Persistence ofLegionella Pneumophilain a Hospital's Water System: A 13-Year Survey

1999 ◽  
Vol 20 (12) ◽  
pp. 793-797 ◽  
Author(s):  
M. Sigfrido Rangel-Frausto ◽  
Paul Rhomberg ◽  
Richard J. Hollis ◽  
Michael A. Pfaller ◽  
Richard P. Wenzel ◽  
...  
Keyword(s):  
Water Supply ◽  
Legionella Pneumophila ◽  
Water System ◽  
University Teaching ◽  
University Of Iowa ◽  
System A ◽  
Sporadic Cases ◽  
Iowa Hospital ◽  
Different Strains ◽  
The University

AbstractObjective:To describe the molecular epidemiology ofLegionella pneumophilainfections in the University of Iowa Hospitals and Clinics (UIHC).Design:Molecular epidemiological study using pulsed-field gel electrophoresis (PFGE).Setting:A large university teaching hospital.Isolates:All surviving isolates obtained from culture-proven nosocomialL pneumophilainfections and all surviving isolates obtained from the University of Iowa Hospital and Clinics' water supply between 1981 and 1993.Results:Thirty-three isolates from culture-proven nosocomial cases ofL pneumophilapneumonia were available for typing. PFGE of genomic DNA from the clinical isolates identified six different strains. However, only strain C (16 cases) and strain D (13 cases) caused more than 1 case. Strain C caused clusters of nosocomial infection in 1981, 1986, and 1993 and also caused 4 sporadic cases. Strain D caused a cluster in 1987 and 1988 plus 4 sporadic cases. Of the six strains causing clinical infections, only strains C and D were identified in water samples. PFGE identified three strains in the water supply, of which strains C and D caused clinical disease and also persisted in the water supply during most of the study period.Conclusion:Specific strains ofL pneumophilacan colonize hospital water supplies and cause nosocomial infections over long periods of time.

scholarly journals Nosocomial Pneumonia Caused by Three Genetically Different Strains of Legionella pneumophila and Detection of These Strains in the Hospital Water Supply

1998 ◽  
Vol 36 (4) ◽  
pp. 1160-1163 ◽  
Author(s):  
P. Christian Lück ◽  
Hans-Martin Wenchel ◽  
Jürgen H. Helbig
Keyword(s):  
Water Supply ◽  
Nosocomial Pneumonia ◽  
Legionella Pneumophila ◽  
Water Samples ◽  
Clinical Specimen ◽  
Water System ◽  
Restriction Patterns ◽  
Dna Restriction ◽  
Different Strains

A 44-year-old woman developed Legionella pneumophilapneumonia after cerebral surgery. Initially, one colony from a clinical specimen and two colonies from water samples, all belonging to serogroup 12, did not match when their DNA restriction patterns were compared. When additional colonies from the water specimens were analyzed, a serogroup 12 strain complementary to that found in the clinical specimen was identified. Other colonies from the clinical specimen were identified as serogroup 12 strains complementary to those identified from the water. In addition, the same serogroup 1 strain was isolated from the patient and the water system.

Comparison of two molecular methods used for subtyping of Legionella pneumophila 1 strains isolated from a hospital water supply

2008 ◽  
Vol 58 (3) ◽  
pp. 683-688 ◽  
Author(s):  
B. Casini ◽  
P. Valentini ◽  
A. Baggiani ◽  
F. Torracca ◽  
C. Lorenzini ◽  
...  
Keyword(s):  
Water Supply ◽  
Legionella Pneumophila ◽  
Potable Water ◽  
Water System ◽  
Epidemiological Studies ◽  
Molecular Methods ◽  
Pfge Analysis ◽  
Typing Method ◽  
Electrophoretic Patterns ◽  
Low Degree

The results of the pulsed-field gel electrophoresis and the sequence-based typing (using the loci flaA, pilE, asd, mip, mompS and proA) were compared for subtyping of Legionella pneumophila 1 strains isolated from a hospital water supply. Molecular typing was carried out on 61 isolates (38% of the positive samples) selected on space and temporal criteria in order to follow the evolution of the water-system colonization. For all the 61 isolates, the sequence of the amplified mip gene fragment identified Legionella pneumophila strain Wadsworth. Genotype testing by PFGE analysis showed three different patterns, correspondent to three SBT types according to the allelic profiles. Both PFGE and SBT indicated the circulation and the persistence in the hospital potable water-system of three types randomly distributed in space and time. The two molecular methods adopted showed a 100% concordance, although a low degree of genetic heterogeneity characterized the isolates. The electrophoretic patterns were sufficiently unambiguous to consider PFGE a highly discriminatory typing method, but the SBT technique besides accurately characterizing isolates, was able to identify Legionella strains through analysis of the mip gene. A typing method with this level of discriminatory power has great potential for assisting in epidemiological studies.

Nosocomial Legionellosis Traced to a Contaminated Ice Machine

1997 ◽  
Vol 18 (09) ◽  
pp. 637-640 ◽  
Author(s):  
Paul S. Graman ◽  
Gail A. Quinlan ◽  
June A. Rank
Keyword(s):  
Sodium Hypochlorite ◽  
Legionella Pneumophila ◽  
Cold Water ◽  
Water System ◽  
Hot Water ◽  
University Teaching ◽  
Mouth Care ◽  
Colony Forming Units ◽  
And Control

Abstract Objective: To investigate a case of nosocomial legionellosis, identify pathways of transmission, and effect control of the environmental source. Design: Case investigation and environmental culture surveillance. Setting: A 720-bed university teaching hospital. Case Patient: A ventilator-dependent 66-year-old male developed nosocomial pneumonia due to Legionella pneumophila serogroup 6 after 3 months in an intensive-care unit (ICU). The patient had no intake of potable water except for ice chips from an ice machine in the ICU. Results: Cultures revealed L pneumophila serogroup 6 in the ice (4.3 colony-forming units/mL) and ice machine cold water (too numerous to count). Cultures from adjacent hot and cold taps, plus taps located near the patient, all were negative; ice machines and cold water on seven other patient units also were negative. Only sterile water had been used for tube feedings, mouth care, suctioning, and ventilator humidification. Hospital hot water previously had been colonized with L pneumophila serogroup 6, but all surveillance water cultures had been negative since chlorination of the hot-water system began the previous year; cold-water cultures had never before grown Legionella. The ice machine was disinfected with a 2-hour flush of 2.625% sodium hypochlorite. The supply line to the ice machine was replaced, and the cold-water pipe from the floor below was treated with 83 ppm sodium hypochlorite for 48 hours. All follow-up surveillance cultures of the ice machine remained negative through mid-1996. No additional cases of nosocomial legionellosis occurred. Conclusions: Ice machines may be reservoirs of L pneumophila in hospitals. Both ice and water dispensed from these machines may be contaminated, and nosocomial transmission may occur. Successful long-term decontamination and control can be accomplished with shock chlorination.

scholarly journals Inhibition effects of Gorge Fischer plumbing system on growth and amplification of Legionella Pneumophila with culture and PCR based on 16sRNA and mip genes

2021 ◽  
Author(s):  
Leila Barzegar ◽  
Ghader Ghanizadeh ◽  
Davoud Esmaeili
Keyword(s):  
Water Supply ◽  
Legionella Pneumophila ◽  
Water Samples ◽  
Cold Water ◽  
Water System ◽  
Supply System ◽  
Residual Chlorine ◽  
Plumbing System ◽  
Good Ability ◽  
The Mean

Abstract Background Legionella is an aquatic bacterium that causes Legionnaires' fever. Methods Fifty-six samples of the hot and cold-water system were collected. Characteristics of water samples were measured. Culture was performed in BCYE agar. Molecular identification was performed by PCR. Results The mean residual chlorine were 0.73 to 0.88 mg / l. Culture results were positive 58.8% of George Fischer and 23.5% of Ray Ho and 60% Taleghani hospital samples. PCR results based on 16sRNA were 35.2% of the George Fischer system, 45.4%, from Ray Ho piping and 54.5% from Taleghani hospital. the results of the mip gene, 82.3% of George Fischer, 54.5% of RayHo and 20% of Taleghani hospital were positive. Conclusion George Fischer’s Legionella stopper pipes and fittings have a good ability to control the growth Legion density in the indoor water supply system and can be considered as a suitable option for use in indoor plumbing and water supply.

scholarly journals A field study of the survival ofLegionella pneumophilain a hospital hot–water system

1990 ◽  
Vol 104 (3) ◽  
pp. 381-387 ◽  
Author(s):  
I. D. Farrell ◽  
J. E. Barker ◽  
E. P. Miles ◽  
J. G. P. Hutchison
Keyword(s):  
Water Supply ◽  
Legionella Pneumophila ◽  
Water Samples ◽  
Cold Water ◽  
Water System ◽  
Hot Water ◽  
Undetectable Level ◽  
Drain Water ◽  
Water Feed ◽  
And Control

SUMMARYThe colonization, survival and control ofLegionella pneumophilain a hospital hot–water system was examined. The organism was consistently isolated from calorifier drain–water samples at temperatures of 50°C or below, despite previous chlorination of the system. When the temperature of one of two linked calorifiers was raised to 60°C, by closing off the cold–water feed, the legionella count decreased from c. 104c.f.u./l to an undetectable level. However, 10 min after turning on the cold–water feed which produced a fall in calorifier temperature, the count in the calorifier drain water returned to its original level. Investigations revealed that the cold–water supply was continually feeding the calorifiers withL. pneumophila. Simple modifications in the design of the system were made so that the cold–water feed no longer exceeds 20°C; these measures have considerably reduced the number ofL. pneumophilareaching the calorifiers.

The consolidation of microscopy technology into a university research support facility: Reflections on the 1980's and projections for the 1990's at the university of iowa

1993 ◽  
Vol 51 ◽  
pp. 476-477
Author(s):  
Kenneth C. Moore
Keyword(s):  
Laser Scanning ◽  
Freeze Fracture ◽  
Freeze Substitution ◽  
Research Support ◽  
University Of Iowa ◽  
Staff Members ◽  
The Past ◽  
Research Grade ◽  
The University ◽  
Support Facility

The University of Iowa Central Electron Microscopy Research Facility(CEMRF) was established in 1981 to support all faculty, staff and students needing this technology. Initially the CEMRF was operated with one TEM, one SEM, three staff members and supported about 30 projects a year. During the past twelve years, the facility has replaced all instrumentation pre-dating 1981, and now includes 2 TEM's, 2 SEM's, 2 EDS systems, cryo-transfer specimen holders for both TEM and SEM, 2 parafin microtomes, 4 ultamicrotomes including cryoultramicrotomy, a Laser Scanning Confocal microscope, a research grade light microscope, an Ion Mill, film and print processing equipment, a rapid cryo-freezer, freeze substitution apparatus, a freeze-fracture/etching system, vacuum evaporators, sputter coaters, a plasma asher, and is currently evaluating scanning probe microscopes for acquisition. The facility presently consists of 10 staff members and supports over 150 projects annually from 44 departments in 5 Colleges and 10 industrial laboratories. One of the unique strengths of the CEMRF is that both Biomedical and Physical scientists use the facility.

Five Decades of Research Experience in Speech Anatomy and Physiology

2016 ◽  
Vol 1 (5) ◽  
pp. 4-12
Author(s):  
David P. Kuehn
Keyword(s):  
Ohio State University ◽  
State University ◽  
Research Experience ◽  
University Of Iowa ◽  
University Of Illinois ◽  
Anatomy And Physiology ◽  
The Ohio State University ◽  
Speech Science ◽  
The University ◽  
East Carolina University

This report highlights some of the major developments in the area of speech anatomy and physiology drawing from the author's own research experience during his years at the University of Iowa and the University of Illinois. He has benefited greatly from mentors including Professors James Curtis, Kenneth Moll, and Hughlett Morris at the University of Iowa and Professor Paul Lauterbur at the University of Illinois. Many colleagues have contributed to the author's work, especially Professors Jerald Moon at the University of Iowa, Bradley Sutton at the University of Illinois, Jamie Perry at East Carolina University, and Youkyung Bae at the Ohio State University. The strength of these researchers and their students bodes well for future advances in knowledge in this important area of speech science.

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