Identification of Legionella spp. in Environmental Water Samples by ScanVIT-Legionella™ Method in Spain

Abstract

Rapid and more sensitive methods for the detection and quantification of viable Legionella cells have been developed. In this paper, a comparative analysis of environmental water samples using the ScanVIT-Legionella TM method and the traditional ''gold standard'' method of culturing is realised indicating the usefulness of the ScanVIT method. The ScanVIT-Legionella TM method was performed on environmental water samples from different locations of Huesca region (Spain). Legionella micro-colonies should appear green colour and Legionella pneumophila micro-colonies appear red. Twenty-one environmental water samples analysed by standard culture plus five control samples (Two sterile water samples with Legionella as positive controls and three sterile water samples as negative controls). All of them were used to apply ScanVIT-Legionella TM method. From of 21 environmental samples eleven were positive, six negative with both methods and four samples were negative for culture method and positive for ScanVIT-Legionella TM method. The positive control samples were positive and the negative were negative for both methods. A comparative analysis of the results obtained with two methods showed a strong positive determination coefficient (R 2 = 0.99753). The results demonstrate the usefulness of the ScanVITLegionella TM method as a rapid diagnostic tool in order to provide a diagnosis as quick as possible. ScanVITLegionella TM method offers a series of advantages such as quickly diagnosis, higher sensitivity and the possibility to identify Legionella spp. and L. pneumophila simultaneously.

Detection of <i>Legionellae pneumophila</i> in Waters by Culture and Polymerase Chain Reaction

“…Many factors may explain the low sensitivity rate of detection L. pneumophila by culture in water samples, such as: the presence of viable but non-culturable cells, loss of viability of bacteria after collection, and low concentration of legionellae in the samples [21]. Similar observations were reported by other authors [22] [23] [24]. The reason for the significant discrepancy between PCR and culture results for Legionella in water samples is the greater positivity rates for PCR than culture [25].…”

Legionella surveillance in stagnant water systems during COVID-19 lockdown in Istanbul

“…Legionella pneumophila colonies appear red in color (Figure 2) on ScanVIT membrane, whereas those of other Legionella spp. would be in green color (Gruas et al, 2013). The detection of Legionella takes place on a cultivated filter brought into contact with the gene probes marked with a dye.…”

Molecular detection of Acanthamoeba spp., Naegleria fowleri and Vermamoeba (Hartmannella) vermiformis as vectors for Legionella spp. in untreated and solar pasteurized harvested rainwater

“…While L. longbeachae is generally isolated from soil, including potting soil [ 71 ], this microorganism has previously been isolated from water samples collected from hospital reticulation systems and cooling towers and is able to proliferate in Acanthamoeba polyphaga [ 72 – 74 ]. In addition, while L. pneumophila serotype 1 is responsible for most of the human reported infections, 17 additional species have also been associated with disease and these include L. longbeachae, L. micdadei , L. anisa and L. bozemanii [ 75 ]. BLAST analysis also revealed that L. norrlandica was of the dominant Legionella spp.…”