Foulbrood: European and American

The two foul broods are so named because they affect larvae in a similar way, leaving them discoloured, shrivelled, and often foul-smelling. But they are actually caused by two completely different bacteria.

European Foulbrood is more common and less severe; a hive can overcome it with intervention (reduce space and feed!) most of the time.

American Foulbrood, on the other hand, is not one to mess around with. In most jurisdictions, you are required to report American Foulbrood and destroy the hive.

But how can you tell them apart?

You can purchase diagnostic test kits from a bee supply shop. They are unique to each bacteria so it's probably best to get both.

You can also do a rope test. Choose a cell with a waxy, sunken capping and stick a small stick through the capping. Swirl it around in the cell for a few seconds. When you slowly withdraw the stick, if the 'goo' forms a rope, you might be looking at American Foulbrood.

Most provinces/states will also have a bee lab that can analyze samples.

NOTE: If you suspect American Foulbrood, contact your regional/state inspector immediately!

The Honeybee Health Coalition has produced a fantastic resource called Managing Foulbrood that is a must read for beekeepers. It is only 6 pages long and packed with all you need to know about these two brood diseases.

You can download a copy of their resource here.