Murray Valley Encephalitis (MVE)

Murray Valley Encephalitis (MVE)

Murray Valley encephalitis (MVE) is a rare disease in humans in the Murray River valley region of Australia, according to a factsheet from the New South Wales government. It is spread by mosquitoes, and while usually causing only mild symptoms in humans, a small proportion of those infected develop a severe brain infection. The infection is also found in horses, kangaroos and birds, including chickens.

Symptoms

Most MVE infections in people cause no symptoms.

Some people with MVE infections experience an illness with fever, headache, nausea, vomiting and loss of appetite, diarrhoea and muscle aches.

Rarely, the MVE virus can cause a severe brain infection known as encephalitis. The danger signs of MVE encephalitis include the following symptoms:

• severe headache
• neck stiffness
• sensitivity to bright lights (photophobia)
• drowsiness and confusion.

This can progress to cause trouble with coordination and speech, seizures, loss of consciousness, coma and even death. Some people who recover from MVE encephalitis are left with permanent neurological complications.

Spread

• The MVE virus is spread by the common banded mosquito, Culux annulirostris. This mosquito breeds in fresh water and tends to be found in spring, summer and autumn around rivers, natural wetlands and irrigation waters and along coastal areas of NSW. The mosquito is especially common around the Murray Darling River basin areas in NSW during summer