Researchers are developing a DNA-based vaccine against the dreaded West Nile virus (WNV), which can be transmitted from animals to humans. The unique feature of this vaccine is that it is also effective after onset of the disease, for it has therapeutic properties.
SARS, avian flu, Ebola - outbreaks of deadly viral infections are becoming increasingly frequent. And we still don't have vaccines for many of the pathogens responsible. One of the most dangerous classes of viral diseases is the zoonosis, which can be transmitted from animals to humans with sometimes fatal consequences. One of these is caused by the West Nile virus (WNV), which was first identified in Uganda in 1937. The virus was carried to the United States in 1999 and had spread through the whole of North America within five years. There is now a risk that it will propagate worldwide. Since its first appearance in the United States, around 400 people have died there after coming into contact with the West Nile virus. A new vaccine promises to provide protection.