Bees are one of the most important species responsible for pollinating about one-third of the world's food supply, and their contribution to the United States alone is $ 15-20 billion annually. The sharp decline in honey bee colonies in the world and especially in the US has created a greater burden on future agricultural pollination and food security. Parasites are one of the factors affecting the decline of the bee population, and Nosema ceranea and Nosema apis are some of the most common. Nosema apis infection can cause dysentery symptoms and honeybee thawing at the hive entrance, but Nosema ceranae infection does not show any physical symptoms. This "quiet killer" of honey bees infects the bees, drones and bees, and can even cause colony collapse.
Currently, the only approach to diagnosing this disease is precisely with the detection of parasite spores using a light microscope. However, this traditional testing is done in laboratory settings and requires expert work. Therefore, beekeepers should send local samples to a remote laboratory to get an accurate diagnosis that is time consuming and costly.
Researchers at UCLA Samuel's School of Engineering in collaboration with Barnard College's Biology Department have developed a mobile phone microscope that enables quick and automated clarification of Nosema spores in honey bees in field settings. This mobile and cost-effective platform, weighing just 0.8 pounds, consists of a smartphone-based fluorescence microscope, customized in a smartphone application and an easy-to-perform sample preparation protocol that allows the spores of bee parasites to be tagged even in the field.
UCLA Chancellor Professor Aydogan Ozcan and UCLA Associate Director of the NanoSystems Institute in California led the study in collaboration with Jonathan Snow, Associate Professor of Biology at Barnard College (NY) and Hatice Ceylan Koydemir. , Senior Researcher UCLA. The study was published Lab on chips, Royal Chemistry Society Magazine (UK).
Diagnosis of the disease with this new platform involves sample preparation when honey bee tissue is removed and midguts are removed, followed by a small amount of stain to fluorescently label parasite spores. A drop of prepared solution is then placed on the glass slide, which is then placed under the microscope of the mobile phone for analysis. The smartphone then captures the sample image and sends it to the computer for automated analysis to quickly detect the number of spores sent back to the user in less than 90 seconds.
The researchers tested the performance of this mobile platform using field samples, and determined that the device was able to detect parasite concentrations in the bee below the threshold required to recommend treatment for Nosema parasites. Therefore, this mobile phone corresponds to the required detection sensitivity to determine the treatment.
"Bee welfare is a very important issue in global food security and ecosystem stability. There are many factors that affect the rapid decline in bee populations, and parasitic infections play an important role. The developed mobile device opens the way to address this new problem. known, it is the first and only existing platform for the determination of Nosema spores in field settings. "said Ozcan.
The study was supported by the North American Pollinator Protection Campaign, the National Science Foundation Engineering Research Center (ERC) and the Howard Hughes Medical Institute (HHMI).
A tiny parasite can contribute to the reduction of colonies of honey bees by infecting larvae
Jonathan W. Snow et al. Honey bees for rapid imaging, detection and quantification of Nosema ceranae spores using a cellular fluorescence microscope, t Lab on chips (2019). DOI: 10.1039 / C8LC01342J