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Japanese encephalitis virus

Japanese encephalitis virus (JEV) is spread by mosquito bites. Most people infected have no symptoms or mild fevers and headaches. In about one in 100 people it can cause severe disease and sometimes death. It doesn’t spread from human to human.

What is Japanese encephalitis virus?

JEV is a viral infection that affects the central nervous system and can cause inflammation of the brain, which can be fatal.

Mosquitos get infected by biting an infectious animal (such as pigs or water birds) and then they carry it to the next creature they bite. Although humans and horses can be infected, they can’t transmit the virus to others. JEV cannot be spread from human to human. It doesn’t spread from pigs to humans and there is no risk of catching the virus from eating pork.

There is a vaccine available and if you or your staff work in industries or areas where there is risk, we recommend you get the vaccination.

You or your staff might be at risk if you:

  • work at, live near or have a planned visit to:
    • a piggery, including farm workers and their families living at the piggery, transport workers, veterinarians and others involved in the care of pigs
    • a pork abattoir or pork rendering plant.
  • are pig doggers and hunters
  • work directly with mosquitoes through their surveillance (field or laboratory based) or control and management such as:
    • environmental health officers and workers (urban and remote)
    • entomologists.
  • work in a diagnostic and research laboratory and may be exposed to the virus
  • live or work in the local government areas of Balonne, Goondiwindi, North Burnett, Western Downs or Southwest Toowoomba Regional Council (surrounding and including Millmerran)
  • spend time outdoors near mosquito habitats (rivers, ponds and marshes, including flood zones and wherever there is stagnant water)
  • live or work in the Torres Strait and/or Northern Peninsula Area of Cape York.

JEV is a nationally notifiable disease.

Notify us if a worker is exposed to JEV.

What are the risks of JEV?

Although only one per cent of people bitten by JEV carrying mosquitoes become sick, those who do develop the disease can become very unwell, with symptoms like fever and headache.

Severe disease is characterised by an inflammation of the brain, with sudden onset of high fever and chills, severe headache, sensitivity to bright light, neck stiffness, nausea, convulsions, and coma.

Of these severe cases, approximately one third die and one third are left with permanent disabilities. (QH website).

How do I manage the risks?

Prevent mosquito bites as much as possible.

Workers and management can work together to reduce the risks of hazards at work.

For workers

As a worker, you have a responsibility to take reasonable care of your own health and safety and make sure that your work doesn’t have a negative impact on the health and safety of others.

Use equipment properly, follow safe work policies and procedures, and attend training. If something is unclear or you are uncertain, ask for an explanation.

For businesses

For employers or persons conducting a business or undertaking (PCBU), it’s your duty to manage Japanese encephalitis virus risks, as outlined in the Work Health and Safety Act 2011.

You must provide and maintain a working environment where employees, contractors and visitors are not exposed to hazards:

  • Ensure safe systems of work are in place.
  • Implement safe work practices and provide information, training and supervision.
  • Encourage an environment of consultation and cooperation.
  • Provide personal protective equipment (PPE), and ensure there are systems for PPE inspection, maintenance, cleaning and storage.
  • Provide insect repellent for use.

Following the four-step risk management process below will help your business meet its responsibilities under work health and safety (WHS) laws. You can also use the practical advice in the How to manage work health and safety risks code of practice 2021 (PDF, 0.65 MB).

Four steps to manage risk

Educate yourself on the symptoms of JEV in pigs and horses.

  1. Inspect your business

    Think about your workplace and note where your work environment or processes create the risk of exposure to mosquito-borne diseases.

  2. Talk to your workers

    Talk to your workers to find out if they have any health and safety concerns. A confidential survey could give workers who are less likely to speak out in public a chance to provide feedback.

  3. Review information
  • Monitor where JEV is reported in your region—it is an emerging disease and wet seasons make it worse because there is a lot of rain and that creates good breeding conditions for mosquitos.
  • Use your own records of reported infections, sick leave and other notes.
  • Read the information provided by industry bodies, as well as the relevant legislation and codes of practice.
  • Research how other workplaces have managed mosquito-borne infection risks. Ask your peers and advisors and use the internet to find information specific to your situation.

Find more information on how to identify risks in How to manage work health and safety risks code of practice 2021 (PDF, 0.65 MB) .

Do a risk assessment to establish:

  • if there is a risk to you or others
  • whether any effective control measures are already in place
  • what actions you could take to control the risk
  • how urgently you should act.

A risk assessment can include looking at:

  • the nature of your work and how this exposes workers and others
  • what inductions and training you have in place
  • whether the work is required or if it can be rescheduled, reorganised, or restructured to reduce the risk
  • seasonal considerations (eg wet season).

Use this risk assessment template (DOCX, 0.02 MB) to guide and record your assessments.

After assessing the risk, use control measures to eliminate or reduce the risk. Eliminate JEV risks as much as reasonably possible. If this is not possible, minimise the risks.

The hierarchy of control is a step-by-step approach to eliminating or reducing risk. It ranks risk controls from the highest level of protection and reliability through to the lowest and least reliable protection.

Implement control measures in this order

  • Level 1: Get rid of the harm and prevent the risk.
  • Level 2: Replace the hazard with something less harmful, separate people from the hazard, or change work processes or the physical work environment.
  • Level 3: Use administrative controls to reduce exposure (such as limiting time spent in a hazardous area) or use PPE to protect people from harm.

Eliminate the risk of exposure to JEV

  • Vaccinate staff against JEV.

Minimise the risk of exposure to JEV

  • Remove mosquito breeding sites—empty containers, prevent water collecting around living and working areas.
  • Change work processes and redesign tasks to minimise the number of workers exposed to mosquito bites.
  • Update or improve your workspace including onsite accommodation—have mosquito screens on windows and doors.
  • Wear protective clothes—long, light-coloured and loose-fitting clothes and covered shoes.
  • Use mosquito repellent that contains picaridin, DEET or oil of lemon eucalyptus on all exposed skin and reapply every few hours.
  • Install mosquito zappers where possible.
  • Limit your time outdoors at dawn and dusk when mosquitoes are most active.
  • Have a biosecurity plan for your workplace.

Risk management is an ongoing process. Check regularly to make sure the control measures are working. If you find problems or if you have a JEV infection or outbreak, go through the steps again, review the information and decide whether you need new controls.

Under work health and safety laws you must review the controls:

  • when you become aware that a control measure is not working effectively
  • before a change that might create a new risk
  • when you find a new hazard or risk
  • when your workers tell you that a review is needed
  • after a health and safety representative requests a review.

You can find a list to help you find any issues in the How to manage work health and safety risks code of practice 2021 (PDF, 0.65 MB).