It is not yet clear how the staff member, a man, contracted hepatitis A.

However Victoria has been recently experiencing a local outbreak of the infectious disease – which has already claimed one life.

In response to the dozens of cases in recent months, a free vaccine has been offered to Victorian men who have sex with men and people who have injected drugs in the past year.

It follows an unusual increase in hepatitis A cases in Europe and North America that has affected hundreds of people.

A health department spokesman confirmed the infected staff member at Cumulus Inc. was involved in the plating up and preparation of food.

“Someone in that category that is working and unwell can potentially pass it on,” he said.

Senior public health physician Dr Finn Romanes said it was possible more cases of the infection could emerge because of the food handler, as symptoms were often not apparent until 15 to 50 days after infection.

“Information about hepatitis A has been provided to other workers at the restaurant and they are being offered vaccinations. None has reported any illness,” Dr Romanes said.

“The symptoms of hepatitis A are fever, nausea, vomiting and abdominal discomfort, dark urine, yellow skin and eyes [jaundice].

“Hepatitis A is a viral infection of the liver that occurs when the virus is taken ingested. The virus then infects the liver and is passed in the faeces.”

Cumulus Inc. is prolific restaurateur Andrew McConnell’s stalwart all-day city restaurant, with wine bar Cumulus Up operating above.

Occupying an old clothing factory in Flinders Lane, the restaurant has consistently maintained a hat in the Good Food Guide since it opened in 2008.

Famous for its slow-cooked lamb shoulder, and still the go-to for boozy business brunches it is a kingpin of the McConnell restaurant empire, which also includes Marion, Cutler and Co. and fellow Flinders Lane occupant Supernormal.

The department said it was extremely important food handlers practised good personal hygiene at all times, including washing hands thoroughly with soap and running water after visiting the toilet, before eating and before handling food.

For further information visit the Better Health website.

Cumulus Inc. has been contacted for comment.