Yale scientists have successfully immunized mice against the West Nile virus, raising hopes that a vaccine for humans against the mosquito-borne infection may be possible.

Researchers from the Yale School of Medicine and the Connecticut Agricultural Experiment Station in New Haven genetically engineered a protein in the virus, which was then injected into uninfected mice. Immunization with the vaccine provided complete protection for the mice against West Nile virus.

Study director Erol Fikrig, an associate professor of medicine in the Department of Epidemiology and Public Health, said the vaccine is an important step in combating the emerging disease.

“Its seriousness as a public health threat is not fully known yet,” Fikrig said. “If the vaccine proves necessary, its development will be valuable.”

The researchers said the protein used to make the vaccine could potentially be used to develop a diagnostic test for the virus.

West Nile virus was first seen in humans in the United States in 1999, and 10 related deaths have been reported to date in the United States. There is currently no cure for West Nile virus, although infection does not generally cause serious harm.

–Yale Daily News