A salmonella scare has prompted a recall of some egg brands across four states and the destruction of hundreds of thousands of hens.
Five people aged in their 20s to 80s contacted salmonella enteritidis linked to eggs produced by Victoria's Bridgewater Poultry, the state's health department confirmed on Thursday.
Two people were taken to hospital for treatment and have since been released.
Symptoms include fever, headache, diarrhoea, abdominal pain, nausea and vomiting and usually start six to 72 hours after consuming the contaminated food and can last up to a week.
Chief Health Officer Brett Sutton said the strain could infect the egg before the shell had formed, and caused "significant food poisoning".
"It is not a normal organism found in eggs in Victoria, indeed Australia," he told reporters.
"It is like an exotic pest, it's the cane toad of salmonella."
The company's free-range and barn-laid eggs are packaged as Woolworths brand, Victorian Fresh, and Loddon Valley, with best-before dates ranging from March 20 to April 29.
They are on shelves in Victoria, NSW, Tasmania and South Australia.
All other eggs are safe to eat, Dr Sutton said.
The health and human services department with Agriculture Victoria inspectors identified the strain at the property during a routine check at the farm on Monday. Quarantine measures have been imposed.
The Victorians cases are suspected to be linked to properties in NSW contaminated last year, with a national investigation underway to determine how they may be connected, Dr Sutton added.
"We need to look into how the complex web of egg distribution in Australia might be linking the properties in NSW and this Victorian property," he said, noting it could take months."
This recall may lead to the culling of hens and their eggs, he flagged.
"There will be hundreds of thousands of eggs involved, hundreds of thousands of laying hens involved, so it is a very big recall," Dr Sutton said.
"It is often the case that culling, de-flocking occurs as a control measure because it is so serious."
The egg cases will be pulled from store shelves, while customers are urged to bin the products or return them to the point of sale for a refund, and not feed them to animals.
Vulnerable people, including the elderly, are urged to avoid eating raw egg products.
Industry group, Australian Eggs, confirmed the nation has some of the world's safest eggs and urged consumers to keep eating except for the at-risk products.
EGGS OF CONCERN
* Woolworths 12 Cage Free Eggs 700g
* Victorian Fresh Barn Laid Eggs 600g
* Victorian Fresh Barn Laid Eggs 700g
* Victorian Fresh Barn Laid Eggs 800g
* Loddon Valley Barn Laid 600g (VIC and SA only)
Best before dates ranging from March 20 to April 29.
