Global search under way to secure Japanese encephalitis vaccines

The encephalitis (JEV) outbreak keeps worsening with more cases confirmed each day in most mainland states in both humans and piggeries.

NSW has joined Victoria and Queensland with confirmations of cases of JEV infections among people.

A rising number of South Australians also have the mosquito-borne encephalitis but are waiting on clinical confirmations of JEV.

The number of piggeries around the country with confirmed outbreaks has reached more than 40, with authorities saying more are likely to follow.

The federal government has already drawn on a national stockpile of vaccines kept in case of an outbreak like this.

Agriculture Minister David Littleproud said those vaccines had been sent to states already.

At risk farm workers have been identified as first to be offered the vaccine.

"There are more on the way," Mr Littleproud said.

"In fact, we've got another order that we bought in from Korea that will be distributed as well.

"So we're working with the states on the ground and their health units to determine the quantities that they believe they require. But it is a readily available vaccine that we can obtain very quickly, and that's what we're doing."

There are two JEV vaccines available in Australia, one needs two doses 7-28 days apart, and the other requiring a single dose.

The two dose vaccine is recommended for children, pregnant women and those with compromised immune systems.

NSW has confirmed its first two cases of JEV, both from NSW/Victorian border areas.

NSW public health physician Katherine Todd said 10 or more possible cases of the disease are being investigated.

"For a very small proportion of people, less than one per cent, it can cause a severe neurological illness that can have quite bad outcomes, that's why we're taking this so seriously and we're really trying to get the message out to people that this is out there and they really need to take measures to protect themselves," Dr Todd said.

A man from the Corowa area and a child from the Wentworth area are both currently being treated in hospitals in Victoria.

MORE READING: Outbreak a reminder we can't keep everything out.

The virus cannot be transmitted between humans, and it cannot be caught by eating pork or pig products.

Mosquito control activities are being carried out in the vicinity of farms where pigs are confirmed to have been infected by JEV and NSW Health is arranging vaccination of workers on affected farms.

NSW Health said in a statement it was working closely with the NSW Department of Primary Industries and other state and territory agencies "to determine the extent to which the virus is circulating, through animal testing and mosquito monitoring".

Some Queensland councils have already ramped up spraying of mosquito breeding areas in response to recent flooding and the worsening JEV outbreak.

Moreton Bay Mayor Peter Flannery said ground crews had already been sent to spray mosquito breeding areas in fresh water.

"... when waters recede around salt marshes we will launch aerial treatments in those areas,' he said.

Victoria has confirmed JEV outbreaks at six piggeries located in the shires of Loddon, Campaspe, Wangaratta, Gannawarra, Greater Shepparton and Greater Bendigo.

The number of suspected cases in Victoria has grown to eight, which includes two children, with six in hospital.

Agriculture Victoria staff are continuing surveillance activities and providing information and advice to farmers.

Victoria's chief veterinary officer Dr Graeme Cooke is urging anyone who owns pigs or horses to take steps to reduce exposure to mosquitoes.

People cannot be infected by eating pig meat.

Nationally agreed movement restrictions have been applied to infected pig properties to reduce the spread of the disease in pigs.

"Agriculture Victoria is working closely with the Department of Health to understand the implications, and to communicate to farmers how they can reduce the risk to farm workers."

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