Uncertainties in Tracking West Nile Virus Undermine Vaccine Development

Soon after West Nile virus (WNV) appeared in the United States (US) in 1999, several vaccine efforts were launched, leading to a vaccine deemed suitable for horses by 2001, according to Thomas Monath of Harvard Medical School in Boston, Mass. By last year, however, nearly all other WNV vaccine development efforts had stopped, leaving human populations fully vulnerable to this mosquito-transmitted disease, he says. The practical abandonment of vaccine efforts is but one peculiarity during the brief history of vector-borne WNV disease in North America. It was the focus for several discussions last September during a workshop, “Vector-Borne Diseases: Exploring the Environmental, Ecological, and Health Connections,” convened by the Forum on Microbial Threats, which operates under the auspices of the Institute of Medicine (IOM) in Washington, D.C.