Naslov
Decreasing Pasteurization Treatment Efficiency against Amoeba-Grown Legionella pneumophila - Recognized Public Health Risk Factor

Autori
Knežević, Maša ; Rončević, Dobrica ; Vukić Lušić, Darija ; Mihelčić, Mirna ; Kogoj, Rok ; Keše, Darja ; Glad, Marin ; Cenov, Arijana ; Ožanič, Mateja ; Glažar Ivče, Daniela ; Šantić, Marina

Izvornik
International Journal of Environmental Research and Public Health (1660-4601) 19 (2022), 3; 1099, 20

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Acanthamoeba ; environment ; infection ; Legionella ; water

Sažetak
Legionellae are gram-negative bacteria most commonly found in freshwater ecosystems and purpose-built water systems. In humans, the bacterium causes Legionnaires’ disease (LD) or a Pontiac fever. In this study, the different waters (drinking water, pool water, cooling towers) in which Legionella pneumophila has been isolated were studied to assess the possible risk of bacterial spreading in the population. The influence of physical and chemical parameters, and interactions with Acanthamoeba castellanii on L. pneumophila, were analyzed by Heterotrophic Plate Count, the Colony-forming units (CFU) methods, transmission electron microscopy (TEM), and Sequence-Based Typing (SBT) analysis. During the study period (2013–2019), a total of 1932 water samples were analyzed, with the average annual rate of Legionella-positive water samples of 8.9%, showing an increasing trend. The largest proportion of Legionella-positive samples was found in cooling towers and rehabilitation centers (33.9% and 33.3%, respectively). Among the isolates, L. pneumophila SGs 2–14 was the most commonly identified strain (76%). The survival of Legionella was enhanced in the samples with higher pH values, while higher electrical conductivity, nitrate, and free residual chlorine concentration significantly reduced the survival of Legionella. Our results show that growth in amoeba does not affect the allelic profile, phenotype, and morphology of the bacterium but environmental L. pneumophila becomes more resistant to pasteurization treatment

Izvorni jezik
Engleski

Znanstvena područja
Biologija, Temeljne medicinske znanosti, Javno zdravstvo i zdravstvena zaštita, Biotehnologija u biomedicini (prirodno područje, biomedicina i zdravstvo, biotehničko područje)

POVEZANOST RADA