How is Chalkbrood typically transmitted between colonies?

Chalkbrood is a fungal disease affecting honeybee larvae, caused by the pathogen Ascosphaera apis. The primary mode of transmission occurs when spores from infected brood or tools used in beekeeping are transferred between colonies. Beekeepers can inadvertently spread the disease by moving frames of brood that contain the spores or by using contaminated tools and equipment without proper sanitation.

Natural swarming is not a primary method of transmitting Chalkbrood, as swarming typically involves healthy bees leaving the colony with little to no exposure to the spores. Similarly, while wind can carry fungal spores in the environment, it is not a direct vector for transmission between colonies, as the spores require contact with larvae to infect. Lastly, contaminated honey poses minimal risk for Chalkbrood transmission, as the disease specifically targets larvae rather than being spread through honey consumption by adult bees. Thus, the role of beekeepers in spreading the disease through practices that involve equipment and brood transfer is the most significant factor in the transmission of Chalkbrood between colonies.