LAMP-OSD Assay for Insect-Borne Diseases

Abstract

The distribution of vector-borne diseases such as Zika virus continues to expand, leading to epidemics across a variety of geographical locations, but monitoring the spread of these diseases for public health purposes is made difficult by a lack of instrumentation. With the assay we are developing and testing, there is no need for special equipment to perform PCR and gel electrophoresis.  Through carefully designed primers and probes, our method identifies nucleic acids and makes them visibly fluorescent using just an incubator and a diode. Thus, this assay will be able to detect and monitor the spread of insect-borne viruses and bacteria in the field in any location.  Using a Drosophila melanogaster system, Drosophila C Virus (DCV) and Drosophila X Virus (DXV) have been successfully visualized. Results of viral dynamics experiments to monitor the course of infection show that the proportion of DCV infected flies begins to decrease after 7 days post-infection, and the proportion of DXV infected flies begins to decrease after 20 days post-infection.  These results are fairly consistent with results from other methods of viral detection.  In the future, we are expanding the scope of the assay to include viral variants and the Drosophila bacterial endosymbiont Wolbachia pipientis.