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Murray Valley encephalitis fact sheet
Page contents: What is MVE? | How is MCE spread? | Where does MCE usually occur? | What are the symptoms? | What is the treatment? | How can MVE be prevented? | Personal protection | Further information | Download document
What is MVE?
Encephalitis is inflammation (swelling) of the brain tissue and is usually caused by an infectious agent such as a virus. MVE is a form of encephalitis that people can catch after being bitten by a mosquito carrying the MVE virus. It can be fatal.
How is MVE spread?
The MVE virus is spread by the bite of an infected mosquito (usually Culex annulirostris also known as the ‘common banded’ mosquito). Not all of these mosquitoes carry the virus, and only about 1 person in 1000 who gets bitten by infected mosquitoes will get sick.
Many people who have the virus show no symptoms. MVE is not spread from person to person.
Where does MVE usually occur?
Although MVE can occur throughout most parts of Australia, it is most common in northern Australia. Recently MVE virus has been found in chickens in the Murray Valley region. These chickens are used as an early warning system for possible human cases of MVE in the area.
There have been no human cases reported to date.
What are the symptoms?
It can take 7 to 28 days between getting bitten and becoming sick.
Symptoms include high fever, severe headache, seizure or fits (especially in young children), neck stiffness, drowsiness, and confusion. In severe cases delirium and coma can follow.
What is the treatment?
There is no specific treatment or vaccine available for MVE but some of the symptoms can be treated.
How can MVE be prevented?
The only protection from MVE is to avoid mosquito bites. All people living in and travelling to areas where mosquitoes are common need to protect themselves against being bitten.
Everyone should protect themselves against mosquito bites, particularly those visiting and camping in or near swamps or rivers during the evening and night, and in rural areas where mosquitoes are common.
Protecting young children and babies against mosquito bites is absolutely essential.
Personal protection includes:
- Avoid being outside when mosquitoes are most active, usually before dawn and from just before and until two hours after sunset.
- Wear loose light coloured clothing with long sleeves, long trousers and socks (mosquitoes can bite through tight-fitting clothes).
- Put mosquito repellent containing DEET (diethyl toluamide) or picaridin onto exposed areas of skin. Lotions and gels work better and last longer than sprays.
- In young children, insect repellents are safest if rubbed or sprayed on clothing rather than skin. Don't spray on the skin of children under the age of one. Choose repellents that contain no more than 10 percent DEET, Repellents should not be used on infants less than 2 months old. Consult with your doctor or pharmacist for further advice and always follow the product instructions.
- Make sure flyscreens in houses or caravans don’t have holes in them.
- When camping, sleep in a mosquito-proof tent or under a mosquito net. Repellents only protect against mosquito bites for up to four hours, not all night.
Further information
You can get more information from the Department of Health, Communicable Disease Prevention and Control Unit on 1300 651 160.
