Researchers at Colorado State University and the University of Northern Colorado are working to develop an antiviral drug with the potential to fight West Nile, dengue and yellow fever viruses.
More work lies ahead to improve the effectiveness of the drug now that the researchers have confirmed it works in cells against several different viruses.

"We're in the process of testing these drugs against a number of different flaviviruses and trying to improve how well it works in animal models, so there's a lot more work to get it to the point where it would be used as an investigational new drug," one of the researchers, Brian Geiss, said. "However, this is an exciting new finding that has the potential to reduce the suffering caused by these serious pathogens."

Geiss is an assistant professor in CSU's Department of Microbiology, Immunology and Pathology. The other lead researcher is Susan Keenan, associate professor and director of the School of Biological Sciences at the University of Northern Colorado. Their initial findings appear this week online in the peer-reviewed Journal of Virology.

West Nile and dengue fever are vector-borne viral diseases – pathogens that can be transferred from an insect to a human - in a family of viruses known as the flaviviruses. These viruses are often life-threatening illnesses with few drugs or vaccines available and have the potential to be used as biological weapons.

More than 2 billion people are at risk globally of infection by dengue virus, and West Nile virus is endemic in 47 of the 48 lower United States. Dengue virus has re-emerged in southern Florida and Hawaii over the past few years. Worldwide, as many as 50 million dengue infections occur each year causing roughly 20,000 to 30,000 deaths.

Geiss and Keenan are developing a drug that can bind to a protein critical for viral replication and block the protein's function.

One of the molecules they found was able to reduce virus replication in cells by more than 1,000-fold.