Dr Simon Reid is working to protect Australian livestock.

The bite of a March fly could potentially threaten whole populations of Australia’s native and domestic animals according to Dr Simon Reid.

Dr Reid joined Murdoch at the start of this year to continue his investigation of surra, a protozoan parasite transmitted on the mouthparts of biting flies.

Surra, which is related the human African sleeping sickness spread by tsetse flies, is endemic throughout the world’s tropical regions including south east Asia.

The disease was probably introduced to the border areas of Irian Jaya with cattle brought by transmigrants from Java and other western islands of Indonesia in the 1970s.

Though it is still unclear how far the disease has spread, surra may have since infected animals throughout Papua New Guinea.

Australia’s strict quarantine laws have prevented its introduction into the country to date, but there are concerns that the disease will eventually spread through the Torres Strait islands to the mainland.

Surra can infect all mammals except humans, resulting in poor weight gain and occasional outbreaks of clinical disease in cattle, pigs and sheep and an acute fatal disease in horses, camels and smaller animals such as dogs.

Dr Reid’s investigations during his PhD revealed that Australia’s native fauna are also extremely vulnerable to the disease.

“Recent work has demonstrated that two species of kangaroo, agile wallabies and pademelons, are highly susceptible to infection, suffering from acute clinical disease with high mortality,” he said.

“Populations of dingoes could also be decimated by surra, due to animals scavenging on the carcasses of infected animals.”

“The overwhelming impact of surra on livestock, feral and native species means that the disease could have devastating effects and could become endemic if introduced to Australia.”

Dr Reid explained that efficient transmission of the parasite requires animals to be congregated, such as when animals come together at mating, in species that live in family groups and when animals are mustered.

“The disease would therefore spread most rapidly in regions where feral pigs, kangaroos and cattle are most numerous,” he said.

In particular, Dr Reid believes that surra would spread quickly during the dry season, when wild and feral species gather together around watering points.

Dr Reid’s research to date has indicated that the existing diagnostic tests for surra are inadequate to track the spread of the disease if it should enter Australia.

As a result, Dr Reid aims to develop novel approaches to diagnosis this illness and identify methods to protect Australia’s livestock and wildlife from infection.

Due to the inaccessability and widespread susceptibility of Australia’s fauna, surra would probably not be effectively controlled using the chemotherapeutic agents employed in other countries.

Therefore Dr Reid believes that the development of alternative control strategies is essential for the protection of Australia’s native fauna if surra were to become endemic in the country.