Listeria monocytogenes in foods in Norway.

Three-hundred-and-eighty-two samples of different retail food items in Norway (imported soft cheese, raw chicken, minced meat, fermented sausages, vacuum-packed processed meat products, smoked salmon, peeled shrimps, raw minced fish) and 78 carcass samples (sheep, pig, cattle), were screened for Listeria monocytogenes. Of the 460 samples investigated, 78 were found to contain L. monocytogenes. Five of these contained greater than 10(3) cfu/g, four greater than 10(2) cfu/g, while the remainder were shown to contain L. monocytogenes only after enrichment. L. monocytogenes was isolated most frequently from raw chicken, sporadically from soft cheese, shrimps, processed meat products and smoked salmon, and not at all from carcasses and fermented sausages.