UQ researchers develop new vaccine

Two University of Queensland researchers have developed a vaccine that could protect against the deadly West Nile disease.

Dr Roy Hall, from UQ’s School of Molecular and Microbial Sciences, and Dr Alex Khromykh, from the Sir Albert Sakzewski Virus Research Centre based at Brisbane’s Royal Children`s Hospital, created the vaccine from work they were doing on the harmless Kunjin virus.

West Nile and Kunjin have very similar genetic sequences, but Kunjin produces only rare, non-fatal cases of disease and as such provides a very stable vaccine.

West Nile, a mosquito-borne virus that causes flu-like symptoms and
encephalitis, and while the disease is yet to take a foothold in Australia, it has caused numerous human and equine fatalities since entering the United States in 1999.

Because no known cure exists, preventing the disease is a goal of current research, which has been published in the prestigious Proceedings of the National Academy of Sciences journal (PNAS, article 4270).

To determine if exposure to Kunjin provides immunity to West Nile, Dr Hall, Dr Khromykh and colleagues injected mice with varying amounts of a vaccine in the form of DNA that produces replicating, but attenuated Kunjin virus.

After 19 days, the scientists found that blood serum of mice given as little as 0.1 micrograms of the Kunjin DNA vaccine produced antibodies against both Kunjin and West Nile.

When challenged with lethal doses of West Nile virus, immunised mice were protected from disease.

The scientists suggest that vaccination with DNA producing attenuated Kunjin virus could be a safe and effective strategy to prevent West Nile disease.

The vaccine is expected to be further developed for human and veterinary use to help control the disease particularly in North America.

MEDIA: For more information contact Dr Roy Hall (telephone 07 3365 4647), Dr Alex Khromykh (telephone 07 3636 1568) or Andrew Dunne, UQ Communications (telephone 07 3365 2802).