Development of Diagnostic to Detect Dog Heartworm in California Mosquitoes

Dog heartworm disease is caused by Dirofilaria immitis, a roundworm parasite that is transmitted from one animal to another by a mosquito vector. Dog heartworm can cause several fatal effects in dogs and cats including severe weight loss and cardiac issues. Since the mosquito is the main vector that spreads this parasite, it is important to control local mosquito populations to reduce the number of infections. However, it is currently unknown which mosquito species serve as primary vectors of D. immitis in California. The purpose of this research is to develop a molecular assay to efficiently detect and differentiate the parasite species D. immitis from other roundworm parasites in mosquito vectors. This will allow us to characterize the infection prevalence of D. immitis in local mosquito populations and provide the first step in determining the ability of different mosquito species to transmit the parasite. To accomplish this goal we will design general primers that amplify either the cytochrome c oxidase subunit I (COI) or 5S/28S DNA segment from common filarial parasites in the area. Specific parasites will be differentiated based on the melting curve of the PCR product, a feature that depends on both length and composition of the DNA sequence. In the near future, this assay will be used to test field-caught mosquitoes for the presence of D. immitis to determine which mosquito species should be targeted to help control this disease in California