Date of Award:
Master of Science (MS)
Scott A. Bernhardt
Scott A. Bernhardt
Leishmaniasis is an understudied disease found predominantly in high heat and humidity areas. The disease is transmitted by sandflies which are blood-feeding, biting insects. There is currently no known vaccine for any form of leishmaniasis and treatment imposes a significant economic impact on already poor and marginalized populations, as well as severe, lingering side effects for afflicted individuals. Annually, there are millions of people around the world afflicted with a form of Leishmaniasis that is transmitted by species of sandflies. The primary sandfly population control method for over half a century has been indoor residual spraying using insecticides. The selective pressure from utilizing insecticides over such a long period has resulted in selection for resistance which requires an assay to monitor and identify these populations.
The goal of this thesis is to determine and assess insecticide susceptibility and resistance of the sandfly species, Phelebotomus argentipes. Research started by understanding the response of sandflies to particular insecticides of interest. This was completed by assessing levels of susceptibility of the P. argentipes colony to three insecticides which have been used extensively in India throughout the years. Susceptibility curves were developed to determine lethal concentration (LC) of insecticides capable of reducing populations by 50%, 75%, and 90%.
An amplification assay (Polymerase Chain Reaction) was optimized to specifically amplify genetic regions associated with insecticide resistance for P. argentipes sandflies. Whereas, another amplification assay (Loop-mediated Isothermal Amplification) was developed as an effective and rapid procedure for integrated pest management (IPM) professionals to assess the degree of insecticide susceptibility in field collected populations of P. argentipes sandflies. This rapid detection of field collected samples could allow IPM professionals to determine the degree of susceptibility of sandfly populations collected from afflicted areas. Thus, allowing the disease vector to be controlled in a more timely and effective manner.
Hennings, Shawna M., "Insecticide Susceptibility and Resistance Detection in Phlebotomus argentipes Sandflies (Diptera: Psychodidae: Phlebotominae)" (2022). All Graduate Theses and Dissertations, Spring 1920 to Summer 2023. 8665.
Copyright for this work is retained by the student. If you have any questions regarding the inclusion of this work in the Digital Commons, please email us at .