Outbreak Of Serratia Marcescens Research Articles

A simultaneous outbreak of Serratia marcescens and Klebsiella pneumoniae in a neonatal intensive care unit

We describe two concurrent outbreaks of Serratia marcescens and Klebsiella pneumoniae in a neonatal intensive care unit (NICU). Over a 16-month period, a total of 27 infants were either colonized (N=14) or infected (N=13). There were 15 cases of S. marcescens and 11 cases of K. pneumoniae. Both micro-organisms were involved in one fatal case. Seven preterm babies developed septicaemia, two had bacteraemia, three had respiratory infections and one had purulent conjunctivitis. The S. marcescens and K. pneumoniae isolates were investigated by three molecular methods: enterobacterial repetitive intergenic consensus polymerase chain reaction (PCR), arbitrary primed PCR with M13 primer, and random amplification of polymorphic DNA. Different patterns were found in the 16 S. marcescens epidemic isolates from 16 newborn infants. The major epidemic-involved genotype was linked to the first nine cases and this was subsequently replaced by different patterns. Eight different typing profiles were also determined for the 13 K. pneumoniae isolates from 12 newborn infants. Four K. pneumoniae bacteraemic strains proved to be identical. In conclusion, the typing results revealed that two different micro-organisms (S. marcescens and K. pneumoniae) were simultaneously involved in invasive nosocomial infections in preterm newborns. Two simultaneous clusters of cases were documented. Heterogeneous genotypes among both species were also demonstrated to be present in the NICU at the same time. A focal source for both micro-organisms was not identified but cross-transmission through handling was probably an important route in this outbreak. Strict adherence to handwashing policies, cohorting, isolation of colonized and infected patients, and rigorous environmental hygiene were crucial measures in the containment of the epidemic.

289 Containment of two Outbreaks of Serratia Marcescens in a Northern Italy NICU

S. marcescens is a recognized nosocomial pathogen especially in NICU. We describe the course and related measures of containment of two outbreaks (I-II) of S. marcescens in a 30-bed NICU. Two patients developed sepsis by S. marcescens in June 2003 following this active surveillance was established to detect infected/colonized patients and the source of the outbreak. During the outbreak period the NICU remained open to new admissions. Infected and colonized patients were cohorted in an infected area. Hygienic measures were strictly enforced for unit staff and visitors. All infants received probiotics daily. Isolates were genotyped with Pulsed Field Gel Electrophoresis (PFGE) protocol. Colonized patients were not treated with antibiotics and were discharged soon. In the period June-August 2003, 54 newborns were screened for S. marcescens, 17 (31%) infants were found colonized by S. marcescens in the digestive tract. In the same period 2 colonized patients developed sepsis from different germs (SGB, Candida albicans). In June 2004, 10 months after the first outbreak, a new fatal case of S.marcescens sepsis occurred in a VLBW in the same NICU. The following control measures revealed three (9%) colonized neonates in the Unit. By PFGE typing we identified one epidemic clone (A) in 15 infants plus the index case and two other unrelated clone (B-C) in 2 patients in outbreak I. In outbreak II one epidemic clone (D) in 3 infants and an unrelated clone in an other patient were identified. The comparative PFGE analysis excluded any relationship between the first and the second episode of sepsis and confirmed that S. marcescens was not endemic. After 6 and 2 weeks respectively the outbreaks were eradicated without any recurrence. The administration of probiotics and avoiding unnecessary exposure to antibiotics may have played an important role in the containment of the outbreak

A nosocomial outbreak of Serratia marcescens producing inducible Amp C-type beta-lactamase enzyme and carrying antimicrobial resistance genes within a class 1 integron

We investigated an outbreak of Serratia marcescens in the adult intensive care unit of the University Hospital of Napoli. The outbreak involved 13 cases of infection by S. marcescens over a nine-month period and was caused by a single pulsed-field gel electrophoresis clone. The epidemic strain was multiply antibiotic resistant, producing an inducible Amp C-type beta-lactamase enzyme and carrying the trimethoprim-resistance gene and the adenyltransferase gene, which confers resistance to streptomycin and spectinomycin, within a class 1 integron. Antimicrobial therapy with beta-lactams was associated with S. marcescens acquisition in the intensive care unit.

An Outbreak Due to Serratia marcescens in a Neonatal Intensive Care Unit Typed by 2-Day Pulsed Field Gel Electrophoresis Protocol

Background. Serratia marcescens is a well-recognized nosocomial pathogen. The objective of the study was to describe typing results using a rapid pulsed field gel electrophoresis (PFGE) protocol and infection control measures during an outbreak of Serratia marcescens in a 24-bed, referral, neonatal intensive care unit (NICU) of a tertiary-care pediatric hospital. Methods. Two patients with S. marcescens sepsis were identified in the NICU. Health care personnel of the unit were requested to reinforce infection control measures. Active surveillance was established to detect infected and/or colonized patients and environmental and staff reservoirs. Infected and colonized patients were cohorted on one side of the unit; admissions to NICU were limited. Isolates were typed with a short 2-day pulsed-field gel electrophoresis (PFGE) protocol. Results. Thirty three patients were exposed during a period of 20 days. Ten S. marcescens isolates were obtained from six patients, in two from blood culture and in three from stool culture; a single clone was identified in four. S. marcescens was not isolated from environmental or staff cultures. Conclusions. PFGE results were obtained in 2 days, infection control measures were reinforced, outbreak was promptly interrupted, and the NICU remained opened.

Nosocomial Neonatal Outbreak of Serratia marcescens: Analysis of Pathogens by Pulsed-Field Gel Electrophoresis and Polymerase Chain Reaction

Nosocomial Neonatal Outbreak of <i>Serratia marcescens</i>: Analysis of Pathogens by Pulsed-Field Gel Electrophoresis and Polymerase Chain Reaction

Source, carriers, and management of a Serratia marcescens outbreak on a pulmonary unit

An outbreak of Serratia marcescens was seen on a pulmonary ward from September 1999 until September 2000. During this period, there were two distinct clusters of S. marcescens isolation. In the first episode, September–October 1999, S. marcescens isolates with the same resistance pattern were isolated in 10 patients. PFGE (pulsed-field gel electrophoresis) following digestion with SpeI confirmed that these isolates were identical. After an initial decline in the number of isolates, the incidence rose again in March 2000. The resistance pattern of these isolates differed from that in 1999. PFGE showed that most of the isolates in 2000 were identical and had replaced the previous strain (strain 1). In the second episode, January–August 2000, 26 patients were colonized with the subsequent strain (strain 2). Three of these patients had serious clinical problems due to S. marcescens, two had bacteraemia and one empyema. In September 2000, strain 2 was also detected in stock solutions for inhalation therapy. After discontinuation of the use of stock solutions and emphasizing hygienic measures, the outbreak resolved. The majority (68%) of the patients positive for S. marcescens suffered from COPD (chronic obstructive pulmonary disease). PFGE results suggest that several COPD patients were carriers of the same strain of S. marcescens for a prolonged time. Re-admission of these patients could have lead to re-introduction of the epidemic strains.

An outbreak of Serratia marcescens bacteremia after general anesthesia.

To investigate an outbreak of Serratia marcescens bacteremia among patients after general anesthesia. A case-control study. A 304-bed, pediatric teaching hospital. Twenty-three pediatric patients who developed S. marcescens bacteremia within 2 weeks after general anesthesia between June 15 and September 22, 1999, were compared with 46 age-matched control-patients who had undergone procedures on the same clinical services of the hospital during the same period. Cases were distributed over a wide range of surgical services and were not correlated with exposure to any of the surgical, anesthesia, or nursing staff. Case-patients were significantly more likely than control-patients to have received cefazolin (odds ratio [OR], 11.1; 90% confidence interval [CI90], 1.9 to 24.3) or to have had perioperative placement of a central vascular catheter (OR, 4.2; CI90, 1.2 to 18.8). The timing of the procedures of patients who subsequently developed S. marcescens bacteremia was significantly associated with the shifts of one or more of five operating room technicians (OR, 2.9 to 6.8) who were responsible for preparing intravenous fluids used both to reconstitute perioperatively administered antibiotics and to prime central vascular catheter assemblies. Our findings are consistent with a pattern of intermittent contamination due to periodic breaches in sterile technique, rather than a point-source of contamination. The unique challenges that such a procedural breakdown presents to an epidemiologic investigation are discussed. This outbreak stresses the importance of providing comprehensive training in antisepsis when multifunctional personnel are incorporated into an operating room work environment.

Nosocomial neonatal outbreak of Serratia marcescens--analysis of pathogens by pulsed field gel electrophoresis and polymerase chain reaction.

We investigated an outbreak of Serratia marcescens in the neonatal intensive care unit (NICU) and the pediatric intensive care unit (ICU) of the University Children's Hospital Leipzig, Germany. From September to November 1998 15 patients were infected or colonized by S. marcescens. During the outbreak swabs from eye, blood, throat and nose were taken from every patient hospitalized in the ICUs. In 15 cases (14 from the NICU and one from the pediatric ICU) the cultures yielded S. marcescens. All strains were investigated by pulsed field gel electrophoresis (PFGE) as well as by polymerase chain reaction (PCR) fingerprinting. Both molecular typing methods revealed corresponding fingerprint patterns in all of the 15 isolates. Typing results of the outbreak-related isolates demonstrated that two epidemic strains of distinct genotypes were associated with cross-infections of a group of five and a group of ten patients, respectively. The three invasive and seven of the colonizing isolates were related genotypically. This survey shows that PCR and PFGE are comparable in respect to the discrimination and reproducibility for epidemiological studies of S. marcescens strains in nosocomial outbreaks. Genotypic fingerprinting of bacterial isolates is useful and important to limit nosocomial infections. Fingerprinting sources of nosocomial infections can be traced both by PFGE and PCR. All patients infected recovered completely and the nosocomial outbreak could be stopped rapidly.

Nosocomial outbreak of Serratia marcescens in a neonatal intensive care unit.

To investigate and describe an outbreak of Serratia marcescens in a neonatal intensive care unit (NICU) and to report the interventions leading to cessation of the outbreak. A 2,168-bed, tertiary-care, university teaching hospital in Vienna, Austria, with an 8-bed NICU. We conducted a case-control study to identify risk factors for colonization and infection with S. marcescens. A case-patient was defined as any neonate in the NICU with a positive culture for S. marcescens between October 1, 2000, and February 28, 2001. Polymerase chain reaction was applied to type isolates. During unannounced observations, the NICU was examined and existing policies were reviewed. Staff were reinstructed in hand antisepsis and gloving policies. Admissions were halted on December 27. During previously planned technical maintenance of the ward, the NICU was closed for 10 days and thorough aldehyde-based disinfection of the NICU was performed. Ten neonates met the case definition: 6 with infections (among them 3 with cerebral abscesses) and 4 with asymptomatic colonization. Previous antibiotic treatment of the mothers with cefuroxime was the single significant risk factor for colonization or infection (P = .028; odds ratio, 17; 95% confidence interval, 1.3 to 489.5). S. marcescens can cause rapidly spreading outbreaks associated with fatal infections in NICUs. With aggressive infection control measures, such outbreaks can be stopped at an early stage. Affected neonates themselves may well be the source of cross-infection to other patients on the ward. Antibiotic treatment of mothers should be reevaluated to avoid unnecessary exposure to antibiotics with the potential of over-growth of resistant organisms.

Three Consecutive Outbreaks of Serratia marcescens in a Neonatal Intensive Care Unit

Three Consecutive Outbreaks of <i>Serratia marcescens</i> in a Neonatal Intensive Care Unit

Three consecutive outbreaks of Serratia marcescens in a neonatal intensive care unit.

We investigated an outbreak of Serratia marcescens in the neonatal intensive care unit (NICU) of the University Hospital of Zurich. S. marcescens infection was detected in 4 children transferred from the NICU to the University Children's Hospital (Zurich). All isolates showed identical banding patterns by pulsed-field gel electrophoresis (PFGE). In a prevalence survey, 11 of 20 neonates were found to be colonized. S. marcescens was isolated from bottles of liquid theophylline. Despite replacement of these bottles, S. marcescens colonization was detected in additional patients. Prospective collection of stool and gastric aspirate specimens revealed that colonization occurred in some babies within 24 hours after delivery. These isolates showed a different genotype. Cultures of milk from used milk bottles yielded S. marcescens. These isolates showed a third genotype. The method of reprocessing bottles was changed to thermal disinfection. In follow-up prevalence studies, 0 of 29 neonates were found to be colonized by S. marcescens. In summary, 3 consecutive outbreaks caused by 3 genetically unrelated clones of S. marcescens could be documented. Contaminated milk could be identified as the source of at least the third outbreak.

An outbreak of Serratia marcescens associated with the anesthetic agent propofol

Background: In October 1999, 7 patients with postoperative infections caused by Serratia marcescens were identified at a community hospital in Ontario, Canada. We describe the investigation of this outbreak. Methods: We undertook a case-control study to determine risk factors associated with infection. Case subjects consisted of patients who had undergone surgery and acquired bacteremia or wound infections that, when cultured, grew S marcescens. Control subjects were selected from the cohort of patients who underwent surgery at the same hospital during the outbreak period. Chart reviews were conducted for case and control subjects. Environmental samples were taken from medications and liquids in the operating rooms and from one health care professional who was involved in all the cases. S marcescens isolates were forwarded to a reference laboratory for pulsed field gel electrophoresis. Results: We identified 7 case subjects and 29 control subjects. Five patients had bacteremia and 2 patients had wound infections. Two patients with bacteremia died. All patients with bacteremia or wound infections were exposed to a single anesthetist (anesthetist A) and were administered the anesthetic medication propofol. These patients were more than 40 times more likely to have had anesthetist A administer their anesthetic (OR 41.6, 95% CI 3.6–1120) and 22 times more likely to have received propofol (OR 22, 95% CI 2.1–550) than were control subjects. None of the environmental samples or cultures from anesthetist A were positive for S marcescens. Six of the 7 human isolates had an identical pulsed field gel electrophoresis pattern, and the seventh was untypeable. Conclusions: This outbreak of postoperative infections was very strongly linked to the use of propofol by one anesthetist. Health care professionals must follow strict aseptic techniques when using propofol and should review these techniques regularly.

An outbreak of Serratia marcescens in two neonatal intensive care units

Outbreaks of infection in neonatal intensive care units (NICUs) due to Serratia marcescens are well recognized. In some outbreaks no point source has been found, whereas in others cross-infection has been associated with contaminated ventilator equipment, disinfectants, hands and breast pumps. We report an outbreak due to S. marcescens that involved two geographically distinct NICUs. The outbreak occurred over a six week period; 17 babies were colonized, 12 at Glasgow Royal Maternity Hospital (GRMH) and five at the Queen Mothers Hospital (QMH). At GRMH three babies developed septicaemia, of whom two died. The outbreak isolates were of the same serotype and phage type and were indistinguishable on the basis of restriction fragment length polymorphism analysis. During the outbreak, two babies shown consistently to be negative on screening, were transferred between the two units. In addition, two members of medical staff attended both units. In QMH no means of cross infection was identified. However, in GRMH the outbreak strain of S. marcescens was isolated from a laryngoscope blade and a sample of expressed breast milk.

An outbreak of multiply resistant Serratia marcescens: the importance of persistent carriage.

An outbreak of multi-resistant Serratia marcescens involving 24 patients occurred in a bone marrow transplant and oncology unit, from September 1998 to June 1999, of whom 14 developed serious infection. This is the first such outbreak described in a BMT unit. All isolates demonstrated the same antimicrobial susceptibility pattern and were the same unusual serotype O21:K14. The antimicrobial susceptibility profile showed reduced susceptibility to ciprofloxacin, gentamicin and piperacillin-tazobactam. As the latter two antimicrobials are part of our empiric therapy for febrile neutropenia, they were substituted with meropenem and amikacin during the outbreak. Investigation revealed breaches in infection control practices. Subsequently, the outbreak was contained following implementation of strict infection control measures. A prominent feature of the outbreak was prolonged carriage in some patients. These patients may have acted as reservoirs for cross-infection. This report also indicates that patients who become colonised with Serratia marcescens may subsequently develop invasive infection during neutropenic periods.

Use of molecular epidemiology to investigate an outbreak of Serratia marcescens in a Neonatal Intensive Care Unit (NICU)

Use of molecular epidemiology to investigate an outbreak of Serratia marcescens in a Neonatal Intensive Care Unit (NICU)

Epidemiological Analysis Defining Concurrent Outbreaks of Serratia marcescens and Methicillin-Resistant Staphylococcus aureus in a Neonatal Intensive-Care Unit

To describe the epidemiology, interventions, and molecular typing methods used during the investigation and control of concurrent outbreaks of Serratia marcescens and methicillin-resistant Staphylococcus aureus (MRSA) infections in a neonatal intensive-care unit (NICU). A 206-bed women's and infants' hospital with a 48-bed NICU. A 22-week, prospective, descriptive study of all NICU infants with S marcescens or MRSA infection or colonization. Repetitive polymerase chain reaction (rep PCR) and pulsed-field gel electrophoresis (PFGE), respectively, were applied to the typing of S marcescens and MRSA isolates. Infants with S marcescens or MRSA infection or colonization were placed in isolation; all other infants were cohorted. A multidisciplinary task force implemented education for all hospital and medical staff regarding policies essential for outbreak control. Changes in physical setting and patient contact procedure were required to promote adherence to existing policies. Two premature infants had S marcescens infection, and five were colonized; rep PCR verified that both invasive and three of five colonizing isolates were related genotypically. Five bacteremic and 10 MRSA-colonized infants were identified; PFGE confirmed that 12 of the isolates had similar electrophoretic patterns. S marcescens infection was eliminated from the NICU 3 weeks after interventions were initiated. MRSA infections also were eliminated, and MRSA colonization fell to below pre-outbreak rates within 8 weeks. Despite a 100% increase in NICU patient days per month during the subsequent 2 years, no further clusters of S marcescens or MRSA infection have occurred. Concurrent outbreaks of S marcescens and MRSA in an NICU were confirmed by genotyping of strains. Control was achieved by isolation and cohorting of patients and strict adherence to NICU policies and procedures.

Epidemiological Analysis Defining Concurrent Outbreaks of Serratia marcescens and Methicillin-Resistant Staphylococcus aureus in a Neonatal Intensive-Care Unit

Objective To describe the epidemiology, interventions, and molecular typing methods used during the investigation and control of concurrent outbreaks of Serratia marcescens and methicillin-resistant Staphylococcus aureus (MRSA) infections in a neonatal intensive-care unit (NICU). Setting A 206-bed women's and infants' hospital with a 48-bed NICU. Design A 22-week, prospective, descriptive study of all NICU infants with S marcescens or MRSA infection or colonization. Repetitive polymerase chain reaction (rep PCR) and pulsed-field gel electrophoresis (PFGE), respectively, were applied to the typing of S marcescens and MRSA isolates. Interventions Infants with S marcescens or MRSA infection or colonization were placed in isolation; all other infants were cohorted. A multidisciplinary task force implemented education for all hospital and medical staff regarding policies essential for outbreak control. Changes in physical setting and patient contact procedure were required to promote adherence to existing policies. Results Two premature infants had S marcescens infection, and five were colonized; rep PCR verified that both invasive and three of five colonizing isolates were related genotypically. Five bacteremic and 10 MRSA-colonized infants were identified; PFGE confirmed that 12 of the isolates had similar electrophoretic patterns. S marcescens infection was eliminated from the NICU 3 weeks after interventions were initiated. MRSA infections also were eliminated, and MRSA colonization fell to below pre-outbreak rates within 8 weeks. Despite a 100% increase in NICU patient days per month during the subsequent 2 years, no further clusters of S marcescens or MRSA infection have occurred. Conclusions Concurrent outbreaks of S marcescens and MRSA in an NICU were confirmed by genotyping of strains. Control was achieved by isolation and cohorting of patients and strict adherence to NICU policies and procedures.

Epidemiological Analysis Defining Concurrent Outbreaks of Serratia Marcescens and Methicillin-Resistant Staphylococcus Aureus in a Neonatal Intensive-Care Unit

To describe the epidemiology, interventions, and molecular typing methods used during the investigation and control of concurrent outbreaks of Serratia marcescens and methicillin-resistant Staphylococcus aureus (MRSA) infections in a neonatal intensive-care unit (NICU).A 206-bed women's and infants' hospital with a 48-bed NICU.A 22-week, prospective, descriptive study of all NICU infants with S marcescens or MRSA infection or colonization. Repetitive polymerase chain reaction (rep PCR) and pulsed-field gel electrophoresis (PFGE), respectively, were applied to the typing of S marcescens and MRSA isolates.Infants with S marcescens or MRSA infection or colonization were placed in isolation; all other infants were cohorted. A multidisciplinary task force implemented education for all hospital and medical staff regarding policies essential for outbreak control. Changes in physical setting and patient contact procedure were required to promote adherence to existing policies.Two premature infants had S marcescens infection, and five were colonized; rep PCR verified that both invasive and three of five colonizing isolates were related genotypically. Five bacteremic and 10 MRSA-colonized infants were identified; PFGE confirmed that 12 of the isolates had similar electrophoretic patterns. S marcescens infection was eliminated from the NICU 3 weeks after interventions were initiated. MRSA infections also were eliminated, and MRSA colonization fell to below pre-outbreak rates within 8 weeks. Despite a 100% increase in NICU patient days per month during the subsequent 2 years, no further clusters of S marcescens or MRSA infection have occurred.Concurrent outbreaks of S marcescens and MRSA in an NICU were confirmed by genotyping of strains. Control was achieved by isolation and cohorting of patients and strict adherence to NICU policies and procedures.

Repeated epidemics caused by extended-spectrum beta-lactamase-producing Serratia marcescens strains.

An outbreak of Serratia marcescens involving 42 patients admitted to the general intensive care unit of the Hospital of Varese, Italy, occurred from March 1994 to August 1995. The causative strains were resistant to oxyimino-cephalosporins and monobactams due to their production of an extended-spectrum beta-lactamase. Another outbreak caused by Serratia marcescens strains had occurred in the same unit a few months earlier, from February to October 1993, with the strains involved producing a novel TEM-derived extended-spectrum beta-lactamase. In order to verify whether there were any relationships between isolates from the two epidemics, the strains and their enzymes were characterized. Biochemical data and gene amplification experiments showed that the isolates of the second outbreak harbored a non-conjugative plasmid of approximately 48 kb, codifying for the production of an SHV-derived extended-spectrum beta-lactamase with pI 8.2. Restriction fragment length polymorphism analysis of total genomic DNA by pulsed-field gel electrophoresis of Serratia marcescens isolates unambiguously identified two different bacterial clones responsible for the two epidemics. Epidemiological and microbiological investigations demonstrated the long persistence of Serratia marcescens strains and their circulation in other hospital wards, thus suggesting their possible role as a long-term reservoir for further epidemic spread.

Serratia marcescens Outbreak Associated with Extrinsic Contamination of 1% Chloroxylenol Soap

Serratia marcescens Outbreak Associated with Extrinsic Contamination of 1% Chloroxylenol Soap