Relevanz von Legionellen

im Verteilnetz

Colin Schmid

Kantonales Labor Zürich and UZH Institute of
Medicinal Microbiology
Project lead:  Dr. Hans Peter Füchslin and
Prof. Dr. Hubert Hilbi

18.01.2023

LiVN

Outline

🥽 Introduction

🧫 Methods

📊 Results

🎙 Discussion

🚀 Future Directions

Legionellosis infections in the Cantons of Zürich and Ticino

Seasonality of incidence in Zürich,
Ticino is constantly high according to gov

Coincidence with seasonal change in temperatures

🥽 Introduction

Data provided by the Federal Office of Public Health FOPH - BAG

Why Ticino?

Data provided by the Federal Office of Public Health FOPH - BAG

Collaboration with two water suppliers in the cantons of Zürich and Ticino

The aim is quantification and isolation of Legionella in water supply networks.

🧫 Methods

Workflow

Sample collection

PCR

Cultivation with APT

The LiVN Workflow™

ddPCR

📊 Results

PCR Zurich (spp with a grain of salt, Lp has been described as "anecdotal")

PCR Ticino (individual stubs,
comparing strategies, Lp found but statistically unreliable, outlook)

APT

Isolates

ddPCR Zürich: Legionella species

ddPCR data Legionella species for Zürich: Copies per Liter for 5 sampling sites for ~6 months

ddPCR Zürich: Legionella pneumophila

ddPCR data Legionella pneumophila for Zürich: Copies per Liter for 5 sampling sites for ~6 months

Mycelium growing on millet grain substrate CC BY-NC-SA 4.0 2021 by Colin Schmid

APT LugB

APT LugC

PCR found 18 681 copies/L Legionella pneumophila in the hydrant that had 7900 copies/L in October

With MALDI-TOF no Legionella at all could be identified in an Amoebae Plate Test for this sample from December 6th.

🎙 Discussion

Refined Sample Collection

Established PCR

Amoebae Plate Test

Isolates

🚀 Future Directions

🧫

Thanks for your attention. I'd be happy to answer your questions and hear your thoughts now.

you can reach my via mail: mail@colinschmid.net

visit: colinschmid.net