Honors College Theses

Publication Date



Biology (B.S.B.)

Document Type and Release Option

Thesis (open access)

Faculty Mentor

Dr. William Irby


Canine heartworm disease is caused by the filarial nematode Dirofilaria immitis, which is transmitted by at least 25 known species of mosquito vectors. This study sought to understand which species of mosquitoes are present in Bulloch County, Georgia, and which species are transmitting canine heartworm disease. This study also investigated whether particular canine demographics correlated with a greater risk of heartworm disease. Surveillance of mosquitoes was conducted in known heartworm-positive canine locations using traditional gravid trapping and vacuum sampling. Mosquito samples were frozen until deemed inactive, then identified by species and sex. The mosquitoes were then either dissected under a microscope and/or set aside for detection of heartworm DNA using TaqMan Polymerase Chain Reaction (PCR). Species, sex, date collected, trap type, feeding status, and heartworm presence were recorded for each specimen in the lab. A primer specific to Dirofilaria immitis was used for TaqMan PCR. Shelter intakes at the Humane Society for Greater Savannah provided additional data on how heartworm affects dogs of varying demographics. Two species of mosquito, Culex quinquefasciatus (CQ) and Culex nigripalpus (CN), were identified as heartworm vectors in Bulloch County. No correlations between heartworm status and dog demographics were found; however, a more pertinent issue was discovered – the lack of publicly available data for heartworm status of companion animals.

Thesis Summary

This project has two main components: 1) to understand which species of mosquitoes are transmitting canine heartworm disease in Bulloch County, Georgia, and 2) to investigate whether certain demographics of dogs in Southeastern Georgia are more prone to the disease than others.