotic 16S-like gene; this was followed by direct DNA sequence analysis. Specific primers were synthesized on the basis of this sequence information for use in the polymerase chain reaction (PCR). The PCR-based system demonstrates a strong bias for detection of B. microti as opposed to Babesia gibsoni and does not amplify vertebrate DNA. The analytical sensitivity of the system is approximately three merozoites. Blood specimens from 12 patients with clinically diagnosed and parasitologically confirmed babesiosis from Nantucket Island, Mass., were PCR positive in a blinded test of this procedure. Thus, DNA amplification may provide an adjunct to conventional methods for the diagnosis of human babesiosis and may provide a new means of monitoring therapy or enhancing epidemiological surveillance for this emerging pathogen.

Animals↗

Antibiotic resistance in long-term acute care hospitals: the perfect storm.

OBJECTIVE: To examine bacterial antibiotic resistance and antibiotic use patterns in long-term acute care hospitals (LTACHs) and to evaluate effects of antibiotic use and other hospital-level variables on the prevalence of antibiotic resistance. DESIGN: Multihospital ecologic study. METHODS: Antibiograms, antibiotic purchasing data, and demographic variables from 2002 and 2003 were obtained from 45 LTACHs. Multivariable regression models were constructed, controlling for other hospital-level variables, to evaluate the effects of antibiotic use on resistance for selected pathogens. Results of active surveillance in 2003 at one LTACH were available. RESULTS: Among LTACHs, median prevalences of resistance for several antimicrobial-organism pairs were greater than the 90th percentile value for National Nosocomial Infections Surveillance system (NNIS) medical intensive care units (ICUs). The median prevalence of methicillin resistance among Staphylococcus aureus isolates was 84%. More than 60% of patients in one LTACH were infected or colonized with methicillin-resistant S. aureus and/or vancomycin-resistant Enterococcus at the time of admission. Antibiotic consumption in LTACHs was comparable to consumption in NNIS medical ICUs. In multivariable logistic regression modeling, the only significant association between antibiotic use and the prevalence of antibiotic resistance was for carbapenems and imipenem resistance among Pseudomonas aeruginosa isolates (odds ratio, 11.88 [95% confidence interval, 1.42-99.13]; P=.02). CONCLUSIONS: The prevalence of antibiotic resistance among bacteria recovered from patients in LTACHs is extremely high. Although antibiotic use in LTACHs likely contributes to resistance prevalence for some antimicrobial-organism pairs, for the majority of such pairs, other variables, such as prior colonization with and horizontal transmission of antimicrobial-resistant pathogens, may be more important determinants. Further research on antibiotic resistance in LTACHs is needed, particularly with respect to determining optimal infection control practices in this environment.

Anti-Bacterial Agents↗

The role of the microbiology laboratory in surveillance and control of nosocomial infections.

The microbiology laboratory's rapid and consistent identification of nosocomial pathogens is a keystone in the surveillance and control of hospital-acquired infections. In addition, the laboratory serves as a source of expert consultation for clinicians and infection control personnel and as an "early warning center" for infection problems. In making its contributions to infection control most effective, the laboratory must recognize its capabilities and limitations, must insure that the materials and methods it uses and the specimens it processes meet high standards, must provide retrievable records, and must have a good working knowledge of microbiologic technics used to evaluate both endemic and epidemic infections. Moreover, because laboratory workers come into contact daily with potentially infectious specimens and isolates, the laboratory's contributions to infection control should also include the prevention and surveillance of laboratory-acquired infections.

Cross Infection↗

Mycobacterium bovis infections in San Diego: a clinicoepidemiologic study of 73 patients and a historical review of a forgotten pathogen.

We have presented 73 patients (48 adults and 25 children) with microbiologically documented M. bovis infections identified over the 12-year period from 1980 through 1991. Epidemiologic investigation of these patients revealed that the majority (80%) were of Hispanic origin. The non-Hispanic patients either had traveled extensively outside the United States, were born in the United States during its endemic period or in other countries with endemic bovine tuberculosis, or were exposed to a close relative with a positive PPD and known exposure to M. bovis. For Hispanic patients, the presence of reactivation disease in adults and primary disease in children indicate that this mycobacterium remains endemic in Mexican beef and dairy herds, a position supported by United States monitoring of Mexican cattle transferred across the border. Our review of the historical and contemporary efforts to eradicate this animal and human pathogen from the livestock industry in the United States and abroad shows that the implementation of similar methods could be effective in Mexico. The detailed presentations of selected patients and summaries of the clinical manifestations in the remainder of our 73 patients reveal striking similarities to historical accounts and to more contemporary studies of reactivated disease in England. Although M. bovis infections are still expressed predominantly in extrapulmonary sites (cervical and mesenteric nodes, the peritoneum, and the GU tract), as many as 50% of adult patients will present only with pulmonary disease. Underlying immunosuppressive disorders were particularly prominent in adults with extrapulmonary disease. For example, HIV positive patients accounted for 12 of 48 adults and 1 adolescent patient in our series. Overall, M. bovis infections accounted for almost 3% of all tuberculous disease reported in San Diego County during the study period. The intrinsic resistance of M. bovis to PZA could threaten the response of patients with bovine tuberculosis to the short-course chemotherapeutic regimens now recommended by the CDC and the American Thoracic Society. We strongly recommend continued surveillance for this forgotten pathogen because the importation of Mexican cattle, the migration of Hispanic immigrants from border areas to the United States interior, and the persistence of extrapulmonary disease in immunocompetent and HIV-infected United States citizens assure its persistence in this country.

Acquired Immunodeficiency Syndrome↗