Vaccine for West Nile Virus

Researchers have engineered a vaccine that stimulates immunity in mice against the West Nile virus. The virus was first reported in humans in North America in 1999, when the disease surfaced in New York City, killing seven people. The virus can cause potentially fatal inflammation of the brain. Mosquitoes become infected through contact with an infected bird, and can transmit the virus to humans and animals by biting them. The infection is not contagious among humans, however. David B Weiner and colleagues at the University of Pennsylvania, USA, used mice to test the vaccine constructed from DNA specially tailored to produce a protein found in the outer protein shell of the virus.