Japanese encephalitis virus in Australasia: molecular studies of isolates and consequences of immunisation. [ 2001 - 2003 ]

Research Grant

Researchers: Prof John Mackenzie (Principal investigator) ,  Prof Peter Mcminn ,  Prof Roy Hall

Brief description Japanese encephalitis (JE) virus is a mosquito-transmitted virus of Asia. Infection causes clinical disease in about 1 in 50 people infected, and of these, about 25% will die from a fatal encephalitis (inflammation of the brain), and a further 50% will have lifelong severe disabilities. There are over 50,000 cases annually in Asia, with about 12,000 fatalities.The virus normally circulates between mosquitoes and water birds and between mosquitoes and pigs. The World Health Organization has recognised JE as one of the most important mosquito-borne viruses because of its propensity to spread and to colonise new areas. The virus first appeared in northern Australia in the Torres Strait in 1995, causing three clinical cases of whom 2 died, and returned again in 1998, with a further case in the Torres Strait and the first case to occur on mainland Australia in Cape York. Both of these patients recovered. The virus returned again to the Torres Strait in 2000, but so far without causing human disease. We have shown that the virus is established in Papua New Guinea (PNG), where it is spreading rapidly, and our results suggest that PNG was the source of the virus causing the outbreaks in 1995 and 1998. It is believed that JE virus will almost certainly become established in Australia within the next few years. The aims of this project are to explore the consequences of JE becoming established and specifically: (a) the use of inactivated JE vaccine to protect at-risk populations and whether the vaccine will provide sufficient protection or whether it will lead to enhanced infection with indigenous flaviviruses such as Murray Valley encephalitis virus; and (b) the possibility of emergence of genetic variants with increased transmissibility, virulence, and altered neutralisation epitopes.

Funding Amount $AUD 212,036.72

Funding Scheme NHMRC Project Grants

Notes Standard Project Grant