High-throughput multiplex qPCRs for the surveillance of zoonotic species of canine hookworms

PLoS Negl Trop Dis. 2020 Jun 15;14(6):e0008392. doi: 10.1371/journal.pntd.0008392. eCollection 2020 Jun.

Abstract

The canine hookworms Ancylostoma braziliense, Ancylostoma ceylanicum, Ancylostoma caninum and Uncinaria stenocephala are not only capable of producing morbidity and mortality in dogs but are also neglected tropical zoonoses. Each hookworm species differs considerably in its geographical distribution, life cycle, biology, pathogenic impacts on both canine and human hosts, zoonotic potential, and response to treatment with anthelminthics. Here we describe the development and validation of two Taq-Man based multiplex PCR assays capable of detecting and differentiating all four canine hookworm species in faeces of naturally infected dogs. The analytical sensitivity of both assays was assessed using 10-fold serial dilutions of synthetic gene block fragments containing individual sequence targets of each hookworm species. The sensitivity of the assays and ability to detect mixed species infections were compared to a conventional PCR-Restriction Fragment Length Polymorphism based-approach when applied to laboratory and field samples from endemic areas. The qPCRs detected at least one species of hookworms in 82.4% of PCR-RFLP-negative but microscopy-positive samples. The qPCRs detected an additional 68% mixed infections with different species of canine hookworms, and additional single species infection with A. caninum (47%), U. stenocephala (33%) and A. ceylanicum (0.02%) that were missed by PCR-RFLP. These multiplex qPCR assays will assist field based epidemiological surveillance studies towards an accurate and sensitive monitoring of canine hookworm infections in dogs, to inform their species-specific zoonotic risks to populations living in endemic areas, globally.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ancylostoma / genetics
  • Ancylostoma / isolation & purification
  • Ancylostomatoidea / classification
  • Ancylostomatoidea / genetics*
  • Ancylostomatoidea / isolation & purification*
  • Ancylostomiasis / diagnosis
  • Ancylostomiasis / epidemiology
  • Ancylostomiasis / physiopathology
  • Animals
  • DNA, Helminth / analysis
  • DNA, Helminth / genetics
  • Dog Diseases / diagnosis*
  • Dog Diseases / epidemiology
  • Dog Diseases / physiopathology
  • Dogs
  • Feces / parasitology
  • Hookworm Infections / diagnosis*
  • Hookworm Infections / physiopathology
  • Humans
  • Multiplex Polymerase Chain Reaction / methods*
  • Multiplex Polymerase Chain Reaction / veterinary*
  • Polymorphism, Restriction Fragment Length
  • Sensitivity and Specificity
  • Zoonoses / diagnosis
  • Zoonoses / epidemiology
  • Zoonoses / physiopathology

Substances

  • DNA, Helminth

Grants and funding

Funding for this work was provided by Boehringer Ingelheim Animal Health. Luca Massetti and Patsy A. Zendejas are recipients of Melbourne Research Scholarship from the University of Melbourne. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.