Are parasites a problem in Australia?

Agriculture

Parasites are a significant burden to Australia's meat, wool, dairy and aquaculture industries. Are they breaking the back of our rural industries?

Australia's meat, wool, dairy and aquaculture industries produce more than $13 billion worth of products each year and bring in more than $7 billion in export earnings - an income that relies heavily on Australia maintaining its reputation of having livestock that is relatively disease-free.

While strict quarantine laws keep our borders free of new disease, our livestock industry suffers enormous hardship from parasites that we neither understand nor adequately control.

Worm infestation alone costs the Australian sheep industry more than $220 million a year - a figure expected to increase 4-5 times within a decade, due to drug resistance, according to a 2002 report by the Federation of Scientific and Technological Studies (http://parasite.org.au/Parasite_paper.pdf).

At a time when agriculture remains a vulnerable choice of career, infestation with parasites can be the last straw for a struggling farmer of livestock.

Australia's primary industries and wildlife are susceptible to several parasites (eg, Haemonchus, Fasciola, Ostertagia, Trichostrongylus, Babesia, Anaplasma and Neospora in sheep and cattle, Eimeria in poultry, Neoparamoeba in fish).

Australia's waterways are vulnerable to contamination with parasites that affect both animals and humans (eg, Cryptosporidium, Giardia and Toxoplasma).

Humanity

Parsites are a human condition.

In Australia, we are spared the most devastating parasitic diseases of humans such as malaria, leishmaniasis, sleeping sickness and schistosomiasis but Australian travelers regularly return home with these tropical diseases.

And, Australia is plagued by a large number of common, and sometimes very serious, human parasites. The burden of parasites is particularly heavy amongst Aboriginal communities in the North.

In Australia we contract the following infections on a regular basis. These infections range from the annoying to the life-threatening:

• Protozoan - Acanthamoeba, Cryptosporidium, Dientamoeba, Giardia, Isospora, Naegleria, Toxoplasma and Trichomonas.



• Helminth - Ancylostoma, Angiostrongylus, Ascaris, Dirofilaria, Echinococcus, Enterobius, Fasciola, Hymenolepis, Spirometra, Strongyloides, Taenia, Toxocara, Trichuris and Trichostrongylus.



• Ectoparasite - Pediculus, Phthirus and Sarcoptes.

The future

The extent of Australia's parasite burden is poorly understood.

We do know, however, that several parasites introduced at the time of European settlement (eg, Fasciola, Echinococcus, Toxoplasma, Sarcoptes) have adapted well and that they are now a risk to our wildlife.

We also know that certain parasites present in Southeast Asia and Pacific regions are major threats to Australian livestock and wildlife.

But our lack of knowledge puts Australia's health and economy at risk because we cannot predict which exotic parasites may establish themselves in Australia in the future and what sort of impact they may have on our unique fauna.