West Nile Vaccine In The Works
Japanese scientists have developed a vaccine for the mosquito-borne West Nile virus and will start testing on humans in the coming months, a researcher said Friday.
The West Nile virus has spread across the United States since first surfacing there in 1999, but Japan has reported no cases so far. Last year, nearly 10,000 people were infected in the United States and 262 died, according to the U.S. Centers for Disease Control and Prevention.
Koichi Morita, virology professor at Nagasaki University's Institute of Tropical Medicine, said his team made the vaccine from an inactive form of the virus sent by American researchers two years ago.
Morita said he would begin small-scale clinical trials on humans to determine whether the vaccine is safe, pending approval from the university's ethics board expected later this year.
Participants will be monitored for side-effects and undergo tests to detect the presence of antibodies — a sign that the body's immune system is responding to fight off the disease.
"The disease could strike in Japan at any time," Morita told The Associated Press. "If the virus ever spreads to Japan, children and the elderly would be the most at risk of infection and death. I want to prevent that from happening."
In the United States, several companies and the government are planning to test potential vaccines over the next three years. Seventy universities and hospitals throughout the United States and Canada will participate in a study this summer in which antibodies from people who had the disease will be injected into people who are infected.
West Nile virus is normally transmitted to humans by mosquitos that have fed on infected birds. Most infected people exhibit no signs of illness, or have mild symptoms such as fever, headache and body aches.
Last month, a Japanese woman who returned to the southernmost island of Okinawa from a trip to the United States tested positive for the West Nile virus. But doctors later ruled out the possibility with more precise tests.