A case of mistaken identity – reappraisal of the species of canid and felid hookworms (Ancylostoma) present in Australia and India

Abstract

This study serves to clarify the current status of canid and felid Ancylostoma species present in Australia. The morphological identification of A. ceylanicum from cats for the first time in Townsville, Australia, appears to be in error, together with the genetic markers provided for the species. Morphological and genetic data presented herein provide strong evidence that the hookworms from cats in Towsville are not A. ceylanicum as previously identified (i.e. the first report of this species in Australia), but are A. braziliense. Therefore the subsequent genetic markers established for A. ceylanicum in subsequent molecular studies based on these Townsville specimens should also be attributed to A. braziliense. Based on this information, a study of canine hookworm species present in northern India is also in error and it is apparent that the hookworms found in this region are those of A. ceylanicum. The distribution of A. braziliense and A. ceylanicum in the Americas and Asia Pacific region is discussed together with the importance of combining parasite morphology with genetic data for parasite diagnosis in epidemiological studies.

The veterinary and public health significance of hookworm in dogs and cats in Australia and the status of A. ceylanicum

“…The dingo was probably introduced 4000 years ago, but the parasites that accompanied it are unknown (Beveridge, 2002). It was puzzling that A. ceylanicum had not been found previously in Australia given that A. braziliense, A. caninum and A. tubaeformehave all been recovered from Australian dogs and cats in the past (Traub et al, 2006). Furthermore, the absence of A. ceylanicumfrom northern Australia was intriguing given the endemic distribution of this parasite in neighbouring regions: Malaysia (Yoshida et al, 1973;Sheikh et al, 1985), Borneo (Choo et al, 2000), Indonesia (Margono et al, 1979), Papua New Guinea (Anten and Zuidema, 1964) and the Solomon Islands (Beveridge, 2002).…”

“…DNA was then isolated from the supernatant tubaeforme, A. ceylanicum, A. braziliense and U. stenocephala was amplified using previously published primers, PCR reaction, and cycling conditions (Traub et al, 2004). An amendment to this PCR was however recently made by Traub et al (2006) whereby it was recognized that the reference sequence of A. ceylanicum was in fact that of A. braziliense. Hence RTGHFI (5′-CGTGCTAGTCTTCAGGACTTTG-3′) and RTABCR1 (5′-CGGGAATTGCTATAAGCAAGTGC-3′) were used to amplify a 545 bp region of A. caninum, A. tubaeforme, A. ceylanicum and U.…”

“…However, the only reports of A. ceylanicum in Australia (Stewart, 1994;Gasser et al, 1996;Adams, 2004) have been found to be based on a misidentification of A. braziliense as A. ceylanicum (Traub et al, 2006;e Silva et al, 2006).…”

Molecular Characterization of Ancylostoma braziliense Larvae in a Patient with Hookworm-Related Cutaneous Larva Migrans

“…7 The advent of biomolecular techniques has shown that morphological criteria are not reliable enough to distinguish between different species of Ancylostoma larvae. 7 Therefore, this case is the first case of HrCLM in which a hookworm species could be identified by molecular techniques.…”

Comparative anthelmintic efficacy of ivermectin delivered through different routes in gastrointestinal nematode infected dogs

“…Gastrointestinal helminthiasis is the most commonly encountered disease in dogs rearing across the globe including India (Traub et al 2007). Among the gastrointestinal helminths, both Ancylostoma spp.…”