Spatial analysis of targeted surveillance for screw-worm fly (Chrysomya bezziana or Cochliomyia hominivorax) in Australia

Aust Vet J. 2014 Jul;92(7):254-62. doi: 10.1111/avj.12197.

Abstract

Objective: To assess Australia's targeted surveillance to detect an incursion of screw-worm fly (Chrysomya bezziana).

Methods: A multi-criteria analysis shell was used to combine data on potential pathways of entry, availability of host species and environmental factors affecting survival of screw-worm fly in order to map spatial variation in the relative likelihood of a screw-worm fly incursion into Australia. Australia's current screw-worm fly surveillance activities were reviewed to determine whether they are located in the areas of highest likelihood of an incursion.

Results: Under average environmental conditions, an incursion of screw-worm fly in Australia is relatively more likely to occur along the north coast, down the eastern seaboard or in the south-east. Cold winter temperatures would limit the environmental suitability for screw-worm fly survival to the north and north-east coast and adjacent inland areas. Australia's current targeted surveillance conducted by the Northern Australia Quarantine Strategy program of the Australian Department of Agriculture (adult screw-worm fly trapping and myiasis sampling) correlated well with areas considered to have a high relative likelihood of an incursion of screw-worm fly. Adult fly trapping conducted at sea ports was less well correlated.

Discussion: Changes to surveillance at sea ports are proposed to better target areas considered to have a higher relative likelihood of screw-worm fly incursion. These include increasing the trapping intensity along the north and north-east coasts and shifting surveillance activity from the west coast to the south-east.

Keywords: Australia; cattle; screw-worm fly; spatial analysis; surveillance.

MeSH terms

  • Animals
  • Australia / epidemiology
  • Climate
  • Communicable Disease Control / methods
  • Diptera / physiology*
  • Geographic Mapping
  • Insect Vectors
  • Population Surveillance / methods*
  • Screw Worm Infection / prevention & control
  • Spatial Analysis*
  • Surveys and Questionnaires