title: The Prevalence of Angiostrongylus cantonensis/mackerrasae Complex in Molluscs from the Sydney Region.
abstract: Angiostrongylus cantonensis and Angiostrongylus mackerrasae are metastrongyloid nematodes that infect various rat species. Terrestrial and aquatic molluscs are intermediate hosts of these worms while humans and dogs are accidental hosts. Angiostrongylus cantonensis is the major cause of angiostrongyliasis, a disease characterised by eosinophilic meningitis. Although both A. cantonensis and A. mackerrasae are found in Australia, A. cantonensis appears to account for most infections in humans and animals. Due to the occurrence of several severe clinical cases in Sydney and Brisbane, the need for epidemiological studies on angiostrongyliasis in this region has become apparent. In the present study, a conventional PCR and a TaqMan assay were compared for their ability to amplify Angiostrongylus DNA from DNA extracted from molluscs. The TaqMan assay was more sensitive, capable of detecting the DNA equivalent to one hundredth of a nematode larva. Therefore, the TaqMan assay was used to screen molluscs (n=500) of 14 species collected from the Sydney region. Angiostrongylus DNA was detected in 2 of the 14 mollusc species; Cornu aspersum [14/312 (4.5%)], and Bradybaenia similaris [1/10 (10%)], which are non-native terrestrial snails commonly found in urban habitats. The prevalence of Angiostrongylus spp. was 3.0% ± 0.8% (CI 95%). Additionally, experimentally infected Austropeplea lessoni snails shed A. cantonensis larvae in their mucus, implicating mucus as a source of infection. This is the first Australian study to survey molluscs using real-time PCR and confirms that the garden snail, C. aspersum, is a common intermediate host for Angiostrongylus spp. in Sydney.
authors.affiliation: Department of Microbiology, SydPath, St. Vincent's Hospital, Victoria St, Darlinghurst, NSW, Australia; i3 Institute, University of Technology, Sydney, Ultimo, NSW, Australia.
authors.forename: Douglas
authors.initials: D
authors.lastname: Chan
authors.affiliation: i3 Institute, University of Technology, Sydney, Ultimo, NSW, Australia; School of Medical and Molecular Sciences, University of Technology, Sydney, Ultimo, NSW, Australia.
authors.forename: Joel
authors.initials: J
authors.lastname: Barratt
authors.affiliation: Department of Microbiology, SydPath, St. Vincent's Hospital, Victoria St, Darlinghurst, NSW, Australia.
authors.forename: Tamalee
authors.initials: T
authors.lastname: Roberts
authors.affiliation: Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR, Westmead Hospital, Westmead, NSW, Australia.
authors.forename: Rogan
authors.initials: R
authors.lastname: Lee
authors.affiliation: Malacology Department, Australian Museum, Sydney, NSW, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Shea
authors.affiliation: Department of Microbiology, SydPath, St. Vincent's Hospital, Victoria St, Darlinghurst, NSW, Australia.
authors.forename: Deborah
authors.initials: D
authors.lastname: Marriott
authors.affiliation: Department of Microbiology, SydPath, St. Vincent's Hospital, Victoria St, Darlinghurst, NSW, Australia.
authors.forename: John
authors.initials: J
authors.lastname: Harkness
authors.affiliation: Centre for Veterinary Education, University of Sydney, Camperdown, NSW, Australia.
authors.forename: Richard
authors.initials: R
authors.lastname: Malik
authors.affiliation: School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia.
authors.forename: Malcolm
authors.initials: M
authors.lastname: Jones
authors.affiliation: School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia.
authors.forename: Mahdis
authors.initials: M
authors.lastname: Aghazadeh
authors.affiliation: School of Medical and Molecular Sciences, University of Technology, Sydney, Ultimo, NSW, Australia.
authors.forename: John
authors.initials: J
authors.lastname: Ellis
authors.affiliation: Department of Microbiology, SydPath, St. Vincent's Hospital, Victoria St, Darlinghurst, NSW, Australia.
authors.forename: Damien
authors.initials: D
authors.lastname: Stark
mesh_terms: D000801:Angiostrongylus / Q000302:isolation & purification*; D017185:Angiostrongylus cantonensis / Q000302:isolation & purification*; D000818:Animals; D001315:Australia; D008969:Molecular Sequence Data; D012908:Snails / Q000469:parasitology*; D017206:Strongylida Infections / Q000635:transmission*