|MAHDI, OSAMA - North Dakota State University|
|GREENLEE, KENDRA - North Dakota State University|
|ROSE, ETHAN - Iowa State University|
|Rinehart, Joseph - Joe|
Submitted to: Journal of Apicultural Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/10/2021
Publication Date: 5/18/2021
Citation: Mahdi, O.S., Greenlee, K.J., Rose, E., Rinehart, J.P., Smith, D.J. 2021. The sporicidal activity of chlorine dioxide gas on Paenibacillus larvae spores. Journal of Apicultural Research. https://doi.org/10.1080/00218839.2021.1920761.
Interpretive Summary: American Foulbrood Disease devastates honey bee hives by infecting and propagating in developing honey bee larvae. Although the disease has been characterized for decades, treatment strategies outside of burning infected hives do not exist. This study was conducted to determine whether chlorine dioxide gas kills spores of the honey bee pathogen, Paenibacillus larvae, the causative agent of American Foulbrood Disease. Chlorine dioxide was highly effective at preventing germination of spores suspended in water and spores adhered to pine, steel, and bees wax. Killing efficiency was related to dose and exposure time. Further experiments are needed to determine the effectiveness of chlorine dioxide gas sanitation of bee boxes and bee keeping equipment contaminated with pathogen spores.
Technical Abstract: American foulbrood disease (AFB) is an economically important, reportable bacterial infection of honey bees (Apis mellifera) caused by the spore-forming pathogen Paenibacillus larvae. Currently there are no viable measures for treating P. larvae infected hives other than incineration. The objective of this study was to determine the activity of chlorine dioxide (ClO2) gas against P. larvae spores. Sporicidal efficacy was dependent on treatment time and gas concentration with effective ClO2 concentrations of 645 ng/ml for 30 min, 195 ng/ml for 1 h, 21 ng/ml for 2 h, or 16 ng/ml for 4 h. Treatment of surfaces with 230 ng/ml ClO2 for one h or 195 ng/ml ClO2 for 2 h completely inactivated P. larvae spores.