Journal of Applied & Environmental Microbiology
ISSN (Print): 2373-6747 ISSN (Online): 2373-6712 Website: Editor-in-chief: Sankar Narayan Sinha
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Journal of Applied & Environmental Microbiology. 2021, 9(1), 1-4
DOI: 10.12691/jaem-9-1-1
Open AccessArticle

Presence of Legionella Longbeachae in Pine but not Composted Green Waste Used in Manufacture of Potting Soils in New Zealand

Ali Mohammadi1, Stephen T. Chambers1, , Sandy Slow1, Trevor Anderson2, Jonathan Williman3, Pippa Scott1, David Murdoch1 and Amy Scott-Thomas1

1Department of Pathology and Medical Science, University of Otago, Christchurch, Christchurch New Zealand

2Canterbury Health Laboratories, Christchurch, New Zealand

3Population Health, University of Otago, Christchurch, Christchurch New Zealand

Pub. Date: May 31, 2021

Cite this paper:
Ali Mohammadi, Stephen T. Chambers, Sandy Slow, Trevor Anderson, Jonathan Williman, Pippa Scott, David Murdoch and Amy Scott-Thomas. Presence of Legionella Longbeachae in Pine but not Composted Green Waste Used in Manufacture of Potting Soils in New Zealand. Journal of Applied & Environmental Microbiology. 2021; 9(1):1-4. doi: 10.12691/jaem-9-1-1


In this research we compared the proportion of samples taken at different stages in the manufacturing process of potting soils that were qPCR positive for Legionella longbeachae. This included samples of composted feed stock, mixing sites and bagged products. Feedstock, manufacturing sites, and final retail products at three locations across the North and South Islands of New Zealand were tested for L. longbeachae DNA by qPCR. Positive tests were found on samples of composted pine bark 14/360 (3.9%), pine sawdust 5/185 (2.7%) and pre-bagged or bagged potting soils 9/200 (4.5%). All samples from peat (n = 20), green waste (n = 100), and mixing areas (n = 73) were negative. Samples that contained pine bark or pine sawdust were more likely to be qPCR positive (28/818, 3.4%) than other samples (0/355, 0%; P<0.001). L. longbeachae probably reaches the manufacturing sites from fresh pine bark and persists through the composting and manufacturing process, leading to a wide distribution following the purchase.

Legionella longbeachae compost pine Legionnaires’ disease LD potting soil

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