Australian researchers are close to developing a vaccine for the potentially debilitating West Nile virus that causes Japanese encephalitis and dengue.

Alex Khromykh from University of Queensland and colleagues have found a way to generate immune response levels comparable to a live virus vaccine to help such victims. West Nile virus caused outbreaks of viral encephalitis in Europe and the US.

"What this means is that our prototype vaccine has the potential to not only be safer but just as effective as live vaccines," Khromykh said.

West Nile virus has been major global killer since its emergence in 1999, said Khromykh.

"A vaccine is desperately needed and while a number of vaccine candidates are currently in development, none have yet been approved for human use. Following this research we hope to move on to pre-clinical and clinical trials of the vaccine."

He said the vaccine they were developing -- called pKUNdC/C -- is safer, purer and more stable than other vaccines prepared using traditional approaches, such as attenuated live virus vaccines.

"Live virus vaccines are usually more potent though and provoke a greater response from the immune system," he said.

"These findings are important not only for the vaccine development against West Nile virus, but also against other highly pathogenic viruses from the same virus genus which includes dengue, tick-borne encephalitis and Japanese encephalitis viruses."

Details about the research leading up to the vaccine have been published in the latest issue of the journal Nature Biotechnology.