Multiple cases of Japanese encephalitis have now been detected in Australia. Health authorities have responded by classifying the disease as “nationally significant” — but what exactly is Japanese encephalitis and should we be worried about it? Let’s investigate.

According to healthdirect.gov.au encephalitis is “an inflammation of the brain”. It is “rare but it is potentially life-threatening and can lead to permanent brain damage”.

If infected, a person may experience the following symptoms: A high fever, headache, stiff neck, vomiting, light sensitivity, convulsions, drowsiness and confusion.

In severe cases, a person may (and we want to stress “may”) slip into a coma and could even die.

In some cases, people with encephalitis may need to be admitted to hospital

This occurred last Thursday when woman from the NSW/Vic border region was taken to the intensive care ward. Thankfully she has remained in a stable condition as per Guardian Australia.

A second person has since been admitted to intensive care. This was confirmed by Agriculture Minister David Littleproud during an ABC radio broadcast on Monday morning.

Paul Griffin is an infectious disease physician and stressed the rarity of severe Japanese encephalitis cases to the ABC.

“The main thing everyone needs to know is that not everyone who gets this virus ends up with severe encephalitis or the severe manifestations — in most people that’s not the case,” Dr Griffin said.

“It is something that we should take seriously enough to take some simple steps to reduce our chance of it being a big problem.”

Japanese encephalitis in Australia is thought to have originated on pig farms in Queensland, NSW and Victoria as per the Sydney Morning Herald.

A combined press release from Agriculture Minister Littleproud and Health Minister Greg Hunt has since confirmed the presence of Japanese encephalitis in South Australia.

Dr Sonya Bennett, Australia’s Acting Chief Medical Officer, said that “a national approach is required in relation to coordination of health policy, interventions and public messaging”.

“The Department of Health is aware of other cases, in multiple states, of encephalitis of unknown origin that are being investigated for arboviral (AKA: insect) diseases, including Japanese encephalitis.”

So should we be worried?

Until we know how widely the virus has spread, it’ll be hard to gauge just how dangerous it’ll be in Australia.

The World Health Organisation has stated the following:

“Although symptomatic Japanese encephalitis (JE) is rare, the case-fatality rate among those with encephalitis can be as high as 30%.

“There is no cure for the disease. Treatment is focused on relieving severe clinical signs and supporting the patient to overcome the infection.”

“Safe and effective vaccines are available to prevent JE. WHO recommends that JE vaccination be integrated into national immunization schedules in all areas where JE disease is recognized as a public health issue.”

One reason to be a little on your guard is due to the recent flooding across the east coast of Australia since floodwaters can often attract mosquitos.

A fact sheet published by NSW recommends the following:

  • covering-up with a loose-fitting long sleeved shirt and long pants when outside.
  • applying mosquito repellent to exposed skin.
  • removing potential mosquito breeding sites from around the home and screen windows and doors.

Acting Chief Medical Officer Dr Bennett has confirmed that there will likely be a targeted vaccine rollout with an expert working group currently being set up as per the ABC.

Dr Bennett concluded that “The Australian government’s health and agriculture departments are working very closely with their state government counterparts to ensure a swift and coordinated response,” as per Guardian Australia.

Dr Griffin hypothesised that an encephalitis vaccine rollout would not be as far-reaching as that of the COVID vaccine.

“It’s more likely something we’d do on a particular risk basis and so people who work with pigs, in particular, would be highest on the list,” he said.

For more information on the government’s response to the outbreak, the full health alert is available here.

Image: Joao Paulo Burini via Getty