Keeping health care linens clean: Underrecognized hazards and critical control points to avoid contamination of laundered health care textiles

Outbreaks of health care-associated infections, particularly invasive mold infections, have been linked to environmental contamination of laundered health care textiles. Contamination may occur at the laundry or health care facility. This report highlights underrecognized hazards, control points, and actions that infection preventionists can take to help decrease the potential for patient exposure to contaminated health care textiles. Infection preventionists can use the checklists included in this report to assess laundry and health care facility management of laundered health care textiles.

Clinical Laboratory Biosafety Gaps: Lessons Learned from Past Outbreaks Reveal a Path to a Safer Future

Patient care and public health require timely, reliable laboratory testing. However, clinical laboratory professionals rarely know whether patient specimens contain infectious agents, making ensuring biosafety while performing testing procedures challenging. The importance of biosafety in clinical laboratories was highlighted during the 2014 Ebola outbreak, where concerns about biosafety resulted in delayed diagnoses and contributed to patient deaths. This review is a collaboration between subject matter experts from large and small laboratories and the federal government to evaluate the capability of clinical laboratories to manage biosafety risks and safely test patient specimens. We discuss the complexity of clinical laboratories, including anatomic pathology, and describe how applying current biosafety guidance may be difficult as these guidelines, largely based on practices in research laboratories, do not always correspond to the unique clinical laboratory environments and their specialized equipment and processes. We retrospectively describe the biosafety gaps and opportunities for improvement in the areas of risk assessment and management; automated and manual laboratory disciplines; specimen collection, processing, and storage; test utilization; equipment and instrumentation safety; disinfection practices; personal protective equipment; waste management; laboratory personnel training and competency assessment; accreditation processes; and ethical guidance. Also addressed are the unique biosafety challenges successfully handled by a Texas community hospital clinical laboratory that performed testing for patients with Ebola without a formal biocontainment unit. The gaps in knowledge and practices identified in previous and ongoing outbreaks demonstrate the need for collaborative, comprehensive solutions to improve clinical laboratory biosafety and to better combat future emerging infectious disease outbreaks.

The Centers for Disease Control and Prevention Guidance on Flexible Gastrointestinal Endoscopes: Lessons Learned from Outbreaks, Infection Control

Flexible endoscopes require cleaning, high-level disinfection, and sterilization between each patient use to reduce risk of transmitting pathogens. Public health investigations have identified concerns, including endoscope damage, mishandling, and reprocessing deficiencies, placing patients at risk for transmission of bacterial, viral, and other pathogens. Findings from outbreak investigations and other studies have led to innovations in endoscope design, use, and reprocessing, yet infection risks related to contaminated or damaged endoscopes remain. Strict adherence to infection control guidelines and manufacturer instructions for use, utilization of supplemental guidance, and training and oversight of reprocessing personnel, reduce risk of pathogen transmission by flexible endoscopes.

Outbreaks Associated with Treated Recreational Water - United States, 2000-2014

Outbreaks associated with exposure to treated recreational water can be caused by pathogens or chemicals in venues such as pools, hot tubs/spas, and interactive water play venues (i.e., water playgrounds). During 2000-2014, public health officials from 46 states and Puerto Rico reported 493 outbreaks associated with treated recreational water. These outbreaks resulted in at least 27,219 cases and eight deaths. Among the 363 outbreaks with a confirmed infectious etiology, 212 (58%) were caused by Cryptosporidium (which causes predominantly gastrointestinal illness), 57 (16%) by Legionella (which causes Legionnaires' disease, a severe pneumonia, and Pontiac fever, a milder illness with flu-like symptoms), and 47 (13%) by Pseudomonas (which causes folliculitis ["hot tub rash"] and otitis externa ["swimmers' ear"]). Investigations of the 363 outbreaks identified 24,453 cases; 21,766 (89%) were caused by Cryptosporidium, 920 (4%) by Pseudomonas, and 624 (3%) by Legionella. At least six of the eight reported deaths occurred in persons affected by outbreaks caused by Legionella. Hotels were the leading setting, associated with 157 (32%) of the 493 outbreaks. Overall, the outbreaks had a bimodal temporal distribution: 275 (56%) outbreaks started during June-August and 46 (9%) in March. Assessment of trends in the annual counts of outbreaks caused by Cryptosporidium, Legionella, or Pseudomonas indicate mixed progress in preventing transmission. Pathogens able to evade chlorine inactivation have become leading outbreak etiologies. The consequent outbreak and case counts and mortality underscore the utility of CDC's Model Aquatic Health Code (https://www.cdc.gov/mahc) to prevent outbreaks associated with treated recreational water.

Vital Signs: Health Care-Associated Legionnaires' Disease Surveillance Data From 20 States and a Large Metropolitan Area-United States, 2015

BACKGROUND

Legionnaires' disease, a severe pneumonia, is typically acquired through inhalation of aerosolized water containing Legionella bacteria. Legionella can grow in the complex water systems of buildings, including health care facilities. Effective water management programs could prevent the growth of Legionella in building water systems.

METHODS

Using national surveillance data, Legionnaires' disease cases were characterized from the 21 jurisdictions (20 U.S. states and one large metropolitan area) that reported exposure information for ≥90% of 2015 Legionella infections. An assessment of whether cases were health care-associated was completed; definite health care association was defined as hospitalization or long-term care facility residence for the entire 10 days preceding symptom onset, and possible association was defined as any exposure to a health care facility for a portion of the 10 days preceding symptom onset. All other Legionnaires' disease cases were considered unrelated to health care.

RESULTS

A total of 2,809 confirmed Legionnaires' disease cases were reported from the 21 jurisdictions, including 85 (3%) definite and 468 (17%) possible health care-associated cases. Among the 21 jurisdictions, 16 (76%) reported 1-21 definite health care-associated cases per jurisdiction. Among definite health care-associated cases, the majority (75, 88%) occurred in persons aged ≥60 years, and exposures occurred at 72 facilities (15 hospitals and 57 long-term care facilities). The case fatality rate was 25% for definite and 10% for possible health care-associated Legionnaires' disease.

CONCLUSIONS AND IMPLICATIONS FOR PUBLIC HEALTH PRACTICE

Exposure to Legionella from health care facility water systems can result in Legionnaires' disease. The high case fatality rate of health care-associated Legionnaires' disease highlights the importance of case prevention and response activities, including implementation of effective water management programs and timely case identification.

Vital Signs: Health Care-Associated Legionnaires' Disease Surveillance Data from 20 States and a Large Metropolitan Area - United States, 2015

Background

Legionnaires’ disease, a severe pneumonia, is typically acquired through inhalation of aerosolized water containing Legionella bacteria. Legionella can grow in the complex water systems of buildings, including health care facilities. Effective water management programs could prevent the growth of Legionella in building water systems.

Methods

Using national surveillance data, Legionnaires’ disease cases were characterized from the 21 jurisdictions (20 U.S. states and one large metropolitan area) that reported exposure information for ≥90% of 2015 Legionella infections. An assessment of whether cases were health care–associated was completed; definite health care association was defined as hospitalization or long-term care facility residence for the entire 10 days preceding symptom onset, and possible association was defined as any exposure to a health care facility for a portion of the 10 days preceding symptom onset. All other Legionnaires’ disease cases were considered unrelated to health care.

Results

A total of 2,809 confirmed Legionnaires’ disease cases were reported from the 21 jurisdictions, including 85 (3%) definite and 468 (17%) possible health care–associated cases. Among the 21 jurisdictions, 16 (76%) reported 1–21 definite health care–associated cases per jurisdiction. Among definite health care–associated cases, the majority (75, 88%) occurred in persons aged ≥60 years, and exposures occurred at 72 facilities (15 hospitals and 57 long-term care facilities). The case fatality rate was 25% for definite and 10% for possible health care–associated Legionnaires’ disease.

Conclusions and Implications for Public Health Practice

Exposure to Legionella from health care facility water systems can result in Legionnaires’ disease. The high case fatality rate of health care–associated Legionnaires’ disease highlights the importance of case prevention and response activities, including implementation of effective water management programs and timely case identification.

Early Identification and Prevention of the Spread of Ebola - United States

In response to the 2014-2016 Ebola virus disease (Ebola) epidemic in West Africa, CDC prepared for the potential introduction of Ebola into the United States. The immediate goals were to rapidly identify and isolate any cases of Ebola, prevent transmission, and promote timely treatment of affected patients. CDC's technical expertise and the collaboration of multiple partners in state, local, and municipal public health departments; health care facilities; emergency medical services; and U.S. government agencies were essential to the domestic preparedness and response to the Ebola epidemic and relied on longstanding partnerships. CDC established a comprehensive response that included two new strategies: 1) active monitoring of travelers arriving from countries affected by Ebola and other persons at risk for Ebola and 2) a tiered system of hospital facility preparedness that enabled prioritization of training. CDC rapidly deployed a diagnostic assay for Ebola virus (EBOV) to public health laboratories. Guidance was developed to assist in evaluation of patients possibly infected with EBOV, for appropriate infection control, to support emergency responders, and for handling of infectious waste. CDC rapid response teams were formed to provide assistance within 24 hours to a health care facility managing a patient with Ebola. As a result of the collaborations to rapidly identify, isolate, and manage Ebola patients and the extensive preparations to prevent spread of EBOV, the United States is now better prepared to address the next global infectious disease threat.The activities summarized in this report would not have been possible without collaboration with many U.S. and international partners (http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/partners.html).

Tetrasodium EDTA as a Novel Central Venous Catheter Lock Solution Against Biofilm

Background:

Central venous catheter (CVC)-related bloodstream infections (BSIs) are known to increase rates of morbidity and mortality in both inpatients and outpatients, including hematology-oncology patients and those undergoing hemodialysis or home infusion therapy. Biofilm-associated organisms on the lumens of these catheters have reduced susceptibility to antimicrobial chemotherapy. This study tested the efficacy of tetrasodium EDTA as a catheter lock solution on biofilms of several clinically relevant microorganisms.

Methods:

Biofilms ofStaphylococcus epidermidis, methicillin-resistantS. aureus, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, andCandida albicanswere grown to levels of approximately 1 × 105colony-forming units (CFU)/cm−1on CVC segments in a model system, then subjected to the tetrasodium EDTA lock treatment.

Results:

Comparisons of biofilms before and after exposure to the 40-mg/mL−1tetrasodium EDTA lock for 21 hours showed that the biofilm viable cell counts of all organisms tested were significantly reduced (P< .05) after exposure to the treatment.

Conclusion:

Antimicrobial lock treatment using 40 mg/mL−1of tetrasodium EDTA for at least 21 hours could significantly reduce or potentially eradicate CVC-associated bio-films of clinically relevant microorganisms (Infect Control Hosp Epidemiol2005;26:515-519).

Outbreak of Bloodstream Infection With the Mold Phialemonium Among Patients Receiving Dialysis at a Hemodialysis Unit

Background

Molds are a rare cause of disseminated infection among dialysis patients.

Objective.

We evaluated a cluster of intravascular infections with the mold Phialemonium among patients receiving hemodialysis at the same facility in order to identify possible environmental sources and prevent further infection.

Design.

Environmental assessment and case-control study.

Setting.

A hemodialysis center affiliated with a tertiary care hospital.

Methods.

We reviewed surveillance and clinical microbiology records and performed a blood culture survey for all patients. The following data for case patients were compared with those for control patients: underlying illness, dialysis characteristics, medications, and other possible exposure for 120 days prior to infection. Environmental assessment of water treatment, dialysis facilities, and heating, ventilation, and air-conditioning (HVAC) systems of the current and previous locations of the dialysis center was performed. Samples were cultured for fungus; Phialemonium isolates were confirmed by sequencing of DNA. Investigators observed dialysis access site disinfection technique.

Results.

Four patients were confirmed as case patients, defined as a patient having intravascular infection with Phialemonium species; 3 presented with fungemia, and 1 presented with an intravascular graft infection. All case patients used a fistula or graft for dialysis access, as did 12 (75%) of 16 of control patients (P = .54). Case and control patients did not differ in other dialysis characteristics, medications received, physiologic findings, or demographic factors. Phialemonium species were not recovered from samples of water or dialysis machines, but were recovered from the condensation drip pans under the blowers of the HVAC system that supplied air to the dialysis center. Observational study of 21 patients detected suboptimal contact time with antiseptic agents used to prepare dialysis access sites.

Conclusion.

The report of this outbreak adds to previous published reports of Phialemonium infection occurring in immunocompromised patients who likely acquired infection in the healthcare setting. Recovery of this mold from blood culture should be considered indicative of infection until proven otherwise. Furthermore, an investigation into possible healthcare-related environmental reservoirs should be considered.

Notes from the Field: Probable Mucormycosis Among Adult Solid Organ Transplant Recipients at an Acute Care Hospital - Pennsylvania, 2014-2015

On September 17, 2015, the Pennsylvania Department of Health (PADOH) notified CDC of a cluster of three potentially health care-associated mucormycete infections that occurred among solid organ transplant recipients during a 12-month period at hospital A. On September 18, hospital B reported that it had identified an additional transplant recipient with mucormycosis. Hospitals A and B are part of the same health care system and are connected by a pedestrian bridge. PADOH requested CDC's assistance with an on-site investigation, which started on September 22, to identify possible sources of infection and prevent additional infections.

Epidemiology and Ecology of Opportunistic Premise Plumbing Pathogens: Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa

BACKGROUND

Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa are opportunistic premise plumbing pathogens (OPPPs) that persist and grow in household plumbing, habitats they share with humans. Infections caused by these OPPPs involve individuals with preexisting risk factors and frequently require hospitalization.

OBJECTIVES

The objectives of this report are to alert professionals of the impact of OPPPs, the fact that 30% of the population may be exposed to OPPPs, and the need to develop means to reduce OPPP exposure. We herein present a review of the epidemiology and ecology of these three bacterial OPPPs, specifically to identify common and unique features.

METHODS

A Water Research Foundation-sponsored workshop gathered experts from across the United States to review the characteristics of OPPPs, identify problems, and develop a list of research priorities to address critical knowledge gaps with respect to increasing OPPP-associated disease.

DISCUSSION

OPPPs share the common characteristics of disinfectant resistance and growth in biofilms in water distribution systems or premise plumbing. Thus, they share a number of habitats with humans (e.g., showers) that can lead to exposure and infection. The frequency of OPPP-infected individuals is rising and will likely continue to rise as the number of at-risk individuals is increasing. Improved reporting of OPPP disease and increased understanding of the genetic, physiologic, and structural characteristics governing the persistence and growth of OPPPs in drinking water distribution systems and premise plumbing is needed.

CONCLUSIONS

Because broadly effective community-level engineering interventions for the control of OPPPs have yet to be identified, and because the number of at-risk individuals will continue to rise, it is likely that OPPP-related infections will continue to increase. However, it is possible that individuals can take measures (e.g., raise hot water heater temperatures and filter water) to reduce home exposures.

Hepatitis C Virus Transmission in Hemodialysis Units Importance of Infection Control Practices and Aseptic Technique

We investigated 4 hepatitis C virus (HCV) infection outbreaks at hemodialysis units to identify practices associated with transmission. Apparent failures to follow recommended infection control precautions resulted in patient-to-patient HCV transmission, through cross-contamination of the environment or intravenous medication vials. Fastidious attention to aseptic technique and infection control precautions are essential to prevent HCV transmission.

Contaminated Product Water as the Source ofPhialemonium curvatumBloodstream Infection among Patients Undergoing Hemodialysis

Objective.

We investigated a cluster of cases of bloodstream infection (BSI) due to the moldPhialemoniumat a hemodialysis center in Illinois and conducted a cohort study to identify risk factors.

Design.

Environmental assessment and cohort study.

Setting.

A hemodialysis center in a tertiary care hospital.

Methods.

A case patient was defined as a person who underwent dialysis at the center and had a blood sample that tested positive forPhialemonium curvatumon culture. We reviewed microbiology and medical records and tested water, surface, and dialysate samples by culture. Molds isolated from environmental and clinical specimens were identified by their morphological features and confirmed by sequencing DNA.

Results.

We identified 2 case patients with BSI due toP. curvatum. Both became febrile and hypotensive while undergoing dialysis on the same machine at the same treatment station, although on different days. Dialysis machines were equipped with waste handling option ports that are used to discard dialyzer priming fluid. We isolatedP. curvatumfrom the product water (ie, water used for dialysis purposes) at 2 of 19 treatment stations, one of which was the implicated station.

Conclusion.

The source ofP. curvatumwas likely the water distribution system. To our knowledge, this is the first report of patients acquiring a mold BSI from contaminated product water. The route of exposure in these cases of BSI due toP. curvatummay be related to the malfunction and improper maintenance of the waste handling option ports. Waste handling option ports have been previously implicated as the source of bacterial BSI due to the backflow of waste fluid into a patient's blood line. No additional cases of infection were noted after remediation of the water distribution system and after discontinuing use of waste handling option ports at the facility.

Hemodialysis and water quality

Over 383,900 individuals in the U.S. undergo maintenance hemodialysis that exposes them to water, primarily in the form of dialysate. The quality of water and associated dialysis solutions have been implicated in adverse patient outcomes and is therefore critical. The Association for the Advancement of Medical Instrumentation has published both standards and recommended practices that address both water and the dialyzing solutions. Some of these recommendations have been adopted into Federal Regulations by the Centers for Medicare and Medicaid Services as part of the Conditions for Coverage, which includes limits on specific contaminants within water used for dialysis, dialysate, and substitution fluids. Chemical, bacterial, and endotoxin contaminants are health threats to dialysis patients, as shown by the continued episodic nature of outbreaks since the 1960s causing at least 592 cases and 16 deaths in the U.S. The importance of the dialysis water distribution system, current standards and recommendations, acceptable monitoring methods, a review of chemical, bacterial, and endotoxin outbreaks, and infection control programs are discussed.

Outbreak of hepatitis C virus infections at an outpatient hemodialysis facility: the importance of infection control competencies

In the United States, the prevalence of hepatitis C virus infection among patients treated in hemodialysis facilities is five times higher than among the general population. This study investigated eight new hepatitis C virus infections among patients treated at an outpatient hemodialysis facility. Epidemiologic investigation and viral sequencing demonstrated that transmission likely occurred between patients typically treated during the same or consecutive shifts at the same or a nearby station. Several infection control breaches were observed including lapses involving the preparation, handling, and administration of parenteral medications. Improved infection control education and training for all hemodialysis facility staff is an important component of assuring adherence to appropriate procedures and preventing future outbreaks.

Storage Effects on Sample Integrity of Environmental Surface Sampling Specimens with Bacillus anthracis Spores

The effect of packaging, shipping temperatures and storage times on recovery of Bacillus anthracis. Sterne spores from swabs was investigated. Macrofoam swabs were pre-moistened, inoculated with Bacillus anthracis spores, and packaged in primary containment or secondary containment before storage at -15°C, 5°C, 21°C, or 35°C for 0-7 days. Swabs were processed according to validated Centers for Disease Control/Laboratory Response Network culture protocols, and the percent recovery relative to a reference sample (T₀) was determined for each variable. No differences were observed in recovery between swabs held at -15° and 5°C, (p ≥ 0.23). These two temperatures provided significantly better recovery than swabs held at 21°C or 35°C (all 7 days pooled, p ≤ 0.04). The percent recovery at 5°C was not significantly different if processed on days 1, 2 or 4, but was significantly lower on day 7 (day 2 vs. 7, 5°C, 10², p=0.03). Secondary containment provided significantly better percent recovery than primary containment, regardless of storage time (5°C data, p ≤ 0.008). The integrity of environmental swab samples containing Bacillus anthracis spores shipped in secondary containment was maintained when stored at -15°C or 5°C and processed within 4 days to yield the optimum percent recovery of spores.

Plumbing of hospital premises is a reservoir for opportunistically pathogenic microorganisms: a review

Several bacterial species that are natural inhabitants of potable water distribution system biofilms are opportunistic pathogens important to sensitive patients in healthcare facilities. Waterborne healthcare-associated infections (HAI) may occur during the many uses of potable water in the healthcare environment. Prevention of infection is made more challenging by lack of data on infection rate and gaps in understanding of the ecology, virulence, and infectious dose of these opportunistic pathogens. Some healthcare facilities have been successful in reducing infections by following current water safety guidelines. This review describes several infections, and remediation steps that have been implemented to reduce waterborne HAIs.

Vascular access hemorrhages contribute to deaths among hemodialysis patients

In 2007 the Maryland Medical Examiner noted a potential cluster of fatal vascular access hemorrhages among hemodialysis patients, many of whom died outside of a health-care setting. To examine the epidemiology of fatal vascular access hemorrhages, we conducted a retrospective case review in District of Columbia, Maryland, and Virginia from January 2000 to July 2007 and a case-control study. Records from the Medical Examiner and Centers for Medicare and Medicaid Services were reviewed, from which 88 patients were identified as fatal vascular access hemorrhage cases. To assess risk factors, a subset of 20 cases from Maryland was compared to 38 controls randomly selected among hemodialysis patients who died from non-vascular access hemorrhage causes at the same Maryland facilities. Of the 88 confirmed cases, 55% hemorrhaged from arteriovenous grafts, 24% from arteriovenous fistulas, and 21% from central venous catheters. Of 82 case-patients with known location of hemorrhage, 78% occurred at home or in a nursing home. In the case-control analysis, statistically significant risk factors included the presence of an arteriovenous graft, access-related complications within 6 months of death, and hypertension; presence of a central venous catheter was significantly protective. Psychosocial factors and anticoagulant medications were not significant risk factors. Effective strategies to control vascular access hemorrhage in the home and further delineation of warning signs are needed.

Point-of-use membrane filtration and hyperchlorination to prevent patient exposure to rapidly growing mycobacteria in the potable water supply of a skilled nursing facility

BACKGROUND

Healthcare-associated outbreaks and pseudo-outbreaks of rapidly growing mycobacteria (RGM) are frequently associated with contaminated tap water. A pseudo-outbreak of Mycobacterium chelonae-M. abscessus in patients undergoing bronchoscopy was identified by 2 acute care hospitals. RGM was identified in bronchoscopy specimens of 28 patients, 25 of whom resided in the same skilled nursing facility (SNF). An investigation ruled out bronchoscopy procedures, specimen collection, and scope reprocessing at the hospitals as sources of transmission.

OBJECTIVE

To identify the reservoir for RGM within the SNF and evaluate 2 water system treatments, hyperchlorination and point-of-use (POU) membrane filters, to reduce RGM.

DESIGN

A comparative in situ study of 2 water system treatments to prevent RGM transmission.

SETTING

An SNF specializing in care of patients requiring ventilator support.

METHODS

RGM and heterotrophic plate count (HPC) bacteria were examined in facility water before and after hyperchlorination and in a subsequent 24-week assessment of filtered water by colony enumeration on Middlebrook and R2A media.

RESULTS

Mycobacterium chelonae was consistently isolated from the SNF water supply. Hyperchlorination reduced RGM by 1.5 log(10) initially, but the population returned to original levels within 90 days. Concentration of HPC bacteria also decreased temporarily. RGM were reduced below detection level in filtered water, a 3-log(10) reduction. HPC bacteria were not recovered from newly installed filters, although low quantities were found in water from 2-week-old filters.

CONCLUSION

POU membrane filters may be a feasible prevention measure for healthcare facilities to limit exposure of sensitive individuals to RGM in potable water systems.

Outbreak of Burkholderia cepacia complex among ventilated pediatric patients linked to hospital sinks

We investigated a cluster of Burkholderia cepacia complex colonization in ventilated pediatric patients. Isolates from 15 patients, 2 sink drains, and several ventilator components were found to belong to a single B cenocepacia clone. Hospital tap water used during oral and tracheostomy care was identified as the most likely mechanism for transmission.

Chlorine disinfection of Francisella tularensis

AIMS

To determine the range of free available chlorine (FAC) required for disinfection of the live vaccine strain (LVS) and wild-type strains of Francisella tularensis.

METHODS AND RESULTS

Seven strains of planktonic F. tularensis were exposed to 0·5 mg·l(-1) FAC for two pH values, 7 and 8, at 5 and 25°C. LVS was inactivated 2 to 4 times more quickly than any of the wild-type F. tularensis strains at pH 8 and 5°C.

CONCLUSIONS

Free available chlorine residual concentrations routinely maintained in drinking water distribution systems would require up to two hours to reduce all F. tularensis strains by 4 log10. LVS was inactivated most quickly of the tested strains.

SIGNIFICANCE AND IMPACT OF THE STUDY

This work provides contact time (CT) values that are useful for drinking water risk assessment and also suggests that LVS may not be a good surrogate in disinfection studies.

Epidemiology, surveillance, and prevention of bloodstream infections in hemodialysis patients

Infections cause significant morbidity and mortality in patients undergoing hemodialysis. Bloodstream infections (BSIs) are particularly problematic, accounting for a substantial number of hospitalizations in these patients. Hospitalizations for BSI and other vascular access infections appear to have increased dramatically in hemodialysis patients since 1993. These infections frequently are related to central venous catheter (CVC) use for dialysis access. Regional initiatives that have shown successful decreases in catheter-related BSIs in hospitalized patients have generated interest in replicating this success in outpatient hemodialysis populations. Several interventions have been effective in preventing BSIs in the hemodialysis setting. Avoiding the use of CVCs in favor of access types with lower associated BSI risk is among the most important. When CVCs are used, adherence to evidence-based catheter insertion and maintenance practices can positively influence BSI rates. In addition, facility-level surveillance to detect BSIs and stimulate examination of vascular access use and care practices is essential to a comprehensive approach to prevention. This article describes the current epidemiology of BSIs in hemodialysis patients and effective prevention strategies to decrease the incidence of these devastating infections.

Epidemiology, surveillance, and prevention of hepatitis C virus infections in hemodialysis patients

Hepatitis C virus (HCV) infection is the most common chronic blood-borne infection in the United States; the prevalence in maintenance hemodialysis patients substantially exceeds that in the general population. In hemodialysis patients, HCV infection has been associated with increased occurrence of cirrhosis and hepatocellular carcinoma and increased mortality. Injection drug use and receipt of blood transfusions before 1992 has accounted for most prevalent HCV infections in the United States. However, HCV transmission among patients undergoing hemodialysis has been documented frequently. Outbreak investigations have implicated lapses in infection control practices as the cause of HCV infections. Preventing these infections is an emerging priority for renal care providers, public health agencies, and regulators. Adherence to recommended infection control practices is effective in preventing HCV transmission in hemodialysis facilities. In addition, adoption of routine screening to facilitate the detection of incident HCV infections and hemodialysis-related transmission is an essential component of patient safety and infection prevention efforts. This article describes the current epidemiology of HCV infection in US maintenance hemodialysis patients and prevention practices to decrease its incidence and transmission.

An outbreak of postoperative gram-negative bacterial endophthalmitis associated with contaminated trypan blue ophthalmic solution

We report 6 cases of postsurgical endophthalmitis due to gram-negative bacteria associated with contaminated trypan blue dye from a compounding pharmacy. Unopened trypan blue syringes yielded Pseudomonas aeruginosa and Burkholderia cepacia complex on culture, with pulsed-field gel electrophoresis patterns indistinguishable from patient isolates. Contamination of compounded medications should be considered when investigating outbreaks of postoperative endophthalmitis.

Outbreak of adverse reactions associated with contaminated heparin

BACKGROUND

In January 2008, the Centers for Disease Control and Prevention began a nationwide investigation of severe adverse reactions that were first detected in a single hemodialysis facility. Preliminary findings suggested that heparin was a possible cause of the reactions.

METHODS

Information on clinical manifestations and on exposure was collected for patients who had signs and symptoms that were consistent with an allergic-type reaction after November 1, 2007. Twenty-one dialysis facilities that reported reactions and 23 facilities that reported no reactions were included in a case-control study to identify facility-level risk factors. Unopened heparin vials from facilities that reported reactions were tested for contaminants.

RESULTS

A total of 152 adverse reactions associated with heparin were identified in 113 patients from 13 states from November 19, 2007, through January 31, 2008. The use of heparin manufactured by Baxter Healthcare was the factor most strongly associated with reactions (present in 100.0% of case facilities vs. 4.3% of control facilities, P<0.001). Vials of heparin manufactured by Baxter from facilities that reported reactions contained a contaminant identified as oversulfated chondroitin sulfate (OSCS). Adverse reactions to the OSCS-contaminated heparin were often characterized by hypotension, nausea, and shortness of breath occurring within 30 minutes after administration. Of 130 reactions for which information on the heparin lot was available, 128 (98.5%) occurred in a facility that had OSCS-contaminated heparin on the premises. Of 54 reactions for which the lot number of administered heparin was known, 52 (96.3%) occurred after the administration of OSCS-contaminated heparin.

CONCLUSIONS

Heparin contaminated with OSCS was epidemiologically linked to adverse reactions in this nationwide outbreak. The reported clinical features of many of the cases further support the conclusion that contamination of heparin with OSCS was the cause of the outbreak.

RETRACTED: Structural analysis of biofilm formation by rapidly and slowly growing nontuberculous mycobacteria

This article has been retracted.

Multistate outbreak of toxic anterior segment syndrome, 2005

PURPOSE

To present the findings of an outbreak of toxic anterior segment syndrome (TASS).

SETTING

Six states, 7 ophthalmology surgical centers, United States.

METHODS

Cases were identified through electronic communication networks and via reports to a national TASS referral center. Information on the procedure, details of instrument reprocessing, and products used during cataract surgery were also collected. Medications used during the procedures were tested for endotoxin using a kinetic assay.

RESULTS

The search identified 112 case patients (median age 74 years) from 7 centers from July 19, 2005, through November 28, 2005. Common presenting clinical features included blurred vision (60%), anterior segment inflammation (49%), and cell deposition (56%). Of the patients, 100 (89%) had been exposed to a single brand of balanced salt solution manufactured by Cytosol Laboratories and distributed by Advanced Medical Optics as AMO Endosol. Two patients continued to have residual symptoms. There were no reports of significant breaches in sterile technique or instrument reprocessing. Of 14 balanced salt solution lots, 5 (35%) had levels exceeding the endotoxin limit (0.5 EU/mL). Based on these findings, the balanced salt solution product was withdrawn, resulting in a termination of the outbreak.

CONCLUSIONS

This is the first known report of an outbreak of TASS caused by intrinsic contamination of a product with endotoxin. Ophthalmologists and epidemiologists should be aware of TASS and its common causes. To facilitate investigations of adverse outcomes such as TASS, those performing cataract surgeries should document the type and lot numbers of products used intraoperatively.

A national outbreak of Ralstonia mannitolilytica associated with use of a contaminated oxygen-delivery device among pediatric patients

OBJECTIVES

In August 2005, the Centers for Disease Control and Prevention was notified of a Ralstonia species outbreak among pediatric patients receiving supplemental oxygen therapy with the Vapotherm 2000i (Vapotherm, Inc, Stevensville, MD). The Vapotherm 2000i is a reusable medical device that was used in >900 hospitals in the United States in 2005. Ralstonia are waterborne bacilli that have been implicated in hospital-acquired infections. We initiated an investigation to determine the source of the outbreak and implement infection control and prevention measures.

PATIENTS AND METHODS

We performed a case-control study at 1 hospital and conducted national case findings to obtain clinical and environmental samples for laboratory analysis. Case-patients had health care-acquired Ralstonia colonization or infection. Isolates were compared by using pulsed-field gel electrophoresis. We tested manufacturer-recommended disinfection protocols for the Vapotherm 2000i under simulated-use conditions.

RESULTS

Case-patients at the hospital (n = 5) were more likely to have received Vapotherm therapy than controls. Nationally, Ralstonia mannitolilytica was confirmed in 38 patients (aged 5 days to 7 years); 35 (92%) of the patients were exposed to the Vapotherm 2000i before recovery of the organism. Pulsed-field gel electrophoresis showed related R. mannitolilytica strains from isolates sent from 18 hospitals in 12 states. A Vapotherm machine reprocessed with a protocol proposed by the manufacturer grew Ralstonia spp after 7 days of simulated use. In December 2005, Vapotherm recalled the 2000i.

CONCLUSIONS

Our findings suggest intrinsic contamination of Vapotherm devices with Ralstonia spp. New medical devices may provide therapy equivalent to current devices yet pose novel reprocessing challenges.

Monochloramine inactivation of bacterial select agents

Seven species of bacterial select agents were tested for susceptibility to monochloramine. Under test conditions, the monochloramine routinely maintained in potable water would reduce six of the species by 2 orders of magnitude within 4.2 h. Bacillus anthracis spores would require up to 3.5 days for the same inactivation with monochloramine.

An Outbreak of Burkholderia cepacia Associated With Contamination of Albuterol and Nasal Spray

BACKGROUND

Species within the Burkholderia cepacia complex (Bcc) can contaminate medications and disinfectants and cause severe pneumonia in critically ill patients or persons with cystic fibrosis. In March 2004, we investigated a hospital outbreak of Bcc possibly associated with a contaminated nasal spray.

METHODS

We conducted a matched case-control study, environmental sampling, and observations of infection control practices. Case patients had infection or colonization with Bcc, and control patients had sputum culture not yielding Bcc. Isolates from patients and environmental samples were compared by pulsed-field gel electrophoresis (PFGE).

RESULTS

Bcc was recovered from sputum in 18 patients. Compared with matched control patients (n = 18), case patients were more likely to be receiving mechanical ventilation (p = 0.01), to have been hospitalized > 6 days (p = 0.01), and to have received antimicrobial treatment within 7 days before sputum collection (p = 0.03). Bcc was cultured from opened, but not unopened, multidose albuterol bottles, a nebulizer attached to a ventilator, and opened and unopened nasal spray bottles from contaminated lots. PFGE showed that isolates from albuterol samples and from patients were indistinguishable but unrelated to the nasal spray strain. Observations revealed improper aseptic techniques during respiratory therapy procedures and inadequate nebulizer cleaning.

CONCLUSIONS

Despite a temporal association with use of a contaminated nasal spray, this outbreak was caused by extrinsic contamination of multidose albuterol used for nebulization treatments and lack of adherence to infection control precautions. Implementation and re-enforcement of infection control measures successfully terminated the outbreak.

Evaluation of a macrofoam swab protocol for the recovery of Bacillus anthracis spores from a steel surface

A protocol to recover Bacillus anthracis spores from a steel surface using macrofoam swabs was evaluated for its accuracy, precision, reproducibility, and limit of detection. Macrofoam swabs recovered 31.7 to 49.1% of spores from 10-cm2 steel surfaces with a < or =32.7% coefficient of variation in sampling precision and reproducibility for inocula of > or =38 spores.

Pyrogenic reactions and hemorrhage associated with intrinsic exposure to endotoxin-contaminated intravenous solutions

OBJECTIVE

An epidemiological investigation was conducted to determine risk factors for adverse reactions among patients in hospitals and the possibility of extrinsic or intrinsic contamination of intravenous solutions.

DESIGN

A retrospective cohort study was conducted to identify solutions associated with adverse reactions. Implicated lots were cultured for bacteria, and endotoxin concentrations were measured.

SETTING

Five hospitals in the state of Pernambuco, Brazil, were investigated from February through March 2002.

PATIENTS

Surgical inpatients or outpatients receiving intravenous solutions during the study period.

RESULTS

Of 355 surgical patients or outpatients treated at hospitals, 28 (8%) developed illness within a mean of 2.5 hours after exposure to intravenous solutions implicated in adverse reactions; 5 (17.9%) of the case patients died. Laboratory testing of bottles from the lots of Ringer's lactate solution implicated in deaths demonstrated a high mean endotoxin concentration of 88.3 endotoxin units (EU)/mL (range, 9.7-298.0 EU/mL), compared with the permitted limit in Brazil of <0.5 EU/mL. Testing of metronidazole implicated in adverse reactions at another hospital and produced by the same company that manufactured the lots Ringer's lactate solution also showed high endotoxin concentrations (mean level, 8.3 EU/mL [range, 5.0-58.3 EU/mL]). The outbreak was controlled after a national recall of the implicated brand of intravenous solutions.

CONCLUSIONS

Case patient status was associated with use of Ringer's lactate solution and metronidazole from large bottles, both of which were produced by the same company. High endotoxin concentrations were demonstrated in unopened bottles of implicated products, which is consistent with intrinsic contamination. The high mortality rate may have been compounded by the fact that clinicians administered additional volumes of contaminated 0.9% isotonic sodium chloride solution in response to hypotension or bleeding to some surgical patients. No additional case patients were identified after a national recall of products, inspection, closure of the implicated company's manufacturing facility, and establishment of random quality-control testing of intravenous solutions.

National surveillance of dialysis-associated diseases in the United States, 2002

In December 2002, all U.S. chronic hemodialysis centers were surveyed regarding selected patient care practices and dialysis-associated diseases. The results were compared with similar surveys conducted in previous years. In 2002, 85% of hemodialysis centers were free-standing and 81% operated for profit; the proportion of centers operating for profit has increased each year since 1985. During 1995-2002, the percentage of patients who received dialysis through central catheters increased from 13% to 26%; this trend is worrisome, as infections and antimicrobial use are higher among patients receiving dialysis through catheters. However, during the same period, the percentage of patients receiving dialysis through fistulas increased from 22% to 33%. The percentage of centers reporting one or more patients infected or colonized with vancomycin-resistant enterococci (VRE) increased from 12% in 1995 to 30% in 2002. During 1997-2002, the percentage of patients vaccinated against hepatitis B virus (HBV) infection increased from 47% to 56% and the percentage of staff vaccinated increased from 87% to 90%. In 2002, routine testing for antibody to hepatitis C virus (anti-HCV) was performed on patients at 64% of centers; anti-HCV was found in 7.8% of patients. In 2001, the Centers for Disease Control (CDC) published Recommendations for Preventing Transmission of Infections among Chronic Hemodialysis Patients. Centers were surveyed regarding their awareness of the recommendations and about a variety of infection control practices. In general, the incidence of HBV and HCV was not substantially different for the infection control practices evaluated, including where staff obtain clean supplies for patient treatment, reuse of unused and unopened supplies, and practices for changing external transducer filters/protectors. However, in 2002, the incidence of HBV infection was higher among patients in centers where injectable medications were prepared on a medication cart or medication area located in the treatment area compared to a dedicated medication room. Also, those centers that used a disposable container versus a nondisposable container for priming the dialyzer had a significantly lower incidence of HCV.

Outbreak of catheter-associated Klebsiella oxytoca and Enterobacter cloacae bloodstream infections in an oncology chemotherapy center

BACKGROUND

In March 2004, the Chicago Department of Public Health was notified of a cluster of bloodstream infections with Klebsiella oxytoca and Enterobacter cloacae at a chemotherapy center. Our purpose was to identify the source of the outbreak and prevent further cases.

METHODS

The investigation included 103 oncology patients seen at an outpatient oncology chemotherapy center in Chicago during the 16 days before its closure. The outbreak investigation included case identification, retrospective cohort study, review of medical records, microbiologic testing of blood specimens, environmental cultures, and pulsed-field gel electrophoresis. The main outcome measure was infection with K oxytoca, E cloacae, or both, and the Mantel-Haenszel chi(2) test was used to assess risk of infection in relation to presence of central venous catheter.

RESULTS

Among the 103 patients, risk of infection was associated with the presence of central venous catheter (relative risk undefined, P<.001). Twenty-seven patients had blood cultures that grew K oxytoca, E cloacae, or both, and all had central venous catheters that were flushed with isotonic sodium chloride solution at the clinic from February 17 through March 3, 2004. Isolates of K oxytoca and E cloacae were matched by pulsed-field gel electrophoresis to K oxytoca and E cloacae isolates obtained from multiple predrawn syringes and from the intravenous fluid and administration set in use in the clinic at the time of its closing.

CONCLUSIONS

The injection of contaminated isotonic sodium chloride solution through the venous catheters of attendees at the clinic likely provided the opportunity for bloodstream infections in these 27 case patients. This outbreak highlights the need for continued emphasis on safe injection practices and suggests the need for guidelines and recommendations tailored to outpatient settings.

Saline‐Filled Breast Implant Contamination withCurvulariaSpecies among Women Who Underwent Cosmetic Breast Augmentation

BACKGROUND

During December 2000-July 2001, black sediment was noted in saline-filled silicone breast implants of women who had undergone revision surgery at facility A. Curvularia fungus was isolated from implant saline.

METHODS

To identify risk factors for contamination with Curvularia species, we performed case-control, retrospective cohort, and laboratory studies and conducted procedural reviews. A case patient was defined as any woman who underwent revision surgery at facility A between January 2000 and June 2001 and had black sediment in her implants.

RESULTS

Five patients met the case definition. Contamination was associated with having had surgery performed in operating room (OR) 2 (4/88 vs. 1/140; P=.07) and a longer duration of surgery (P<.001). A longer duration spent in the OR was an additional risk factor (P=.005). Curvularia fungus was isolated from the sterile supply room, where saline bottles had been stored under a water-damaged ceiling, and from the corridor outside OR 2; it was also found more commonly from facility A personnel than from non-facility A personnel (12/34 vs. 4/60; P<.001). Saline was warmed in a cabinet opposite OR 2, which was maintained at negative pressure differentials, then was poured into bowls open to the OR 2 environment before injection into implants.

CONCLUSION

Surgeons should always use closed systems to inflate breast implants. Surgery center infection control measures must include moisture control and balanced ventilation systems.

Why is an infection control program needed in the hemodialysis setting?

Infections account for the second leading cause of mortality among patients with end-stage renal disease. Many of these infections are due to sepsis, primarily arising from the vascular access site. Septicemia alone accounts for almost 11% of mortality in hemodialysis patients. Hemodialysis patients are also a sentinel population for the emergence of antimicrobial resistance, especially with regards to gram-positive cocci (vancomycin-resistant enterococci (VRE), methicillin resistant S. aureus (MRSA), Staphylococcus aureus with reduced susceptibility to vancomycin (VISA), and vancomycin resistant S. aureus [VRSA]). It is extremely important to follow infection control recommendations designed to prevent these types of adverse events from occurring in the hemodialysis population. The campaign to prevent antimicrobial resistance in dialysis includes four strategies: Prevent infection; diagnose and treat infection; use antimicrobials wisely; and prevent transmission. In addition, efforts to prevent infection should include avoiding use of hemodialysis catheters, whenever possible, and meticulous care of hemodialysis catheters and other vascular access sites. These efforts would improve patient outcomes and quality-of-life issues by reducing hospitalizations and mortality due to infection and vascular access complications.

Chlorine inactivation of bacterial bioterrorism agents

Seven species of bacterial select agents were tested for susceptibility to free available chlorine (FAC). Under test conditions, the FAC routinely maintained in potable water would be sufficient to reduce six species by 2 orders of magnitude within 10 min. Water contaminated with spores of Bacillus anthracis spores would require further treatment.

Mycobacterium goodii infections associated with surgical implants at Colorado hospital

From February to October 2003, Mycobacterium goodii wound infections were identified among three patients who received surgical implants at a Colorado hospital. This report summarizes the investigation of the first reported nosocomial outbreak of M. goodii. Increased awareness is needed about the potential for nontuberculous mycobacteria to cause postoperative wound infections.