PLoS Negl Trop Dis. 2016 Dec 9;10(12):e0005174. doi: 10.1371/journal.pntd.0005174. eCollection 2016.
- 1Infectious
Bacterial Diseases Research Unit, National Animal Disease Center,
Agricultural Research Service, United States Department of Agriculture,
Ames, Iowa, United States of America.
- 2University Centre of Veterinary Medicine JU-UAK, University of Agriculture, Krakow, Poland.
- 3OIE Leptospirosis Reference Laboratory, Veterinary Sciences Division, AFBI, Belfast, Northern Ireland, United Kingdom.
- 4UCD School of Agriculture & Food Science, University College Dublin, Belfield, Dublin, Ireland.
- 5Ecosystems
and Environment Research Centre, School of Environment and Life
Sciences, University of Salford, Salford, United Kingdom.
- 6UCD School of Biology & Environmental Science and UCD Earth Institute, University College Dublin, Belfield, Dublin, Ireland.
- 7UCD
Centre for Food Safety, School of Public Health, Physiotherapy &
Sports Science, University College Dublin, Belfield, Dublin, Ireland.
Abstract
The
greater white-toothed shrew (Crocidura russula) is an invasive
mammalian species that was first recorded in Ireland in 2007. It
currently occupies an area of approximately 7,600 km2 on the island. C.
russula is normally distributed in Northern Africa and Western Europe,
and was previously absent from the British Isles. Whilst invasive
species can have dramatic and rapid impacts on faunal and floral
communities, they may also be carriers of pathogens facilitating disease
transmission in potentially naive populations. Pathogenic leptospires
are endemic in Ireland and a significant cause of human and animal
disease. From 18 trapped C. russula, 3 isolates of Leptospira were
cultured. However, typing of these isolates by standard serological
reference methods was negative, and suggested an, as yet, unidentified
serovar. Sequence analysis of 16S ribosomal RNA and secY indicated that
these novel isolates belong to Leptospira alstonii, a unique pathogenic
species of which only 7 isolates have been described to date. Earlier
isolations were limited geographically to China, Japan and Malaysia, and
this leptospiral species had not previously been cultured from mammals.
Restriction enzyme analysis (REA) further confirms the novelty of these
strains since no similar patterns were observed with a reference
database of leptospires. As with other pathogenic Leptospira species,
these isolates contain lipL32 and do not grow in the presence of
8-azagunaine; however no evidence of disease was apparent after
experimental infection of hamsters. These isolates are genetically
related to L. alstonii but have a novel REA pattern; they represent a
new serovar which we designate as serovar Room22. This study
demonstrates that invasive mammalian species act as bridge vectors of
novel zoonotic pathogens such as Leptospira.