Media Release

September 17 2009

UniSA experts assist New Zealand mosquito eradication

Dr Craig Williams in the laboratory at UniSA UniSA researchers are assisting in the New Zealand Government’s fight to eradicate the southern saltmarsh mosquito from the island country.

A vector of the debilitating Ross River virus disease, the southern saltmarsh mosquito is an Australian mosquito common in South Australia that entered New Zealand about 10 years ago.

Dr Craig Williams from UniSA’s Mosquito and Plant Research Group said unlike South Australia, New Zealand is currently free of Ross River virus.

“The New Zealand Government is really keen to eradicate this mosquito to prevent Ross River virus getting into the country,” said Dr Williams.

“It’s a preventative health measure – they’re spending the dollars now on eradicating the mosquito rather than risking a new disease entering the country ... because if that happens, it’s very expensive, millions and millions of dollars a year.”

Now heading into the South Australian mosquito and Ross River virus season, Dr Williams and team member Christie Bader recently completed a large research report on the southern saltmarsh mosquito for the New Zealand Government.

“No one nation has ever tried to eradicate an insect pest in this way, to completely eradicate it from a country,” Dr Williams said.

“Because we have the same mosquito here in Adelaide, we can do the research in SA that tells New Zealand things like how long these mosquitoes live, what’s the best way to catch them and how long their eggs can last. We’ve just completed a large surveillance report to help with their eradication project.”

Dr Williams said the southern saltmarsh mosquito was common in Adelaide during winter and spring, while the northern saltmarsh mosquito was “the one that mauls people in Adelaide during February and March.”

“We’re currently gathering data from 30 mosquito monitoring sites along the River Murray plus sites in the metropolitan area to assess mosquito numbers and Ross River Virus risk for the coming season,” he said. He said South Australia averaged 100 to 150 Ross River Virus cases per year, whereas in an epidemic year up to 600 cases could be reported.