This is the seventh short news article written by students, during the professional development class of Spring 2025, about each other's research.
Quinn Hankinson
Student Spotlight: Quinn Hankinson
By Marie Muniz
Mosquitoes are perplexing creatures. One bite from a female Aedes aegypti mosquito doesn’t just cause a red, itchy bump on a human’s arm, it has the potential to transmit the dangerous dengue virus, which causes dengue fever in humans. Dengue fever affects over 350 million humans annually, a severe illness that sometimes leads to death. Researchers at Penn State are using vector control methods to help prevent transmission of dengue virus.
“One of the most promising methods for vector control is the use of the bacteria Wolbachia pipientis,” says Quinn Hankinson, a graduate researcher in the Department of Entomology and Center for Infectious Disease Dynamics at Penn State.
Wolbachia is a naturally occurring bacteria that lives inside insects but that is notably absent in important mosquito vectors of viruses. Researchers have discovered that when Wolbachia is artificially introduced into mosquitoes, it has the amazing ability to reduce dengue virus growth inside the mosquito. This process, known as “pathogen blocking,” reduces the ability of mosquitoes to transmit the virus to humans. Since the bacteria can be passed down to future generations of mosquitoes, countries Australia, Mexico, Singapore, and Thailand, along with communities in California and Texas, have been strategically releasing Wolbachia-infected mosquitoes to replace natural populations and help combat the spread of dengue.
How Wolbachia prevents the growth of viruses in mosquitoes is complex and not completely understood.
“Factors such as Wolbachia strain, mosquito and virus genetic diversity, cellular competition, and innate immune system responses in the mosquito all contribute to Wolbachia-mediated pathogen blocking,” explains Hankinson.
Vector biologists have been investigating the bacteria’s ability to reduce dengue virus replication for over a decade. The Elizabeth McGraw lab group at Penn State has identified a candidate gene that may play a key role in Wolbachia's pathogen-blocking ability.
Until recently, researchers were unable to genetically modify Wolbachia, so there was no way to gather data on the functions of Wolbachia genes. Using a method pioneered by another research group, Hankinson will target and reduce the activity of the candidate gene in Wolbachia to assess the ability to interfere with the growth of dengue virus. If the candidate gene is indeed responsible for blocking dengue, decreasing its expression should increase dengue virus replication and transmission.
“It is absolutely crucial that we understand how Wolbachia is able to limit vectorial capacity in disease-spreading mosquitoes,” says Hankinson. This research comes at a time when there is still no cure for dengue virus. Hankinson explains, “Traditional efforts at controlling mosquitoes fail to keep up with factors like growing insecticide resistance and climate change; Wolbachia is one of our best bets at controlling the spread of devastating mosquito-borne diseases.”
Quinn Hankinson is an MS student in Beth McGraw’s research group in the Department of Entomology at Penn State University. This article is based upon work supported by the National Science Foundation Graduate Research Fellowship Program under Grant No. DGE1255832.
