At least 21 people were struck down with salmonella caused by a bad batch of eggs at a restaurant.

The outbreak, which left some diners hospitalized, has caused 'genuine distraught' to Food Republic's co-owner Vanessa Lekkas who said the Blackburn restaurant would no longer serve food made with raw egg products.

'In almost 30 years of working in the industry we've never seen this happen,' Ms Lekkas told Daily Mail Australia

'We sell thousands of eggs a year, it looks like one of those contained a bad batch of eggs.'

At least 21 people were struck down with salmonella caused by a bad batch of eggs at Blackburn restaurant Food Republic (pictured)

The Department of Health and Human Services was alerted to the outbreak after a number of people were treated for salmonella at Box Hill Hospital

'For this to happen, we're just shocked and devastated,' Ms Lekkas said.

'We want to assure customers that there's no threat to diners - out kitchen is all above board and clean and safe.

She said it's likely the source is from a raw egg egg base, however authorities couldn’t find any trace of salmonella in the kitchen.

The Department of Health and Human Services was alerted to the outbreak after a number of people were treated for salmonella at Box Hill Hospital.

'We can confirm there has been salmonella identified from diners who went the Food Republic restaurant in Blackburn Rd on March 18,' spokesman Bram Alexander told Daily Mail Australia.

The outbreak, which left some diners hospitalised, has left Food Republic's co-owner Vanessa Lekkas 'devastated'

Authorities are now looking into the cause of the salmonella outbreak, which has now been contained

However Mr Alexander could not confirm the source of the infection and was reluctant to speculate.

'Investigations so far haven’t found the source of the salmonella,' he said.

'The tests performed of the samples hasn’t found a positive result, there are a number of foods we’re testing.

'There's no ongoing risk to the public – the restaurant is operating as normal as people should continue to patronise it.'

Ms Lekkas said the restaurant would no longer serve raw egg based products like homemade mayonnaise to reassure customers.

Co-owner Ms Lekkas said they had been fully transparent with the Department of Health and Human Services and Whitehorse Council, who saw that Food Republic's food handling processes met industry standards.

The groups are now looking into the cause of the salmonella outbreak, which has now been contained.