Recently, communities across NSW and VIC have been encouraged to take measures to protect themselves against mosquito bites following the detection of the Murray Valley encephalitis (MVE) virus in both states.
We need to preface this with some key points;
- Murray Valley encephalitis (MVE) is a rare but potentially serious infection of the brain caused by a virus.
- MVE can spread to humans through mosquito bites.
- There is no effective treatment or vaccine for MVE – which is why prevention is key.
Many people with Murray Valley encephalitis have no symptoms. Others may have mild symptoms including fever, headache, nausea, and vomiting. A small number of infected people develop encephalitis, which is an inflammation (swelling) of the brain. This can potentially lead to brain damage or death – again, this is very rare.
Severe symptoms may include:
- fever
- drowsiness
- confusion
- nausea and vomiting
- shaking
- neck stiffness
- headache
- seizures (especially in young children)
- sensitivity to bright light (photophobia)
- loss of consciousness or coma.
Important note: Babies who are infected may also become irritable or drowsy.
If symptoms occur, they usually develop 7 to 12 days after being bitten by an infected mosquito, but this can be as little as 5 days or as long as 28 days.
Anyone with symptoms should seek urgent medical attention.
Preventing mosquito bites
To lessen your chance of being bitten by mosquitoes;
👉🏼 Cover up as much skin as possible and stay inside in the early morning or at dusk.
👉🏼 Mosquitoes are attracted to dark colours, so light-coloured clothes covering to the wrists and ankles should be worn to reduce the possibility of being bitten.
👉🏼 Still water attracts mosquitoes, so keep away from dams, ponds and other sources of still water.
Around the home;
👉🏼 Cover any containers that store water (including swimming pools) so that mosquitoes can’t lay eggs. Empty or drain containers when they are not being used.
👉🏼 Change water in bird baths and watering troughs at least once a week.
👉🏼 Seal and cover cesspools and septic tanks so that mosquitoes can’t lay eggs.
👉🏼 Fill large holes in trees with sand or mortar.
👉🏼 Remove excess vegetation from garden ponds and stock with fish.
👉🏼 Do not over-water the garden.
👉🏼 Use an insect repellent when you are out and about and there are mosquitoes around.
Make sure that you know the safest way to protect them from insects, depending on their age!
👉🏼 Insect repellents should not be used on babies under 3 months old (opt for netting over the pram in problem areas).
👉🏼 For young children, insect repellents are safest if rubbed or sprayed on clothing.
👉🏼 For older children, follow the instructions on the bottle but discontinue use if any skin irritation occurs.
When choosing a repellent;
👉🏼 Know whether the key ingredient in your repellant is DEET or picaridin. More on this at the RCH repellent fact sheet below 👇
👉🏼 Roll-on preparations are preferable to sprays.
👉🏼 Do not use on cuts, wounds or irritated skin.
👉🏼 Do not apply to areas around the eyes or mouth.
👉🏼 Do not apply to the hands or fingers of young children.
👉🏼 When returning indoors, wash repellent off skin with soap and water.
👉🏼 Store repellents out of the reach of children.
Did you know? If you need to apply both sunscreen and repellent, apply the sunscreen first. Products combining sunscreen and insect repellent are not recommended, as sunscreen generally needs to be reapplied more often than insect repellent.
What about Japanese Encephalitis Virus (JEV)?
You may remember our post about JEV last year. There have also been fresh warnings on the transmission of JEV, as we reach the peak of mosquito season.
For more information on Mosquito-borne diseases, visit Healthdirect Mosquito-borne diseases fact sheet.
References + further reading
Murray Valley Encephalitis and mosquito bite prevention- Health Direct
Murray Valley Encephalitis – Better Health VIC
MVE Detected in NSW – NSW Health
Japanese encephalitis virus detected – NSW Health
Japanese encephalitis virus (JEV) – Department of Health
Insect Repellent Fact Sheet/Guide – Royal Children’s Hospital
