Occurrence of non-fermenting gram negative bacteria in drinking water dispensed from point-of-use microfiltration devices
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Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
Department of Education Sciences, University of Bologna, Italy
Ann Agric Environ Med. 2014;21(1):29–34
Introduction and objective. Many devices have been marketed in order to improve the organoleptic characteristics of tap water resulting from disinfection with chlorine derivates. The aim of the presented study was to assess the degree of contamination by non-fermenting Gram-negative bacteria (NF-GNB) of drinking water dispensed from microfiltration devices at point-of-use. Methods. Water samples were collected from 94 point-of-use water devices fitted with a filter (0.5μm pore size) containing powdered activated carbon. The microbiological contamination of water entering and leaving the microfiltered water dispensers was compared. The NF-GNB loads were correlated to Total Heterotrophic Counts (HPCs) at 37 and 22 °C, residua chlorine, and some structural and functional features of the devices. Results. NF-GNB were detected from 23% of supply water samples, 33% of still unchilled water, 33% of still chilled water and 18% of carbonated chilled water. The most frequent isolates were Pseudomonadaceae: Steno.maltophilia 30.2% of isolates, Pseudomonas 20.5%, Delftia acidovorans 13.4%, while the species more largely distributed was Ps. aeruginosa recovered from 13% of samples. The distribution of the various NF-GNB was different in the water entering and in that leaving the devices. Ps.aeruginosa and Steno.maltophilia were the predominant species in water leaving the microfiltration dispensers, probably due to their capacity to colonize the circuits and to prevail over the others. Recovery of NF-GNB was favoured by the reduction in residual chlorine of the supply water, occasional use, the absence of a bacteriostatic element in the filter and inadequate disinfection of the water lines. Conclusions. The presence of high concentrations of potentially pathogenic species of NF-GNB (Ps.aeruginosa, Steno. maltophilia, Burkhol.cepacia) in the water dispensed from microfiltration devices represents a risk of waterborne infections for vulnerable individuals. When these devices are used in environments such as hospitals, nursing homes for the elderly, etc., microbiological monitoring for the detection of NF-GNB is advisable.
Zanetti F, De Luca G, Sacchetti R. Control of bacterial contamination in microfiltered water dispensers (MWDs) by disinfection. Int J Food Microbiol. 2009; 128: 446–452.
Sacchetti R, De Luca G, Zanetti F. Influence of material and tube size on DUWL contamination in a pilot plant. New Microbiol. 2007; 30: 29–34.
Leoni E, Sacchetti R, Zanetti F, Legnani PP. Control of Legionella pneumophila contamination in a system for respiratory hydrotherapy with sulphurous spa water. Infect Control Hosp Epidemiol. 2006; 27(7): 716–721.
Szymanska J. Bacterial decontamination of DUWL biofilm using Oxigenal 6. Ann Agr Environ Med. 2006; 13: 163–167.
Wang JL, Chen ML, Lin YE, Chang SC, Chen YC. Association between contaminated faucets and colonization or infection by nonfermenting Gram-negative bacteria in intensive care units in Taiwan. J Clin Microbiol. 2009; 47(19): 3226–3230.
Leclerc H, Schwartzbrod L, Dei-Cas E. Microbial agents associated with waterborne diseases. Critical Rev Microbiol. 2002; 28: 371–409.
Stojek NM, Szymanska J, Dutkiewicz, J. Gram-negative bacteria in water distribution systems of hospitals. Ann Agr Environ Med. 2008; 15: 135–142.
Aydemir C, Aktas E, Eldes N, Kutsal E, Demirel F, Ege A. Community-acquired infection due to Stenotrophomonas maltophilia: a rare cause of septic arthritis. Turk J Pediatr. 2008; 50: 89–90.
Brooke JS. Stenotrophomonas maltophilia: an emerging global opportunistic pathogen. Clin Microbiol Rev. 2012; 25: 2–41.
Fihman V, Le Monnier A, Corvec S, Jaureguy F, Tankovic J, Jacquier H, et al. Stenotrophomonas maltophilia – the most worrisome treat among unusual non-fermentative gram-negative bacilli from hospitalized patients: a prospective multicenter study. J Infection. 2012; 64: 391–398.
Mahenthiralingam E, Baldwin A, Dowson CG. Burkholderia cepacia complex bacteria: opportunistic pathogens with important natural biology. J Appl Microbiol. 2008; 104: 1539–1551.
Zanetti F, De Luca G, Stampi S. Recovery of Burkholderia pseudomallei and B. cepacia from drinking water. Int J Food Microbiol. 2000; 59: 67–72.
Lee SM, Kim MK, Lee JL, Wee WR, Lee JH. Experience of Comamonas acidovorans keratitis with delayed onset and treatment response in immunocompromised cornea. Korean J Ophthalmol. 2008; 22: 49–52.
Stampi S, Zanetti F, Bergamaschi A, De Luca G. Comamonas acidovorans contamination of dental unit waters. Let Appl Microbiol. 1999; 29: 52–55.
Ryan MP, Pembroke JT, Adley CC. Ralstonia pickettii: a persistent gram-negative nosocomial infectiou organism. J Hosp Infect. 2006; 62: 278–284.
Yoshino Y, Kitazawa T, Kamimura M, Tatsuno K, Ota Y, Yotsuyanagi H. Pseudomonas putida bacteraemia in adult patients: five case reports and a review of the literature. J Infect Chemotherapy. 2011; 17: 278–282.
Sunbul M, Zivalioglu M, Tasdelen Fisgin N. Community-acquired Pseudomonas stutzeri meningitis in immunocompetent patient. Mikrobyol Bul. 2009; 43: 159–162.
Wong V, Levi K, Baddal B, Turton J, Boswell TC. Spread of Pseudomonas fluorescens due to contaminated drinking water in a bone marrow transplant unit. J Clin Microbiol, 2011; 49: 2093–2096.
Ceyhan M, Celik M. Elizabethkingia meningosepticum (Chryseo­bacterium meningosepticum) infections in children. Int J Ped. 2011; doi: 10.1155/2011/215237.
Shah S, Sarwar U, King EA, Lat A. Chryseobacterium indologenes subcutaneous port-related bacteraemia in a liver transplant patient. Transpl Infect Dis. 2012; 14: 398–402.
Martinez MA, OValle A. Weeksella virosa. Rev Chil Infectol. 2011; 28: 429–430.
Manckoundia P, Mazen E, Coste AS, Somana S, Marilier S, Duez JM, et al. A case of meningitis due to Achromobater xylosoxidans denitrificans 60 years after a cranial trauma. Med Sci Monitor. 2011; 17: 63–65.
Epling J. Bacterial conjuctivitis. Clin Evid. 2012.
Gupta N, Arora S, Kundra S. Moraxella catarrhalis as a respiratory pathogen. Ind J Path Microbiol. 2011; 54: 769–771.
Stojek NM, Dutkiewicz J. Legionella and other Gram-negative bacteria in potable water from various rural and urban sources. Ann Agr Environ Med. 2006; 13: 323–335.
Volker S, Schreiber C, Kistemann T. Drinking water quality in household supply infrastructure. A survey of the current situation in Germany. Int J Hyg Environ Health. 2010; 213: 204–209.
Chaberny IF, Kaiser P. Sonntag HG. Can soda fountains be recommended in hospitals? Int J Hyg Environ Health. 2006; 209: 471–475.
Baumgartner A, Grand M. Bacteriological quality of drinking water from dispensers (coolers) and possible control measures. J Food Prot. 2006; 69: 3043–3046.
Lévesque B, Simard P, Gauvin D, Gingras S, Dewailly E, Letarte R. Comparison of the microbiological quality of water coolers and that of municipal water systems. Appl Environ Microbiol. 1994; 60: 1174–1178.
Standard Methods for the Examination of Water and Wastewater. 21 th edn Washington, DC: APHA-AWWA-WEF, APHA 2005.
Mena KD, Gerba CP. Risk assessment of Pseudomonas aeruginosa in water. Rev Environ Contam Toxicol. 2009; 201: 71–115.
Guidelines for drinking water quality, fourth Ed. WHO, Geneva 2011.
Sacchetti R, De Luca G, Zanetti F. Control of Pseudomonas aeruginosa and Stenotrophomonas maltophilia contamination of microfiltered water dispensers with peracetic acid and hydrogen peroxide. Int J Food Microbiol. 2009; 132: 162–166.
Hansen CR. Stenotrophomonas maltophilia: to be or not to be a cystic fibrosis pathogen. Curr Opin Pulm Med. 2012; 18: 626–631.
Waters V, Atenafu EG, Salazar JG, Lu A, Yau Y, Matukas L et al. Chronic Stenotrophomonas maltophilia infection and exacerbation outcomes in cystic fibrosis. J Cyst Fibros. 2012, 11: 8–13.
D.Lgs 31/2001. Attuazione della Direttiva 98/83/CE relativa alle acque destinate al consumo umano. G.U. Repubblica Italiana. Supplemento n°52 del 3 marzo 2001.