How can European Foulbrood be identified?

European Foulbrood (EFB) is a bacterial disease affecting honeybee larvae, characterized by specific symptoms and signs. One of the primary indicators for identifying EFB is darkened larvae. In the early stages of the disease, larvae may appear creamy or white; however, as the disease progresses, the infected larvae change color to a darker hue, often resembling what is referred to as "coffee color" when they are dead. This darkening occurs as the larvae die and start to decompose, making it a key diagnostic feature of EFB.

While other symptoms such as sunken cells, white trachea, or visible mites may occur in hives, they are indicative of different conditions or diseases. Sunken cells can occur due to various factors, including malnutrition or other diseases, and are not specific to EFB. White trachea is not a typical symptom associated with EFB; instead, it indicates a different health issue. Mites, particularly Varroa mites, are a significant pest in beekeeping but do not indicate EFB directly. Therefore, identifying the darkened larvae is crucial in diagnosing European Foulbrood effectively.