American foulbrood

Definition

A highly contagious, globally distributed brood disease of honey bees (Apis mellifera) caused by the endospore-forming bacterium Paenibacillus larvae. Infection occurs when larvae ingest spores, which germinate in the gut and multiply, killing the host and converting the cadaver into a dark, glue-like scale that adheres tightly to the cell wall. The spores remain viable for decades, making the disease extremely persistent and difficult to eradicate from contaminated equipment.

Etymology

Example

Beekeepers in temperate regions routinely inspect brood combs for the characteristic sunken, greasy-looking cell caps and irregular brood patterns that signal American foulbrood; in many jurisdictions, detection triggers mandatory hive destruction by burning to prevent spore dispersal.

Synonyms

• AFB

Related Terms

• European foulbrood
• Paenibacillus larvae
• honey bee pathology
• brood disease
• foulbrood scale
• apiary sanitation

Usage Notes

Distinguished from European foulbrood (caused by Melissococcus plutonius) by the presence of long-lasting spores and the characteristic ropy, threadlike consistency of dead larval remains. The term is sometimes written without capitalization of 'foulbrood,' but 'American' is always capitalized. 'AFB' is widely used in regulatory and extension literature but should be defined on first use in formal writing. Because spores survive standard disinfection, infected colonies and equipment are typically incinerated rather than treated chemically.