Murray Valley encephalitis in Western Australia - Update 1

The Western Australian Department of Health reports a traveller has been admitted to hospital with Murray Valley encephalitis. In 2023, 2 people have from Murray Valley encephalitis in Western Australia. Four other people have also been infected in the Kimberley region in the last 12 months. The Department of Health strongly advises residents and travellers in the Kimberley region to avoid mosquito bites.

Murray Valley encephalitis virus is transmitted by Culex mosquitoes and can cause fever, headache, nausea, rash, muscle and joint pains, rash and fatigue. More seriously, encephalitis occurs in some cases.

Advice for Travellers

MVE is rare but all travellers to outbreak areas are potentially at risk of infection. The risk is greatest for those:

• participating in outdoor activities during twilight hours
• travelling for a prolonged period of time
• frequently exposed to mosquito bites in rural infected areas (e.g. swamps, wetlands, parks)

All travellers should be advised on:

• the risks and potentially severe consequences of MVE
• practicing strict mosquito bite avoidance measures, including correct use of insect repellents
• minimising outdoor activities during twilight hours when Culex mosquitoes bite

Travellers at increased risk of developing severe clinical disease are those:

• with pre-existing chronic medical conditions
• younger than 10 years of age
• older than 50 years of age

No vaccine is available and there is no specific treatment.

For further information on how to reduce mosquito bites, see the Mosquito Bite Avoidance page.