How can American and European foulbrood be differentiated?

Differentiating between American Foulbrood (AFB) and European Foulbrood (EFB) primarily relies on the characteristic odor and symptoms exhibited by the infected larvae.

American Foulbrood is associated with a distinctive putrid smell and typically presents signs like sunken, dark, and greasy-looking larvae that often lie in a twisted position. In contrast, European Foulbrood does not have the same strong odor; the affected larvae appear yellow to brown and are often more less developed and watery in appearance.

Recognizing these specific characteristics—odors and the condition of the larvae—allows beekeepers to identify which type of foulbrood is present in the hive, leading to appropriate management and treatment strategies.

While hive location, color of the larvae, and presence of bees can provide context in terms of a broader understanding of bee health, they do not serve as reliable indicators for distinguishing between AFB and EFB specifically. The key to identification lies in the odor and visual symptoms associated with each disease.