Cohorting Of Patients Research Articles

Two nosocomial norovirus outbreaks in the neonatal intensive and intermediate care unit

Norovirus is one of the major causes of non-bacterialacute gastroenteritis worldwide. Diagnostic methods in-clude electron microscopy, enzyme-linked immunosorbentassay (ELISA) and reverse-transcription polymerase chainreaction (RT-PCR) [1]. Electron microscopy has previous-ly been regarded as the gold standard for the diagnosis ofnorovirus, but RT-PCR appears to be a more sensitiveassay (36 to 58% versus 94 to 98%), with similarspecificity(96to98%and92to100%)[2, 3]. Studieson the sensitivity and specificity of the RIDASCREENenzyme immunoassay reported a broad range of 36 to 59%and73to100%,respectively[4, 5] (CDC, Atlanta, GA,USA). However, data for preterm and term born babies israre. Recent studies of norovirus in very young infantshave presumed many false-positive results and havequestioned the high specificity of enzyme immunoassay[2, 6]. The aim of this report is to characterise twooutbreaks of norovirus in neonatal nurseries by raisingquestions about the performance of diagnostic assays fornorovirus and the clinical presentation of norovirusinfectioninveryyounginfants.Faecal specimens of all tested persons were sent to theInstitute of Hygiene, Microbiology and EnvironmentalMedicine of the Medical University of Graz immediatelyafter collection or on the following day. Analysis wasdone for norovirus, adenovirus and rotavirus using anenzyme immunoassay (RIDASCREEN Norovirus ELISAkit, 3rd Generation) and/or real-time PCR (ANDIATECNorovirus real-time PCR kit, Bioproducts Company,designed to detect norovirus genotypes I and II). There-fore, stool cultures on bacteria and parasites were alsodone. To assess the clinical severity of disease, a 14-pointscoring system by Colomba et al. [7] was used. Duringboth outbreaks, the clinical records of all patients werecarefully documented and strict hygienic measures, in-cluding the cohorting of patients, mandatory use of glovesand gowns, and hand washing with disinfecting agents(Skinman® Soft N, Ecolab, Vienna, Austria), wereimplemented at the particular unit. Approval by theEthical Review Board was not necessary since the studywas performed by means of prospective surveillanceinvolving both outbreaks.First outbreak: January to March 2007In January 2007, a neonatologist on duty developedsymptoms of gastroenteritis, including fever, vomiting anddiarrhoea. The day after, the index patient (see Table 1),hospitalized at the Neonatal Intensive Care Unit (NICU) ofthe Pediatric Department of the Medical University Hospi-tal of Graz, Austria, recalled symptoms of bloody tingedstools for one day (14-point severity score: 6). Faecalspecimens of this infant and of the staff member were testedon virus, bacteria and parasites, and turned out to bepositive for norovirus tested by ELISA. Subsequently,faecal specimens of all neonates admitted to and treated atthe NICU were routinely tested three times a week byELISA and, due to repeatedly positive results, some of thespecimens were additionally tested by RT-PCR.

Infection Control Challenges in Deployed US Military Treatment Facilities

Personnel sustaining combat-related injuries in current overseas conflicts continue to have their care complicated by infections caused by multidrug-resistant organisms, including Acinetobacter, Klebsiella, and Pseudomonas. Although presumed to be due to multiple factors both within and outside of the combat theater, concern has been raised about the difficulties in establishing and maintaining standard infection control (IC) practices in deployed medical treatment facilities and in the evacuation of the injured back to the United States. Level III facilities (hospitals capable of holding patients >72 hours) in Iraq and Afghanistan and the evacuation system from Iraq to the continental US were reviewed by an expert IC-infectious disease team. All reviewed facilities had established IC programs, but these were staffed by personnel with limited IC experience, often without perceived adequate time dedicated to perform their duties, and without uniform levels of command emphasis or support. Proper hand hygiene between patients was not always ideal. Isolation and cohorting of patients to decrease multidrug-resistant organism colonization and infection varied among facilities. Review of standard operating procedures found variability among institutions and in quality of these documents. Application of US national and theater-specific guidelines and of antimicrobial control measures also varied among facilities. Effective IC practices are often difficult to maintain in modern US hospitals. In the deployed setting, with ever-changing personnel in a less than optimal practice environment, IC is even more challenging. Standardization of practice with emphasis on the basics of IC practice (e.g., hand hygiene and isolation procedures) needs to be emplaced and maintained in the deployed setting.

Investigation of an outbreak of Enterobacter cloacae in a neonatal unit and review of the literature

Enterobacter cloacae has emerged as an important pathogen in neonatal units, with several outbreaks of infection being reported. The aim of this study was to investigate an outbreak of sepsis due to E. cloacae in a neonatal unit and to review the literature. A retrospective cohort study was conducted in which cases were compared with all newborns hospitalised for more than 48h in the neonatal intensive care unit (NICU). Cohorting of infected patients and work reorganisation were implemented. Pulsed-field gel electrophoresis was performed. The retrospective cohort included the six cases and 13 control patients that had been in the NICU during April 2006. Univariate analysis showed that the use of dobutamine was significantly associated with infection (P=0.036) and that enteral feeding was a protective factor (P=0.02). Multivariate analysis did not find any independent risk factor. Bed occupancy rate in March 2006 was 109.6%, indicating overcrowding. PFGE identified indistinguishable patterns among isolates from all six newborns. PubMed and OVID was search from 1 January 1983 to 15 January 2008 for papers including the terms 'E. cloacae', 'outbreaks', 'clusters' in combination with 'neonate', 'newborn', and 'infant'. We found 26 reports of outbreaks due to E. cloacae in neonate patients: sixteen (52%) were bloodstream infection outbreaks, of which two (12.5%) were related to multiple-dose medications. The source for our outbreak was not identified. Reinforcement of hygiene practices, restrictions on new admissions and the establishment of single-dose medications helped to control the outbreak.

The role of patient isolation and compliance with isolation practices in the control of nosocomial MRSA in acute care

Background Nosocomial infection remains the most common complication of hospitalisation. Despite infection control efforts, nosocomial methicillin resistant Staphylococcus aureus (MRSA) transmission continues to rise. Various isolation practices are used to minimise MRSA transmission in acute care. However, the effectiveness of these practices has seldom been evaluated. Objectives This review sought to evaluate the efficacy of isolation practices in minimising MRSA transmission in the acute hospital setting and explore staff, visitor and patient compliance with isolation practices. This review updates a review published in 2002. Search strategy A systematic search for relevant published or unpublished English language literature was undertaken using electronic databases, the reference lists of retrieved papers and the Internet. This extended the search published in the original review. Databases searched included: Medline, CINAHL, EMBASE, Cochrane Library and Joanna Briggs Institute Evidence Library. Selection criteria All English language research reports published between 1990 and August 2005 that focused on the role of isolation practices on the nosocomial transmission of MRSA in adult, paediatric or neonatal acute care settings were eligible for inclusion in the review. Studies that evaluated multiple infection control strategies or control of MRSA outbreaks were excluded. The main outcome of interest was the incidence of new cases of MRSA. The secondary outcome was staff, visitor and patient compliance with the isolation practices. Data collection and analysis Two reviewers assessed each paper against the inclusion criteria and a validated quality scale. Data extraction was undertaken using a tool designed specifically for this review. Statistical comparisons of findings were not possible, so findings are presented in a narrative form. Results Seven studies met the inclusion criteria. Given the small number of included studies and variable methodological quality, care must be taken when interpreting the review findings. There is some evidence that cessation of single room isolation and cohorting of MRSA patients does not increase nosocomial MRSA transmission when hand-washing compliance and standard precautions are maintained. Indeed, there is some evidence that reduced MRSA transmission can be achieved by improving compliance with contact precautions alone. The low level of hand hygiene compliance reported in the literature suggests that staff compliance with isolation practices is a significant factor in evaluating any infection-controlled intervention in the clinical setting. While staff compliance data are conflicting, regular audit and feedback of performance may improve compliance. Implications for clinical practice The heterogeneous nature of the topic and methodological weaknesses of included studies impairs the ability to aggregate data and develop specific practice recommendations. While this review presents evidence to suggest that ceasing single room or cohort isolation does not lead to increased MRSA transmission, these studies maintained high levels of hand hygiene or standard precautions. Additionally, the role of extraneous factors, such as environmental reservoirs, specific MRSA strains and patient mix, is unclear. None of the included studies measured financial, social or psychological factors associated with isolation practices. There is an urgent need for well-designed research with significant sample sizes to develop an evidence base upon which to underpin future clinical practice.

The role of patient isolation and compliance with isolation practices in the control of nosocomial MRSA in acute care

Background Nosocomial infection remains the most common complication of hospitalisation. Despite infection control efforts, nosocomial methicillin resistant Staphylococcus aureus (MRSA) transmission continues to rise. Various isolation practices are used to minimise MRSA transmission in acute care. However, the effectiveness of these practices has seldom been evaluated. Objectives This review sought to evaluate the efficacy of isolation practices in minimising MRSA transmission in the acute hospital setting and explore staff, visitor and patient compliance with isolation practices. This review updates a review published in 2002. Search strategy A systematic search for relevant published or unpublished English language literature was undertaken using electronic databases, the reference lists of retrieved papers and the Internet. This extended the search published in the original review. Databases searched included: Medline, CINAHL, EMBASE, Cochrane Library and Joanna Briggs Institute Evidence Library. Selection criteria All English language research reports published between 1990 and August 2005 that focused on the role of isolation practices on the nosocomial transmission of MRSA in adult, paediatric or neonatal acute care settings were eligible for inclusion in the review. Studies that evaluated multiple infection control strategies or control of MRSA outbreaks were excluded. The main outcome of interest was the incidence of new cases of MRSA. The secondary outcome was staff, visitor and patient compliance with the isolation practices. Data collection and analysis Two reviewers assessed each paper against the inclusion criteria and a validated quality scale. Data extraction was undertaken using a tool designed specifically for this review. Statistical comparisons of findings were not possible, so findings are presented in a narrative form. Results Seven studies met the inclusion criteria. Given the small number of included studies and variable methodological quality, care must be taken when interpreting the review findings. There is some evidence that cessation of single room isolation and cohorting of MRSA patients does not increase nosocomial MRSA transmission when hand-washing compliance and standard precautions are maintained. Indeed, there is some evidence that reduced MRSA transmission can be achieved by improving compliance with contact precautions alone. The low level of hand hygiene compliance reported in the literature suggests that staff compliance with isolation practices is a significant factor in evaluating any infection-controlled intervention in the clinical setting. While staff compliance data are conflicting, regular audit and feedback of performance may improve compliance. Implications for clinical practice The heterogeneous nature of the topic and methodological weaknesses of included studies impairs the ability to aggregate data and develop specific practice recommendations. While this review presents evidence to suggest that ceasing single room or cohort isolation does not lead to increased MRSA transmission, these studies maintained high levels of hand hygiene or standard precautions. Additionally, the role of extraneous factors, such as environmental reservoirs, specific MRSA strains and patient mix, is unclear. None of the included studies measured financial, social or psychological factors associated with isolation practices. There is an urgent need for well-designed research with significant sample sizes to develop an evidence base upon which to underpin future clinical practice.

Strategies for prevention of RSV nosocomial infection

To review the literature on respiratory syncytial virus (RSV) as a cause of nosocomial infections (NI) on neonatal intensive care units (NICUs) and pediatric wards, and the effectiveness of various containment strategies. We conducted a literature review to define characteristics of RSV NI, and to evaluate the relative effectiveness of various infection containment programs, including the use of palivizumab on the reported incidence of RSV NI on NICUs and pediatric wards. Highly variable rates of RSV NI have not significantly changed since RSV was first identified. The evaluation of the effectiveness of containment strategies has relied on before/after study designs. Focus on rapid patient diagnosis, compliance of acceptable handwashing techniques and cohorting of patients and staff appears to form the backbone of most prevention and containment programs. When these or other measures have failed, the administration of palivizumab has been useful in halting the spread of RSV NI in children. RSV NI continues to be prevalent in the NICU despite adoption of infection control programs. Preventive measures should be employed to lower the risk of RSV NI and, if identified, appropriate containment strategies should be rapidly implemented.

Ventilator Associated Pneumonia in a Military Deployed Setting: The Impact of an Aggressive Infection Control Program

Since the onset of military operations in Iraq and Afghanistan, there has been a marked increased in multidrug resistant bacterial infections among combat casualties. We describe the rates of ventilator-associated pneumonia (VAP) before and after the implementation of aggressive infection control measures at the Air Force Theater Hospital in Iraq. All patients admitted to the intensive care unit (ICU) were followed prospectively for the development of VAP. Baseline VAP rate was determined in May 2006, and preventive measures were implemented by June 2006. Interventions included hand hygiene, contact barrier precautions, patient and staff cohorting, chlorhexidine oral care, and reducing the duration and spectrum of surgical antimicrobial prophylaxis. Additionally, each ICU tent was closed periodically for cleaning and disinfection. Daily inspections provided ongoing staff education and enforcement of procedures. Monthly VAP rates were calculated and compared for trend. There were 475 ICU admissions from May 2006 through August 2006 for a mean admission rate of 119 per month. The rate of VAP per 1,000 ventilator days was 60.6 in May, 31.6 in June, 21.3 in July, and 11.1 in August (p = 0.029). Targeted surveillance in November and December revealed VAP rates of 11.6 and 9.7, respectively. Notably, the most common bacteria, Acinetobacter, had improved antimicrobial susceptibilities after the interventions. Implementation of aggressive infection control procedures in a combat military hospital was associated with a significant decrease in the rate of VAP. Despite the numerous challenges in theater, infection control can have measurable and sustainable impact in a combat theater hospital.

The role of patient isolation and compliance with isolation practices in the control of nosocomial MRSA in acute care

Background Nosocomial infection remains the most common complication of hospitalisation. Despite infection control efforts, nosocomial methicillin resistant Staphylococcus aureus (MRSA) transmission continues to rise. Various isolation practices are used to minimise MRSA transmission in acute care. However, the effectiveness of these practices has seldom been evaluated. Objectives This review sought to evaluate the efficacy of isolation practices in minimising MRSA transmission in the acute hospital setting and explore staff, visitor and patient compliance with isolation practices. This review updates a review published in 2002. Search strategy A systematic search for relevant published or unpublished English language literature was undertaken using electronic databases, the reference lists of retrieved papers and the Internet. This extended the search published in the original review. Databases searched included: Medline, CINAHL, EMBASE, Cochrane Library and Joanna Briggs Institute Evidence Library. Selection criteria All English language research reports published between 1990 and August 2005 that focused on the role of isolation practices on the nosocomial transmission of MRSA in adult, paediatric or neonatal acute care settings were eligible for inclusion in the review. Studies that evaluated multiple infection control strategies or control of MRSA outbreaks were excluded. The main outcome of interest was the incidence of new cases of MRSA. The secondary outcome was staff, visitor and patient compliance with the isolation practices. Data collection and analysis Two reviewers assessed each paper against the inclusion criteria and a validated quality scale. Data extraction was undertaken using a tool designed specifically for this review. Statistical comparisons of findings were not possible, so findings are presented in a narrative form. Results Seven studies met the inclusion criteria. Given the small number of included studies and variable methodological quality, care must be taken when interpreting the review findings. There is some evidence that cessation of single room isolation and cohorting of MRSA patients does not increase nosocomial MRSA transmission when hand-washing compliance and standard precautions are maintained. Indeed, there is some evidence that reduced MRSA transmission can be achieved by improving compliance with contact precautions alone. The low level of hand hygiene compliance reported in the literature suggests that staff compliance with isolation practices is a significant factor in evaluating any infection-controlled intervention in the clinical setting. While staff compliance data are conflicting, regular audit and feedback of performance may improve compliance. Implications for clinical practice The heterogeneous nature of the topic and methodological weaknesses of included studies impairs the ability to aggregate data and develop specific practice recommendations. While this review presents evidence to suggest that ceasing single room or cohort isolation does not lead to increased MRSA transmission, these studies maintained high levels of hand hygiene or standard precautions. Additionally, the role of extraneous factors, such as environmental reservoirs, specific MRSA strains and patient mix, is unclear. None of the included studies measured financial, social or psychological factors associated with isolation practices. There is an urgent need for well-designed research with significant sample sizes to develop an evidence base upon which to underpin future clinical practice.

The role of patient isolation and compliance with isolation practices in the control of nosocomial MRSA in acute care.

Nosocomial infection remains the most common complication of hospitalisation. Despite infection control efforts, nosocomial methicillin resistant Staphylococcus aureus (MRSA) transmission continues to rise. Various isolation practices are used to minimise MRSA transmission in acute care. However, the effectiveness of these practices has seldom been evaluated. This review sought to evaluate the efficacy of isolation practices in minimising MRSA transmission in the acute hospital setting and explore staff, visitor and patient compliance with isolation practices. This review updates a review published in 2002. A systematic search for relevant published or unpublished English language literature was undertaken using electronic databases, the reference lists of retrieved papers and the Internet. This extended the search published in the original review. Databases searched included: Medline, CINAHL, EMBASE, Cochrane Library and Joanna Briggs Institute Evidence Library. All English language research reports published between 1990 and August 2005 that focused on the role of isolation practices on the nosocomial transmission of MRSA in adult, paediatric or neonatal acute care settings were eligible for inclusion in the review. Studies that evaluated multiple infection control strategies or control of MRSA outbreaks were excluded. The main outcome of interest was the incidence of new cases of MRSA. The secondary outcome was staff, visitor and patient compliance with the isolation practices. Two reviewers assessed each paper against the inclusion criteria and a validated quality scale. Data extraction was undertaken using a tool designed specifically for this review. Statistical comparisons of findings were not possible, so findings are presented in a narrative form. Seven studies met the inclusion criteria. Given the small number of included studies and variable methodological quality, care must be taken when interpreting the review findings. There is some evidence that cessation of single room isolation and cohorting of MRSA patients does not increase nosocomial MRSA transmission when hand-washing compliance and standard precautions are maintained. Indeed, there is some evidence that reduced MRSA transmission can be achieved by improving compliance with contact precautions alone.The low level of hand hygiene compliance reported in the literature suggests that staff compliance with isolation practices is a significant factor in evaluating any infection-controlled intervention in the clinical setting. While staff compliance data are conflicting, regular audit and feedback of performance may improve compliance. The heterogeneous nature of the topic and methodological weaknesses of included studies impairs the ability to aggregate data and develop specific practice recommendations.While this review presents evidence to suggest that ceasing single room or cohort isolation does not lead to increased MRSA transmission, these studies maintained high levels of hand hygiene or standard precautions. Additionally, the role of extraneous factors, such as environmental reservoirs, specific MRSA strains and patient mix, is unclear. None of the included studies measured financial, social or psychological factors associated with isolation practices. There is an urgent need for well-designed research with significant sample sizes to develop an evidence base upon which to underpin future clinical practice.

Intensified Strategies to Control Vancomycin-Resistant Enterococci in Immunocompromised Patients

Increasing colonization and infection with vancomycin-resistant enterococci (VRE) in immunocompromised patients are associated with increased mortality. Despite contact precautions for VRE control, rapid limitation of its spread is often impossible. We report on a VRE outbreak in a hematologic/oncologic unit including 33 patients. Although 28 of the patients had only VRE colonization, VRE-related infection was probable in 4 patients, and VRE infection of the bloodstream occurred in 1 case. Two patients were identified by VRE screening on admission, 20 were identified by weekly routine VRE screening, and 6 were identified from specimens taken to clarify infections (eg, urine, bronchoalveolar lavage). Five individuals acquired VRE colonization as inpatients (contact patients). Multiple-locus variable-number tandem repeat analysis (MLVA) proved that the outbreak was caused by VanA gene-positive Enterococcus faecium belonging to MLVA genogroup C1(MLVA types 1, 7, 12). The outbreak strains exhibited the potential virulence factor esp(enterococcus surface protein). The outbreak was terminated within 2 months by intensified infection-control measures, including quarantine and the cohorting of patients who tested positive for VRE; however, VRE spread recurred after the measures were discontinued but was again limited by resuming the measures. We conclude that intensive infection-control strategies enable the timely termination of VRE outbreaks, even those involving VRE strains with high epidemic potential on "high-risk wards" (eg, hematologic/oncologic units). Premature discontinuation of infection-control measures may cause recurrence of the VRE spread.

A Case of Healthcare-Associated, Multidrug-Resistant Tuberculosis in Austria: Reconsidering the Value of Cohorting of Patients with Culture-Positive Tuberculosis

Cohorting of patients with culture-positive tuberculosis is still widely practiced in Austria, a country where approximately 1% of Mycobacterium tuberculosis isolates are multidrug resistant. Cohorting of patients with tuberculosis prior to determination of drug susceptibility is unacceptable because M. tuberculosis superinfection can occur.

A stochastic mathematical model of methicillin resistant Staphylococcus aureus transmission in an intensive care unit: Predicting the impact of interventions

Objectives: To estimate the transmission rate of MRSA in an intensive care unit (ICU) in an 800 bed Australian teaching hospital and predict the impact of infection control interventions. Methods: A mathematical model was developed which consisted of four compartments: colonised and uncolonised patients and contaminated and uncontaminated health-care workers (HCWs). Patient movements, MRSA acquisition and daily prevalence data were collected from an ICU over 939 days. Hand hygiene compliance and the probability of MRSA transmission from patient to HCW per discordant contact were measured during the study. Attack rate and reproduction ratio were estimated using Bayesian methods. The impact of a number of interventions on attack rate was estimated using both stochastic and deterministic versions of the model. Results: The mean number of secondary cases arising from the ICU admission of colonised patients, also called the ward reproduction ratio, R w , was estimated to be 0.50 (95% CI 0.39–0.62). The attack rate was one MRSA transmission per 160 (95% CI 130–210) uncolonised-patient days. Results were not sensitive to uncertainty in measured model parameters (hand hygiene rate and transmission probability per contact). Hand hygiene was predicted to be the most effective intervention. Decolonisation was predicted to be relatively ineffective. Increasing HCW numbers was predicted to increase MRSA transmission, in the absence of patient cohorting. The predictions of the stochastic model differed from those of the deterministic model, with lower levels of colonisation predicted by the stochastic model. Conclusions: The number of secondary cases of MRSA colonisation within the ICU in this study was below unity. Transmission of MRSA was sustained through admission of colonised patients. Stochastic model simulations give more realistic predictions in hospital ward settings than deterministic models. Increasing staff does not necessarily lead to reduced transmission of nosocomial pathogens.

Rapid control of norovirus gastroenteritis outbreak in an acute paediatric ward

To provide a practical action plan for effective infection control of norovirus outbreak in acute paediatric wards. We report the infection control measures that were implemented to terminate and to prevent nosocomial spread of norovirus gastroenteritis in an open-designed paediatric ward. Nine children, one visitor, and one medical student were affected in a norovirus gastroenteritis outbreak in an acute paediatric ward. Vomiting was the main presenting symptom. The outbreak was rapidly terminated three days after implementation of stringent infection control measures and there was no second wave of attack. These measures included strict contact precautions, prompt isolation and cohorting of symptomatic patients, vigorous environmental cleansing with concentrated disinfectant (hypochlorite solution 1000 ppm), meticulous handling of waste products, and efficient contact tracing of exposed patients, family members, and medical students. Prompt implementation of stringent infection control measures and contact tracing can rapidly terminate the norovirus outbreak and prevent a second wave of infection. Children with unexplained vomiting and those with contact history of gastroenteritis should be properly triaged, isolated, and investigated for possible infective causes, including norovirus-induced gastroenteritis.

Rapid control of norovirus gastroenteritis outbreak in an acute paediatric ward

Abstract Aim: To provide a practical action plan for effective infection control of norovirus outbreak in acute paediatric wards. Methods: We report the infection control measures that were implemented to terminate and to prevent nosocomial spread of norovirus gastroenteritis in an open‐designed paediatric ward. Results: Nine children, one visitor, and one medical student were affected in a norovirus gastroenteritis outbreak in an acute paediatric ward. Vomiting was the main presenting symptom. The outbreak was rapidly terminated three days after implementation of stringent infection control measures and there was no second wave of attack. These measures included strict contact precautions, prompt isolation and cohorting of symptomatic patients, vigorous environmental cleansing with concentrated disinfectant (hypochlorite solution 1000 ppm), meticulous handling of waste products, and efficient contact tracing of exposed patients, family members, and medical students. Conclusion: Prompt implementation of stringent infection control measures and contact tracing can rapidly terminate the norovirus outbreak and prevent a second wave of infection. Children with unexplained vomiting and those with contact history of gastroenteritis should be properly triaged, isolated, and investigated for possible infective causes, including norovirus‐induced gastroenteritis.

Evaluation of rapid screening and pre-emptive contact isolation for detecting and controlling methicillin-resistant Staphylococcus aureus in critical care: an interventional cohort study

IntroductionRapid diagnostic tests may allow early identification of previously unknown methicillin-resistant Staphylococcus aureus (MRSA) carriers at intensive care unit (ICU) admission. The aim of this study was twofold: first, to assess whether a new molecular MRSA screening test can substantially decrease the time between ICU admission and identification of MRSA carriers; and, second, to examine the combined effect of rapid testing and pre-emptive contact isolation on MRSA infections.MethodSince November 2003, patients admitted for longer than 24 hours to two adult ICUs were screened systematically on admission using quick, multiplex immunocapture-coupled PCR (qMRSA). Median time intervals from admission to notification of test results were calculated for a five-month intervention phase (November 2003–March 2004) and compared with a historical control period (April 2003–October 2003) by nonparametric tests. ICU-acquired MRSA infection rates were determined for an extended surveillance period (January 2003 through August 2005) and analyzed by Poisson regression methods.ResultsDuring the intervention phase, 97% (450/462) of patients admitted to the surgical ICU and 80% (470/591) of patients admitted to the medical ICU were screened. On-admission screening identified the prevalence of MRSA to be 6.7% (71/1053). Without admission screening, 55 previously unknown MRSA carriers would have been missed in both ICUs. Median time from ICU admission to notification of test results decreased from 87 to 21 hours in the surgical ICU (P < 0.001) and from 106 to 23 hours in the medical ICU (P < 0.001). In the surgical ICU, 1,227 pre-emptive isolation days for 245 MRSA-negative patients were saved by using the qMRSA test. After adjusting for colonization pressure, the systematic on-admission screening and pre-emptive isolation policy was associated with a reduction in medical ICU acquired MRSA infections (relative risk 0.3, 95% confidence interval 0.1–0.7) but had no effect in the surgical ICU (relative risk 1.0, 95% confidence interval 0.6–1.7).ConclusionThe qMRSA test decreased median time to notification from four days to one day and helped to identify previously unknown MRSA carriers rapidly. A strategy linking the rapid screening test to pre-emptive isolation and cohorting of MRSA patients substantially reduced MRSA cross-infections in the medical but not in the surgical ICU.

Control of a methicillin-resistant Staphylococcus aureus (MRSA) cluster in critical care by reinforcing hand hygiene and standard precautions

ISSUE: The risk of healthcare-associated MRSA colonization and/or infection is considered to be greater for the patient in the critical care environment. Transmission of MRSA in a hospital setting usually occurs by indirect contact via the hands of healthcare workers. To minimize transmission, contact precautions (CP) have been recommended and used by many facilities. Standard precautions (SP) are used for patients with MRSA at this medical center. From April–July 2002, 22 patients in intensive care unit (ICU) and/or coronary care unit (CCU) and cardiovascular intensive care unit (CVICU) became colonized or infected with MRSA. DNA testing revealed that two clones were operational in the cluster. PROJECT: An infection control services (ICS) investigation included observation of patient care practices, interaction with staff to determine factors that might be contributing to MRSA transmission, DNA testing, literature review, audits of waterless alcohol degermer (degermer) use, and consultation with the hospital epidemiologist and the department of health services epidemiologist. No change from established infection control policy was initiated. An interventional partnership program was established between ICS and critical care, respiratory care services, and associated departments. Procedures and practices were observed, analyzed, and reported back to staff along with ICS recommendations to curtail transmission. RESULTS: Staff members (care partners, registered nurses, respiratory therapists, and physicians) were observed for intervals lasting approximately 30 minutes. Lapses in basic infection control practice were observed. The majority of identified problems centered on missed opportunities for the use of the degermer and/or handwashing and breaches in SP. Degermer audits determined that usage was suboptimal. ICS interventions focused on the importance of hand hygiene, emphasizing use of the degermer and reinforcing the principles of SP. Healthcare workers with direct patient contact were discouraged from wearing artificial nails and staff members were reminded to report any skin conditions to employee health services. The cluster terminated with these interventions. LESSONS LEARNED: Adhering to the principles of SP and hand hygiene was sufficient to end a cluster of healthcare-associated MRSA colonization and/or infection. This approach was relatively easy to implement and saved considerable resources by avoiding the institution of: new policies for CP, culturing patients on admission to the unit, culturing of staff, and cohorting of patients or staff.

An Outbreak of Pseudomonas aeruginosa Pneumonia and Bloodstream Infection Associated With Intermittent Otitis Externa in a Healthcare Worker

To investigate an outbreak of Pseudomonas aeruginosa pneumonia and bloodstream infection among four neonates, determine risk factors for infection, and implement preventive strategies. Retrospective case finding; prospective surveillance cultures of patients, personnel, and environmental sites; molecular typing by pulsed-field gel electrophoresis; and a matched case-control study. Neonates in the level-III neonatal intensive care unit of a tertiary-care pediatric institution. Cohorting of patients with positive results for P. aeruginosa, work restrictions for staff with positive results, implementation of an alcohol-based hand product, review of infection control policies and procedures, and closure of the unit until completion of the investigation. Seven (4%) of 190 environmental cultures and 5 (3%) of 178 cultures of individual healthcare workers' hands grew P. aeruginosa. All four outbreak isolates and one previous bloodstream isolate were genotypically identical, as were the P. aeruginosa isolates from the hands and external auditory canal of a healthcare worker with intermittent otitis externa. Four of 5 case-patients versus 5 of 15 matched control-patients had been cared for by this healthcare worker (P = .05). The healthcare worker was treated and no further cases occurred. These findings suggest that a healthcare worker with intermittent otitis externa may have caused this cluster of fatal P. aeruginosa infections, adding the external ear to the list of colonized body sites that may serve as a source of potentially pathogenic organisms.

Burden of Infection in Patients with End-Stage Renal Disease Requiring Long-Term Dialysis

This study examines the spectrum of infections in a selected population of patients requiring long-term dialysis, enlarging the focus beyond infections associated with the dialysis process. Infection data were reviewed from complete archived inpatient and outpatient dialysis records of 433 patients who were treated at a single hospital-based dialysis program and its dialysis satellites over a 9-year period, from 1 January 1992 to 31 December 2000. The study period included 424,700 days of dialysis experience. A total of 2412 episodes of bacterial or fungal infections were treated in 433 patients. The infection rate was 5.7 episodes per 1000 days of dialysis. Patients received 5111 courses of antibiotics over 42,627 days of treatment, which cumulatively accounted for 10% of the total days of the study. Infections associated with hemodialysis vascular access devices comprised 20.5% of the total episodes. Infections below the knee (19.3% of infection episodes), pneumonia (13%), and other skin and soft-tissue infections (9%) were also important types and sources of infection, accounting for >42% of the total episodes. Eighty-two percent of the infections (1971 episodes) were acquired in the community. Of these, 868 (44%) required hospitalization. An additional 441 episodes were nosocomial. The profile of bacteria isolated from patients with community-acquired infections mirrored that of bacteria recovered from patients with nosocomial infections. Patients with end-stage renal disease have an enormous burden of infection. The majority of the infections are unrelated to dialysis. Frequent and long-term antibiotic use and cohorting of patients in the dialysis unit have altered the microbiological flora of such individuals, with clinical and epidemiological implications.

Community-acquired respiratory viruses

Community-acquired respiratory viruses

Patient Cohorting and Infection Control

Patients with cystic fibrosis (CF) have an abnormal propensity for recurrent and chronic infections of the lower respiratory tract (LRT), and the most common cause of a shortened lifespan is chronic infection with Pseudomonas aeruginosa. A few other gram-negative organisms, primarily Burkholderia cepacia complex have, however, emerged as serious pathogens capable of establishing chronic LRT infection. Details of these and other CF pathogens can be found in the article by Dr. John LiPuma, Burkholderia and Emerging Pathogens in Cystic Fibrosis, in this issue. Chronically infected patients constitute a major microbial reservoir from which noninfected patients can be infected with both P. aeruginosa and B. cepacia complex by direct patient-to-patient transmission, and possibly also by exposure to contaminated environments. Other more rare pathogens such as Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and nontuberculous mycobacteria (NTM) appear less capable of causing patient-to-patient transmission. Both the physical proximity and the duration of exposure of noninfected patients to patients chronically infected with P. aeruginosa and B. cepacia complex are important determinants of the risk of cross-infection. Cohorting of patients according to presence or absence of specific pathogens coupled with conventional hygienic precautions can, however, lead to a decrease in incidence and prevalence of chronic infections with these two species, wherefore patient cohorting is now an integral component of infection control in patients with CF.