Atypical EFB in Alberta

Atypical EFB in Alberta

By Alberta Agriculture and Forestry Bee Health Assurance Team

In recent months, the Alberta Agriculture and Forestry Bee Inspectors have seen a rise in European Foulbrood (EFB) cases. Testing performed by the National Bee Diagnostic Centre (NBDC) has shown that many of these cases are a new, more virulent and atypical form of EFB. In previous years beekeepers have often found that EFB clears up without intervention, however this atypical strain is more virulent and slow to clean up. Symptoms of EFB include a spotty brood pattern, as well diseased larvae which may be yellow, grey, brown or black in color. Larvae may also curl in a “C” shape at the bottom of the cell. In atypical cases, inspectors are seeing a wide range of infected larvae from very young to occasionally post-capping stage larvae. Most are discoloured, and the larvae are twisted or stretched in the cell.

If you suspect your colonies have EFB and have not recently been inspected, please take two clear photos of the diseased brood. One photo should show the entire frame and a second photo should be clearly zoomed in. Please email these photos to bee@gov.ab.ca. If the symptoms are consistent with EFB, you will be mailed a sampling kit with a pre-addressed return envelope, or an inspector will arrange a visit. More information on EFB management in Alberta is available in the February 2020 Bee News and at https://open.alberta.ca/publications/european-foulbrood