- Email: [email protected]
Characterization of NDM-1- and OXA-23-producing Acinetobacter baumannii isolates from inanimate surfaces in a hospital environment in Algeria
Accepted Manuscript Characterization of NDM-1- and OXA-23-producing Acinetobacter baumannii isolates from inanimate surfaces in a hospital environment in Algeria K. Zenati, A. Touati, S. Bakour, F. Sahli, J.M. Rolain PII:
S0195-6701(15)00398-9
DOI:
10.1016/j.jhin.2015.09.020
Reference:
YJHIN 4658
To appear in:
Journal of Hospital Infection
Received Date: 7 July 2015 Accepted Date: 28 September 2015
Please cite this article as: Zenati K, Touati A, Bakour S, Sahli F, Rolain JM, Characterization of NDM-1- and OXA-23-producing Acinetobacter baumannii isolates from inanimate surfaces in a hospital environment in Algeria, Journal of Hospital Infection (2015), doi: 10.1016/j.jhin.2015.09.020. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
K. Zenati et al.
Characterization of NDM-1- and OXA-23-producing Acinetobacter baumannii isolates from inanimate surfaces in a hospital environment in Algeria K. Zenatia,b, A. Touatib, S. Bakoura,b, F. Sahlic, J.M. Rolaina,* a
Unité de recherche sur les maladies infectieuses et tropicales émergentes (URMITE), UM 63,
CNRS 7278, IRD 198, INSERM 1095, IHU Méditerranée Infection, Faculté de Médecine et de b c
RI PT
Pharmacie, Aix-Marseille-Université, Marseille, France
Laboratoire d’Ecologie Microbienne, FSNV, Université de Bejaia, 06000 Bejaia, Algeria
Laboratoire de Microbiologie, CHU de Sétif, Algeria
______________________ *
SC
Corresponding author. Address: IHU Méditérranée Infectiopole Sud, URMITE, 27
Boulevard Jean Moulin, Marseille, 13010, France. Tel.: +33 4 91 32 43 75; fax: +33 4 91 38
M AN U
77 72.
AC C
EP
TE D
E-mail address: [email protected] (J.M. Rolain).
1
ACCEPTED MANUSCRIPT
SUMMARY
Background: Investigation of several outbreaks of multidrug-resistant Acinetobacter baumannii infection has demonstrated that contamination of the inanimate hospital environment could be implicated in the spread of these multidrug-resistant strains. Aim: To investigate the occurrence of carbapenem-resistant A. baumannii on inanimate surfaces and possible dissemination in the hospital environment in Algeria as a potential
RI PT
source of infection in humans.
Methods: A. baumannii strains were isolated from the hospital environment and identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility was determined using disc diffusion and E-test methods.
SC
Carbapenemase activity was detected using microbiological tests, including modified Hodge test, modified Carba NP test, and EDTA test. Carbapenem resistance determinants were
M AN U
studied by polymerase chain reaction (PCR) and sequencing. Clonal relatedness was determined using multi-locus sequence typing (MLST).
Results: A total of 67 A. baumannii isolates were obtained from 868 environmental samples and identified by MALDI-TOF MS. Among them, 61 isolates were resistant to imipenem with minimum inhibitory concentration >32 µg/mL and positive by the modified Hodge test and modified Carba NP test. In addition, the activity of carbapenemase was inhibited by
TE D
EDTA in 32 strains. PCR and sequencing showed the presence of blaOXA-23 gene in 29 strains, and the blaNDM-1 gene in 32 isolates. MLST demonstrated the presence of five types of ST (ST19, ST2, ST85, ST98, and ST115).
Conclusion: Our study demonstrated the dissemination of carbapenemase-producing A.
EP
baumannii strains recovered from inanimate surfaces in a hospital environment, surrounding patients, healthcare workers and visitors, in Algeria as a potential source for nosocomial
AC C
infection. Keywords:
Acinetobacter baumannii Carbapenemases
Hospital environment NDM-1 Nosocomial infection OXA-23 Introduction
Hospital surfaces play an important role in nosocomial infections. The healthcare environment contains a diverse population of micro-organisms and can serve as reservoirs of
ACCEPTED MANUSCRIPT
potential pathogens.1 Acinetobacter baumannii has emerged as an important infectious agent in hospitalized patients worldwide and especially in developing countries.2 In general, the success of A. baumannii can be attributed to: (i) its ability to form biofilms and resist desiccation on abiotic surfaces (i.e. medical devices and environmental surfaces); (ii) its ability to adhere, to colonize and to invade human epithelial cells; (iii) its repertoire of antibiotic resistance mechanisms that are able to be promptly up-regulated as required; and
RI PT
(iv) its ability to acquire foreign genetic material through lateral gene transfer to promote its own survival under antibiotic and host selection pressures.3 Investigation of several outbreaks of multidrug-resistant A. baumannii infection has demonstrated that the contamination of the inanimate hospital environment could be implicated in the spread of these multidrug-resistant
SC
strains.2,4,5 The most frequent means of transmission occurs via hands of health professionals, patients, contaminated hospital surfaces, and medical equipment.6,7
M AN U
The emergence of carbapenem resistance in A. baumannii has become a significant public health concern. Three types of enzyme capable of hydrolysing carbapenems have been reported in A. baumannii: (i) β-lactamases inhibited by clavulanic acid (Ambler class A) such as KPC-2 and GES-14; (ii) metallo-β-lactamases (Ambler class B) such as IMP-1, VIM-2, SIM-1, and NDM-1; and (iii) Ambler class D β-lactamases, which are referred to as oxacillinases such as OXA-23, OXA-24 and OXA-58.8 Carbapenem resistance in A.
TE D
baumannii is mostly associated with OXA-type β-lactamases, especially OXA-23, which have a higher dissemination worldwide and have also been reported from African countries, but NDM-1-like enzymes have been increasingly reported.9,10 Outbreaks of carbapenemase-producing A. baumannii strains isolated from the
EP
hospital environment have been documented in diverse geographical areas including Europe, Asia, and the Middle East.2,5,11,12 In Algeria, the dissemination of carbapenemases, such as the
AC C
blaOXA-23-like, blaOXA-24-like, blaOXA-58-like and blaNDM-1 genes among A. baumannii isolated from clinical samples, has been reported in previous studies but there is currently little information on the dissemination of theses carbapenemases into the hospital environment in Algeria.13‒15 Touati et al. have reported in a previous study the characterization of extended-spectrum βlactamase-producing Enterobacteriaceae strains isolated from a hospital environment in Bejaia (Algeria).16,17 In addition, imipenem-resistant A. baumannii isolated from inanimate surfaces was reported by Mesli et al. in western Algeria.14 The aim of our present study was to characterize the molecular epidemiology and mechanisms of carbapenem resistance of A. baumannii isolated from the inanimate surfaces of the hospital environment in two university hospitals in Algeria (Sétif and Bejaia). Methods
ACCEPTED MANUSCRIPT
Study design
The study was performed from January 2011 to March 2013 in the 900-bed Sétif teaching hospital and the 425-bed Bejaia teaching hospital. The hospitals contain both medical and chirurgical wards. A total of 868 environmental samples were obtained while the patient and healthcare personnel occupied the room and from adjacent equipment of four wards including intensive
RI PT
care unit (ICU), infectious diseases, medical, and paediatric wards from the two hospitals. Different samples were collected from several frequently contacted surfaces. Bacterial isolates
At each site, an area of ~25 cm2 was sampled using a sterile cotton swab previously
SC
moistened with Nutrient Broth Medium.18 Swabs for each surface type were cultured in the Nutrient Broth Medium and incubated at 37°C for 24 to 48 h. The strains were isolated on
M AN U
MacConkey agar plates containing ceftazidime (4 mg/L). They were first identified by conventional methods (Gram stains and biochemical tests) and confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).19 Antimicrobial susceptibility
Antibiotic susceptibility was determined on the Mueller‒Hinton agar using the standard disc diffusion procedure as recommended by the European Committee on
TE D
Antimicrobial Susceptibility Testing (EUCAST).20 Sixteen antibiotics were tested, including ticarcillin, ticarcillin–clavulanate, piperacillin, piperacillin–tazobactam, ceftazidime, imipenem, aztreonam, amikacin, tobramycin, kanamycin, gentamicin, ciprofloxacin, tigecyclin, cotrimoxazol, rifampin, and colistin (Bio-Rad, Hercules, CA, USA). Minimum
EP
inhibitory concentrations (MICs) of imipenem were determined using the E-test method (AB Biodisk, Solna, Sweden). The results were interpreted according to the recommendations of
AC C
EUCAST.20
β-Lactamase assays
The modified Hodge test and the modified Carba NP test were used to confirm the
carbapenemase production as described by Bakour et al.21 Metallo-β-lactamase was detected by EDTA-disc synergy test as previously described.22 Molecular analysis Genotypic detection of carbapenemase-encoding genes was carried out by real-time and standard polymerase chain reaction (PCR) targeting blaOXA-23, blaOXA-24, blaOXA-58, blaOXA-51, and blaNDM-1 genes in all A. baumannii strains as described previously.23 Molecular epidemiology
ACCEPTED MANUSCRIPT
Multi-locus sequencing typing (MLST) was performed using seven conserved housekeeping genes (cpn60, fusA, gltA, pyrG, recA, rplB, and rpoB) according to Pasteur schemes available at the Institute Pasteur MLST web site (www.pasteur.fr/mlst). DNA sequencing PCR products were purified and sequenced using Big Dye terminator chemistry on an ABI 3730 automated sequencer (Applied Biosystems, Foster City, CA, USA). The sequences
RI PT
obtained were analysed using BlastN and BlastP against the NCBI database (www.ncbi.nlm.nih.gov). Results Bacterial strains
SC
Sixty-seven A. baumannii isolates were taken from the 868 environmental samples (7.7%) and identified as A. baumannii both by conventional methods and by MALDI-TOF
M AN U
MS and confirmed by the presence of the blaOXA-51-like gene in all of the isolates. Fifty-one A. baumannii strains were isolated from Sétif hospital and 16 strains from Bejaia hospital. The isolates were recovered mainly from handles (13/67), bed sheets (12/67), medical equipment (13/67), medical equipment trolleys (5/67), and from bed rails (4/67). The distribution of the cultures from environmental samples and the number of bacteria isolated are shown in Table I.
TE D
Antimicrobial susceptibility
Antibiotic susceptibility testing revealed that the isolates showed a high resistance to almost all antibiotics tested, including β-lactams, aminoglycosides, and fluoroquinolones (Figure 1). Among the 67 A. baumannii isolates, 61 showed high-level resistance to
EP
carbapenems (91%) with high imipenem minimum inhibitory concentration (>32 mg/L) (Table II). Colistin and rifampin showed efficacy against all strains except one strain that was
AC C
resistant to rifampin. The modified Hodge test and the modified Carba NP test were positive for all imipenem-resistant A. baumannii isolates, whereas β-lactamase activity was inhibited by EDTA for 32 A. baumannii isolates. Resistance-gene determination PCR detected the presence of genes encoding blaOXA-23 in 29 isolates (27 from Sétif
and two from Bejaia), and blaNDM-1 in 32 isolates (18 from Sétif and 14 from Bejaia) (Table II). The blaOXA-23 gene was isolated only in an infectious diseases ward in Sétif hospital compared with the same wards in Bejaia hospital, and the blaNDM-1 gene was isolated only in the medical ward in Bejaia hospital compared with the same wards in Sétif hospital (Table II). MLST
ACCEPTED MANUSCRIPT
The clonal relationship of isolates analysed by MLST showed diversity in the sequences found. Five sequence types (ST19, ST2, ST85, ST98, and ST115) were found in Sétif hospital, whereas only two (ST2 and ST85) were found in Bejaia hospital (Table II). All strains of A. baumannii producing metallo-β-lactamase enzyme NDM-1 belonged to ST85. Unlike ST19 and ST2, types ST98 and ST115 were observed in strains producing OXA-23 (Table II).
RI PT
Discussion
The hospital environment provides an important ecological niche for micro-organisms that could have clinical significance.24 It is thought that A. baumannii strains found in the environment may be a source for contamination and spread among patients.25 The present
and equipment within two Algerian hospitals.
SC
study showed significant colonization of A. baumannii isolates on different inanimate surfaces
M AN U
A. baumannii strains may survive in humid environments, such as ventilator devices in hospitals, and also in dry conditions for extended periods and thus facilitate transmission between patients and healthcare workers.25,26 Contamination of the environment surrounding patients such as handles, bed sheets, bed rails, bedside, hands of the healthcare workers, and medication trolleys and equipment have been reported previously in the literature, and therefore the environment was considered as the main source of A. baumannii transmission
TE D
and of several outbreaks.2,5,11 Primary transmission of pathogens on to surfaces originates from hands, patients, hospital water systems, and airborne sources.26 In published data about A. baumannii outbreaks, patient environment, medical equipment or healthcare workers were reported to be colonized. In a study from Turkey, an outbreak in a neonatal ICU revealed that
EP
contamination was particularly evident on intubation devices and suction tools. The pulsedfield gel electrophoresis study showed that the strains from devices, healthcare workers’
AC C
hands, and clinical samples were the same clone.27 In Taiwan, microbial contamination of airborne and surface (medication trolley, bedrail, cabinet, respirator) suggested a higher relative risk among infected patients in the presence of the pathogens as compared to the absence of pathogens.28 Environmental contamination with multidrug-resistant A. baumannii assumes a greater importance when patients are managed in wards with shared facilities; the finding of bacterial contamination of near-patient surfaces and medical equipment could explain the results obtained in our study. Strains isolated in our study were found to be multidrug resistant. When we compared our results with published clinical imipenem-resistant A. baumannii isolates in Algeria, we observed the same high frequency of antibiotic-resistant strains on both hospital surfaces and clinical samples.13‒15 Markogiannakis et al. have reported A. baumannii clonal strains causing
ACCEPTED MANUSCRIPT
episodes of sepsis in a trauma ICU in Greece isolated from inanimate surfaces and healthcare workers, resistant to tobramycin, colistin, gentamicin, and meropenem.4 In our study, we found imipenem-resistant A. baumannii on the uniform and hands of staff, bench tops, trolleys, and medical equipment. These surfaces are often touched by healthcare workers during routine patient care and may act as a possible source of nosocomial prevent contact isolation of colonized and infected patients.11
RI PT
infection.29 This finding can be explained by insufficient handwashing and the inability to
Since 2009, the blaOXA-23 gene has become the most prevalent carbapenemase-
encoding gene circulating in the Mediterranean region.30 Global dissemination of the blaNDM-1 gene has been extensively described since its first report in K. pneumoniae in India.31
SC
Previous reports from Algeria have revealed that resistance to carbapenems in A. baumannii clinical isolates is mainly mediated by class D (oxacillinase) carbapenemases (OXA-23,
M AN U
OXA-24, OXA-58) and by class B (metallo-β-lactamase) carbapenemase NDM-1.13,14,15,32 However, environmental imipenem-resistant A. baumannii isolates from inanimate surfaces producing OXA-23 and OXA-24 have been reported only by Mesli et al. from west Algerian hospitals.14 In Jordan, multidrug-resistant A. baumannii strains producing OXA-23, OXA-24, and OXA-51 enzymes isolated in ICUs were reported in the hospital environment, especially in water and moist environments.2
TE D
Our study described 29 carbapenem-resistant A. baumannii isolates harbouring the blaOXA-23 gene and 32 isolates harbouring the blaNDM-1 gene besides blaOXA-51. Few MBL-producing Acinetobacter spp. have been identified from inanimate surfaces in hospital environments. NDM-1-producing Acinetobacter pittii was isolated from inanimate
EP
surfaces (equipment buttons, bed sheets, chairs, water taps, drawer handles, and air) in an ICU in China.33 VIM-producing A. baumannii (VIM-1 and VIM-4) were isolated from the floor,
AC C
beds and external sites of the ventilator tube in an ICU in Greece.34 To our knowledge, no report concerning the isolation of NDM-1-producing A. baumannii in Algerian hospitals environment has been published. This finding indicated that inanimate surface transmission might contribute to the
spread of carbapenem-resistant A. baumannii, which is in line with earlier studies on outbreaks of carbapenem-resistant Acinetobacter species, suggesting environmental transmission.4,33 The origin and spread of NDM-1-positive A. baumannii in this study remains unknown. NDM-producing A. baumannii were recovered from different wards in various samples (washbasins, bed sheets, faucets, medical equipment trolleys, microwaves) except in the infectious diseases ward from Sétif hospital. This finding can be explained by the fact that
ACCEPTED MANUSCRIPT
the first NDM-1-positive A. baumannii was isolated in 2012 from patient samples in the same ward in Sétif hospital by Bakour et al.32 Unlike our study, no NDM-1-positive A. baumannii was isolated from clinical samples in Bejaia hospital by the same authors in a later study.21 In Sétif hospital, the first carbapenemase genes detected in clinical A. baumannii were blaOXA-23 and blaOXA-72 genes in 2010 followed by blaNDM-1 in 2012.13,32 In Bejaia hospital, only blaOXA-23 has been reported since 2012. Today, the novelty in Algerian hospitals is the
RI PT
emergence and dissemination of blaNDM-1 from clinical samples to the hospital environment since 2012.
In our study, the carbapenemase-producing A. baumannii strains isolated from the hospital environment belong to ST85, ST2, ST19, ST98, and ST115. Previous studies
SC
reported that the A. baumannii strains isolated from Algerian patients belonged to ST1, ST2, ST19, ST25, ST85, and ST95.32
The study of the clonal typing revealed that the environmental strains have the same
M AN U
STs as the clinical strains previously reported: OXA-23 (ST2 and ST19), NDM-1 (ST85).32 However, new sequence types (ST98 and ST115) were reported for the first time in Algeria in Sétif hospital (infectious ward). The ST115 was reported in 2011 (one strain isolated in 2008) and the ST98 was reported in 2014 (25 strains isolated in 2009) in Italian and Portuguese hospitals respectively.35,36 These strains were certainly imported and persisted in the
TE D
environment without clinical incidence. These results confirm the clonal diversity among the A. baumannii clinical and environmental isolates in Algeria. In Mediterranean countries, including Algeria, the main clone isolated harbouring NDM-1-producing A. baumannii belonged to ST85; however, the ST2 belonged to the
EP
International clone II.30,37
In addition, the detection of common clones among environmental and clinical
AC C
imipenem-resistant isolates of A. baumannii suggests that environmental contamination might have contributed to the difficulty in restricting the spread of these organisms in the wards and hospitals. Environmental surveillance and strict antiseptic techniques may have contributed to the reduced spread of these bacteria.34 One limitation of this study was that we included only environmental isolates so that
comparison with clinical isolates was not performed. In conclusion, the presence of clonal isolates producing OXA-23 and NDM-1 enzymes in the hospital environment may act as a reservoir of resistance genes which can be transmitted horizontally to other isolates (clinical or environmental). In addition, it may be a risk factor for nosocomial outbreaks. This study highlights the complexity of the molecular epidemiology of A. baumannii in the hospital environment during non-outbreak periods.
ACCEPTED MANUSCRIPT
Education of environmental services and nursing staff, enhanced cleaning of frequently contaminated areas, and potentially routine screening of environmental surfaces to ensure adequate cleaning may help to limit the spread of multidrug-resistant strains in the hospital environment and reduce the risk of an epidemic. Acknowledgement We thank L. Hadjadj for technical assistance.
RI PT
Conflict of interest statement None declared. Funding source
This work was partly funded by CNRS and IHU Méditerranée Infection.
1.
SC
References
Jalalpoor S. Study of the antibiotic resistance pattern among the bacteria isolated from
2011;5:3317‒3320. 2.
M AN U
the hospital environment of Azzahra Hospital, Isfahan, Iran. Afr J Microbiol Res
Obeidat N, Jawdat F, Al-Bakri AG. Major biologic characteristics of Acinetobacter baumannii isolates from hospital environmental and patient’s respiratory tract sources. Am J Infect Control 2014;42:40140‒40144.
3.
Cerqueira GM, Peleg AY. Insights into Acinetobacter baumannii pathogenicity. IUBMB
4.
TE D
Life 2011;63:1055‒1060.
Markogiannakis A, Fildisis G, Tsiplakou S, et al. Cross-transmission of multidrugresistant Acinetobacter baumannii clonal strains causing episodes of sepsis in a trauma intensive care unit. Infect Control Hosp Epidemiol 2008;29:410‒417. Bourigault C, Corvec S, Bretonnière C, et al. Investigation and management of
EP
5.
multidrug-resistant Acinetobacter baumannii spread in a French medical intensive care
6.
AC C
unit: one outbreak may hide another. Am J Infect Control 2013;41:652‒655. Oliveira AC, Damasceno QS. Surfaces of the hospital environment as possible deposits of resistant bacteria: a review. Rev Esc Enferm USP 2010;44:1112‒1117. 7.
Weber DJ, Rutala WA. Understanding and preventing transmission of healthcare associated pathogens due to the contaminated hospital environment. Infect Control and Hosp Epidemiol 2013;34:450‒452.
8.
Kempf M, Rolain JM. Emergence of resistance to carbapenems in Acinetobacter baumannii in Europe: clinical impact and therapeutic options. Int J Antimicrob Agents 2012;39:105‒119.
9.
ACCEPTED MANUSCRIPT
Jones LS, Toleman MA, Weeks JL, Howe RA, Walsh TR, Kumarasamy KK. Plasmid carriage of blaNDM-1 in clinical Acinetobacter baumannii isolates from India. Antimicrob Agents Chemother 2014;58:4211‒4213.
10.
Revathi G, Siu LK, Po-Liang, Huang LY. First report of NDM-1-producing Acinetobacter baumannii in East Africa. Int J Infect Dis 2013;17:1255‒1258.
11.
Aygün G, Demirkiran O, Utku T, et al. Environmental contamination during
RI PT
carbapenem resistant Acinetobacter baumannii outbreak in an intensive care unit. J Hosp Infect 2002;52:259‒262. 12.
Zhang R, Hu YY, Yang XF, et al. Emergence of NDM-producing non-baumannii Acinetobacter spp. isolated from China. Eur J Clin Microbiol Infect Dis
13.
SC
2014;33:853‒860.
Bakour S, Kempf M, Touati A, et al. Carbapenemase-producing Acinetobacter
14.
M AN U
baumannii in two university hospitals in Algeria. J Med Microbiol 2012;61:1341‒1343. Mesli E, Berrazeg M, Drissi M, Bekkhoucha SN, Rolain JM. Prevalence of carbapenemase-encoding genes including New Delhi metallo-beta-lactamase in Acinetobacter species, Algeria. Int J Infect Dis 2013;17:739‒743. 15.
Touati M, Diene SM, Racherache A, Dekhil M, Djahoudi A, Rolain JM. Emergence of blaOXA-23 and blaOXA-58 carbapenemase-encoding genes in multidrug-resistant
TE D
Acinetobacter baumannii isolates from University Hospital of Annaba, Algeria. Int J Antimicrob Agents 2012;40:89‒91. 16.
Touati A, Benallaoua S, Djoudi F, Madoux J, Brasme L, De Champs C. Characterization of CTX-M-15-producing Klebsiella pneumoniae and Escherichia coli
EP
strains isolated from hospital environments in Algeria. Microb Drug Resist 2007;13:85‒89.
Touati A, Zenati K, Brasme L, Benallaoua S, De Champs C. Extended-spectrum β-
AC C
17.
lactamase characterisation and heavy metal resistance of Enterobacteriaceae strains isolated from hospital environmental surfaces. J Hosp Infect 2010;75:78‒79. 18.
French GL, Otter JA, Shannon KP, Adams NMT, Watling D, Parks MJ. Tackling contamination of the hospital environment by methicillin-resistant Staphylococcus aureus (MRSA): a comparison between conventional terminal cleaning and hydrogen peroxide vapour decontamination. J Hosp Infect 2004;57:31‒37.
19.
Seng P, Drancourt M, Gouriet F, et al. Ongoing revolution in bacteriology: routine identification of bacteria by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Clin Infect Dis 2009;49:543‒551.
20.
ACCEPTED MANUSCRIPT
European Committee on Antimicrobial Susceptibility Testing. Breakpoint tables for interpretation of MICs and zone diameters. Version 1.0. EUCAST; 2014. http://www.eucast.org.
21.
Bakour S, Olaitan AO, Ammari H, et al. Emergence of colistin- and carbapenemresistant Acinetobacter baumannii ST2 clinical isolates in Algeria: first case report. Microb Drug Resist 2015;21:279‒285. Jeong SH, Bae IK, Park KO, et al. Outbreaks of imipenem-resistant Acinetobacter
RI PT
22.
baumannii producing carbapenemases in Korea. J Microbiol 2006;44:423‒431. 23.
Mendes RE, Kiyota KA, Monteiro J, et al. Rapid detection and identification of metallobeta-lactamase-encoding genes by multiplex real-time PCR assay and melt curve
24.
SC
analysis. J Clin Microbiol 2007;45:544‒561.
Dancer SJ, Coyne M, Robertson C, Thomson A, Guleri A, Alcock A. Antibiotic use is
Infect 2006;62:200‒206. 25.
M AN U
associated with resistance of environmental organisms in a teaching hospital. J Hosp
Kirkgöz E, Zer Y. Clonal comparison of Acinetobacter strains isolated from intensive care patients and the intensive care unit environment. Turk J Med Sci 2014;44:643‒648.
26.
Cahill OJ, Claro T, O’Connor N, et al. Cold air plasma to decontaminate inanimate surfaces of the hospital environment. Appl Environ Microbiol 2014;80:2004‒2010. Hosoglu S, Hascuhadar M, Yasar E, Uslu S, Aldudak B. Control of an Acinetobacter
TE D
27.
baumannii outbreak in a neonatal ICU without suspension of service: a devastating outbreak in Diyarbakir, Turkey. Infection 2012;40:11‒18. 28.
Huang PY, Shi ZY, Chen CH, Den W, Huang HM, Tsai JJ. Airborne and surface-bound
EP
microbial contamination in two intensive care units of a medical center in central Taiwan. Aerosol Air Qual Res 2013;13:1060‒1069. Thom KA, Johnson K, Lee MS, Harris AD. Environmental contamination because of
AC C
29.
multidrug-resistant Acinetobacter baumannii surrounding colonized or infected patients. Am J Infect Control 2011;39:711‒715. 30.
Djahmi N, Dunyach-Remy C, Pantel A, Dekhil M, SottoA, Lavigne JP. Epidemiology of carbapenemase-producing Enterobacteriaceae and Acinetobacter baumannii in Mediterranean countries. Biomed Res Int 2014;2014:305784.
31.
Yong D, Toleman MA, Giske CG, Cho HS, Sundman K, Lee K, Walsh TR. Characterization of a new metallo-beta-lactamase gene, bla(NDM-1), and a novel erythromycin esterase gene carried on a unique genetic structure in Klebsiella pneumoniae sequence type 14 from India. Antimicrob Agents Chemother 2009;53:5046‒5054.
32.
ACCEPTED MANUSCRIPT
Bakour S, Touati A, Bachiri T, et al. First report of 16S rRNA methylase ArmAproducing Acinetobacter baumannii and spread of metallo-β-lactamase NDM-1 in Algerian hospitals. J Infect Chemother 2014;20:696‒701.
33.
Yang J, Chen Y, Jia X, et al. Dissemination and characterization of NDM-1-producing Acinetobacter pittii in an intensive care unit in China. Clin Microbiol Infect 2012;18:506‒513. Tsakris A, Ikonomidis A, Poulou A, et al. Clusters of imipenem-resistant Acinetobacter
RI PT
34.
baumannii clones producing different carbapenemases in an intensive care unit. Clin Microbiol Infect 2008;14:588‒594. 35.
Ansaldi F, Canepa P, Bassetti M, et al. Sequential outbreaks of multidrug-resistant
SC
Acinetobacter baumannii in intensive care units of a tertiary referral hospital in Italy: combined molecular approach for epidemiological investigation. J Hosp Infect
36.
M AN U
2011;79:134‒140.
Sousa C, Silva L, Grosso F, Lopes J, Peixe L. Development of a FTIR-ATR based model for typing clinically relevant Acinetobacter baumannii clones belonging to ST98, ST103, ST208 and ST218. J Photochem Photobiol 2014;133:108‒114. Agodi A, Voulgari E, Barchitta M, et al. Spread of a carbapenem- and colistin-resistant Acinetobacter baumannii ST2 clonal strain causing outbreaks in two Sicilian hospitals.
EP
TE D
J Hosp Infect 2014;86:260‒266.
AC C
37.
Table I
RI PT
ACCEPTED MANUSCRIPT
Distribution of Acinetobacter baumannii strains recovered from environmental samples and carbapenemase-producing imipenem-resistant strains Total no. of
Year
Areas in which A. baumannii strains
No. of strains
were isolated
isolated
NDM-1
OXA-23
4
3
‒
4
3
‒
1
1
‒
1
1
‒
1
1
‒
Bedside
1
1
‒
Radiator
1
1
‒
Hand
1
1
‒
2
2
‒
Bed sheets
3
1
2
Faucet
1
1
‒
Bedside
1
1
‒
Washbasin
1
‒
1
Toilet flush
1
1
‒
3
‒
3
Bed sheets
2
1
1
Medical equipmentb
12
4
6
samples
Infectious
100
diseases
2011 Handlesa Bed sheets Bed rail Faucet
Medical
270
EP
TE D
Switch
2012 Handlesa
AC C
Sétif
Intensive care unit
108
2013 Handles
SC
Wards
M AN U
Hospital
a
No. of imipenem-resistant strains
ACCEPTED MANUSCRIPT
2
2
1
Medical equipment trolley
3
‒
3
Staff uniform
1
‒
1
1
1
‒
1
‒
1
1
‒
‒
8
‒
‒
1
‒
1
2
1
1
1
‒
1
1
‒
1
1
‒
1
1
‒
1
2
‒
2
Bed sheets
1
‒
1
Faucet
1
1
‒
1
‒
1
Medical equipmentb
1
‒
1
Medical equipment trolley
1
‒
1
Gallows
1
‒
1
Microwave
1
‒
1
RI PT
Bed rail
Switch Bench top Wheelchair
Infectious
Handles
diseases
Bed sheets
M AN U
a
Medical equipment trolley 250
2012 Faucet Gallows
Medical
60
80
2013 Handles
a
EP
Paediatric
TE D
Washbasin
2013 Handlesa
AC C
Béjaia
SC
Air
ACCEPTED MANUSCRIPT
868
67
RI PT
Total
ICU, intensive care unit. Handles of the doors, windows, and cupboards.
b
Stethoscope, heart rate monitor, urinary catheter, bubbler O2 machine with mask, syringe pump, respirator machine, aspiration probe,
SC
a
61
AC C
EP
TE D
M AN U
electrocardiogram.
ACCEPTED MANUSCRIPT
Table II
sampling Strains
Areas of A. baumannii strains
Wards
Year of isolation
isolated Bed rail
Infectious
2011
INF1G
Bed sheets
Infectious
2011
INF96P
Door handles
Infectious
INF87A
Bedside
INF46G INF50P
Carbapenemase
ST
genes OXA-51/OXA-23
ST19
>32
OXA-51/OXA-23
ST2
2011
>32
OXA-51/OXA-23
ST2
Infectious
2011
>32
OXA-51/OXA-23
ST2
Radiator
Infectious
2011
>32
OXA-51/OXA-23
ST2
Door handles
Infectious
2011
>32
OXA-51/OXA-23
ST11
TE D
INF50G
IMP MIC (mg/L)
>32
M AN U
INF16
Door handles
Bed sheets
INF5G
Bed sheets
660
2011
5 >32
OXA-51/OXA-23
ST11 5
Infectious
2011
>32
OXA-51/OXA-23
ST2
Infectious
2011
>32
OXA-51/OXA-23
ST19
Healthcare workers’ hands
Infectious
2011
>32
OXA-51/OXA-23
ST19
INF7
Faucet
Infectious
2011
>32
OXA-51/OXA-23
ST98
393
Switch
Infectious
2011
>32
OXA-51/OXA-23
ST2
MI31
Bedside
Medical
2012
>32
OXA-51/OXA-23
ST19
MI113
Door handles
Medical
2012
>32
OXA-51/OXA-23
ST2
MI88
Door handles
Medical
2012
>32
OXA-51/OXA-23
ST2
EP
INF95A
Infectious
AC C
Sétif
SC
Hospital
RI PT
Resistance genes carried by Acinetobacter baumannii isolates found during the study period, and sorted per hospital, ward, and year of
ACCEPTED MANUSCRIPT
Toilet flush
Medical
2012
>32
OXA-51/OXA-23
ST2
MI244
Bed sheets
Medical
2012
>32
OXA-51/OXA-23
ST2
MI116
Faucet
Medical
2012
>32
OXA-51/OXA-23
ST2
MI152G
Washbasin
Medical
2012
>32
OXA-51/NDM-1
ST85
MI27
Bed sheets
Medical
2012
>32
OXA-51/NDM-1
ST85
MI238
Bed sheets
Medical
2012
>32
OXA-51/NDM-1
ST85
SR03
Heart rate monitor
ICU
2013
>32
OXA-51/OXA-23
ST19
SR04
Bubbler of O2
ICU
2013
>32
OXA-51/OXA-23
ST19
SR08
Aspirator probe
ICU
2013
>32
OXA-51/OXA-23
ST19
SR34
Medical equipment trolley
ICU
2013
>32
OXA-51/OXA-23
ST19
SR37
Switch
ICU
2013
>32
OXA-51/OXA-23
ST19
SR38
Medical equipment trolley
ICU
2013
>32
OXA-51/OXA-23
ST19
SR48
Heart rate monitor
ICU
2013
>32
OXA-51/OXA-23
ST19
SR47B
Bed sheets
ICU
2013
>32
OXA-51/OXA-23
ST19
SR64
Heart rate monitor
ICU
2013
>32
OXA-51/OXA-23
ST19
SR02
Door handles
ICU
2013
>32
OXA-51/NDM-1
ST85
SR07
Bed rail
ICU
2013
>32
OXA-51/NDM-1
ST85
SR15
Bed rail
ICU
2013
>32
OXA-51/NDM-1
ST85
SR18
Heart rate monitor
ICU
2013
>32
OXA-51/NDM-1
ST85
SR20
Medical equipment trolley
ICU
2013
>32
OXA-51/NDM-1
ST85
SR22
Bed sheets
ICU
2013
>32
OXA-51/NDM-1
ST85
SR24
Door handles
ICU
2013
>32
OXA-51/NDM-1
ST85
SR26
Respirator machine
ICU
2013
>32
OXA-51/NDM-1
ST85
SC
M AN U
TE D EP
AC C
RI PT
MI121
ACCEPTED MANUSCRIPT
ICU
2013
>32
OXA-51/NDM-1
ST85
SR65
Window handles
ICU
2013
>32
OXA-51/NDM-1
ST85
SR50
Bed rail
ICU
2013
>32
OXA-51/NDM-1
ST85
SR84
Staff uniform
ICU
2013
>32
OXA-51/NDM-1
ST85
SR59
Bench top
ICU
2013
>32
OXA-51/NDM-1
ST85
SR39
Aspirator probe
ICU
2013
>32
OXA-51/NDM-1
ST85
SR49C
Urinary catheter
ICU
2013
>32
OXA-51/NDM-1
ST85
FP19
Washbasin
Infectious
2012
>32
OXA-51/NDM-1
ST85
FP121
Door handles
Infectious
2012
>32
OXA-51/NDM-1
ST85
FP95
Medical equipment trolley
Infectious
2012
>32
OXA-51/NDM-1
ST85
FP92
Bed sheets
Infectious
2012
>32
OXA-51/NDM-1
ST85
FP120
Faucet
Infectious
2012
>32
OXA-51/NDM-1
ST85
FFX
Gallows
Infectious
2012
>32
OXA-51/NDM-1
ST85
FI76
Bed sheets
Infectious
2012
>32
OXA-51/OXA-23
ST2
AP19
Faucet
Paediatric
2013
>32
OXA-51/OXA-23
ST2
AP16
Door handles
Paediatric
2013
>32
OXA-51/NDM-1
ST85
AP54
Cupboard handles
Paediatric
2013
>32
OXA-51/NDM-1
ST85
AP48
Bed sheets
Paediatric
2013
>32
OXA-51/NDM-1
ST85
AMF32
Medical equipment trolley
Medical
2013
>32
OXA-51/NDM-1
ST85
AMF37
Electrocardiogram
Medical
2013
>32
OXA-51/NDM-1
ST85
AM36
Microwave
Medical
2013
>32
OXA-51/NDM-1
ST85
AMF27
Cupboard handles
Medical
2013
>32
OXA-51/NDM-1
ST85
EP
TE D
M AN U
SC
RI PT
Syringe pump
AC C
Béjaia
SR35A
ACCEPTED MANUSCRIPT
AMF16A
Gallows
Medical
2013
>32
OXA-51/NDM-1
ST85
RI PT
IMP, imipenem; MIC, minimum inhibitory concentration; ST, sequence type; ICU, intensive care unit.
Figure 1. Antimicrobial susceptibility of 67 Acinetobacter baumannii isolates from hospital environments. TIC, ticarcillin; PRL, piperacillin; ATM, aztreonam; CAZ, ceftazidime; TIM, ticarcillin–clavulanic acid; CIP, ciprofloxacin; TZP, piperacillin–tazobactam; IPM, imipenem; SXT,
AC C
EP
TE D
M AN U
SC
cotrimoxazol; CN, gentamicin; TOB, tobramycin; TGC, tigecyclin; AK, amikacin; K, kanamycin; RA, rifampin; CT, colistin.
ACCEPTED MANUSCRIPT
RI PT
100 90
70
SC
60 50
M AN U
40 30 20 10 0 PRL
ATM
CAZ
TIM
CIP
TPZ
TE D
TIC
IPM
SXT
CN
TOB
TGC
AK
K
RA
EP
Figure 1. Antimicrobial susceptibility of 67 A. baumannii isolated from hospital environment Ticarcillin (TIC), ticarcillin–clavulanic acid (TIM), piperacillin (PRL), piperacillin–tazobactam (TZP), ceftazidime (CAZ), imipenem (IPM), aztreonam (ATM), amikacin (AK), tobramycin (TOB), kanamycin (K), gentamicin (CN), ciprofloxacin (CIP), tigecyclin (TGC), cotrimoxazol (SXT), rifampin (RA), and colistin (CT).
AC C
Resistance (%)
80
CT
S0195-6701(15)00398-9
DOI:
10.1016/j.jhin.2015.09.020
Reference:
YJHIN 4658
To appear in:
Journal of Hospital Infection
Received Date: 7 July 2015 Accepted Date: 28 September 2015
Please cite this article as: Zenati K, Touati A, Bakour S, Sahli F, Rolain JM, Characterization of NDM-1- and OXA-23-producing Acinetobacter baumannii isolates from inanimate surfaces in a hospital environment in Algeria, Journal of Hospital Infection (2015), doi: 10.1016/j.jhin.2015.09.020. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
K. Zenati et al.
Characterization of NDM-1- and OXA-23-producing Acinetobacter baumannii isolates from inanimate surfaces in a hospital environment in Algeria K. Zenatia,b, A. Touatib, S. Bakoura,b, F. Sahlic, J.M. Rolaina,* a
Unité de recherche sur les maladies infectieuses et tropicales émergentes (URMITE), UM 63,
CNRS 7278, IRD 198, INSERM 1095, IHU Méditerranée Infection, Faculté de Médecine et de b c
RI PT
Pharmacie, Aix-Marseille-Université, Marseille, France
Laboratoire d’Ecologie Microbienne, FSNV, Université de Bejaia, 06000 Bejaia, Algeria
Laboratoire de Microbiologie, CHU de Sétif, Algeria
______________________ *
SC
Corresponding author. Address: IHU Méditérranée Infectiopole Sud, URMITE, 27
Boulevard Jean Moulin, Marseille, 13010, France. Tel.: +33 4 91 32 43 75; fax: +33 4 91 38
M AN U
77 72.
AC C
EP
TE D
E-mail address: [email protected] (J.M. Rolain).
1
ACCEPTED MANUSCRIPT
SUMMARY
Background: Investigation of several outbreaks of multidrug-resistant Acinetobacter baumannii infection has demonstrated that contamination of the inanimate hospital environment could be implicated in the spread of these multidrug-resistant strains. Aim: To investigate the occurrence of carbapenem-resistant A. baumannii on inanimate surfaces and possible dissemination in the hospital environment in Algeria as a potential
RI PT
source of infection in humans.
Methods: A. baumannii strains were isolated from the hospital environment and identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility was determined using disc diffusion and E-test methods.
SC
Carbapenemase activity was detected using microbiological tests, including modified Hodge test, modified Carba NP test, and EDTA test. Carbapenem resistance determinants were
M AN U
studied by polymerase chain reaction (PCR) and sequencing. Clonal relatedness was determined using multi-locus sequence typing (MLST).
Results: A total of 67 A. baumannii isolates were obtained from 868 environmental samples and identified by MALDI-TOF MS. Among them, 61 isolates were resistant to imipenem with minimum inhibitory concentration >32 µg/mL and positive by the modified Hodge test and modified Carba NP test. In addition, the activity of carbapenemase was inhibited by
TE D
EDTA in 32 strains. PCR and sequencing showed the presence of blaOXA-23 gene in 29 strains, and the blaNDM-1 gene in 32 isolates. MLST demonstrated the presence of five types of ST (ST19, ST2, ST85, ST98, and ST115).
Conclusion: Our study demonstrated the dissemination of carbapenemase-producing A.
EP
baumannii strains recovered from inanimate surfaces in a hospital environment, surrounding patients, healthcare workers and visitors, in Algeria as a potential source for nosocomial
AC C
infection. Keywords:
Acinetobacter baumannii Carbapenemases
Hospital environment NDM-1 Nosocomial infection OXA-23 Introduction
Hospital surfaces play an important role in nosocomial infections. The healthcare environment contains a diverse population of micro-organisms and can serve as reservoirs of
ACCEPTED MANUSCRIPT
potential pathogens.1 Acinetobacter baumannii has emerged as an important infectious agent in hospitalized patients worldwide and especially in developing countries.2 In general, the success of A. baumannii can be attributed to: (i) its ability to form biofilms and resist desiccation on abiotic surfaces (i.e. medical devices and environmental surfaces); (ii) its ability to adhere, to colonize and to invade human epithelial cells; (iii) its repertoire of antibiotic resistance mechanisms that are able to be promptly up-regulated as required; and
RI PT
(iv) its ability to acquire foreign genetic material through lateral gene transfer to promote its own survival under antibiotic and host selection pressures.3 Investigation of several outbreaks of multidrug-resistant A. baumannii infection has demonstrated that the contamination of the inanimate hospital environment could be implicated in the spread of these multidrug-resistant
SC
strains.2,4,5 The most frequent means of transmission occurs via hands of health professionals, patients, contaminated hospital surfaces, and medical equipment.6,7
M AN U
The emergence of carbapenem resistance in A. baumannii has become a significant public health concern. Three types of enzyme capable of hydrolysing carbapenems have been reported in A. baumannii: (i) β-lactamases inhibited by clavulanic acid (Ambler class A) such as KPC-2 and GES-14; (ii) metallo-β-lactamases (Ambler class B) such as IMP-1, VIM-2, SIM-1, and NDM-1; and (iii) Ambler class D β-lactamases, which are referred to as oxacillinases such as OXA-23, OXA-24 and OXA-58.8 Carbapenem resistance in A.
TE D
baumannii is mostly associated with OXA-type β-lactamases, especially OXA-23, which have a higher dissemination worldwide and have also been reported from African countries, but NDM-1-like enzymes have been increasingly reported.9,10 Outbreaks of carbapenemase-producing A. baumannii strains isolated from the
EP
hospital environment have been documented in diverse geographical areas including Europe, Asia, and the Middle East.2,5,11,12 In Algeria, the dissemination of carbapenemases, such as the
AC C
blaOXA-23-like, blaOXA-24-like, blaOXA-58-like and blaNDM-1 genes among A. baumannii isolated from clinical samples, has been reported in previous studies but there is currently little information on the dissemination of theses carbapenemases into the hospital environment in Algeria.13‒15 Touati et al. have reported in a previous study the characterization of extended-spectrum βlactamase-producing Enterobacteriaceae strains isolated from a hospital environment in Bejaia (Algeria).16,17 In addition, imipenem-resistant A. baumannii isolated from inanimate surfaces was reported by Mesli et al. in western Algeria.14 The aim of our present study was to characterize the molecular epidemiology and mechanisms of carbapenem resistance of A. baumannii isolated from the inanimate surfaces of the hospital environment in two university hospitals in Algeria (Sétif and Bejaia). Methods
ACCEPTED MANUSCRIPT
Study design
The study was performed from January 2011 to March 2013 in the 900-bed Sétif teaching hospital and the 425-bed Bejaia teaching hospital. The hospitals contain both medical and chirurgical wards. A total of 868 environmental samples were obtained while the patient and healthcare personnel occupied the room and from adjacent equipment of four wards including intensive
RI PT
care unit (ICU), infectious diseases, medical, and paediatric wards from the two hospitals. Different samples were collected from several frequently contacted surfaces. Bacterial isolates
At each site, an area of ~25 cm2 was sampled using a sterile cotton swab previously
SC
moistened with Nutrient Broth Medium.18 Swabs for each surface type were cultured in the Nutrient Broth Medium and incubated at 37°C for 24 to 48 h. The strains were isolated on
M AN U
MacConkey agar plates containing ceftazidime (4 mg/L). They were first identified by conventional methods (Gram stains and biochemical tests) and confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).19 Antimicrobial susceptibility
Antibiotic susceptibility was determined on the Mueller‒Hinton agar using the standard disc diffusion procedure as recommended by the European Committee on
TE D
Antimicrobial Susceptibility Testing (EUCAST).20 Sixteen antibiotics were tested, including ticarcillin, ticarcillin–clavulanate, piperacillin, piperacillin–tazobactam, ceftazidime, imipenem, aztreonam, amikacin, tobramycin, kanamycin, gentamicin, ciprofloxacin, tigecyclin, cotrimoxazol, rifampin, and colistin (Bio-Rad, Hercules, CA, USA). Minimum
EP
inhibitory concentrations (MICs) of imipenem were determined using the E-test method (AB Biodisk, Solna, Sweden). The results were interpreted according to the recommendations of
AC C
EUCAST.20
β-Lactamase assays
The modified Hodge test and the modified Carba NP test were used to confirm the
carbapenemase production as described by Bakour et al.21 Metallo-β-lactamase was detected by EDTA-disc synergy test as previously described.22 Molecular analysis Genotypic detection of carbapenemase-encoding genes was carried out by real-time and standard polymerase chain reaction (PCR) targeting blaOXA-23, blaOXA-24, blaOXA-58, blaOXA-51, and blaNDM-1 genes in all A. baumannii strains as described previously.23 Molecular epidemiology
ACCEPTED MANUSCRIPT
Multi-locus sequencing typing (MLST) was performed using seven conserved housekeeping genes (cpn60, fusA, gltA, pyrG, recA, rplB, and rpoB) according to Pasteur schemes available at the Institute Pasteur MLST web site (www.pasteur.fr/mlst). DNA sequencing PCR products were purified and sequenced using Big Dye terminator chemistry on an ABI 3730 automated sequencer (Applied Biosystems, Foster City, CA, USA). The sequences
RI PT
obtained were analysed using BlastN and BlastP against the NCBI database (www.ncbi.nlm.nih.gov). Results Bacterial strains
SC
Sixty-seven A. baumannii isolates were taken from the 868 environmental samples (7.7%) and identified as A. baumannii both by conventional methods and by MALDI-TOF
M AN U
MS and confirmed by the presence of the blaOXA-51-like gene in all of the isolates. Fifty-one A. baumannii strains were isolated from Sétif hospital and 16 strains from Bejaia hospital. The isolates were recovered mainly from handles (13/67), bed sheets (12/67), medical equipment (13/67), medical equipment trolleys (5/67), and from bed rails (4/67). The distribution of the cultures from environmental samples and the number of bacteria isolated are shown in Table I.
TE D
Antimicrobial susceptibility
Antibiotic susceptibility testing revealed that the isolates showed a high resistance to almost all antibiotics tested, including β-lactams, aminoglycosides, and fluoroquinolones (Figure 1). Among the 67 A. baumannii isolates, 61 showed high-level resistance to
EP
carbapenems (91%) with high imipenem minimum inhibitory concentration (>32 mg/L) (Table II). Colistin and rifampin showed efficacy against all strains except one strain that was
AC C
resistant to rifampin. The modified Hodge test and the modified Carba NP test were positive for all imipenem-resistant A. baumannii isolates, whereas β-lactamase activity was inhibited by EDTA for 32 A. baumannii isolates. Resistance-gene determination PCR detected the presence of genes encoding blaOXA-23 in 29 isolates (27 from Sétif
and two from Bejaia), and blaNDM-1 in 32 isolates (18 from Sétif and 14 from Bejaia) (Table II). The blaOXA-23 gene was isolated only in an infectious diseases ward in Sétif hospital compared with the same wards in Bejaia hospital, and the blaNDM-1 gene was isolated only in the medical ward in Bejaia hospital compared with the same wards in Sétif hospital (Table II). MLST
ACCEPTED MANUSCRIPT
The clonal relationship of isolates analysed by MLST showed diversity in the sequences found. Five sequence types (ST19, ST2, ST85, ST98, and ST115) were found in Sétif hospital, whereas only two (ST2 and ST85) were found in Bejaia hospital (Table II). All strains of A. baumannii producing metallo-β-lactamase enzyme NDM-1 belonged to ST85. Unlike ST19 and ST2, types ST98 and ST115 were observed in strains producing OXA-23 (Table II).
RI PT
Discussion
The hospital environment provides an important ecological niche for micro-organisms that could have clinical significance.24 It is thought that A. baumannii strains found in the environment may be a source for contamination and spread among patients.25 The present
and equipment within two Algerian hospitals.
SC
study showed significant colonization of A. baumannii isolates on different inanimate surfaces
M AN U
A. baumannii strains may survive in humid environments, such as ventilator devices in hospitals, and also in dry conditions for extended periods and thus facilitate transmission between patients and healthcare workers.25,26 Contamination of the environment surrounding patients such as handles, bed sheets, bed rails, bedside, hands of the healthcare workers, and medication trolleys and equipment have been reported previously in the literature, and therefore the environment was considered as the main source of A. baumannii transmission
TE D
and of several outbreaks.2,5,11 Primary transmission of pathogens on to surfaces originates from hands, patients, hospital water systems, and airborne sources.26 In published data about A. baumannii outbreaks, patient environment, medical equipment or healthcare workers were reported to be colonized. In a study from Turkey, an outbreak in a neonatal ICU revealed that
EP
contamination was particularly evident on intubation devices and suction tools. The pulsedfield gel electrophoresis study showed that the strains from devices, healthcare workers’
AC C
hands, and clinical samples were the same clone.27 In Taiwan, microbial contamination of airborne and surface (medication trolley, bedrail, cabinet, respirator) suggested a higher relative risk among infected patients in the presence of the pathogens as compared to the absence of pathogens.28 Environmental contamination with multidrug-resistant A. baumannii assumes a greater importance when patients are managed in wards with shared facilities; the finding of bacterial contamination of near-patient surfaces and medical equipment could explain the results obtained in our study. Strains isolated in our study were found to be multidrug resistant. When we compared our results with published clinical imipenem-resistant A. baumannii isolates in Algeria, we observed the same high frequency of antibiotic-resistant strains on both hospital surfaces and clinical samples.13‒15 Markogiannakis et al. have reported A. baumannii clonal strains causing
ACCEPTED MANUSCRIPT
episodes of sepsis in a trauma ICU in Greece isolated from inanimate surfaces and healthcare workers, resistant to tobramycin, colistin, gentamicin, and meropenem.4 In our study, we found imipenem-resistant A. baumannii on the uniform and hands of staff, bench tops, trolleys, and medical equipment. These surfaces are often touched by healthcare workers during routine patient care and may act as a possible source of nosocomial prevent contact isolation of colonized and infected patients.11
RI PT
infection.29 This finding can be explained by insufficient handwashing and the inability to
Since 2009, the blaOXA-23 gene has become the most prevalent carbapenemase-
encoding gene circulating in the Mediterranean region.30 Global dissemination of the blaNDM-1 gene has been extensively described since its first report in K. pneumoniae in India.31
SC
Previous reports from Algeria have revealed that resistance to carbapenems in A. baumannii clinical isolates is mainly mediated by class D (oxacillinase) carbapenemases (OXA-23,
M AN U
OXA-24, OXA-58) and by class B (metallo-β-lactamase) carbapenemase NDM-1.13,14,15,32 However, environmental imipenem-resistant A. baumannii isolates from inanimate surfaces producing OXA-23 and OXA-24 have been reported only by Mesli et al. from west Algerian hospitals.14 In Jordan, multidrug-resistant A. baumannii strains producing OXA-23, OXA-24, and OXA-51 enzymes isolated in ICUs were reported in the hospital environment, especially in water and moist environments.2
TE D
Our study described 29 carbapenem-resistant A. baumannii isolates harbouring the blaOXA-23 gene and 32 isolates harbouring the blaNDM-1 gene besides blaOXA-51. Few MBL-producing Acinetobacter spp. have been identified from inanimate surfaces in hospital environments. NDM-1-producing Acinetobacter pittii was isolated from inanimate
EP
surfaces (equipment buttons, bed sheets, chairs, water taps, drawer handles, and air) in an ICU in China.33 VIM-producing A. baumannii (VIM-1 and VIM-4) were isolated from the floor,
AC C
beds and external sites of the ventilator tube in an ICU in Greece.34 To our knowledge, no report concerning the isolation of NDM-1-producing A. baumannii in Algerian hospitals environment has been published. This finding indicated that inanimate surface transmission might contribute to the
spread of carbapenem-resistant A. baumannii, which is in line with earlier studies on outbreaks of carbapenem-resistant Acinetobacter species, suggesting environmental transmission.4,33 The origin and spread of NDM-1-positive A. baumannii in this study remains unknown. NDM-producing A. baumannii were recovered from different wards in various samples (washbasins, bed sheets, faucets, medical equipment trolleys, microwaves) except in the infectious diseases ward from Sétif hospital. This finding can be explained by the fact that
ACCEPTED MANUSCRIPT
the first NDM-1-positive A. baumannii was isolated in 2012 from patient samples in the same ward in Sétif hospital by Bakour et al.32 Unlike our study, no NDM-1-positive A. baumannii was isolated from clinical samples in Bejaia hospital by the same authors in a later study.21 In Sétif hospital, the first carbapenemase genes detected in clinical A. baumannii were blaOXA-23 and blaOXA-72 genes in 2010 followed by blaNDM-1 in 2012.13,32 In Bejaia hospital, only blaOXA-23 has been reported since 2012. Today, the novelty in Algerian hospitals is the
RI PT
emergence and dissemination of blaNDM-1 from clinical samples to the hospital environment since 2012.
In our study, the carbapenemase-producing A. baumannii strains isolated from the hospital environment belong to ST85, ST2, ST19, ST98, and ST115. Previous studies
SC
reported that the A. baumannii strains isolated from Algerian patients belonged to ST1, ST2, ST19, ST25, ST85, and ST95.32
The study of the clonal typing revealed that the environmental strains have the same
M AN U
STs as the clinical strains previously reported: OXA-23 (ST2 and ST19), NDM-1 (ST85).32 However, new sequence types (ST98 and ST115) were reported for the first time in Algeria in Sétif hospital (infectious ward). The ST115 was reported in 2011 (one strain isolated in 2008) and the ST98 was reported in 2014 (25 strains isolated in 2009) in Italian and Portuguese hospitals respectively.35,36 These strains were certainly imported and persisted in the
TE D
environment without clinical incidence. These results confirm the clonal diversity among the A. baumannii clinical and environmental isolates in Algeria. In Mediterranean countries, including Algeria, the main clone isolated harbouring NDM-1-producing A. baumannii belonged to ST85; however, the ST2 belonged to the
EP
International clone II.30,37
In addition, the detection of common clones among environmental and clinical
AC C
imipenem-resistant isolates of A. baumannii suggests that environmental contamination might have contributed to the difficulty in restricting the spread of these organisms in the wards and hospitals. Environmental surveillance and strict antiseptic techniques may have contributed to the reduced spread of these bacteria.34 One limitation of this study was that we included only environmental isolates so that
comparison with clinical isolates was not performed. In conclusion, the presence of clonal isolates producing OXA-23 and NDM-1 enzymes in the hospital environment may act as a reservoir of resistance genes which can be transmitted horizontally to other isolates (clinical or environmental). In addition, it may be a risk factor for nosocomial outbreaks. This study highlights the complexity of the molecular epidemiology of A. baumannii in the hospital environment during non-outbreak periods.
ACCEPTED MANUSCRIPT
Education of environmental services and nursing staff, enhanced cleaning of frequently contaminated areas, and potentially routine screening of environmental surfaces to ensure adequate cleaning may help to limit the spread of multidrug-resistant strains in the hospital environment and reduce the risk of an epidemic. Acknowledgement We thank L. Hadjadj for technical assistance.
RI PT
Conflict of interest statement None declared. Funding source
This work was partly funded by CNRS and IHU Méditerranée Infection.
1.
SC
References
Jalalpoor S. Study of the antibiotic resistance pattern among the bacteria isolated from
2011;5:3317‒3320. 2.
M AN U
the hospital environment of Azzahra Hospital, Isfahan, Iran. Afr J Microbiol Res
Obeidat N, Jawdat F, Al-Bakri AG. Major biologic characteristics of Acinetobacter baumannii isolates from hospital environmental and patient’s respiratory tract sources. Am J Infect Control 2014;42:40140‒40144.
3.
Cerqueira GM, Peleg AY. Insights into Acinetobacter baumannii pathogenicity. IUBMB
4.
TE D
Life 2011;63:1055‒1060.
Markogiannakis A, Fildisis G, Tsiplakou S, et al. Cross-transmission of multidrugresistant Acinetobacter baumannii clonal strains causing episodes of sepsis in a trauma intensive care unit. Infect Control Hosp Epidemiol 2008;29:410‒417. Bourigault C, Corvec S, Bretonnière C, et al. Investigation and management of
EP
5.
multidrug-resistant Acinetobacter baumannii spread in a French medical intensive care
6.
AC C
unit: one outbreak may hide another. Am J Infect Control 2013;41:652‒655. Oliveira AC, Damasceno QS. Surfaces of the hospital environment as possible deposits of resistant bacteria: a review. Rev Esc Enferm USP 2010;44:1112‒1117. 7.
Weber DJ, Rutala WA. Understanding and preventing transmission of healthcare associated pathogens due to the contaminated hospital environment. Infect Control and Hosp Epidemiol 2013;34:450‒452.
8.
Kempf M, Rolain JM. Emergence of resistance to carbapenems in Acinetobacter baumannii in Europe: clinical impact and therapeutic options. Int J Antimicrob Agents 2012;39:105‒119.
9.
ACCEPTED MANUSCRIPT
Jones LS, Toleman MA, Weeks JL, Howe RA, Walsh TR, Kumarasamy KK. Plasmid carriage of blaNDM-1 in clinical Acinetobacter baumannii isolates from India. Antimicrob Agents Chemother 2014;58:4211‒4213.
10.
Revathi G, Siu LK, Po-Liang, Huang LY. First report of NDM-1-producing Acinetobacter baumannii in East Africa. Int J Infect Dis 2013;17:1255‒1258.
11.
Aygün G, Demirkiran O, Utku T, et al. Environmental contamination during
RI PT
carbapenem resistant Acinetobacter baumannii outbreak in an intensive care unit. J Hosp Infect 2002;52:259‒262. 12.
Zhang R, Hu YY, Yang XF, et al. Emergence of NDM-producing non-baumannii Acinetobacter spp. isolated from China. Eur J Clin Microbiol Infect Dis
13.
SC
2014;33:853‒860.
Bakour S, Kempf M, Touati A, et al. Carbapenemase-producing Acinetobacter
14.
M AN U
baumannii in two university hospitals in Algeria. J Med Microbiol 2012;61:1341‒1343. Mesli E, Berrazeg M, Drissi M, Bekkhoucha SN, Rolain JM. Prevalence of carbapenemase-encoding genes including New Delhi metallo-beta-lactamase in Acinetobacter species, Algeria. Int J Infect Dis 2013;17:739‒743. 15.
Touati M, Diene SM, Racherache A, Dekhil M, Djahoudi A, Rolain JM. Emergence of blaOXA-23 and blaOXA-58 carbapenemase-encoding genes in multidrug-resistant
TE D
Acinetobacter baumannii isolates from University Hospital of Annaba, Algeria. Int J Antimicrob Agents 2012;40:89‒91. 16.
Touati A, Benallaoua S, Djoudi F, Madoux J, Brasme L, De Champs C. Characterization of CTX-M-15-producing Klebsiella pneumoniae and Escherichia coli
EP
strains isolated from hospital environments in Algeria. Microb Drug Resist 2007;13:85‒89.
Touati A, Zenati K, Brasme L, Benallaoua S, De Champs C. Extended-spectrum β-
AC C
17.
lactamase characterisation and heavy metal resistance of Enterobacteriaceae strains isolated from hospital environmental surfaces. J Hosp Infect 2010;75:78‒79. 18.
French GL, Otter JA, Shannon KP, Adams NMT, Watling D, Parks MJ. Tackling contamination of the hospital environment by methicillin-resistant Staphylococcus aureus (MRSA): a comparison between conventional terminal cleaning and hydrogen peroxide vapour decontamination. J Hosp Infect 2004;57:31‒37.
19.
Seng P, Drancourt M, Gouriet F, et al. Ongoing revolution in bacteriology: routine identification of bacteria by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Clin Infect Dis 2009;49:543‒551.
20.
ACCEPTED MANUSCRIPT
European Committee on Antimicrobial Susceptibility Testing. Breakpoint tables for interpretation of MICs and zone diameters. Version 1.0. EUCAST; 2014. http://www.eucast.org.
21.
Bakour S, Olaitan AO, Ammari H, et al. Emergence of colistin- and carbapenemresistant Acinetobacter baumannii ST2 clinical isolates in Algeria: first case report. Microb Drug Resist 2015;21:279‒285. Jeong SH, Bae IK, Park KO, et al. Outbreaks of imipenem-resistant Acinetobacter
RI PT
22.
baumannii producing carbapenemases in Korea. J Microbiol 2006;44:423‒431. 23.
Mendes RE, Kiyota KA, Monteiro J, et al. Rapid detection and identification of metallobeta-lactamase-encoding genes by multiplex real-time PCR assay and melt curve
24.
SC
analysis. J Clin Microbiol 2007;45:544‒561.
Dancer SJ, Coyne M, Robertson C, Thomson A, Guleri A, Alcock A. Antibiotic use is
Infect 2006;62:200‒206. 25.
M AN U
associated with resistance of environmental organisms in a teaching hospital. J Hosp
Kirkgöz E, Zer Y. Clonal comparison of Acinetobacter strains isolated from intensive care patients and the intensive care unit environment. Turk J Med Sci 2014;44:643‒648.
26.
Cahill OJ, Claro T, O’Connor N, et al. Cold air plasma to decontaminate inanimate surfaces of the hospital environment. Appl Environ Microbiol 2014;80:2004‒2010. Hosoglu S, Hascuhadar M, Yasar E, Uslu S, Aldudak B. Control of an Acinetobacter
TE D
27.
baumannii outbreak in a neonatal ICU without suspension of service: a devastating outbreak in Diyarbakir, Turkey. Infection 2012;40:11‒18. 28.
Huang PY, Shi ZY, Chen CH, Den W, Huang HM, Tsai JJ. Airborne and surface-bound
EP
microbial contamination in two intensive care units of a medical center in central Taiwan. Aerosol Air Qual Res 2013;13:1060‒1069. Thom KA, Johnson K, Lee MS, Harris AD. Environmental contamination because of
AC C
29.
multidrug-resistant Acinetobacter baumannii surrounding colonized or infected patients. Am J Infect Control 2011;39:711‒715. 30.
Djahmi N, Dunyach-Remy C, Pantel A, Dekhil M, SottoA, Lavigne JP. Epidemiology of carbapenemase-producing Enterobacteriaceae and Acinetobacter baumannii in Mediterranean countries. Biomed Res Int 2014;2014:305784.
31.
Yong D, Toleman MA, Giske CG, Cho HS, Sundman K, Lee K, Walsh TR. Characterization of a new metallo-beta-lactamase gene, bla(NDM-1), and a novel erythromycin esterase gene carried on a unique genetic structure in Klebsiella pneumoniae sequence type 14 from India. Antimicrob Agents Chemother 2009;53:5046‒5054.
32.
ACCEPTED MANUSCRIPT
Bakour S, Touati A, Bachiri T, et al. First report of 16S rRNA methylase ArmAproducing Acinetobacter baumannii and spread of metallo-β-lactamase NDM-1 in Algerian hospitals. J Infect Chemother 2014;20:696‒701.
33.
Yang J, Chen Y, Jia X, et al. Dissemination and characterization of NDM-1-producing Acinetobacter pittii in an intensive care unit in China. Clin Microbiol Infect 2012;18:506‒513. Tsakris A, Ikonomidis A, Poulou A, et al. Clusters of imipenem-resistant Acinetobacter
RI PT
34.
baumannii clones producing different carbapenemases in an intensive care unit. Clin Microbiol Infect 2008;14:588‒594. 35.
Ansaldi F, Canepa P, Bassetti M, et al. Sequential outbreaks of multidrug-resistant
SC
Acinetobacter baumannii in intensive care units of a tertiary referral hospital in Italy: combined molecular approach for epidemiological investigation. J Hosp Infect
36.
M AN U
2011;79:134‒140.
Sousa C, Silva L, Grosso F, Lopes J, Peixe L. Development of a FTIR-ATR based model for typing clinically relevant Acinetobacter baumannii clones belonging to ST98, ST103, ST208 and ST218. J Photochem Photobiol 2014;133:108‒114. Agodi A, Voulgari E, Barchitta M, et al. Spread of a carbapenem- and colistin-resistant Acinetobacter baumannii ST2 clonal strain causing outbreaks in two Sicilian hospitals.
EP
TE D
J Hosp Infect 2014;86:260‒266.
AC C
37.
Table I
RI PT
ACCEPTED MANUSCRIPT
Distribution of Acinetobacter baumannii strains recovered from environmental samples and carbapenemase-producing imipenem-resistant strains Total no. of
Year
Areas in which A. baumannii strains
No. of strains
were isolated
isolated
NDM-1
OXA-23
4
3
‒
4
3
‒
1
1
‒
1
1
‒
1
1
‒
Bedside
1
1
‒
Radiator
1
1
‒
Hand
1
1
‒
2
2
‒
Bed sheets
3
1
2
Faucet
1
1
‒
Bedside
1
1
‒
Washbasin
1
‒
1
Toilet flush
1
1
‒
3
‒
3
Bed sheets
2
1
1
Medical equipmentb
12
4
6
samples
Infectious
100
diseases
2011 Handlesa Bed sheets Bed rail Faucet
Medical
270
EP
TE D
Switch
2012 Handlesa
AC C
Sétif
Intensive care unit
108
2013 Handles
SC
Wards
M AN U
Hospital
a
No. of imipenem-resistant strains
ACCEPTED MANUSCRIPT
2
2
1
Medical equipment trolley
3
‒
3
Staff uniform
1
‒
1
1
1
‒
1
‒
1
1
‒
‒
8
‒
‒
1
‒
1
2
1
1
1
‒
1
1
‒
1
1
‒
1
1
‒
1
2
‒
2
Bed sheets
1
‒
1
Faucet
1
1
‒
1
‒
1
Medical equipmentb
1
‒
1
Medical equipment trolley
1
‒
1
Gallows
1
‒
1
Microwave
1
‒
1
RI PT
Bed rail
Switch Bench top Wheelchair
Infectious
Handles
diseases
Bed sheets
M AN U
a
Medical equipment trolley 250
2012 Faucet Gallows
Medical
60
80
2013 Handles
a
EP
Paediatric
TE D
Washbasin
2013 Handlesa
AC C
Béjaia
SC
Air
ACCEPTED MANUSCRIPT
868
67
RI PT
Total
ICU, intensive care unit. Handles of the doors, windows, and cupboards.
b
Stethoscope, heart rate monitor, urinary catheter, bubbler O2 machine with mask, syringe pump, respirator machine, aspiration probe,
SC
a
61
AC C
EP
TE D
M AN U
electrocardiogram.
ACCEPTED MANUSCRIPT
Table II
sampling Strains
Areas of A. baumannii strains
Wards
Year of isolation
isolated Bed rail
Infectious
2011
INF1G
Bed sheets
Infectious
2011
INF96P
Door handles
Infectious
INF87A
Bedside
INF46G INF50P
Carbapenemase
ST
genes OXA-51/OXA-23
ST19
>32
OXA-51/OXA-23
ST2
2011
>32
OXA-51/OXA-23
ST2
Infectious
2011
>32
OXA-51/OXA-23
ST2
Radiator
Infectious
2011
>32
OXA-51/OXA-23
ST2
Door handles
Infectious
2011
>32
OXA-51/OXA-23
ST11
TE D
INF50G
IMP MIC (mg/L)
>32
M AN U
INF16
Door handles
Bed sheets
INF5G
Bed sheets
660
2011
5 >32
OXA-51/OXA-23
ST11 5
Infectious
2011
>32
OXA-51/OXA-23
ST2
Infectious
2011
>32
OXA-51/OXA-23
ST19
Healthcare workers’ hands
Infectious
2011
>32
OXA-51/OXA-23
ST19
INF7
Faucet
Infectious
2011
>32
OXA-51/OXA-23
ST98
393
Switch
Infectious
2011
>32
OXA-51/OXA-23
ST2
MI31
Bedside
Medical
2012
>32
OXA-51/OXA-23
ST19
MI113
Door handles
Medical
2012
>32
OXA-51/OXA-23
ST2
MI88
Door handles
Medical
2012
>32
OXA-51/OXA-23
ST2
EP
INF95A
Infectious
AC C
Sétif
SC
Hospital
RI PT
Resistance genes carried by Acinetobacter baumannii isolates found during the study period, and sorted per hospital, ward, and year of
ACCEPTED MANUSCRIPT
Toilet flush
Medical
2012
>32
OXA-51/OXA-23
ST2
MI244
Bed sheets
Medical
2012
>32
OXA-51/OXA-23
ST2
MI116
Faucet
Medical
2012
>32
OXA-51/OXA-23
ST2
MI152G
Washbasin
Medical
2012
>32
OXA-51/NDM-1
ST85
MI27
Bed sheets
Medical
2012
>32
OXA-51/NDM-1
ST85
MI238
Bed sheets
Medical
2012
>32
OXA-51/NDM-1
ST85
SR03
Heart rate monitor
ICU
2013
>32
OXA-51/OXA-23
ST19
SR04
Bubbler of O2
ICU
2013
>32
OXA-51/OXA-23
ST19
SR08
Aspirator probe
ICU
2013
>32
OXA-51/OXA-23
ST19
SR34
Medical equipment trolley
ICU
2013
>32
OXA-51/OXA-23
ST19
SR37
Switch
ICU
2013
>32
OXA-51/OXA-23
ST19
SR38
Medical equipment trolley
ICU
2013
>32
OXA-51/OXA-23
ST19
SR48
Heart rate monitor
ICU
2013
>32
OXA-51/OXA-23
ST19
SR47B
Bed sheets
ICU
2013
>32
OXA-51/OXA-23
ST19
SR64
Heart rate monitor
ICU
2013
>32
OXA-51/OXA-23
ST19
SR02
Door handles
ICU
2013
>32
OXA-51/NDM-1
ST85
SR07
Bed rail
ICU
2013
>32
OXA-51/NDM-1
ST85
SR15
Bed rail
ICU
2013
>32
OXA-51/NDM-1
ST85
SR18
Heart rate monitor
ICU
2013
>32
OXA-51/NDM-1
ST85
SR20
Medical equipment trolley
ICU
2013
>32
OXA-51/NDM-1
ST85
SR22
Bed sheets
ICU
2013
>32
OXA-51/NDM-1
ST85
SR24
Door handles
ICU
2013
>32
OXA-51/NDM-1
ST85
SR26
Respirator machine
ICU
2013
>32
OXA-51/NDM-1
ST85
SC
M AN U
TE D EP
AC C
RI PT
MI121
ACCEPTED MANUSCRIPT
ICU
2013
>32
OXA-51/NDM-1
ST85
SR65
Window handles
ICU
2013
>32
OXA-51/NDM-1
ST85
SR50
Bed rail
ICU
2013
>32
OXA-51/NDM-1
ST85
SR84
Staff uniform
ICU
2013
>32
OXA-51/NDM-1
ST85
SR59
Bench top
ICU
2013
>32
OXA-51/NDM-1
ST85
SR39
Aspirator probe
ICU
2013
>32
OXA-51/NDM-1
ST85
SR49C
Urinary catheter
ICU
2013
>32
OXA-51/NDM-1
ST85
FP19
Washbasin
Infectious
2012
>32
OXA-51/NDM-1
ST85
FP121
Door handles
Infectious
2012
>32
OXA-51/NDM-1
ST85
FP95
Medical equipment trolley
Infectious
2012
>32
OXA-51/NDM-1
ST85
FP92
Bed sheets
Infectious
2012
>32
OXA-51/NDM-1
ST85
FP120
Faucet
Infectious
2012
>32
OXA-51/NDM-1
ST85
FFX
Gallows
Infectious
2012
>32
OXA-51/NDM-1
ST85
FI76
Bed sheets
Infectious
2012
>32
OXA-51/OXA-23
ST2
AP19
Faucet
Paediatric
2013
>32
OXA-51/OXA-23
ST2
AP16
Door handles
Paediatric
2013
>32
OXA-51/NDM-1
ST85
AP54
Cupboard handles
Paediatric
2013
>32
OXA-51/NDM-1
ST85
AP48
Bed sheets
Paediatric
2013
>32
OXA-51/NDM-1
ST85
AMF32
Medical equipment trolley
Medical
2013
>32
OXA-51/NDM-1
ST85
AMF37
Electrocardiogram
Medical
2013
>32
OXA-51/NDM-1
ST85
AM36
Microwave
Medical
2013
>32
OXA-51/NDM-1
ST85
AMF27
Cupboard handles
Medical
2013
>32
OXA-51/NDM-1
ST85
EP
TE D
M AN U
SC
RI PT
Syringe pump
AC C
Béjaia
SR35A
ACCEPTED MANUSCRIPT
AMF16A
Gallows
Medical
2013
>32
OXA-51/NDM-1
ST85
RI PT
IMP, imipenem; MIC, minimum inhibitory concentration; ST, sequence type; ICU, intensive care unit.
Figure 1. Antimicrobial susceptibility of 67 Acinetobacter baumannii isolates from hospital environments. TIC, ticarcillin; PRL, piperacillin; ATM, aztreonam; CAZ, ceftazidime; TIM, ticarcillin–clavulanic acid; CIP, ciprofloxacin; TZP, piperacillin–tazobactam; IPM, imipenem; SXT,
AC C
EP
TE D
M AN U
SC
cotrimoxazol; CN, gentamicin; TOB, tobramycin; TGC, tigecyclin; AK, amikacin; K, kanamycin; RA, rifampin; CT, colistin.
ACCEPTED MANUSCRIPT
RI PT
100 90
70
SC
60 50
M AN U
40 30 20 10 0 PRL
ATM
CAZ
TIM
CIP
TPZ
TE D
TIC
IPM
SXT
CN
TOB
TGC
AK
K
RA
EP
Figure 1. Antimicrobial susceptibility of 67 A. baumannii isolated from hospital environment Ticarcillin (TIC), ticarcillin–clavulanic acid (TIM), piperacillin (PRL), piperacillin–tazobactam (TZP), ceftazidime (CAZ), imipenem (IPM), aztreonam (ATM), amikacin (AK), tobramycin (TOB), kanamycin (K), gentamicin (CN), ciprofloxacin (CIP), tigecyclin (TGC), cotrimoxazol (SXT), rifampin (RA), and colistin (CT).
AC C
Resistance (%)
80
CT