Work

Emerging human and canine leptospirosis in New South Wales: insights from a One Health geospatial study

Year: 2025

Type: article

Abstract: After an apparent absence of disease, 79 cases of canine leptospirosis were reported in New South Wales (NSW), Australia between 2017 and 2023. Between 2016 and 2023, 281 human leptospirosis cases were reported in NSW. Our aim was to compare the geospatial distribution and causative serovars of canine and human cases to investigate if cases are possibly associated. Human data ( n = 190) included Statistical Area Level 3 (SA3)-location, place of acquisition, and serovar; cases acquired outside NSW were excluded. Canine data comprised postcodes (allocated to corresponding SA3) and serovar. Spatial patterns for human and canine cases were mapped, and correlations between human and canine cases were examined. In dogs, serovar Australis ( n = 23, 29%) and Copenhageni ( n = 14, 18%) were most common, whereas in humans it was serovar Arborea ( n = 111, 58%) and Hardjo ( n = 13, 7%). Serovars causing disease in both humans and dogs were Australis, Copenhageni, Hardjo, Pomona, and Robinsoni. In southeastern NSW, serovar Australis infections increased in both dogs and humans. Canine cases were significantly clustered in Greater Sydney and the South Coast whereas human cases were mainly centered around the North Coast with no significant clustering. Overall, there were nine SA3s where both canine ( n = 38) and human ( n = 51) cases were reported. There was no evidence of correlation between numbers of human and canine cases at the SA3 level (Spearman’s rank correlation coefficient [ r ] = −0.053, P = 0.641) and no overlap between specific serovars at the spatial level. Our results do not support dog−human transmission or common sources of infection. • 190 human and 79 canine leptospirosis cases acquired in New South Wales, Australia were reported between 2016 and 2023; • Serovar Australis was the most common serovar in dogs and is becoming more prevalent in South East Australia in both dogs and humans; • Serovar Arborea was the most common serovar in humans; • There is no apparent dog−human transmission of Leptospira or common sources of infection.

Source: Science in One Health

DOI: 10.1016/j.soh.2025.100126

Authors: Christine Griebsch, Jacqueline Norris, Michael P. Ward

Institution: The University of Sydney

Language: English

Topic: Leptospirosis research and findings

Subfield: Parasitology

Field: Immunology and Microbiology

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $1,800