March 2, 2026
Biosecurity Queensland has confirmed the detection of varroa mites in south-east Queensland with resistance to synthetic pyrethroid insecticides.
A spokesperson said genetic testing by the Elizabeth Macarthur Agricultural Institute on February 24 identified mutations linked to resistance.
Testing at several Queensland sites, including locations where treatment failure had been reported, confirmed reduced effectiveness of the pyrethroid Bayvarol.
At this stage, the distribution of resistant mites appears limited.
Further tracing and testing are underway to better understand the extent of spread and to guide management advice for industry.
This is the first confirmed case of pyrethroid-resistant varroa mite in Queensland. While spread appears limited at present, there is potential for further movement over time.
Scientists are looking into how the resistance started. There are 3 possible reasons:
Beekeepers have been urged to monitor their mite levels both before and after treatments to ensure mite populations have reduced.
If they believe their treatment is not working, they should contact the DPI by email
