Development and validation of a novel field test kit for European foulbrood

European foulbrood (EFB) is a serious and widespread disease of honey bee larvae. It is a notifiable disease in the United Kingdom under existing legislation, so colonies must be officially screened for signs of disease. The current study developed a rapid and sensitive test to diagnose EFB in the field. A monoclonal antibody, highly specific for its causative agent, Melissococcus plutonius, was produced, optimised and incorporated into a Lateral Flow Device (LFD). Laboratory trials of LFDs found them to be very effective, detecting M. plutonius in 96-100% (n = 137) of EFB-infected samples with no cross-reactivity with other bee brood pathogens. Field validation data was equally robust: correct diagnoses were obtained on 96% (n = 184) of samples subjected to LFD-testing on site; false positives were rare (similar to 1%). EFB LFDs are now issued to all Appointed Bee Inspectors in England and Wales as the sole diagnostic tool for routine confirmation of M. plutonius infection in the field, allowing much more efficient disease detection and control.