Listeria detected in ham

21 January 2021

Listeria monocytogenes has been detected in ham products distributed by O’Brien’s Wholesale Meats as part of the manufacturer’s routine testing. The affected products include: 

  • O'Brien's Full Boneless Leg Ham
  • O'Brien's Champagne Leg Ham
  • O'Brien's Half Leg Ham
  • O'Brien's Full Leg Ham
  • O'Brien's Half Boneless Leg Ham
  • O'Brien's Third Leg Ham

The ham is also sometimes sold loose from businesses and therefore has no distinct packaging. The affected products have been on sale since December in Foodland, IGA, local butchers, and continental delis across metropolitan Adelaide and rural South Australia. The use by dates of the affected products are: 24/03/21, 01/04/21, and 06/04/21.

To date there have been no cases of listeriosis notified to the Communicable Disease Control Branch (CDCB) linked to this product.

The incubation period for listeriosis is 3-70 days, with an average of 3 weeks. Listeria can survive and multiply rapidly in refrigerated foods. Foods commonly associated with spread of Listeria include: cold meats, pate, raw and smoked seafood, soft, semi-soft, and surface ripened cheeses, soft serve ice cream, and unpasteurised dairy products. Transmission is usually food-borne but spread can also be trans-placental.

Infection with Listeria usually results in no or a mild illness, but can cause serious illness including septicaemia and/or meningitis in vulnerable groups, such as the elderly, immunosuppressed individuals, pregnant women and neonates. Listeriosis can be associated with mild self-limited gastroenteritis in most people, but can cause bacteraemia and/or meningitis, with symptoms including fever, headache, backache, nausea, vomiting, neck stiffness, gradual confusion or decreased alertness. Pregnant women may have relatively mild symptoms (fever and aches) and make a quick recovery. However, they may transfer the infection to their unborn child who may be stillborn or born very ill.

Doctors are asked to:

  • Consider listeriosis in any unwell patients presenting with the symptoms mentioned above, especially those in the vulnerable groups, with a history of consumption of implicated products.
  • Consider if transfer of any suspected case to hospital is required.
  • Discuss any suspected case with an infectious disease physician.
  • Take sterile site samples from any suspected case appropriate to the presentation e.g. blood cultures, cerebrospinal fluid. A stool sample cannot be used for diagnosis of Listeria.   
  • Notify suspected and confirmed cases of listeriosis to CDCB on 1300 232 272.
  • Provide patients as appropriate with listeriosois fact sheet, available from:

If you require further information, please call 1300 232 272 (24 hours/ 7 days)

Dr Louise Flood – Director, Communicable Disease Control Branch

View the official health alert here

Share this article