SBV or Sacbrood Virus (Morator aetatulas) often appears during spring or colony buildup and causes larval death. The pupa fails to pupate and has a “shrunken head” appearance. When you see perforations in the sealed brood with the infected larvae inside, the perforation is usually choppy or jagged indicating a problem. If the SBV pupa is totally open, the capping has been completely removed by bees and the pupa is most likely greyish-yellow to brown and starting to dry out. When removed the pupa looks similar to a slipper or canoe. Infected adult bees will have decreased life spans.
Symptoms:
• Perforated sealed brood, pupa present with undeveloped head.
• Color ranges from pearly white to pale yellow to brown and eventually to black, when it is in scale form it is brittle and easily removed.
Treatments:
The only known treatment is to re-queen.
SBV (Sacbrood Virus)