A laboratory apparatus for the generation and biocide efficacy testing of Legionella biofilms

Green, P.N.; Pirrie, R.S.

doi:10.1111/j.1365-2672.1993.tb05143.x

Cited by 26 publications

(19 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…These studies have evaluated the effect of temperature and surface materials on the growth of L. pneumophila as well as the effect of biocides on sessile legionellae. The use of biofilm models to evaluate biocide efficacy against L. pneumophila represents a vast improvement over previous studies, which primarily evaluated the susceptibility of agar-grown bacteria in sterile water (120,174).…”

Section: Association With Biofilmsmentioning

confidence: 99%

Legionella and Legionnaires' Disease: 25 Years of Investigation

2002

View full text Add to dashboard Cite

There is still a low level of clinical awareness regarding Legionnaires' disease 25 years after it was first detected. The causative agents, legionellae, are freshwater bacteria with a fascinating ecology. These bacteria are intracellular pathogens of freshwater protozoa and utilize a similar mechanism to infect human phagocytic cells. There have been major advances in delineating the pathogenesis of legionellae through the identification of genes which allow the organism to bypass the endocytic pathways of both protozoan and human cells. Other bacteria that may share this novel infectious process are Coxiella burnetti and Brucella spp. More than 40 species and numerous serogroups of legionellae have been identified. Most diagnostic tests are directed at the species that causes most of the reported human cases of legionellosis, L. pneumophila serogroup 1. For this reason, information on the incidence of human respiratory disease attributable to other species and serogroups of legionellae is lacking. Improvements in diagnostic tests such as the urine antigen assay have inadvertently caused a decrease in the use of culture to detect infection, resulting in incomplete surveillance for legionellosis. Large, focal outbreaks of Legionnaires' disease continue to occur worldwide, and there is a critical need for surveillance for travel-related legionellosis in the United States. There is optimism that newly developed guidelines and water treatment practices can greatly reduce the incidence of this preventable illness

show abstract

Section: Association With Biofilmsmentioning

confidence: 99%

Legionella and Legionnaires' Disease: 25 Years of Investigation

2002

View full text Add to dashboard Cite

show abstract

“…Various oxidizing and non-oxidizing agents have been investigated for legionellae decontamination of water systems [2][3][4][5][6][19][20][21][22]. In this sense, CSHP and BNPD were examined as an example for oxidizing and non-oxidizing agents, respectively, in view of bactericidal action against different serogroups of L. pneumophila strains.…”

Section: Resultsmentioning

confidence: 99%

“…On the other hand, the others [21,23] indicated that BNPD was ineffective against legionellae. In our study, the efficacy of BNPD showed variability according to strains and contact times.…”

Section: Resultsmentioning

confidence: 99%

Efficacy of Colloidal Silver-Hydrogen Peroxide and 2-Bromo-2-nitroporopane-1,3-diol Compounds Against Different Serogroups of Legionella pneumophila Strains

et al. 2011

View full text Add to dashboard Cite

Cooling towers are considered as amplifier and disseminator sources for Legionella spp. despite preventive treatments. Information which was obtained from biocidal tests could improve the effectiveness of treatments. Therefore, the choice of appropriate biocides and the applying of biocides in correct dosages and contact times are important. Various oxidizing and non-oxidizing biocides have been investigated in vitro for their effectiveness against legionellae. Colloidal silver-hydrogen peroxide (CSHP) and 2-bromo-2-nitroporopane-1,3-diol (BNPD) biocides were selected as an example for oxidizing and non-oxidizing agents, respectively, in view of bactericidal action against different serogroups of L. pneumophila strains [serogroup 1 (S1) and serogroup 2-14 (S2)] which are isolated different cooling towers in the vicinity of Istanbul, Turkey and reference strain. In the current study, oxidizing biocide was found more effective than non-oxidizing biocide in terms of contact times, log reductions and recommended dosages. At the recommended concentrations for cooling towers (100 ppm), while CSHP compound killed all strains in 3 h contact time, BNPD compound killed S2 and reference strain in the same contact time, S1 strain after 6 h contact time. The results of the present study showed that effective biocide applications can be achieved by pre-determining minimum inhibitory concentration (MIC) and minimum contact time of different biocides to kill target bacteria.

show abstract

“…It has been suggested that the primary mode of dispersion of the etiological agent is an aerosol; inhalation of contaminated aerosols may result in outbreaks (Wright et al, 1991;Mcnally et al, 2000). In addition to aerosol forms, in manmade water systems, legionellae, like most other aquatic bacteria often exist as attached complex consortia (Green and Pirrie, 1993;Murga et al, 2001;Petti et al, 2004). Biofilms and sediments might create significant problems such as fouling (Johansen et al, 1997), heat transfer resistance (Wright et al, 1991), filter plugging (Laopaiboon et al, 2002) and metal corrosion (Momba and Binda, 2002), as well as increased resistance to antimicrobial compounds (Green and Pirrie, 1993;Surman et al, 1993;Viera et al, 1999;Kool, 2002) in water systems.…”

Section: Introductionmentioning

confidence: 99%

“…Therefore, in order to prevent legionellosis outbreaks, contaminated water systems must be disinfected and the most effective and practical biocide need to be evaluated (Elsmore, 1986). Various biocides have been examined for their efficacies in both laboratory simulations and field treatment of Legionella contaminations on cooling towers and in potable water systems (Skaliy et al, 1980;Grace et al, 1981;Elsmore, 1986;Yamamoto et al, 1991;Elsmore, 1993;Green and Pirrie, 1993;Surman et al, 1993;Lin et al, 1998;Viera et al, 1999;Walker et al, 1999;Gao et al, 2000;Donlan et al, 2002;Fields et al, 2002;Kim et al, 2002;Kool, 2002).…”

Section: Introductionmentioning

confidence: 99%

Efficacy of a quaternary ammonium compound against planktonic and sessile populations of differentLegionella pneumophila strains

2007

View full text Add to dashboard Cite

Efficacy of Gemacide PN-50 TM (a quaternary ammonium compound) as a commercial formulation recommended for disinfecting heat exchangers was determined for both planktonic and sessile populations of various Legionella pneumophila strains. The quaternary ammonium compound (QAC) was preferred as an alternative due to the emerging resistance of potentially pathogenic bacteria against different biocides. Planktonic L. pneumophila strains were suspended in tap water while sessile ones were grown on stainless steel that is used in construction of the cooling towers, then both group of strains were exposed to the biocide. The sensitivity of both planktonic and sessile populations of L. pneumophila strains to the biocide was different. The biocide was found effective below recommended dosages (1000-2000 mg/L) against planktonic populations of L. pneumophila, whereas it was determined that higher than the recommended dosages were required for sessile populations. The environmental isolates were more resistant to the biocide than the ATCC isolate was. The results indicated that studying only the planktonic populations of L. pneumophila for biocide tests might not be sufficient to provide the optimum dosage and contact time information for field trials. Therefore, biocidal activity of a water treatment chemical must be evaluated in terms of dosage and contact times on both planktonic and sessile bacteria.

show abstract

A laboratory apparatus for the generation and biocide efficacy testing of Legionella biofilms

Cited by 26 publications

References 11 publications

Legionella and Legionnaires' Disease: 25 Years of Investigation

Legionella and Legionnaires' Disease: 25 Years of Investigation

Efficacy of Colloidal Silver-Hydrogen Peroxide and 2-Bromo-2-nitroporopane-1,3-diol Compounds Against Different Serogroups of Legionella pneumophila Strains

Efficacy of a quaternary ammonium compound against planktonic and sessile populations of differentLegionella pneumophila strains

Contact Info

Product

Resources

About