Nisha Duggal. Courtesy of Virginia Tech.

West Nile virus, Usutu virus, Zika virus and St. Louis encephalitis virus are all transmitted by mosquitoes and cause a significant threat to human health. 

Nisha Duggal, an assistant professor of biomedical sciences and pathobiology in the Virginia-Maryland College of Veterinary Medicine, has recently received three R21 grants from the National Institutes of Health totaling $825,000 to combat the transmission of these diseases, develop therapeutics, and predict future disease in humans.

“Mosquito-borne viruses are emerging globally, with increasing host range and disease potential. With this funding, we are determining who is most at risk for transmission and looking to develop future vaccines and therapeutics,” said Duggal in a statement. She is also an affiliated faculty member of the Center for Emerging, Zoonotic and Arthropod-borne Pathogens and the Fralin Life Sciences Institute.

Duggal’s long-term goal is to understand how viral adaptation during emergence affects virus transmission and pathogenesis. Her interests involve emerging viruses, host-virus co-evolution, virus transmission, and immunity in birds.

With these grants, Duggal and her research team will tackle Usutu virus, West Nile virus and St. Louis encephalitis virus transmission and pathogenesis in mosquitos and birds; study Zika virus sexual transmission in humans; and use molecular virology and phylogenetic tools to predict future viral emergence and disease.

For West Nile and Usutu virus, Duggal is developing a reverse genetics system by transforming the viral RNA into DNA that can be more easily manipulated for experiments. Duggal hopes to discover cross-reactivity in immune responses to determine if future vaccines can be used for both viruses. The long-term goal is the development of therapeutics to reduce disease.

For Zika, Duggal and her team plan to use this grant funding to identify the infectious potential of Zika virus in semen and the window of time in which infection is possible between sexual partners. Upon successful completion of the proposed research, the anticipated impact of this work will be the identification of the cellular source of Zika virus in semen and the ability to assess and prevent the risk of Zika virus sexual transmission.

For all the viruses, Duggal and her team will study North American birds and mosquitoes to identify possible transmission cycles. The long-term goal of this project is to understand the factors that influence novel virus emergence in order to predict future outbreaks in humans.

She will partner with James Weger-Lucarelli at Virginia Tech and Angela Bosco-Lauth at Colorado State University