Prevenzione (2020 - 2017)
[ultimo
aggiornamento 25/11/2020]
Can mandatory monitoring
in rental apartments effectively prevent legionellosis? A retrospective analysis
of data from Regensburg with a review of the literature
Lampl BMJ,
Lang M, Wodnick S.
Public Health Department,
Regensburg, Germany. benedikt.lampl@lra-regensburg.de
GMS Hyg Infect Control
2020 Jun 30;15:Doc14.
Abstract: Background: Legionella pneumophila can
cause severe, often fatal, pneumonia in humans. Mandatory water sampling in
commercially used buildings (mainly rental apartments) as regulated in the
Drinking Water Ordinance (Trinkwasserverordnung) aim to protect the
population against infection with Legionella. However, no data exist to date
that could prove the effectiveness of the measures. At the same time, having the
Public Health Department's Infection Control Division deal with Legionella is
very time consuming. Methods: A
retrospective analysis of data from the city and district of Regensburg, a
selective literature search, a prospective survey of workload using an anonymous
questionnaire were performed. Results: The evaluated data from the city/district of
Regensburg suggest underreporting to a similar extent as shown by the RKI's data
in the compared period. Neither is the actual incidence known, nor can exposures
be clearly determined in most cases. The exposure categories "travel"
and "private/occupational" seem to be the most pertinent. The
potential public hazard of Legionella posed by domestic plumbing systems is
unclear. A connection between exceeding the technical measurement limit (TMW) in
routine tests in rental apartments and disease cases cannot be shown. A survey
among non-medical personnel in the field of infection control and hygiene on the
time spent on the topic of Legionella yielded a mean number of 39% of daily
working hours for the observed 2-month period. Conclusion: The
data on incidence, exposure, and causality are incomplete. Evidence of effective
protection by the current practice of sampling in apartment buildings could not
be found. For many aspects, there are no unambiguous data in the literature.
Restricting mandatory monitoring to certain public/commercial institutions
should be discussed, given the high workload for the Public Health Department
and the unproven protective effect. Further research on this topic is necessary.
Prevention and Control
of Legionella and Pseudomonas spp. Colonization in Dental Units
Tuvo B, Totaro M, Cristina ML, Spagnolo AM, Di Cave D,
Profeti S, Baggiani A, Privitera G, Casini B.
Department
of Translational Research, N.T.M.S., University of Pisa, Pisa, Italy. beatrice.casini@med.unipi.it
Pathogens
2020 Apr 21;9(4):305.
Abstract: Introduction: Dental Unit Waterlines (DUWLs)
have shown to be a source of Legionella infection. We report
the experience of different dental healthcare settings where a risk management
plan was implemented. Materials and
methods: In a Hospital Odontostomatology Clinic (HOC) and three
Private Dental Clinics (PDCs) housing 13 and six dental units (DUs),
respectively, an assessment checklist was applied to evaluate staff compliance
with guideline recommendations. DUWLs microbial parameters were investigated
before and after the application of corrective actions. Results: In
the HOC a poor adherence to good practices was demonstrated, whereas protocols
were carefully applied in PDCs. L. pneumophila sg 2-15 was
isolated in 31% (4/13) and 33% (2/6) of DUs in HOC and PDCs, respectively,
mainly from handpieces (32%, 6/19) with counts >102 colony-forming
units per milliliter (CFU/L), often associated with P. aeruginosa (68%,
13/19). The shock disinfection with 3% v/v hydrogen peroxide (HP) showed a
limited effect, with a recolonization period of about 4 weeks. Legionella was
eradicated only after 6% v/v HP shock disinfection and filters-installation,
whilst P. aeruginosa after the third shock disinfection with a
solution of 4% v/v HP and biodegradable surfactants. Conclusions: Our
data demonstrate the presence and persistence of microbial contamination within
the DUWLs, which required strict adherence to control measures and the choice of
effective disinfectants.
Ambrose M,
Kralovic SM, Roselle GA,, Rizzo V Jr,
Wainwright DL,
National
Infectious Diseases Service, Specialty Care Services, Veterans Health
Administration, Department of Veterans Affairs, Washington, District of
Columbia. Shantini.Gamage@va.gov
J Public
Health Manag Pract 2020 Mar/Apr;26(2):E1-E11.
Abstract:
Context: The
Veterans Health Administration requires implementation of Legionella prevention
policy in potable water systems at Department of Veterans Affairs (VA) medical
facilities across the United States and territories. Program: The
Veterans Health Administration Central Office program offices with expertise in
engineering and clinical aspects of Legionella prevention policy have
provided joint, structured on-site assistance to VA medical facilities for
consultation on policy implementation. Site visits included review of facility
documentation and data, discussions with staff, touring of buildings, and
development of recommendations. Implementation: Information
obtained from on-site consultative assistance provided to VA medical facilities
from December 2012 through January 2018 was reviewed to identify engineering and
clinical challenges and lessons from implementation of Legionella
prevention policy in VA health care buildings. Fifteen consultative site visits
were conducted during this period regarding implementation of Legionella
prevention and validation of effectiveness. Evaluation: It
was found that implementation of Legionella prevention policy in potable
water systems was complex and practices varied for each building. Common
implementation challenges included capability of applying engineering controls,
water stagnation, and assessment of health care association of Legionella
cases. Process challenges included routine verification of actions, methods for
assessing environmental validation data, and documentation of requirements. It
was found that consistent and data-driven implementation of policy is crucial
for an effective program. Discussion: Guidance
and standards documents in the community for Legionella prevention in
building water systems are often general in nature, but implementation requires
specific decisions and routine assessments and modifications to optimize
outcomes. This real-world review of challenges and lessons from a large health
care system with a detailed primary Legionella prevention policy informs
future development of guidance and policy, both within and external to VA, and
can provide insight to other health care facilities planning to implement
practices for water safety.
Pierre
D, Baron JL, Ma X, Sidari FP 3rd, Wagener MM, Stout
JE.
Special
Pathogens Laboratory, Pittsburgh, PA 15219, USA. jstout@specialpathogenslab.com
Pathogens 2019 Dec;8(4):295.
Abstract:
Testing drinking water systems for the presence of Legionella colonization
is a proactive approach to assess and reduce the risk of Legionnaires' disease.
Previous studies suggest that there may be a link between Legionella positivity
in the hot water return line or certain water quality parameters (temperature,
free chlorine residual, etc.) with distal site Legionella positivity.
It has been suggested that these measurements could be used as a surrogate for
testing for Legionella in building water systems. We evaluated
the relationship between hot water return line Legionella positivity
and other water quality parameters and Legionella colonization
in premise plumbing systems by testing 269 samples from domestic cold and hot
water samples in 28 buildings. The hot water return line Legionella positivity
and distal site positivity only demonstrated a 77.8% concordance rate. Hot water
return line Legionella positivity compared to distal site
positivity had a sensitivity of 55% and a specificity of 96%. There was poor
correlation and a low positive predictive value between the hot water return
line and distal outlet positivity. There was no correlation between Legionella distal
site positivity and total bacteria (heterotrophic plate count), pH, free
chlorine, calcium, magnesium, zinc, manganese, copper, temperature, total
organic carbon, or incoming cold-water chlorine concentration. These findings
suggest that hot water return line Legionella positivity and
other water quality parameters are not predictive of distal site positivity and
should not be used alone to determine the building's Legionella colonization
rate and effectiveness of water management programs
Legionellosis in Health Care
Facilities: State of the Art in Control and Prevention in Italy
Napoli C, De Giglio O, Bertamino E,
Montagna MT.
Department of
Medical Surgical Sciences and Translational Medicine, Sapienza University of
Rome, Rome, Italy. christian.napoli@uniroma1.it
Ann Ig 2019
Sep-Oct;31(5):474-481.
Abstract: Background: Nosocomial water systems
may be contaminated by Legionella spp; therefore, health care facilities
represent a potential health risk for patients and health care staff. Active,
well-planned clinical and environmental surveillance in hospitals is the most
important instrument of prevention. Aims and methods: The aim of the
present article was to outline the state of the art in legionellosis control and
prevention among Italian health care facilities by reporting some experiences in
the field. Results: Our results showed that Legionella spp.
are largely reported as both hospital water system contaminants and etiological
agents in water-related health care-associated infections (HCAI) in Italy. Among
the numerous sources of HCAI, water is the most investigated, although it has
been demonstrated that air sampling may provide additional information for risk
assessment. Conclusions: More appropriate risk assessment is needed,
especially in large facilities. In addition, more sensitive diagnostic tests
should be used and dedicated training courses should be implemented in health
care facilities.
Van Kenhove E, Dinne K, Janssens
A,
Research
Group Building Physics, Construction and Climate Control, Department of
Architecture and Urban Planning, Ghent University, Ghent, Belgium. elisa.vankenhove@ugent.be
Am J Infect Control 2019 Aug;47(8):968-978.
Hamilton
KA, Hamilton
MT, Johnson W, Jjemba P, Bukhari Z, LeChevallier
M, Haas CN, Gurian PL.
School for Sustainable Engineering and
the Built Environment, Arizona State University, Tempe, Arizona, USA. kerry.hamilton@asu.edu
Environ
Sci Technol 2019 Apr;53(8):4528-4541.
Abstract:
Legionella spp. is a key contributor to the United States waterborne
disease burden. Despite potentially widespread exposure, human disease is
relatively uncommon, except under circumstances where pathogen concentrations
are high, host immunity is low, or exposure to small-diameter aerosols occurs.
Water quality guidance values for Legionella are available for building
managers but are generally not based on technical criteria. To address this gap,
a quantitative microbial risk assessment (QMRA) was conducted using target risk
values in order to calculate corresponding critical concentrations on a
per-fixture and aggregate (multiple fixture exposure) basis. Showers were the
driving indoor exposure risk compared to sinks and toilets. Critical
concentrations depended on the dose response model (infection vs clinical
severity infection, CSI), risk target used (infection risk vs disability
adjusted life years [DALY] on a per-exposure or annual basis), and fixture type
(conventional vs water efficient or "green"). Median critical
concentrations based on exposure to a combination of toilet, faucet, and shower
aerosols ranged from ∼10-2 to
∼100 CFU per L and ∼101 to
∼103 CFU per L for
infection and CSI dose response models, respectively. As infection model results
for critical L. pneumophila concentrations were often below a feasible
detection limit for culture-based assays, the use of CSI model results for
nonhealthcare water systems with a 10-6 DALY pppy target (the
more conservative target) would result in an estimate of 12.3 CFU per L (arithmetic
mean of samples across multiple fixtures and/or over time). Single sample
critical concentrations with a per-exposure-corrected DALY target at each
conventional fixture would be 1.06×103 CFU per L (faucets),
8.84×103 CFU per L (toilets), and 14.4 CFU per L (showers).
Using a 10-4 annual infection risk target would give a 1.20×103 CFU
per L mean for multiple fixtures and single sample critical concentrations of
1.02×105, 8.59×105, and 1.40×103 CFU
per L for faucets, toilets, and showers, respectively. Annual infection
risk-based target estimates are in line with most current guidance documents of
less than 1000 CFU per L, while DALY-based guidance suggests lower critical
concentrations might be warranted in some cases. Furthermore, approximately
<10 CFU per mL L. pneumophila may be appropriate for healthcare or
susceptible population settings. This analysis underscores the importance of the
choice of risk target as well as sampling program considerations when choosing
the most appropriate critical concentration for use in public health guidance.
Environmental Surveillance of Legionellosis Within an Italian University
Hospital-Results of 15 Years of Analysis
LaganàP, Facciolà A, Palermo
R, Delia S.
Regional Reference Laboratory of Clinical and Environmental Surveillance
of Legionellosis, Branch of Messina, Department of Biomedical and Dental
Sciences and Morphofunctional Imaging, University of Messina, Messina, Italy. plagana@unime.it.
Int J
Environ Res Public Health 2019 Mar;16(7):1103.
Abstract:
Legionnaires' disease is normally acquired by inhalation of legionellae from a
contaminated environmental source. Water systems of large and old buildings,
such as hospitals, can be contaminated with legionellae and therefore represent
a potential risk for the hospital population. In this study, we demonstrated the
constant presence of Legionella in water samples from the water
system of a large university hospital in Messina (Sicily, Italy) consisting of
11 separate pavilions during a period of 15 years (2004-2018).
In total, 1346 hot water samples were collected between January 2004 and
December 2018. During this period, to recover Legionella spp.
from water samples, the standard procedures reported by the 2000 Italian
Guidelines were adopted; from May 2015 to 2018 Italian Guidelines revised in
2015 (ISS, 2015) were used. Most water samples (72%) were positive to L.
pneumophila serogroups 2-14, whereas L.
pneumophila serogroup 1 accounted for 18% and non-Legionella pneumophila spp.
accounted for 15%. Most of the positive samples were found in the buildings
where the following critical wards are situated: (Intensive Care Unit) ICU,
Neurosurgery, Surgeries, Pneumology, and Neonatal Intensive Unit Care. This
study highlights the importance of the continuous monitoring of hospital water
samples to prevent the potential risk of nosocomial legionellosis.
Alexandropoulou I, ,, Panopoulou M,
Laboratory of Hygiene and Environmental Protection, Medical School,
Democritus University of Thrace, Alexandroupolis, Greece. ialexand@med.duth.gr
Healthcare
(Basel) 2019 Mar;7(1):39.
Abstract:
A proactive environmental monitoring program was conducted to determine
the risk and prevent nosocomial waterborne infections of Legionella spp.
in infants. Sink taps in a neonatal intensive care unit (NICU) and two obstetric
clinics were monitored for Legionella spp. A total of 59 water
samples were collected during a 3-year period and 20 of them were found
colonized with Legionella pneumophila. Standard culture, molecular,
and latex agglutination methods were used for the detection and identification
of Legionella bacteria. Hospital personnel also proceeded with
remedial actions (hyperchlorination and thermal shock treatment) in the event of
colonization. The minimal inhibitory concentration (MIC) values of erythromycin,
ciprofloxacin was determined for Legionella isolates using the
e-test method. Our data indicate that the majority of neonatal sink-taps were
colonized at least once during the study with Legionella spp.
Among 20 isolates, 5 were considered as low-level resistant, 3 in erythromycin
and 2 in ciprofloxacin, while no resistant strains were detected. Environmental
surveillance in neonatal and obstetric units is suggested to prevent waterborne
infections, and thus to reduce the risk of neonatal nosocomial infections.
LecointeD,, Breton N, ,
Unité Fonctionnelle d'Hygiène Hospitalière et de Lutte contre les
Infections Nosocomiales, Centre Hospitalier Sud Francilien, Corbeil-Essonnes,
France. didier.lecointe@chsf.fr
Infect Dis
(Lond) 2019 Feb;51(2):102-112.
Ehret KM,
Chamberlain AT,
Berkelman RL, Fridkin SK.
Rollins School of
Public Health, Emory University, Atlanta, Georgia. allison.chamberlain@emory.edu
Infect Control Hosp Epidemiol 2018
Dec;39(12):1470-1472
Abstract:
In 2017, we surveyed 101 SHEA Research Network hospitals regarding Legionnaires'
disease (LD). Of 29 respondents, 94% have or are developing a water management
plan with varying characteristics and personnel engaged. Most LD diagnostic
testing is limited to urine antigen testing. Many opportunities to improve LD
prevention and diagnosis exist.
Montagna MT, De Giglio O, Napoli C,
Diella G, Rutigliano S, Agodi A, Auxilia F, Baldovin T, Bisetto F, Arnoldo L,
Brusaferro S, Busetti M, Calagreti G, Casini B, Cristina ML, Di Luzio R, Fiorio
M, Formoso M, Liguori G, Martini E, Molino A, Mondello P, Mura I, Novati R, Orsi
GB, Patroni A, Poli A, Privitera G, Ripabelli G, Rocchetti A, Rose F, Sarti M,
Savini S, Silvestri A, Sodano L, Spagnolo AM, Tardivo S, Teti V, Torregrossa MV,
Torri E, Veronesi L, Zarrilli R, Pacifico C, Goglio A, Moro M, Pasquarella C.
Department of Biomedical Science and
Human Oncology, University of Bari Aldo Moro, Bari, Italy. mariateresa.montagna@uniba.it
Environ
Res 2018 Oct;166:55-60.
Abstract:
Risk assessment, environmental monitoring, and the disinfection of water
systems are the key elements in preventing legionellosis risk. The Italian Study
Group of Hospital Hygiene of the Italian Society of Hygiene, Preventive
Medicine, and Public Health and the Italian Multidisciplinary Society for the
Prevention of Health Care-Associated Infections carried out a national
cross-sectional survey to investigate the measures taken to prevent and control
legionellosis in Italian hospitals. A multiple-choice questionnaire was
developed, comprising 71 questions regarding hospital location, general
characteristics, clinical and environmental surveillance, and control and
preventive measures for legionellosis in 2015. Overall, 739 hospitals were
enrolled from February to June 2017, and 178 anonymous questionnaires were
correctly completed and evaluated (response rate: 24.1%). The survey was
conducted using the SurveyMonkey® platform, and the data were analyzed using
Stata 12 software. Of the participating hospitals, 63.2% reported at least one
case of legionellosis, of which 28.2% were of proven nosocomial origin. The
highest case numbers were reported in the Northern Italy, in hospitals with a
pavilion structure or cooling towers, and in hospitals with higher numbers of
beds, wards and operating theaters. Laboratory diagnosis was performed using
urinary antigen testing alone (31.9%), both urinary antigen testing and single
antibody titer (17.8%), or with seroconversion also added (21.5%). Culture-based
or molecular investigations were performed in 28.8% and 22.1% of the clinical
specimens, respectively. The water systems were routinely tested for Legionella
in 97.4% of the hospitals, 62% of which detected a positive result (>1000 cfu/L).
Legionella pneumophila serogroup 2-15 was the most frequently isolated
species (58.4%). The most common control measures were the disinfection of the
water system (73.7%), mostly through thermal shock (37.4%) and chlorine dioxide
(34.4%), and the replacement (69.7%) or cleaning (70.4%) of faucets and
showerheads. A dedicated multidisciplinary team was present in 52.8% of the
hospitals, and 73% of the hospitals performed risk assessment. Targeted training
courses were organized in 36.5% of the hospitals, involving nurses (30.7%),
physicians (28.8%), biologists (21.5%), technicians (26.4%), and cleaners (11%).
Control and prevention measures for legionellosis are present in Italian
hospitals, but some critical aspects should be improved. More appropriate risk
assessment is necessary, especially in large facilities with a high number of
hospitalizations. Moreover, more sensitive diagnostic tests should be used, and
dedicated training courses should be implemented.
Jinna S,
Department of
Microbiology, All India Institute of Medical Sciences, Raipur, India. ujugaikwad@gmail.com
Indian J Med Res 2018
Jun;147(6):611-614.
Abstract: Background & objectives: Legionella pneumophila, a ubiquitous aquatic organism is
found to be associated with the development of the community as well as
hospital-acquired pneumonia. Diagnosing Legionella infection is difficult
unless supplemented with, diagnostic laboratory testing and established evidence
for its presence in the hospital environment. Hence, the present study was
undertaken to screen the hospital water supplies for the presence of L.
pneumophila to show its presence in the hospital environment further
facilitating early diagnosis and prevention of hospital-acquired legionellosis. Methods: Water
samples and swabs from the inner side of the same water taps were collected from
30 distal water outlets present in patient care areas of a tertiary care
hospital. The filtrate obtained from water samples as well as swabs were
inoculated directly and after acid buffer treatment on plain and selective (with
polymyxin B, cycloheximide and vancomycin) buffered charcoal yeast extract
medium. The colonies grown were identified using standard methods and confirmed
for L. pneumophila by latex agglutination test. Results: About
6.66 per cent (2/30) distal water outlets sampled were found to be contaminated
with L. pneumophila serotype 2-15. Isolation was better with swabs
compared to water samples. Interpretation & conclusions: The
study showed the presence of L. pneumophila colonization of hospital
water outlets at low levels. Periodic water sampling and active clinical
surveillance in positive areas may be done to substantiate the evidence, to
confirm or reject its role as a potential nosocomial pathogen in hospital
environment.
Danila RN, Koranteng N,
Como-Sabetti KJ,, Laine ES
Minnesota Department
of Health, St Paul, Minnesota, USA. richard.danila@state.mn.us
Infect
Control Hosp Epidemiol 2018 Mar;39(3):336-338.
Abstract:
Infection preventionists at Minnesota hospitals were surveyed to determine
whether they had Legionella water management plans. Of 137 hospitals, 84
(61%) responded. Among them, 27% hospitals had a water management plan, 21%
regularly sampled for Legionella, and 51% had knowledge of ASHRAE Legionella
prevention standards. Significant changes are needed to protect patients from
nosocomial infection.
Benedict KM, Reses H, Vigar M, Roth DM, Roberts VA, Mattioli
M, Cooley LA, Hilborn ED, Wade TJ, Fullerton KE, Yoder JS, Hill VR.
Epidemic Intelligence Service,
CDC; kbenedict@cdc.gov
MMWR Morb Mortal Wkly Rep 2017 Nov;66(44):1216-1221.
