Japanese encephalitis

Japanese encephalitis

Nikki Jurcutz


What is the Japanese encephalitis virus?  

Japanese encephalitis virus or JEV is a rare but serious infection of the brain spread to humans by infected mosquitoes. 

How many people have been infected in Australia recently?  

 There are reported cases in New South Wales, South Australia, Victoria and Queensland. Sadly, two adults have passed away from JEV. It has now been declared a disease of National Significance. 

What does encephalitis mean? 

Encephalitis = swelling to the brain.  

 What are the symptoms of JEV?  

Firstly, take a deep breath; it's rare for infected people to become critically ill. Less than 1% of people infected with JEV will experience symptoms. Most people who contract JEV will have no, or only very mild, symptoms and make a full recovery.   

In rare cases, severe symptoms present, which include:  

 • Neck stiffness 

 • Headache and vomiting  

 • Tremors, seizures or paralysis (seizures are common among children)

 • Confusion or unconsciousness  

 • Neurologic symptoms, weakness, and movement disorders might develop over the next few days Those who experience a severe infection are at risk of permanent neurological complications, and this virus can also be fatal.  

 You can read more about signs of a critically ill child here https://bit.ly/3vQApQJ 

How long does it take for symptoms to present?  

 As mentioned, most people are asymptotic, meaning they are unaware they even have the virus. Those who experience symptoms will usually develop between 5-15 days after being bitten by a mosquito.  

 How is it spread? 

 The Culex species mosquitoes spread JEV. They are commonly found in NSW. The Culex mosquito bites an infected animal (pigs and waterbirds commonly infect mosquitoes) and then bites a human.  

 You cannot get JEV from:  

 • another human  

 • by touching n infected animal  

 • by eating an infected animal like pork or poultry  

Who is at risk?  

People working at and/or living close to piggeries where JEV has been detected People who engage in outdoor activities near high mosquito populated areas and waterways. 

Who is at risk of a severe infection caused by JEV?  

 • Children under 5 

 • Older people  

 Have the floods caused the spike in cases?  

The experts are saying yes. Lots of rainfall, flooding and climate changes seemed to have caused an increase in the spread. Unfortunately, these conditions are excellent for this virus to thrive. 

Prevention is key!  

The best way to avoid JEV is to avoid getting bitten by a mosquito! Here are our top tips:  

 • Mosquitos are most active at dawn and dusk and into the evening, avoid peak biting times by staying inside if possible 

 • Reduce skin exposure: mosquitoes are attracted to dark colours, so light-coloured clothes covering the wrists and ankles and clothing should be light, loose-fitting long-sleeved shirts, long pants and covered footwear and socks  • Children can be protected from mosquitoes by using a carrier and draping a mosquito net over and securing the sides completely 

 • Cover strollers and baby carriers with mosquito netting 

 • Use insect repellent (discussed below)  

 • Stay and sleep in rooms protected with flyscreens and check screens do not have any rips or holes 

 • Don't have any water-holding containers around the home. Mosquitoes only need a small amount of liquid to breed (think buckets, pet bowls, birdbaths) 

 • A vaccine for JEV is available for those aged 2+ months; speak with your GP as up until now, it has mainly been used by Australians travelling overseas. 

 • Use mosquito coils and other devices that release insecticides to assist in reducing mosquito bites; these should be used in combination with topical insect repellents (covered below). 

Insect Repellents and little ones

 Here is the low down on insect repellant.  

 Age:  Do not use insect repellent at all on a child under three months (pop in the pram, cover with netting). The Royal Children's hospital says after three months, you can use the repellent, but it's safest to rub or spray on their clothing. Avoid using directly on their skin until at least 12 months. I am yet to find a chemical-based repellent that allows use under 12 months. 

Most effective? The most effective repellents contain the chemicals DEET or Picaridin. These are considered 'safe'; skin irritation is the most common side effect. Choose a repellent that: 

•Contains no more than 10% DEET or Picaridin 

• Look for repellents especially formulated for children 

What about natural alternatives? 

Chemical active ingredients are more effective, whereas natural alternatives with ingredients like Citronella, Eucalyptus or Tea Tree Oil provide some protection but are less effective. The Royal Children's Hospital recommends using a repellent that contains either DEET or Picaridin for the best protection. 


• Do a test patch before using  

• Use roll-ons over sprays, as inhaling it can be harmful to little lungs  

• Read the label and use it sparingly, avoiding cuts, mouth, eyes etc.  

• Do not put it on your little one's hands - because you know the first place they will go! 

• You should always wash it off their skin once you're back inside 

• Insect repellent is not water-resistant; you must re-apply after swimming 

Sunscreen + repellent 

You should avoid products that combine sunscreen and repellent because you need to re-apply sunscreen much more frequently than repellent, and it will unnecessarily overexpose your bub's beautiful, sensitive skin. If using sunscreen and repellant, apply sunscreen first, wait 20 minutes and then apply the insect repellant. 

 Treatment of JEV 

 There is no specific treatment available for JEV. Those who experience more severe symptoms require supportive care and hospitalisation. Treatment is symptomatic. Rest, fluids, and medication to reduce fever may relieve some symptoms, is all that can be done.

Outcome for people with JEV 

Among patients who develop encephalitis, 20% – 30% die. Although some symptoms improve after the acute illness, 30%-50% of survivors continue to have neurologic, cognitive, or psychiatric symptoms. 

 Stay vigilant and protect your little one! 

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While Tiny Hearts tries to ensure that the content of this blog is accurate, adequate or complete, it does not represent or warrant its accuracy, adequacy or completeness. Tiny Hearts  is not responsible for any loss suffered as a result of or in relation to the use of its blog content... read more

While Tiny Hearts tries to ensure that the content of this blog is accurate, adequate or complete, it does not represent or warrant its accuracy, adequacy or completeness. Tiny Hearts  is not responsible for any loss suffered as a result of or in relation to the use of its blog content.

To the extent permitted by law, Tiny Hearts excludes any liability, including any liability for negligence, for any loss, including indirect or consequential damages arising from or in relation to the use of this blog content.

This blog  may include material from third party authors or suppliers. Tiny Hearts is not responsible for examining or evaluating the content or accuracy of the third-party material and it does not warrant and, to the fullest extent permitted by law, will not have any liability or responsibility for any third-party material. This blog was written for informational purposes only and is not a substitute for professional medical advice. Nothing contained in this blog should be construed as medical advice or diagnosis.The content on our blog should not be interpreted as a substitute for physician consultation, evaluation, or treatment. Do not disregard the advice of a medical professional or delay seeking attention based on the content of this blog.  If you believe someone needs medical assistance, do not delay seeking it. In case of emergency, contact your doctor, visit the nearest emergency department, or call Triple Zero (000) immediately.

The author of this information has made a considerable effort to ensure the information is in-line with current guidelines, codes and accepted clinical evidence at time of writing, is up-to-date at time of publication and relevant to Australian readers. read less

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