Eggs are being urgently recalled across Sydney after an outbreak of salmonella, with 23 cases so far confirmed.

The NSW Food Authority has revealed some Glendenning Farm brand products – from supplier Eggz on the Run – were voluntarily recalled over fears they’d been contaminated with Salmonella enteritidis.

The authority urged anyone who has bought them to return them for a refund and seek medical help if they’re worried for their health.

The recall refers to Glendenning Farm whole shell eggs sold in NSW with best before dates of September 8, 10, 15, 17, 22, 24, 29 or October 1.

They will have been sold in small independent supermarkets and retailers across Sydney in cartons and bulk trays.

“Either bin or return them to the place of purchase for a full refund,” the NSW Food Authority said in a statement. “You do not require proof of purchase for a recalled item.”

Symptoms of salmonella include diarrhoea, fever, vomiting, chills and abdominal pain. They usually develop between six to 72 hours, or more frequently between 12 to 36 hours, after the food is eaten.

Read more: Salmonella outbreak linked to popular fruit

While the illness will generally pass without medical attention within four to seven days, it can exacerbate some conditions and can cause hospitalisation.

According to the Mail Online, the government has now restricted the movement of livestock, eggs, manure and disposables at the farm, as well as ordering the disinfection of equipment.

If you think that you have contracted salmonella, you should see your doctor.

Have you bought these eggs? Do you think you could be at risk?