Varroa mites are a plague to all honey bees and beekeepers in the US and most of the world, but beekeepers have limited tools available for Varroa control. One widely used tool is Amitraz/Apivar strips. Although Amitraz has been effective for almost two decades, we know from experience that using synthetic compounds puts pressure on Varroa populations and can lead to mite resistance. This happened with fluvalinate (Apistan) and Coumaphos (Checkmite) within 10-15 years of use. As we pass those landmarks using Amitraz for Varroa control, beekeepers and scientists are on the lookout for treatment efficacy and any signs of resistant mites.
This year PAm selected two projects- both funded by the National Honey Board- to follow up and gather the scientific data where beekeepers have reported that Amitraz treatments may not be working. Dr. Jeff Pettis, and Drs. Shelley Hoover and Ramesh Sagili will all be applying standard, repeatable, timely methods to test resistance in Varroa populations in the US and Canada. This will confidently determine if treatments are working, and provide tools and information to act quickly if resistance is developing. Because of Varroa’s historic ability to become treatment resistant, PAm is also funding several other projects to develop effective alternative tools and treatment options for Varroa.
The company that manufactures Apivar, Veto-pharma, has also been proactive about this concern. Last week at the international Apimondia conference, Veto-pharma offered a seminar to share information about the history and reports of resistance to Amitraz. They are helping researchers by sharing reported incidents of resistance, and giving financial support to PAm to fund these important projects.
You can view the slides from Veto-Pharma's presentation at Apimondia 2019 here.
There are other groups studying Amitraz efficacy, including Dr. Frank Rinkevich at the USDA-ARS Baton Rouge Bee Lab, and the Bee Informed Partnership also helps gather information about mite treatment efficacy in the field. By working together, we can hope for early detection and rapid response to resistance. Amitraz has been used to control cattle ticks for over 40 years, with very low occurrence of resistant ticks. As we hope for the best- that this treatment will remain effective for many decades, we can also prepare for the worst and support research to follow up on concerns about Varroa resistance to Amitraz. PAm is glad to support timely, relevant projects like this on behalf of beekeepers and the healthy bees we all rely on!
Article By: Danielle Downey,
Executive Director, Project Apis m.