Heart Worm Project: 

Mosquitoes are globally recognized as vectors of numerous infectious diseases, including parasitic, viral, and bacterial pathogens that pose significant threats to both human and animal health. Among these, Dirofilaria immitis, the causative agent of heartworm disease, is a filarial nematode transmitted through the bite of infected mosquitoes. Heartworm disease primarily affects canines but can also infect felines and other mammalian hosts, leading to potentially fatal cardiopulmonary complications if left untreated.

The southeastern United States, particularly South Carolina, continues to experience a disproportionately high burden of heartworm disease. According to the American Heartworm Society’s 2022 Heartworm Incidence Map, South Carolina remains among the top three states in the nation for heartworm prevalence, with veterinary clinics reporting an average of 25 or more heartworm-positive cases per year.  This represents a significant public and veterinary health concern, especially in regions where mosquito populations are abundant and environmental conditions favor year-round transmission.

In response to this ongoing threat, our research initiative has focused on the development of a molecular diagnostic assay capable of detecting D. immitis DNA in mosquito vectors. The primary objective of this project is to establish a reliable, sensitive, and specific method for early detection of heart worm presence in local mosquito populations, thereby enabling proactive surveillance and targeted intervention strategies.

To achieve this, we selected primer sets from previously published literature that target conserved regions of the D. immitis mitochondrial genome, specifically the cytochrome c oxidase subunit I (COI) gene and the 12S ribosomal RNA (12S rRNA) gene. Primer sequences were validated using the NCBI BLASTn tool to confirm their alignment exclusively with D. immitis sequences and to eliminate potential cross-reactivity with non-target organisms.

Over the past year, we have optimized polymerase chain reaction (PCR) protocols using Heart worm positive blood samples from local vet clinics. Preliminary laboratory trials have demonstrated successful detection of D. immitis DNA in many communities. More field testing is currently underway, utilizing mosquito specimens collected from high-incidence areas within Horry County, South Carolina.

The successful implementation of this diagnostic assay holds significant promise for enhancing community-level surveillance of heart worm transmission. By identifying infected mosquito vectors prior to the onset of clinical disease in companion animals, this tool can inform public health responses, guide veterinary preventative care, and ultimately reduce the incidence of heart worm disease. Furthermore, the dissemination of findings through public education initiatives will empower pet owners with knowledge about the risks of heart worm and the importance of year-round preventative measures.  This project represents a critical step toward integrating molecular diagnostics into vector-borne disease monitoring frameworks for community level awareness. Its success could serve as a model for similar efforts in other endemic regions, contributing to broader efforts in zoonotic disease prevention and control.

Hook Worm Project

The escalating prevalence of canine hookworm (Ancylostoma caninum) infection in the Southeastern United States poses a significant challenge to animal welfare organizations and presents a localized public health risk. In collaboration with local animal shelters, the Hookworm Project was initiated to develop a high-specificity molecular assay capable of detecting A. caninum genetic material directly in environmental samples. Utilizing Polymerase Chain Reaction (PCR) targeting conserved mitochondrial genes, the team has established a reliable screening method for both soil and water matrices. Current efforts are focused on environmental surveillance across Horry County and shelter facilities to accurately map the disease’s prevalence and inform evidence-based parasite control strategies.

Canine hookworm, caused primarily by A. caninum, is a growing concern, particularly within high-density animal populations such as those maintained by animal shelters. The shared use of outdoor facilities creates an environment conducive to continuous transmission. A major complicating factor is the parasitic organism’s resilience; eggs and infective larvae can persist in soil for prolonged periods, remaining infectious even after source animals have been adopted and removed from the premises.

The Hookworm Project was conceived to meet this critical need by developing a direct environmental diagnostic test.  To achieve high sensitivity and specificity for A. caninum detection, a genetic screening protocol based on Polymerase Chain Reaction (PCR) was developed. This molecular assay is designed to amplify unique signature sequences within the hookworm genome. The primary targets selected for amplification are segments of two key mitochondrial genes: Cytochrome Oxidase Subunit 1 (Cox1) and Cytochrome b (Cytb)

The project has transitioned into an active surveillance phase to accurately determine the local ecological burden of A. caninum. This effort involves two primary sampling arms: Community Water Sampling: Collection of water samples across Horry County to assess general environmental dispersal and potential sources of widespread contamination. Targeted Animal Shelter Soil Sampling: Collection of soil samples from the communal outdoor enclosures of collaborating animal shelters, which are considered high-risk transmission hotspots.

Data gathered from this surveillance will be crucial for establishing baseline prevalence rates and identifying spatial clusters of contamination. This information is intended to be used by shelter management to: (1) Prioritize areas for intensive chemical or heat treatment for parasite remediation, (2) Establish mandatory rotation schedules for shared outdoor runs, (3) Refine internal veterinary protocols for preventative treatment and deworming.

This research funded by: Summer Undergraduate research Fellows program

This research funded by: SCINBRE

This research funded by: GUPTA Research Fellows

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Disease Fact Sheets

Heart Worm Fact Sheet

Hook Worm Fact Sheets