Melissococcus plutonius Can Be Effectively and Economically Detected Using Hive Debris and Conventional PCR

Area of Science:

• Apiculture and Bee Health
• Microbiology and Infectious Diseases
• Molecular Diagnostics

Background:

• European foulbrood (EFB) is a significant bacterial disease affecting honey bee colonies, caused by *Melissococcus plutonius*.
• Accurate and non-invasive diagnostic methods are crucial for managing EFB and maintaining honey bee populations.
• Current diagnostic approaches may require invasive sampling, potentially stressing colonies or leading to sample degradation.

Purpose of the Study:

• To develop and validate a DNA-based diagnostic method for European foulbrood using non-invasively collected hive debris.
• To compare the diagnostic performance of hive debris samples with traditional samples like honey and adult bees.
• To assess the reliability, sensitivity, specificity, and accuracy of the PCR-based method for EFB detection.

Main Methods:

• Development of a DNA isolation protocol and conventional PCR assay for *M. plutonius*.
• Non-invasive collection of hive debris using paper sheets on bottom boards.
• Field trials involving honey bee colonies with and without clinical EFB symptoms.
• Application of Bayes statistics to evaluate diagnostic parameters across different sample types (honey, hive debris, adult bees).

Main Results:

• The conventional PCR method demonstrated high reliability, with 100% accuracy at 6.7 × 10³ CFU/g of debris.
• Sensitivity and specificity varied by sample type: adult bees (1.000, 0.833), honey (0.867, 0.842), and hive debris (0.714, 0.800).
• Hive debris analysis showed high predictive values and real accuracies, comparable to other sample types, indicating its diagnostic potential.

Conclusions:

• Hive debris is a viable and effective matrix for the non-invasive monitoring of European foulbrood in honey bee colonies.
• The developed PCR method provides a reliable tool for early detection and management of EFB.
• Non-invasive sampling using hive debris offers a practical and less disruptive alternative for routine bee health surveillance.