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USDA Disease Diagnostics
By: Jay Evans
This month celebrates some great American stories. For me, I am most proud to be part of a longstanding U.S. Department of Agriculture tradition of research and diagnostics for bees. The USDA’s Bee Disease Diagnostic Service (BDDS) is alive and well and ably run by Mr. Samuel Abban. Historically, about 2,000 bee samples are sent in annually, evenly split between brood and adult worker bee samples. Around half of these samples come directly from beekeepers, with the rest coming from inspectors and other members of the Apiary Inspectors of America. An overview of this free service is available here: https://www.ars.usda.gov/northeast-area/beltsville-md-barc/beltsville-agricultural-research-center/bee-research-laboratory/docs/how-to-submit-samples/. Or simply search “bee disease diagnostic service” for details.
The BDDS has provided rapid determination of American foulbrood disease (AFB) for inspectors and beekeepers for decades, no doubt decreasing the impacts of AFB in U.S. apiaries. The BDDS also diagnoses European foulbrood (EFB), chalkbrood, sacbrood, and symptoms of less-common brood diseases. Adult bees are treated to mite counts, nosema spore counts and, sporadically, checks for the now-rare tracheal mites. Like a good detective, Sam also notes signs of other colony threats, ranging from deformed wings to hive beetles, and leverages the field descriptions submitted alongside samples. While these reports are timely for submitters, the BDDS also allows for a historical view of bee threats in the U.S. USDA Researcher Mohamed Alburaki, and Sam, have led extensive analyses of patterns of bee disease over the years, including a freely available overview (Alburaki, M., Abban, S.K., Evans, J.D. Chen, Y.P. (2025) A thirty-two-year (1984–2015) longitudinal analysis of honey bee disease and pathogen prevalence in the USA. Apidologie 56, 60. https://doi.org/10.1007/s13592-025-01187-8). These analyses show trends in bee disease, including the expansion of European foulbrood, and of nosema disease with the spread of Nosema (Vairimorpha) ceranae. They also give each state its own running tally of bee disease. Results for several leading states have been published in Bee Culture in recent years and the raw data behind these analyses can be retrieved from several Alburaki publications.
Given the 140-year history of USDA bee disease work, it is helpful to see how we arrived at the present. USDA had a ‘Division of Entomology’ soon after the Agency’s birth in 1862. Like the current USDA’s Agricultural Research Service, this Bureau gave considerable attention to crop pests, while also devoting some effort to bees. The very first Report of the Commissioner of the newly formed USDA came out in January of 1863 (https://www.govinfo.gov/app/details/SERIAL SET-01168_00_00-002-0078-0000), with scant mention of bees across its 632 pages. Nevertheless, there was a hint of challenges to crops and bees “the bee moth and the curculio are instances of the fact that nearly all the products of the farm have their enemies”. Despite the ongoing Civil War, this Report had great optimism for the future of U.S. farming, i.e., “Starting in the first period ending in 1830 with an annual average of fifty millions of dollars, the surplusage of agricultural production after feeding eleven millions of people, American farmers have extended their operations till a population little less than threefold those numbers is fed upon the milk and honey and the wine and oil of a fruitful land, and a surplus is still shown not threefold, but sixfold, one hundred percent, greater than the increase in population. In view of facts so inspiring well may Bryant exclaim: “O country I marvel of the earth, 0 realm to sudden greatness grown.”
Honey bees received their due in the 2nd Commissioners Report in January, 1864 (https://www.govinfo.gov/app/details/SERIAL SET-01196_00_00-002-0091-0000), notably in a 17-page treatise by Richard Colvin (Baltimore, MD), pages 530-547. Colvin covered tips of the beekeeping trade (cribbed largely from Reverend L.L. Langstroth’s The Hive and the Honeybee) and debates over the merits of importing Italian bees to the U.S. He does give another nod to the bee moth “the moth, which is generally regarded as the greatest enemy to bee culture, seldom attacks, and never successfully overcomes, a populous colony”, but fails to note other biological threats. USDA scientists started bee research soon after, with the work of Special Agent Nelson McClain from 1885-1887 in Illinois (focused on bee breeds and arsenic poisoning). Frank Benton was hired to focus on bee culture in Washington, DC in 1891, forming the first dedicated ‘bee lab’ there. Benton then hired both Everett Phillips and Gershom Franklin White. Phillips and White wrote “Historical notes of the causes of bee disease” as a USDA bulletin in 1912 (https://archive.org/details/historicalnotes00phil/mode/2up), discussing early insights from Bahr to Zander. Phillips took on leadership of the Bee Division from 1906 to 1924, shepherding a move to the Maryland suburbs that was culminated by his successor, James L. Hambleton, with the establishment of the Beltsville Bee Research Lab in 1937 (known under a variety of formal names but thereafter supporting a crew of bee scientists). Hambleton stayed on as Lab Head until his retirement in 1958.
The Bee Disease Diagnostic Service was defined from 1905 onwards by G.F. White, a worker bee who carefully explored diseases of brood and adults. White formally described the bacterial cause of American foulbrood (AFB) in 1907 (https://www.govinfo.gov/app/details/GOVPUB-A-c5c1c56628388dc68610718bafffde00) and European foulbrood (EFB) in 1912 (https://www.govinfo.gov/app/details/GOVPUB-A48-3364ea4cbbec452e0e8e4f8132d4ba47). AFB was a slam dunk of sorts, but resolving the cause/s of EFB, 30 years after initial work in England on this disease, proved more complicated. After careful experimentation, White downgraded the roles of several bacteria observed in symptomatic larvae, including Bacillus alvei and Streptococcus apis. He instead described a new species, Bacillus pluton, as the primary agent behind EFB. Even here, he hedged his bets, writing “this organism is an unusual one and the classification has not yet been definitely determined. The generic term “Bacillus,” therefore, may and probably will be changed later.” In 1919, White highlighted the impacts of nosema disease (https://dn721704.ca.archive.org/0/items/nosemadisease780whit/nosemadisease780whit.pdf) and continued to write about bee diseases into the 1920’s, while also providing definitive diagnoses for the country.
AFB and EFB remained the biggest threats to beekeeping for a century, despite the tracheal mite scare of the 1910’s (not realized in the U.S. for 70 more years thanks to biosecurity measures). Successors to Hambleton, most notably Hachiro Shimanuki, made sure that the brood diseases were not forgotten at USDA, even as new threats emerged. Indeed, the BDDS remains the definitive diagnostic lab for foulbrood, a service to beekeepers large and small. If you suspect brood disease in your colonies, or want a post-collapse look at your adult worker bees, Samuel Abban is ready and waiting for your samples.
