title: Idiopathic brood disease syndrome and queen events as precursors of colony mortality in migratory beekeeping operations in the eastern United States.
abstract: Using standard epidemiological methods, this study set out to quantify the risk associated with exposure to easily diagnosed factors on colony mortality and morbidity in three migratory beekeeping operations. Fifty-six percent of all colonies monitored during the 10-month period died. The relative risk (RR) that a colony would die over the short term (∼50 days) was appreciably increased in colonies diagnosed with Idiopathic Brood Disease Syndrome (IBDS), a condition where brood of different ages appear molten on the bottom of cells (RR=3.2), or with a "queen event" (e.g., evidence of queen replacement or failure; RR=3.1). We also found that several risk factors-including the incidence of a poor brood pattern, chalkbood (CB), deformed wing virus (DWV), sacbrood virus (SBV), and exceeding the threshold of 5 Varroa mites per 100 bees-were differentially expressed in different beekeeping operations. Further, we found that a diagnosis of several factors were significantly more or less likely to be associated with a simultaneous diagnosis of another risk factor. These finding support the growing consensus that the causes of colony mortality are multiple and interrelated.
authors.affiliation: Department of Entomology, Plant Science Building, University of Maryland, MD 20742, USA. dennis.vanengelsdorp@gmail.com
authors.forename: Dennis
authors.initials: D
authors.lastname: vanEngelsdorp
authors.forename: David R
authors.initials: DR
authors.lastname: Tarpy
authors.forename: Eugene J
authors.initials: EJ
authors.lastname: Lengerich
authors.forename: Jeffery S
authors.initials: JS
authors.lastname: Pettis
mesh_terms: D000818:Animals; D056630:Beekeeping; D001516:Bees / Q000382:microbiology / Q000469:parasitology / Q000502:physiology* / Q000821:virology; D056631:Colony Collapse / Q000453:epidemiology / Q000382:microbiology* / Q000469:parasitology* / Q000821:virology; D011157:Population Dynamics; D012306:Risk; D014481:United States / Q000453:epidemiology