Nasal vaccine delivery conquers West Nile virus in fewer doses

Researchers at Duke University have shown in early tests that a nasal vaccine for West Nile virus is effective in mice after two doses as opposed to the traditional three for other vaccines. Currently, no vaccine for the disease is available for humans, despite its recent spread in the U.S. and Canada.

The nasal administration, presented at the American Society for Microbiology Biodefense and Emerging Diseases Research Meeting in Washington, D.C., could offer a quick-hit solution to what has become a global issue. The mosquito-borne virus, which can cause inflammation of the brain among other symptoms, has been around in the Middle East, Africa, Europe and Australia for decades, according to a release from the society, but has only in the last 15 years been reported in North America, affecting thousands and killing over 100 in 2013, the CDC says.

For the vaccine, the Duke researchers modified an existing experimental nasal formulation of antigens to cut the number of immunizations needed from three in three weeks to two over a period of two weeks.

In an animal study in which the scientists gave nose drops to mice, the two-dose vaccine protected all of the animals from death by the disease and significantly protected against weight loss associated with West Nile. A smaller dose had a similar effect but was not significant.

"Our results demonstrate that a needle-free (West Nile virus) vaccine using only two vaccine doses is able to induce protective anti-(West Nile) immunity," researcher Herman Staats said in a statement. "A nasally-administered, needle-free vaccine able to rapidly induce protective immunity with minimal vaccine doses per subject would be beneficial for use during (West Nile virus) outbreaks."

- here's the release
- and here's FierceBiotech Research's take