Research Summary
Citation: Roetschi, A., Berthoud, H., Kuhn, R., Imdorf, A. (2008). Infection rate based on quantitative real-time PCR of Melissococcus plutonius, the causal agent of European foulbrood, in honeybee colonies before and after apiary sanitation. Apidologie 39: 362-371.
Brief Description: The occurrence of European Foulbrood (EFB) in Switzerland's honey bee colonies has increased from about .1-.6% in the 1960s to 1.5% in 2006. The rise in cases has been constant since 1999. EFB is a notifiable disease in Switzerland and requires sanitation without the use of antibiotics. This study investigated the efficacy of sanitation, which in this case included burning every infected and weak colony.
Colonies with and without symptoms of EFB were studied at 11 apiaries, and a total of 114 hives. Colonies were visually checked for clinical symptoms before and after sanitation and DNA was used in a PCR technique to sample adult bees for the bacterium which causes EFB, Melissococcus plutonis.
Implications: The PCR technique showed that bees collected from the brood nest area were about 20 times more infected with the bacteria then those collected at the flight entrance. This was noted to be most likely due to the fact that brood nest bees are cleaning cells and ingesting more of the bacteria. The PCR technique was determined to be more sensitive to detecting EFB then visual inspections. The authors showed that sanitation was less effective as determined by visual surveys of apiaries, due to the increased sensitivity of the PCR technique. One year after sanitation, the bacterium responsible for EFB, was present in 5 out of 8 apiaries, leading the authors to conclude that sanitation measures tested are ineffective for EFB control.
summary/review by Michael Wilson, University of Tennessee
Bee Informed Partnership