Affected hosts
- Apis mellifera
Ascosphaerosis by Ascosphaera apis
Chalkbrood
Fungal brood disease that turns dead larvae into white or dark mummies resembling small chalk fragments.
Agent
Ascosphaera apis
Legal status
No
Signs and symptoms
Brood
- White, grey, or black mummies
- Irregular brood
- Mummies on the floor or at the hive entrance
Colony
- Reduction in viable brood
- Weakening if persistent
Diagnosis and confirmation
Field methods
- Visual identification of typical mummies
Laboratory methods
- Microscopy or culture when needed
Control and prevention
Good practices
- Improve ventilation
- Reduce humidity
- Adjust hive space to colony strength
- Remove heavily affected combs
Prevention
- Adequate ventilation
- Strong colonies
- Comb renewal
- Hygienic selection
Monitoring
Indicators
- Number of mummies
- Brood pattern
- Humidity
Frequency
- During brood inspections, especially in cold and humid periods