AC-DC Electropenetrography as a tool to quantify probing and ingestion behaviors of the yellow fever mosquito (Aedes aegypti) on mice in Biocontainment

Authors: VAUGHAN, LYNDSI - Tulane University; JAMESON, SAMUEL - Tulane University; WESSON, DAWN - Tulane University; SILVER, KRISTOPHER - Kansas State University; Mitzel, Dana; DOBEK, GEORGINA - Tulane University; LONDONO-RENTERIA, BERLIN - Tulane University

Submitted to: Comparative Medicine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/31/2023
Publication Date: 12/1/2023
Citation: Vaughan, L.D., Jameson, S.B., Wesson, D.M., Silver, K.S., Mitzel, D.N., Dobek,G.L., Londono-Renteria, B. 2023. AC-DC Electropenetrography as a tool to quantify probing and ingestion behaviors of the yellow fever mosquito (Aedes aegypti) on mice in Biocontainment. Comparative Medicine. 73(6):474-485. https://doi.org/10.30802/AALAS-CM-23-000037.
DOI: https://doi.org/10.30802/AALAS-CM-23-000037

Interpretive Summary: The recent rapid and geographically extensive emergence and re-emergence of several mosquito-borne diseases (Chikungunya virus, Zika virus, Bluetongue virus) has demonstrated the importance of these infections to animal and human health. The pathogens that cause these diseases are unique in that their survival depends on complex interactions between the virus, the mosquito vector, and the mammalian host. A detailed understanding of these interactions is important for understanding the transmission of these viruses as well as how novel interventions can disrupt this process. The natural transmission cycle of these viruses relies on the bite of the mosquito for the acquisition or inoculation of the virus. Electropenetrography (EPG) can elucidate different behaviors by recording the electrical signals generated during probing. However, the animal studies needed to examine transmission of these viruses is complicated by the need to work under biocontainment conditions. This study demonstrates the safe adaption of EPG to high biocontainment conditions using a mouse model.

Technical Abstract: A detailed understanding of mosquito probing and ingestion behaviors is crucial in developing novel interventions to interrupt the transmission of important human and veterinary pathogens, but these behaviors are difficult to observe as the mouthparts are inserted into the skin of the host. Electropenetrography (EPG) allows indirect observation, recording, and quantification of probing and ingestion behaviors of arthropods by visualizing the electrical waveform associated with these behaviors. The study of mosquito probing and ingestion behaviors has been limited to the use of human hands as host which is not suitable for pathogen transmission studies. Mouse models of mosquito-borne diseases are a widely used and indispensable tool in this research, but previous attempts to utilize direct current EPG to study mosquito probing behaviors on mice have been unsuccessful. Accordingly, the present study used alternating or direct current (AC-DC) electropenetrography (EPG) to observe the ingestion behaviors of adult Aedes aegypti mosquitoes on a mouse host in real time under BSL-2 containment conditions with enhanced BSL-3 practices. Our results show that waveform families previously identified during Ae. aegypti probing and ingestion on human hands were observed using 100 mV of AC at an input resistance (Ri) of 107 Ohms (') on CD1 mice. This work is a proof of concept for using mouse models for studying mosquito probing and ingestion behaviors with AC-DC EPG. In addition, these data show that the experimental setup used in these experiments is sufficient for conducting studies on mosquito probing and ingestion behaviors under BSL-2 containment conditions enhanced with BSL-3 practices. This work will serve as a foundation for using EPG to investigate the effects of pathogen infection on mosquito probing behaviors and to understand the real time dynamics of pathogen transmission.