Hooked on a [gut] feeling - Hookworm linked to human gut disease

Queensland researchers have discovered that canine hookworm, can lead to human gut disease through oral ingestion of the hookworm, and not only through the skin as previously thought.

The possibility of contracting gut disease always has been one of the more unpleasant facts of life for people living in most of Australia's humid tropical and sub-tropical regions.

In recent years, it has been established that the most widespread hookworm species, which parasitises dogs in these areas, can cause gut disease.

But until now, it had been thought that most cases attributed to the dog hookworm Ancylostoma caninum occurred after absorption through the skin, as people in these regions often walk barefoot in areas where dog faeces contaminate grass and soil.

Research by Juergen K Landmann and Dr Paul Prociv from The University of Queensland's Department of Microbiology and Parasitology, published in the latest edition of the Medical Journal of Australia, suggests that swallowing infective larvae of the dog hookworm can cause them to develop directly into adult worms in the human gut.

The trial involved administering relatively small numbers of infective larvae orally and through the skin to an informed healthy volunteer under medical supervision.

The main routes of oral infection probably lie in drinking soil-contaminated water, eating soil-contaminated food - for example, on fresh vegetables - or by eating infected meat.

The researchers say grazing animals and free-range poultry can become infected from soil contaminated by dogs, and that if people eat meat from such animals when undercooked, it may lead to them developing adult hookworms in the gut.

Dr Prociv adds that though more extensive studies are needed, oral infection may be a more likely route for the development of human gut disease than via absorption through the skin.

The Medical Journal of Australia is a publication of the Australian Medical Association.

CONTACT: Juergen K Landmann (07) 3898 9654 B/H; (07) 3219 3480 A/H

Email: juergen.landmann@dpi.qld.gov.au

Judith Tokley, AMA Public Affairs (0408) 824 306