Japanese encephalitis

Japanese encephalitis is an infectious disease that occurs only in Asia and the far northeast of Australia. The disease is caused by a virus that is spread by a mosquito. The virus is naturally found in pigs and large water birds. It can spread between animals or from animals to humans through Culex mosquitoes, which are active in the evening and at night. The risk of infection is highest in tropical regions and is closely associated with the rainy season and therefore the amount of mosquito. For individual travellers, the likelihood of contracting the disease is low. There is no evidence of human-to-human transmission of Japanese encephalitis. The virus primarily occurs in rural areas but can occasionally be found on the outskirts of large cities.

Where is Japanese encephalitis found?

Japanese encephalitis is an infectious disease that occurs only in Asia and the far northeast of Australia. The virus is mainly found in rural areas, but can sometimes be found on the outskirts of large cities.

What are the symptoms?

In most cases, the disease has no severe symptoms, but sometimes the following symptoms can occur:

• Rapid onset of high fever
• Headache
• Muscle pain
• Gastrointestinal issues
• Neck stiffness
• Paralysis 
• Loss of consciousness / disorientation
• Seizures

How can you prevent Japanese encephalitis?

Since the risk of infection for travellers is low, good mosquito prevention methods offer enough protection in most risk areas. Depending on your travel plans and personal circumstances, vaccination might also be recommended. Different guidelines apply for children who stay in a risk area for a longer time compared to adults, particularly because children are at greater risk of severe illness.

More information

If you want to learn more about Japanese encephalitis, please check out the RIVM information page here: Japanese encephalitis | RIVM.