This post is what is planned to be a monthly series bringing your attention to the pests and diseases and other problems which can weaken or kill colonies of honey bees.

The idea behind this initiative was a severe case of sacbrood which was found by one of our members in one of his hives.

What is sacbrood?

Sacbrood is a brood disorder caused by infection caused by a virus called Morator Aetatulas.

Larvae infected by the virus fail to pupate and die.

In the final stage the larvae turns black.

Bees will uncap and remove dead larvae – cells with perforated cappings should always be investigated.

In the final stages infected larvae can be seen their backs on the lower wall of their cells with their heads out in the shape known as “Chinese Slipper”.

The dead larvae can be removed using a matchstick – removing the larvae can reduce the spread of the virus.

Comb can be reused as the virus  becomes non-infectious in a few weeks.

Infection is usually slight although it can spread throughout the hive causing widespread loss of larvae.

There are no treatments available for sacbrood.

Further reading

Beebase