An urgent national recall has been issued for pre-packaged lettuce and salad linked to a salmonella outbreak that has hospitalized two people.

The Victorian Department of Health and Human Services said it had identified a number of cases of the infection linked to lettuce grown and packaged by Victorian company Tripod Farmers.

It is sold at Coles, Woolworths, Bi-Lo and other grocers as Coles 4 Leaf Mix, Woolworths salad mix, SupaSalad Supamix and Wash N Toss salad mix.

The affected products have best before dates leading up to and including February 14 and are in all states and territories except for Tasmania and Western Australia.

The health department identified the lettuce after recording an unusually high level of Salmonella Anatum strain infections and traced a number of those back to the products.

“Normally we only see a handful of cases of this strain each year, but so far this year there have been 28 adult cases of salmonella anatum – mostly adults – notified to the department,” the department’s senior medical advisor Dr Finn Romanes said.

“As a result of following up the food histories of a number of people we have discovered a common source – the Tripod Farmers lettuce.

“Tests of three products from two batches have also tested positive for Salmonella Anatum bacterium.”

“We do expect to see more cases,” he said.

“We are working with the company to understand what may have occurred… They have instituted a comprehensive clean-up to make sure any risk is minimized.”