Scientists in New Zealand are working with their Australian counterparts to discover ways to stamp out the Queensland fruit fly population.
They are also working to improve traps and lures to capture flies in incursions like the one in Auckland's suburb of Grey Lynn.
The number of flies found in Grey Lynn has now risen to eight. Larvae and pupa have also been found in fruit.
The Ministry for Primary Industries said it remained confident it was a localised population that could be eradicated.
Plant and Food Research's chief scientist Richard Newcomb said more than 90 percent of incursions had been successfully eradicated world wide, and he was confident this one would be too.
Dr Newcomb said scientists were trying techniques to reduce the numbers of Queensland fruit flies in Australia, to lower the risk of incursions in New Zealand.
Work to improve the monitoring and luring of fruit flies was also important.
"Obviously if we could improve the kind of lures then we could improve the monitoring for the actual fly itself. Some of the work we're doing in Australia is helping the Australians reduce the density of the pest over there. Obviously our preference is to try and get the numbers of Queensland fruit fly down in Australia because if we can get the numbers down there, then the likelihood of further incursions will be reduced," he said.
Plant and Food Research was involved in research to help the south Australian Government set up what was called a sterile fly facility, where sterile flies were produced and then releasd into an area that already had the Queensland fruit fly.
Those sterile flies mated with the non-sterile flies and reduced the amount of fertile offspring that were produced, he said.
Meanwhile, there has been a plea from the horticulture sector for people going to the one-day match between Australia and New Zealand, in Auckland tomorrow, to leave any fruit and vegetables at home.