Practical Guide: 2.2 European foulbrood

European foulbrood is a bacterial disease of the brood in which the larvae usually die before capping. The official SSA/BGD checklist 2.2 describes typical signs such as patchy brood, yellowish to brown-black larvae, the match test, and a characteristic odor. It also specifies that this is a notifiable epizootic disease and that the apiary inspector must be called immediately.

Official Practical Guide (BGD / SSA) – Summary

Practical Guide: 2.2 European foulbrood (V 2402)

• Objective: The practical guide presents the appearance, diagnosis, procedure, prevention, control, and eradication of European foulbrood.
• General description: European foulbrood is a bacterial disease. The bacteria can remain active for several months or even years; adult bees are not infected, but they can carry the pathogen.
• Transmission: The disease can be transmitted from one colony to another by bees, in particular during robbing, drifting, and by drones, as well as by the beekeeper, notably during the exchange of frames, the uniting of colonies, feeding with infected or imported honey, reuse of contaminated equipment, or use of insufficiently sterilized wax.
• Diagnosis: The practical guide mentions patchy brood, flaccid yellowish to brownish larvae, larvae lying upside down or in irregular positions in the cells, an often sour or putrid odour, a viscous mass producing only a short thread in the matchstick test, as well as dark brown to black larvae that can be removed easily.
• Important: This is a notifiable epizootic disease. The services of the bee inspector (AO IR) must be called in immediately.
• Prevention: The document recommends in particular regularly checking the brood pattern, eliminating weak colonies, avoiding hypothermia of brood frames, ensuring sufficient stores, preventing robbing, not feeding with honey from outside the apiary, controlling varroa according to the concept, and renewing frames regularly.
• Control: There is no remedy capable of curing a colony of European foulbrood. Colonies affected by the disease are sulphured by the bee inspector.
• Eradication: The instructions of the bee inspector must be followed to the letter. Dead bees as well as brood and feeding frames must be hermetically sealed and incinerated; on the order of the cantonal veterinarian, colonies without clinical symptoms may be partially sanitized using the open or closed artificial swarm method.

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Summary prepared on the basis of Practical Guide 2.2 (V 2402). Last checked: 01/2026.

See also:

• Practical Guide: 2 Diseases and pests
• Recognizing bee diseases
• Bee health guide
• Practical Guide: 4.1 Hygiene
• Practical Guide: 4.7.2 Destroying colonies
• Practical Guide: 1.4.2 Artificial swarm